144 results on '"Smith, Christopher J."'
Search Results
2. Indicators of Global Climate Change 2022: annual update of large-scale indicators of the state of the climate system and human influence.
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Forster, Piers M., Smith, Christopher J., Walsh, Tristram, Lamb, William F., Lamboll, Robin, Hauser, Mathias, Ribes, Aurélien, Rosen, Debbie, Gillett, Nathan, Palmer, Matthew D., Rogelj, Joeri, von Schuckmann, Karina, Seneviratne, Sonia I., Trewin, Blair, Zhang, Xuebin, Allen, Myles, Andrew, Robbie, Birt, Arlene, Borger, Alex, and Boyer, Tim
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GREENHOUSE gases , *RADIATIVE forcing , *CLIMATE change , *OPEN scholarship , *SURFACE temperature ,PARIS Agreement (2016) - Abstract
Intergovernmental Panel on Climate Change (IPCC) assessments are the trusted source of scientific evidence for climate negotiations taking place under the United Nations Framework Convention on Climate Change (UNFCCC), including the first global stocktake under the Paris Agreement that will conclude at COP28 in December 2023. Evidence-based decision-making needs to be informed by up-to-date and timely information on key indicators of the state of the climate system and of the human influence on the global climate system. However, successive IPCC reports are published at intervals of 5–10 years, creating potential for an information gap between report cycles. We follow methods as close as possible to those used in the IPCC Sixth Assessment Report (AR6) Working Group One (WGI) report. We compile monitoring datasets to produce estimates for key climate indicators related to forcing of the climate system: emissions of greenhouse gases and short-lived climate forcers, greenhouse gas concentrations, radiative forcing, surface temperature changes, the Earth's energy imbalance, warming attributed to human activities, the remaining carbon budget, and estimates of global temperature extremes. The purpose of this effort, grounded in an open data, open science approach, is to make annually updated reliable global climate indicators available in the public domain (10.5281/zenodo.8000192, Smith et al., 2023a). As they are traceable to IPCC report methods, they can be trusted by all parties involved in UNFCCC negotiations and help convey wider understanding of the latest knowledge of the climate system and its direction of travel. The indicators show that human-induced warming reached 1.14 [0.9 to 1.4] ∘ C averaged over the 2013–2022 decade and 1.26 [1.0 to 1.6] ∘ C in 2022. Over the 2013–2022 period, human-induced warming has been increasing at an unprecedented rate of over 0.2 ∘ C per decade. This high rate of warming is caused by a combination of greenhouse gas emissions being at an all-time high of 54 ± 5.3 GtCO 2 e over the last decade, as well as reductions in the strength of aerosol cooling. Despite this, there is evidence that increases in greenhouse gas emissions have slowed, and depending on societal choices, a continued series of these annual updates over the critical 2020s decade could track a change of direction for human influence on climate. [ABSTRACT FROM AUTHOR]
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- 2023
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3. Indicators of Global Climate Change 2022: Annual update of largescale indicators of the state of the climate system and the human influence.
- Author
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Forster, Piers M., Smith, Christopher J., Walsh, Tristram, Lamb, William F., Palmer, Matthew D., von Schuckmann, Karina, Trewin, Blair, Allen, Myles, Andrew, Robbie, Birt, Arlene, Borger, Alex, Boyer, Tim, Broersma, Jiddu A., Lijing Cheng, Dentener, Frank, Friedlingstein, Pierre, Gillett, Nathan, Gutiérrez, José M., Gütschow, Johannes, and Hauser, Mathias
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GREENHOUSE gases , *RADIATIVE forcing , *CLIMATE change , *OPEN scholarship , *SURFACE temperature ,PARIS Agreement (2016) - Abstract
Intergovernmental Panel on Climate Change (IPCC) assessments are the trusted source of scientific evidence for climate negotiations taking place under the United Nations Framework Convention on Climate Change (UNFCCC), including 60 the first global stocktake under the Paris Agreement that will conclude at COP28 in December 2023. Evidence-based decision making needs to be informed by up-to-date and timely information on key indicators of the state of the climate system and of the human influence on the global climate system. However, successive IPCC reports are published at intervals of 5-10 years, creating potential for an information gap between report cycles. We base this update on the assessment methods used in the IPCC Sixth Assessment Report (AR6) Working Group One (WGI) report, updating the monitoring datasets and to produce updated estimates for key climate indicators including emissions, greenhouse gas concentrations, radiative forcing, surface temperature changes, the Earth's energy imbalance, warming attributed to human activities, the remaining carbon budget and estimates of global temperature extremes. The purpose of this effort, grounded in an open data, open science approach, is to make annually updated reliable global climate indicators 70 available in the public domain (https://doi.org/10.5281/zenodo.7883758, Smith et al., 2023). As they are traceable and consistent with IPCC report methods, they can be trusted by all parties involved in UNFCCC negotiations and help convey wider understanding of the latest knowledge of the climate system and its direction of travel. The indicators show that human induced warming reached 1.14 [0.9 to 1.4] °C over the 2013-2022 period and 1.26 [1.0 to 1.6] C in 2022. Human induced warming is increasing at an unprecedented rate of over 0.2 °C per decade. This high rate of warming is caused by a combination of greenhouse gas emissions being at an all-time high of 57 ± 5.6 GtCO2e over the last decade, as well as reductions in the strength of aerosol cooling. Despite this, there are signs that emission levels are starting to stabilise, and we can hope that a continued series of these annual updates might track a real-world change of direction for the climate over this critical decade. [ABSTRACT FROM AUTHOR]
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- 2023
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4. 21st Century Scenario Forcing Increases More for CMIP6 Than CMIP5 Models.
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Fredriksen, Hege‐Beate, Smith, Christopher J., Modak, Angshuman, and Rugenstein, Maria
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TWENTY-first century , *RADIATIVE forcing , *ATMOSPHERIC models , *CLIMATE change , *CARBON dioxide - Abstract
Although the Coupled Model Intercomparison Project 6 (CMIP6) protocol provides an experiment to estimate effective radiative forcing (ERF), it is only quantified for few models. We present new estimates of ERF for models participating in CMIP6 by applying the method developed in Fredriksen et al. (2021, https://doi.org/10.1029/2020JD034145), and validate our approach with available fixed‐SST forcing estimates. We estimate ERF for experiments with abrupt changes of CO2, 1% increase of CO2, historical forcings, and future scenarios, and demonstrate that CMIP6 ERF is lower than CMIP5 ERF at the end of the historical period, but grows faster than CMIP5 in the future scenarios, ending up at higher levels than CMIP5 at the end of the 21st century. The simulated radiative efficiency of CO2 has not changed much, suggesting that the larger future increase in CO2 concentrations in CMIP6 compared to CMIP5 is important for explaining the forcing difference. Plain Language Summary: To understand climate model responses, it is useful to separate between the drivers of climate change and their responses. We present new estimates of the drivers, called the effective radiative forcing, for the latest generation of climate models (Coupled Model Intercomparison Project 6 (CMIP6)). This estimates the energy imbalance at the top of the atmosphere and is a measure of human and natural influences on climate. Normally this requires additional climate model experiments to make these estimates, but since these have only been run for a few models, we are here aiming to make the best alternative estimates based on more widely available data, following the method in Fredriksen et al. (2021, https://doi.org/10.1029/2020JD034145). We show that our forcing estimates are growing faster during the 21st century for the new CMIP6 models than for the previous generation of models (CMIP5), and suggest this can be attributed to the higher CO2 concentrations in future scenarios for CMIP6 compared to CMIP5. Key Points: Our method to estimate effective radiative forcing based on common model diagnostics is consistent with Coupled Model Intercomparison Project 6 (CMIP6) fixed‐SST estimatesWe present coherent estimates for abrupt CO2, 1% CO2, historical, and future scenario experimentsForcing estimates for the 21st century grow faster for CMIP6 than for CMIP5 models [ABSTRACT FROM AUTHOR]
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- 2023
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5. The Etruscans: Setting New Agendas.
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Potts, Charlotte R. and Smith, Christopher J.
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ETRUSCANS , *RELIGIOUS behaviors , *DATA analysis - Abstract
The Etruscans, who dominated central Italy for much of the first half of the first millennium BC, are ripe for new analysis: the quantity of data for their culture is now substantial, wide ranging, and qualifies for large-scale comparison. In this paper, we survey how research in the last decade has affected our understanding of settlements, of changing models of the transfer of ideas, and of Etruscan religious behavior, among other topics. We place them into complex spatial, architectural, and economic narratives to show that the interplay between microhistorical case studies and macrohistorical trends has now achieved what ought to be a paradigmatic status. Despite the continuous flow of specialist publications and an industry of exhibitions, however, the Etruscans have not broken through into mainstream archaeological awareness. We argue that this could be achieved if future research becomes more thematic and agenda driven and embraces comparative study. [ABSTRACT FROM AUTHOR]
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- 2022
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6. Linking Species Functional Traits to Specific Biogeochemical Processes under Trawling Pressure.
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Tsikopoulou, Irini, Smith, Christopher J., Papadopoulou, Konstantia Nadia, and Austen, Melanie C.
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TRAWLING , *CHLOROPHYLL in water , *NUTRIENT cycles , *BOTTOM water (Oceanography) , *FISHING nets , *COLLOIDAL carbon - Abstract
Simple Summary: Bottom trawls when fishing move over large areas with different parts of the gears physically impacting the sea bottom, including the trawling wires, doors, ground rope and net. In this way, the trawl nets remove animals from bottom waters, the sediment surface and shallow sub-surface. The animals that live in the sea bottom with their activities and lifestyle play an important role in major ecosystem processes such as nutrient cycling. In this study, we investigated the relationship between species functional characteristics and ecosystem functions under trawling pressure. Our results indicated that under trawling, more opportunistic lifestyles and deposit feeders were associated with the ecosystem processes while in the undisturbed areas these processes were connected with bioturbating and burrowing species. Finding these links helps scientists and policy makers to better predict the impact of fishing disturbance on marine environment and set appropriate thresholds for marine ecosystem impacts. The impact of otter trawling on the relationship between functional traits of benthic invertebrates and specific biogeochemical processes were investigated in the oligotrophic Cretan Sea. The fishery is managed through a seasonal closure during the summer. During two seasons (winter and summer) replicate samples were taken from the field from a commercial trawl ground and an adjacent control area. Environmental parameters related to sediment biogeochemistry were measured including particulate organic carbon, sedimentary organic carbon, bottom water and sedimentary chlorophyll a and phaeopigment concentrations as well as benthic oxygen consumption. A significant impact of trawling was recorded only for bottom water chlorophyll and sedimentary organic carbon. Furthermore, the links between species traits and specific ecosystem processes were affected by trawling, highlighting the importance of unique functional modalities on ecosystem functioning. The traits that mostly influenced benthic biogeochemistry in the control sites were related to bioturbation and burrowing activities. In contrast, in the trawled sites, the associated traits were related to more opportunistic lifestyles and deposit feeding species that do not act as bioturbators. Thus, under trawling disturbance, this shift can decouple the species-sediment relations and affect nutrient cycling. [ABSTRACT FROM AUTHOR]
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- 2022
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7. 13C methodologies for quantifying biochar stability in soil: A critique.
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Chalk, Phillip and Smith, Christopher J.
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BIOCHAR , *SOILS , *ORGANIC compounds - Abstract
Methodologies based on 13C‐enrichment (E), 13C‐depletion (D) and 13C‐natural abundance (NA) to estimate the stability of biochar in soil were critically examined. The stability of 13C‐enriched biochar can be estimated by the quantitative recovery of excess 13C, either in the soil or in evolved CO2. Both approaches have advantages and disadvantages. Recovery in the soil is a measure of both residual biochar 13C + 13C immobilised in soil organic matter during biochar decomposition. Variable proportions of organic‐ and inorganic‐C are present in alkaline biochars, and few data exist on the uniformity of labelling, which is a basic requirement of the respired 13CO2 and E methodology. The E technique has had limited application due to the cost and difficulty of obtaining a uniformly‐enriched feedstock through continuous labelling of plants with 13CO2 at a constant 13C enrichment. In contrast, the NA technique has been widely applied. The NA and D techniques are in situ methods that involve the addition of C4‐derived biochar to a C3‐soil or vice versa. Stability is estimated by a two‐end‐member mixing model that allows the proportion of evolved CO2 derived from the biochar (Cdfb) to be estimated. The mixing model has recently been misused to estimate the Cdfb of 13C‐enriched biochar, with 13C‐abundance expressed as erroneously large δ values. 13C‐based methods provide a yardstick against which rapid stability tests should be evaluated. While numerous laboratory incubation comparisons have been conducted, very few field‐based data have been published. Highlights: 13C methods for estimating biochar stability are based on uniform isotopic labelling.Organic and inorganic constituents of biochar may not be uniformly labelled.Expression of 13C enriched biochar as large δ values (>500 units) rather than atom fraction excess led to larger errors in stability estimation.Few 13C field‐based estimates of biochar stability exist. [ABSTRACT FROM AUTHOR]
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- 2022
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8. Tracing boron dynamics in agro-ecosystems using enriched (10B, 11B) stable isotopic signatures: A centennial legacy.
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Chalk, Phillip, Smith, Christopher J., Chen, Deli, and He, Ji-Zheng
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BORON isotopes , *INDUCTIVELY coupled plasma mass spectrometry , *ISOTOPIC signatures , *PLANT nutrition , *PHYSICAL mobility , *BORON - Abstract
For many years after the discovery of the two stable isotopes of B (10B,11B) in 1920 it was not used routinely as a tracer in the biological sciences until the development of inductively coupled plasma mass spectrometry in the early 1980s. This development provided an impetus to the study of the role of B in plant nutrition, although many seminal discoveries were made beforehand without the aid of isotopes. Thus, much information on the mobility and physiological function of B in plants is post-1985. Boron is unusual in plant nutrition in that it is taken up by plants through roots or foliage as undissociated boric acid, unlike other essential elements that are taken up in ionic form. The within-plant mobility of B in species important in agriculture and horticulture is examined in the present review including the role of sugar alcohols in xylem to phloem transfer. The molecular basis of its movement at the cellular level via transporters as revealed through the strategic application of enriched 11B and 10B is addressed. Few studies have been carried out on B use efficiency by crops and results show great variability. Suggestions for future applications of tracing with 10B and 11B are provided. [ABSTRACT FROM AUTHOR]
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- 2022
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9. Suppressed Late‐20th Century Warming in CMIP6 Models Explained by Forcing and Feedbacks.
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Smith, Christopher J. and Forster, Piers M.
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AIR pollutants , *GREENHOUSE gases , *CLIMATE feedbacks , *CLIMATE sensitivity , *SOLAR activity , *PSYCHOLOGICAL feedback - Abstract
For the 1960–2000 period, the latest generation of climate models (Coupled Model Intercomparison Project Phase 6 [CMIP6]) shows less global mean surface temperature change relative to pre‐industrial than that seen in observations. In contrast, the previous generation of models (CMIP5) performed well over this period. It has been hypothesized that this suppressed late‐20th Century warming seen in CMIP6 is caused by a stronger aerosol forcing. However, we find this to be only part of the story. Not only is the aerosol forcing marginally more negative in CMIP6 compared to CMIP5, the greenhouse gas forcing in CMIP6 is also weaker than in CMIP5. These forcing differences are amplified by differences in climate sensitivity between the CMIP5 and CMIP6 ensemble, which leads to both a stronger aerosol cooling over 1960–1990 and a stronger greenhouse gas induced warming from 1990, returning the warming post‐2000 toward the observed level. Plain Language Summary: Climate models are our best tools for predicting how the climate will change in the future. Confidence in future projections relies on the ability to accurately simulate the past. Many of the latest climate models show less warming than observations around the 1960–2000 period, so understanding why is key to making more confident projections. Models respond to human and natural forcings such as greenhouse gases, air pollutants (aerosols), volcanic eruptions, and solar activity. We show that the latest models simulate a lower forcing from greenhouse gases and aerosols than older models, which is part of the reason why the climate does not warm in line with observations in the late 20th Century. The other part of the reason for the lower warming is that the newer models are more sensitive: they project a greater temperature change for a given amount of forcing. The higher sensitivity is found to result in more cooling from aerosols in the new models, but it opposes the lower forcing from greenhouse gases. The aerosol effects win out, causing suppressed warming in the late 20th Century. Key Points: Coupled Model Intercomparison Project Phase 6 (CMIP6) models warm less in the multimodel mean than CMIP5 models in the 1960–2000 periodImplied forcing from greenhouse gases and aerosols is lower (more negative) in CMIP6 than in CMIP5Stronger climate feedbacks in CMIP6 amplifies the cooling from aerosols [ABSTRACT FROM AUTHOR]
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- 2021
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10. Suppressed Late‐20th Century Warming in CMIP6 Models Explained by Forcing and Feedbacks.
- Author
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Smith, Christopher J. and Forster, Piers M.
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AIR pollutants , *GREENHOUSE gases , *CLIMATE feedbacks , *CLIMATE sensitivity , *SOLAR activity , *PSYCHOLOGICAL feedback - Abstract
For the 1960–2000 period, the latest generation of climate models (Coupled Model Intercomparison Project Phase 6 [CMIP6]) shows less global mean surface temperature change relative to pre‐industrial than that seen in observations. In contrast, the previous generation of models (CMIP5) performed well over this period. It has been hypothesized that this suppressed late‐20th Century warming seen in CMIP6 is caused by a stronger aerosol forcing. However, we find this to be only part of the story. Not only is the aerosol forcing marginally more negative in CMIP6 compared to CMIP5, the greenhouse gas forcing in CMIP6 is also weaker than in CMIP5. These forcing differences are amplified by differences in climate sensitivity between the CMIP5 and CMIP6 ensemble, which leads to both a stronger aerosol cooling over 1960–1990 and a stronger greenhouse gas induced warming from 1990, returning the warming post‐2000 toward the observed level. Plain Language Summary: Climate models are our best tools for predicting how the climate will change in the future. Confidence in future projections relies on the ability to accurately simulate the past. Many of the latest climate models show less warming than observations around the 1960–2000 period, so understanding why is key to making more confident projections. Models respond to human and natural forcings such as greenhouse gases, air pollutants (aerosols), volcanic eruptions, and solar activity. We show that the latest models simulate a lower forcing from greenhouse gases and aerosols than older models, which is part of the reason why the climate does not warm in line with observations in the late 20th Century. The other part of the reason for the lower warming is that the newer models are more sensitive: they project a greater temperature change for a given amount of forcing. The higher sensitivity is found to result in more cooling from aerosols in the new models, but it opposes the lower forcing from greenhouse gases. The aerosol effects win out, causing suppressed warming in the late 20th Century. Key Points: Coupled Model Intercomparison Project Phase 6 (CMIP6) models warm less in the multimodel mean than CMIP5 models in the 1960–2000 periodImplied forcing from greenhouse gases and aerosols is lower (more negative) in CMIP6 than in CMIP5Stronger climate feedbacks in CMIP6 amplifies the cooling from aerosols [ABSTRACT FROM AUTHOR]
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- 2021
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11. Organic N compounds in plant nutrition: have methodologies based on stable isotopes provided unequivocal evidence of direct N uptake?
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Smith, Christopher J. and Chalk, Phillip M.
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STABLE isotopes , *PLANT nutrition , *ORGANIC compounds , *STABLE isotope analysis , *PLANT roots , *PLANT cells & tissues , *NUTRITIONAL genomics , *DUAL-energy X-ray absorptiometry - Abstract
During the past two decades, interest has developed in regard to the possibility that plant roots can take up organic N compounds directly, a concept which challenges the conventional wisdom that soil inorganic N forms ( NH 4 + and NO 3 − ) are the sole primary sources of N absorbed by plant roots. We reviewed the literature based on single or dual (15N, 13C) stable isotope labelling techniques to test the hypothesis of direct uptake. Both isotopically enriched and natural abundance approaches were reviewed. Of the methods examined, the dual enrichment technique, when combined with compound specific and position-specific stable isotope analysis, provided incontrovertible evidence for direct uptake of simple amino acids. We demonstrate that dual labelling lacks overall sensitivity due to the high C concentration in plant tissue relative to N, and the higher natural abundance of 13C cf. 15N, which limits the period of measurement due to isotope dilution, and hence an assessment of the long-term contribution of direct uptake to the N economy of plant communities. [ABSTRACT FROM AUTHOR]
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- 2021
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12. On the Structure of Instantaneous Radiative Forcing Kernels for Greenhouse Gases.
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MAYCOCK, AMANDA C., SMITH, CHRISTOPHER J., RAP, ALEXANDRU, and RUTHERFORD, OWAIN
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RADIATIVE forcing , *GREENHOUSE gases , *RADIATIVE transfer , *EARTH temperature , *WATER vapor , *ALTITUDES - Abstract
The Suite of Community Radiative Transfer Codes Based on Edwards and Slingo (SOCRATES) offline radiative transfer code is used to investigate the magnitude and structure of the instantaneous radiative forcing kernels (IRFKs) for five major greenhouse gases (GHGs; CO2, CH4, N2O, CFC-11, and O3). All gases produce IRFKs that peak in the tropical upper troposphere. In addition to differences in spectroscopic intensities and the position of absorption features relative to the peak of the Planck function for Earth’s temperature, the variation in current background concentration of gases substantially affects the IRFK magnitudes. When the background concentration of CO2 is reduced from parts per million to parts per trillion levels, the peak magnitude of the IRFK increases by a factor of 642. When all gases are set to parts per trillion concentrations in the troposphere, the peak IRFK magnitudes are 1.0, 3.0, 3.1, 58, and 75Wm-2 ppmv-1 (100 hPa)-1 for CH4, CO2, N2O, O3, and CFC-11, respectively. The altitude of the IRFK maximum also differs, with the maximum for CFC-11 and water vapor occurring above 100 hPa whereas the other gases peak near 150–200 hPa. Overlap with water vapor absorption decreases the magnitude of the IRFKs for all of the GHGs, particularly in the lower-to-middle troposphere, but it does not strongly affect the peak IRFK altitude. Cloud radiative effects reduce the magnitude of the IRFK for CO2 by around 10%–20% in the upper troposphere. The use of IRFKs to estimate instantaneous radiative forcing is found to be accurate for small-amplitude perturbations but becomes inaccurate for large-amplitude changes (e.g., a doubling) for gases with a higher atmospheric optical depth. [ABSTRACT FROM AUTHOR]
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- 2021
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13. Large Variations in Volcanic Aerosol Forcing Efficiency Due to Eruption Source Parameters and Rapid Adjustments.
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Marshall, Lauren R., Smith, Christopher J., Forster, Piers M., Aubry, Thomas J., Andrews, Timothy, and Schmidt, Anja
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EXPLOSIVE volcanic eruptions , *STRATOSPHERIC aerosols , *RADIATIVE forcing , *AEROSOLS , *SULFATE aerosols , *SURFACE of the earth - Abstract
The relationship between volcanic stratospheric aerosol optical depth (SAOD) and volcanic radiative forcing is key for quantifying volcanic climate impacts. In their Fifth Assessment Report, the Intergovernmental Panel on Climate Change used one scaling factor between volcanic SAOD and volcanic forcing based on climate model simulations of the 1991 Mt. Pinatubo eruption, which may not be appropriate for all eruptions. Using a large ensemble of aerosol‐chemistry‐climate simulations of eruptions with different sulfur dioxide emissions, latitudes, emission altitudes, and seasons, we find that the effective radiative forcing (ERF) is on average 20% less than the instantaneous radiative forcing, predominantly due to a positive shortwave cloud adjustment. In our model, the volcanic SAOD‐ERF relationship is non‐unique and varies widely depending on time since an eruption, eruption latitude, and season due to differences in aerosol dispersion and incoming solar radiation. Our revised SAOD‐ERF relationships suggest that volcanic forcing has been previously overestimated. Plain Language Summary: Powerful explosive volcanic eruptions inject sulfur gases high into the atmosphere where they form a layer of sulfate aerosol particles that scatter sunlight back into space, decrease the transparency of the atmosphere, and cause surface cooling. The amount of sunlight that is scattered depends on the location of the layer of particles and particle size. We have used a complex climate model to quantify how eruptions of different magnitudes and occurring in different seasons and locations may affect the climate. We find that the relationship between the transparency of the atmosphere and the resulting climatic impact caused by volcanic sulfate aerosol particles depends on the amount of sunlight and the spread of the aerosol and therefore the time since the eruption, the eruption location, and the season. Our simulations also show that the eruptions reduce the cooling effect of clouds, which reduces the overall effectiveness of volcanoes at cooling the Earth's surface. Key Points: The relationship between volcanic SAOD and ERF depends on the time after an eruption, the eruption latitude, and eruption seasonRapid adjustments reduce the volcanic forcing by an average of 20% predominantly due to a positive shortwave cloud adjustmentWe provide a range of global mean volcanic SAOD to global mean ERF conversions dependent on eruption source parameters [ABSTRACT FROM AUTHOR]
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- 2020
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14. A Mixed-Methods Evaluation of Medical Residents' Attitudes Towards Interprofessional Learning and Stereotypes Following Sonography Student-Led Point-of-Care Ultrasound Training.
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Smith, Christopher J., Matthias, Tabatha, Beam, Elizabeth, Wampler, Kathryn, Pounds, Lea, Nickol, Devin, Shope, Ronald J., Carlson, Kristy, and Michael, Kimberly
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ATTITUDE (Psychology) , *RESIDENTS (Medicine) , *INTERPROFESSIONAL education , *DIAGNOSTIC ultrasonic imaging , *ULTRASONIC imaging , *GRADUATE medical education - Abstract
Background: Point-of-care ultrasound (POCUS) training is growing across internal medicine graduate medical education, but lack of trained faculty is a barrier to many programs. Interprofessional education (IPE) may offer a solution but must overcome potential biases of trainees. Aim: To evaluate the impact of an interprofessional POCUS training on residents' attitudes towards interprofessional learning and stereotypes. Setting: Midwestern health sciences university. Participants: Diagnostic medical sonography (DMS) students (n = 13) served as teachers for first-year internal medicine residents (IMR) (n = 49). Program Description: DMS students participated in a train-the-trainer session to learn teaching strategies via case-based simulation, then coached IMR to acquire images of the kidneys, bladder, and aorta on live models. Program Evaluation: Mixed-methods evaluation, including pre-/post-surveys and focus group interviews. The survey response rate was 100% (49/49 IMR). Composite survey scores evaluating residents' attitudes towards IPE and stereotyping of sonographers improved significantly following the intervention. Qualitative analysis of focus group interviews yielded four themes: enhanced respect for other disciplines, implications for future practice, increased confidence of DMS students, and interest in future IPE opportunities. Discussion: Interprofessional POCUS education can improve residents' perceptions towards IPE, increase their level of respect for sonographers, and motivate interest in future interprofessional collaboration. [ABSTRACT FROM AUTHOR]
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- 2020
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15. Grain legumes in crop rotations under low and variable rainfall: are observed short-term N benefits sustainable?
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Smith, Christopher J. and Chalk, Phillip M.
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LEGUMES , *GRAIN , *CROP rotation , *CROPPING systems , *RAINFALL , *GRAIN yields , *TIME measurements - Abstract
Increased grain yields are frequently obtained when a cereal follows a grain legume in sequence compared with a cereal-cereal rotation. The biotic (disease break) and abiotic (N supply) components of the observed benefits are identified and methods for differentiating the components are discussed. Annual measurements of the N balance of grain legume-cereal rotations are extremely variable when measured over short time periods and are therefore not useful as indicators of cropping system N sustainability. While measurement of long-term changes in total soil N is a valid index of N sustainability, this approach is impractical. We suggest an alternative avenue for the assessment of N sustainability by using simulation modelling, after validation, which takes climatic and biophysical parameters into account. [ABSTRACT FROM AUTHOR]
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- 2020
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16. The HadGEM3-GA7.1 radiative kernel: the importance of a well-resolved stratosphere.
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Smith, Christopher J., Kramer, Ryan J., and Sima, Adriana
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GENERAL circulation model , *STRATOSPHERE , *ATMOSPHERIC models , *RADIATIVE forcing , *OZONE layer , *STRATOCUMULUS clouds - Abstract
We present top-of-atmosphere and surface radiative kernels based on the atmospheric component (GA7.1) of the HadGEM3 general circulation model developed by the UK Met Office. We show that the utility of radiative kernels for forcing adjustments in idealised CO2 perturbation experiments is greatest where there is sufficiently high resolution in the stratosphere in both the target climate model and the radiative kernel. This is because stratospheric cooling to a CO2 perturbation continues to increase with height, and low-resolution or low-top kernels or climate model output are unable to fully resolve the full stratospheric temperature adjustment. In the sixth phase of the Coupled Model Intercomparison Project (CMIP6), standard atmospheric model data are available up to 1 hPa on 19 pressure levels, which is a substantial advantage compared to CMIP5. We show in the IPSL-CM6A-LR model where a full set of climate diagnostics are available that the HadGEM3-GA7.1 kernel exhibits linear behaviour and the residual error term is small, as well as from a survey of kernels available in the literature that in general low-top radiative kernels underestimate the stratospheric temperature response. The HadGEM3-GA7.1 radiative kernels are available at https://doi.org/10.5281/zenodo.3594673. [ABSTRACT FROM AUTHOR]
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- 2020
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17. The HadGEM3-GA7.1 radiative kernel: the importance of a well-resolved stratosphere.
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Smith, Christopher J., Kramer, Ryan J., and Sima, Adriana
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RADIATIVE forcing , *ATMOSPHERIC models , *STRATOSPHERE , *GENERAL circulation model , *GREENHOUSE gases - Abstract
We present top-of-atmosphere and surface radiative kernels based on the atmospheric component (GA7.1) of the HadGEM3 general circulation model developed by the UK Met Office. We show that the utility of radiative kernels for forcing adjustments in idealised CO2 perturbation experiments is most appropriate where there is sufficiently high resolution in the stratosphere in both the target climate model and the radiative kernel. This is because stratospheric cooling to a CO2 perturbation continues to increase with height, and low-resolution or low-top kernels or climate model output are unable to fully resolve the full stratospheric temperature adjustment. In the sixth phase of the Coupled Model Intercomparison Project (CMIP6), standard atmospheric model data is available up to 1hPa on 19 pressure levels, which is a substantial advantage compared to CMIP5. We show in the IPSL-CM6A-LR model where a full set of climate diagnostics are available that the HadGEM3-GA7.1 kernel exhibits linear behaviour and the residual error term is small. From kernels available in the literature we recommend three kernels for adjustment calculations to CO2 and well-mixed greenhouse gas perturbations based on their stratospheric resolution: HadGEM3-GA7.1, ECMWF-Oslo, and ECHAM6. The HadGEM3-GA7.1 radiative kernels are available at https://doi.org/10.5281/zenodo.3594673 (Smith, 2019). [ABSTRACT FROM AUTHOR]
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- 2020
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18. Elastic response of a nematic liquid crystal to an immersed nanowire.
- Author
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Smith, Christopher J. and Denniston, Colin
- Subjects
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HYDRODYNAMICS , *FERROMAGNETIC materials , *NANOWIRES , *NEMATOCIDES , *NANOSTRUCTURED materials , *ELASTIC analysis (Engineering) , *MAXWELL-Boltzmann distribution law - Abstract
We study the immersion of a ferromagnetic nanowire within a nematic liquid crystal using a lattice Boltzmann algorithm to solve the full three-dimensional equations of hydrodynamics. We present an algorithm for including a moving boundary, to simulate a nanowire, in a lattice Boltzmann simulation. The nematic imposes a torque on a wire that increases linearly with the angle between the wire and the equilibrium direction of the director field. By rotation of these nanowires, one can determine the elastic constants of the nematic. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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19. Laser preparation and probing of initial and final orbital alignment in collision-induced energy transfer Ca(4s5p, 1P1) +He→Ca(4s5p, 3P2)+He.
- Author
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Smith, Christopher J., Driessen, Jan P. J., Eno, Larry, and Leone, Stephen R.
- Subjects
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ENERGY transfer , *CALCIUM , *HELIUM - Abstract
In a crossed beam atomic energy transfer experiment, relative cross sections are measured between initial and final magnetic substates of atomic orbitals in a three vector correlation experiment. A pulsed laser beam prepares Ca(4s5p 1P1) in a single magnetic sublevel |j1mi> with respect to the laser polarization vector. Subsequent collision with He at a well-defined relative velocity yields Ca(4s5p 3P2). The near-resonant Ca(4s5p 3P2) is probed by a second polarized pulsed laser, revealing its magnetic sublevel |j2mf> distribution with respect to the probe laser polarization vector. The experiment is analyzed in the collision frame where the direction of the initial relative velocity vector serves as the quantization axis. In this frame, the initial and final Ca states are characterized by substates |j1m1> and |j2m2>, respectively. Fourteen collision frame cross sections are needed to describe the energy transfer completely. Eight of these cross sections are real and positive (conventional type—describing population transfer) and six are complex (coherence type—containing phase information). By symmetry, only 15 unique parameters for the real and imaginary parts of the cross sections are required, nine of which are obtained here using linear polarizations and collinear laser beams.Possible cases for circularly polarized light are also tabulated; measurement of these cases would provide several more parameters. For initial parallel preparation of the 1P1 p orbital with respect to the relative velocity (m1=0), the final 3P2 state is highly aligned in the m2=±1 and m2=±2 sublevels. Initial preparation of the p orbital perpendicular to the relative velocity vector (m1=±1) produces an aligned 3P2 state with greater population in the m2=0 and m2=±1 sublevels compared to the m2=±2 sublevels. Using the coherence information and symmetry, orientation cross sections are obtained into the m2=±1 sublevels (i.e., m preserving... [ABSTRACT FROM AUTHOR]
- Published
- 1992
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20. Relating benthic sensitivity and status to spatial distribution and intensity of trawling in the Eastern Mediterranean.
- Author
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Smith, Christopher J., Papadopoulou, Nadia K., Maina, Irida, Kavadas, Stefanos, van Denderen, P. Daniel, Katsiaras, Nikolaos, Reizopoulou, Sofia, Karakassis, Ioannis, Tselepides, Anastasios, and Tsikopoulou, Irini
- Subjects
- *
DREDGING (Fisheries) , *TRAWLING , *FISHERY management , *ENVIRONMENTAL protection , *OCEAN bottom , *BIOMASS - Abstract
[Display omitted] • Environmental protection linked to EU policy implementation requires benthic status assessments at the habitat level. • Bottom trawling operates over many habitats but with different intensity. • Relative benthic status values were above the threshold of 0.95 for all habitats analysed. • The assessment allows us to identify areas and habitats that are most at risk, and to prioritize management actions. The ecosystem approach to fisheries management needs information of not just where bottom trawlers operate but also on their impact on the seabed, which is also highly relevant to the EU Marine Strategy Framework Directive (MSFD) Descriptor D6, seafloor integrity. In this study, we assess the benthic impact of bottom trawling in the Eastern Mediterranean in areas primarily fished by the Greek fleet. Seabed habitat sensitivity was modelled using macrofaunal longevity and biomass relationship based on data from more than 800 locations, representing 9 MSFD benthic habitats, and benthic status was assessed using the relative benthic status indicator. The pressure of seabed trawling was higher in circalittoral mud and circalittoral sand habitats showing a heterogeneous distribution pattern with intensive trawling in localized areas mainly coastal. Benthic status was high for all habitats reflecting the low trawling intensity and impact in most of the study area compared to other regions of Mediterranean or European waters. The results constitute the benchmark for benthic status in relation to trawling intensity in Eastern Mediterranean allowing to identify regions that are most at risk, and to prioritize management actions. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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21. Historical Changes and Reasons for Model Differences in Anthropogenic Aerosol Forcing in CMIP6.
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Fiedler, Stephanie, van Noije, Twan, Smith, Christopher J., Boucher, Olivier, Dufresne, Jean‐Louis, Kirkevåg, Alf, Olivié, Dirk, Pinto, Rovina, Reerink, Thomas, Sima, Adriana, and Schulz, Michael
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- *
AEROSOLS , *EFFECT of human beings on climate change , *MINERAL dusts , *RADIATIVE forcing , *GREENHOUSE gases , *OCEAN color - Abstract
The Radiative Forcing Model Intercomparison Project (RFMIP) allows estimates of effective radiative forcing (ERF) in the Coupled Model Intercomparison Project phase six (CMIP6). We analyze the RFMIP output, including the new experiments from models that use the same parameterization for anthropogenic aerosols (RFMIP‐SpAer), to characterize and better understand model differences in aerosol ERF. We find little changes in the aerosol ERF for 1970–2014 in the CMIP6 multi‐model mean, which implies greenhouse gases primarily explain the positive trend in the total anthropogenic ERF. Cloud‐mediated effects dominate the present‐day aerosol ERF in most models. The results highlight a regional increase in marine cloudiness due to aerosols, despite suppressed cloud lifetime effects in that RFMIP‐SpAer experiment. Negative cloud‐mediated effects mask positive direct effects in many models, which arise from strong anthropogenic aerosol absorption. The findings suggest opportunities to better constrain simulated ERF by revisiting the optical properties and long‐range transport of aerosols. Plain Language Summary: Aerosols are particles in the atmosphere with sizes ranging from nanometers to tens of micrometers, which are emitted by natural and anthropogenic processes or formed from gases in the atmosphere. The extent to which anthropogenic aerosols affect the radiation budget of Earth is important to better understand anthropogenic climate changes. Aerosol effects on the radiation budget are simulated by complex Earth system models that informed the Sixth Assessment Report of the Intergovernmental Panel on Climate Change. Our study addresses why such model experiments show different magnitudes for aerosol radiative effects. The results point to opportunities to further improve models with existing observations of aerosol optical properties and aerosol transport over oceans in addition to the much‐studied aerosol effects on clouds. Key Points: Coupled Model Intercomparison Project phase six (CMIP6) averaged trend in aerosol effective radiative forcing (ERF) is small for 1970–2014 and weakly positive for 2000–2014Positive direct aerosol radiative effects in CMIP6 models are associated with strong aerosol absorptionDiverse and often strong cloud‐mediated effects primarily determine the magnitude of aerosol ERF in CMIP6 [ABSTRACT FROM AUTHOR]
- Published
- 2023
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22. FAIR v1.3: a simple emissions-based impulse response and carbon cycle model.
- Author
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Smith, Christopher J., Forster, Piers M., Allen, Myles, Leach, Nicholas, Millar, Richard J., Passerello, Giovanni A., and Regayre, Leighton A.
- Subjects
- *
CARBON cycle , *ATMOSPHERIC models , *RADIATIVE forcing , *ATMOSPHERIC temperature , *GREENHOUSE gases & the environment - Abstract
Simple climate models can be valuable if they are able to replicate aspects of complex fully coupled earth system models. Larger ensembles can be produced, enabling a probabilistic view of future climate change. A simple emissions-based climate model, FAIR, is presented, which calculates atmospheric concentrations of greenhouse gases and effective radiative forcing (ERF) from greenhouse gases, aerosols, ozone and other agents. Model runs are constrained to observed temperature change from 1880 to 2016 and produce a range of future projections under the Representative Concentration Pathway (RCP) scenarios. The constrained estimates of equilibrium climate sensitivity (ECS), transient climate response (TCR) and transient climate response to cumulative CO2 emissions (TCRE) are 2.86 (2.01 to 4.22) K, 1.53 (1.05 to 2.41)K and 1.40 (0.96 to 2.23)K (1000 GtC)-1 (median and 5-95% credible intervals). These are in good agreement with the likely Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) range, noting that AR5 estimates were derived from a combination of climate models, observations and expert judgement. The ranges of future projections of temperature and ranges of estimates of ECS, TCR and TCRE are somewhat sensitive to the prior distributions of ECS=TCR parameters but less sensitive to the ERF from a doubling of CO2 or the observational temperature dataset used to constrain the ensemble. Taking these sensitivities into account, there is no evidence to suggest that the median and credible range of observationally constrained TCR or ECS differ from climate model-derived estimates. The range of temperature projections under RCP8.5 for 2081-2100 in the constrained FAIR model ensemble is lower than the emissions-based estimate reported in AR5 by half a degree, owing to differences in forcing assumptions and ECS=TCR distributions. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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23. The residual value of fertiliser N in crop sequences: An appraisal of 60 years of research using 15N tracer.
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Smith, Christopher J. and Chalk, Phillip M.
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NITROGEN fertilizers , *CROP rotation , *ORGANIC fertilizers , *SLURRY , *CROP management - Abstract
Over the past 60 years, more than 100 experiments have been conducted using manufactured and organic fertilisers labelled with the stable isotope 15 N. Organic N forms included crop residues, green manures, composts, animal manures and slurries in either crop sequences or successive cuttings of pasture grasses. As stated in the pioneering paper of Low and Piper (1957), the use of 15 N-labelled materials is essential to follow the dynamics of fertiliser N in the soil-plant system. The majority of studies used 15 N-labelled manufactured fertilisers. In general there was no difference of N fertiliser form on the 15 N recovery in the 1st residual crop (R 1 ) and in subsequent crops (R 2 , R 3 , R n …). The 15 N recovery was <10% of added N in the R 1 crop and less in subsequent crops (R 2 , R 3 ), with the exception of studies where severe water stress limited crop growth in the year of N application (Yr 0 ). High mineral N remained in the root zone which was assimilated by the subsequent crops, giving a higher residual value in the R 1 crop than was normally observed. The similarity of the results from more than 100 studies, and a boot strapping analysis, suggested that dilution of the 15 N by the large unlabelled mineralisable soil organic N pool compromises the use of the techniques to explore residual uptake of immobilised 15 N. The isotope technique does, however, enable researchers to monitor the rate of incorporation of the N into microbial biomass and more recalcitrant organic N forms within the soil organic matter. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
24. Evaluation of a Novel Handoff Communication Strategy for Patients Admitted from the Emergency Department.
- Author
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Smith, Christopher J., Buzalko, Russell J., Anderson, Nathan, Michalski, Joel, Warchol, Jordan, Ducey, Stephen, and Branecki, Chad E.
- Subjects
- *
ACADEMIC medical centers , *COMMUNICATION , *CONVERSATION , *HOSPITAL admission & discharge , *HOSPITAL emergency services , *MEDICAL appointments , *MEDICAL care , *MEDICAL quality control , *MEDICAL records , *MEDICAL transcription , *MEDICAL practice , *PATIENTS , *PSYCHOLOGY of physicians , *PROBABILITY theory , *QUALITY assurance , *QUESTIONNAIRES , *SURVEYS , *TIME , *TREATMENT effectiveness , *PRE-tests & post-tests - Abstract
Introduction: Miscommunication during inter-unit handoffs between emergency and internal medicine physicians may jeopardize patient safety. Our goal was to evaluate the impact of a structured communication strategy on the quality of admission handoffs. Methods: We conducted a mixed-methods, pre-test/post-test study at a 560-bed academic health center with 60,000 emergency department (ED) patient visits per year. Admission-handoff best practices were integrated into a modified SBAR format, resulting in the Situation, Background, Assessment, Responsibilities & Risk, Discussion & Disposition, Read-back & Record (SBAR-DR) model. Physician handoff conversations were recorded and transcribed for the 60 days before (n=110) and 60 days after (n=110) introduction of the SBAR-DR strategy. Transcriptions were scored by two blinded physicians using a 16-item scoring instrument. The primary outcome was the composite handoff quality score. We assessed physician perceptions via a post-intervention survey. Results: The composite quality score improved in the post-intervention phase (7.57 + 2.42 vs. 8.45 + 2.51, p=.0085). Three of the 16 individual scoring elements also improved, including time for questions (70.6% vs. 82.7%, p=.0344) and confirmation of disposition plan (41.8% vs. 62.7%, p=.0019). The majority of emergency and internal medicine physicians felt that the SBAR-DR model had a positive impact on patient safety and handoff efficiency. Conclusion: Implementation of the SBAR-DR strategy resulted in improved verbal handoff quality. Agreement upon a clear disposition plan was the most improved element, which is of great importance in delineating responsibility of care and streamlining ED throughput. Future efforts should focus on nurturing broader physician buy-in to facilitate institution-wide implementation. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
25. FAIR v1.1: A simple emissions-based impulse response and carbon cycle model.
- Author
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Smith, Christopher J., Forster, Piers M., Allen, Myles, Leach, Nicholas, Millar, Richard J., Passerello, Giovanni A., and Regayre, Leighton A.
- Subjects
- *
ATMOSPHERIC models , *GREENHOUSE gases , *ATMOSPHERIC aerosols - Abstract
Simple climate models can be valuable if they are able to replicate aspects of complex fully coupled earth system models. Larger ensembles can be produced, enabling a probabilistic view of future climate change. A simple emissions-based climate model, FAIR, is presented which calculates atmospheric concentrations of greenhouse gases and effective radiative forcing (ERF) from greenhouse gases, aerosols, ozone precursors and other agents. The ERFs are integrated into global mean surface temperature change. Model runs are constrained to observed temperature change from 1880 to 2016 and produce a range of future projections under the Representative Concentration Pathway (RCP) scenarios. For the historical period the ERF time series in FAIR emulates the results in the IPCC Fifth Assessment Report (AR5), whereas for RCP historical and future scenarios, the greenhouse gas concentrations in FAIR closely track the observations and projections in the RCPs. The constrained estimates of equilibrium climate sensitivity (ECS) of 2.79 (1.97 to 4.08) K, transient climate response (TCR) of 1.47 (1.03 to 2.23) K and transient climate response to cumulative CO2 emissions (TCRE) of 1.43 (1.01 to 2.16) K (1000 GtC)-1 (median and 5-95 % credible intervals) are in good agreement, with tighter uncertainty bounds, than AR5 (1.5 to 4.5 K, 1.0 to 2.5 K, and 0.8 to 2.5 K respectively). The ranges of future projections of temperature and ranges of estimates of ECS, TCR and TCRE are moderately sensitive to the historical temperature dataset used to constrain, prior distributions of ECS/TCR parameters, aerosol radiative forcing relationship and ERF from a doubling of CO2. Taking these sensitivities into account, there is no evidence to suggest that the median and credible range of observationally constrained TCR or ECS differ from climate model-derived estimates. However, the range of temperature projections under the RCP scenarios for 2081-2100 in the constrained FAIR model ensemble are lower than the emissions-based estimates reported in AR5. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
26. Impacts of Stratospheric Sulfate Geoengineering on Global Solar Photovoltaic and Concentrating Solar Power Resource.
- Author
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Smith, Christopher J., Crook, Julia A., Crook, Rolf, Jackson, Lawrence S., Osprey, Scott M., and Forster, Piers M.
- Subjects
- *
PHOTOVOLTAIC power systems , *SOLAR energy , *ENVIRONMENTAL engineering , *GREENHOUSE gas mitigation , *CLIMATE change - Abstract
In recent years, the idea of geoengineering, artificially modifying the climate to reduce global temperatures, has received increasing attention because of the lack of progress in reducing global greenhouse gas emissions. Stratospheric sulfate injection (SSI) is a geoengineering method proposed to reduce planetary warming by reflecting a proportion of solar radiation back into space that would otherwise warm the surface and lower atmosphere. The authors analyze results from the Met Office Hadley Centre Global Environment Model, version 2, Carbon Cycle Stratosphere (HadGEM2-CCS) climate model with stratospheric emissions of 10 Tg yr−1 of SO2, designed to offset global temperature rise by around 1°C. A reduction in concentrating solar power output of 5.9% on average over land is shown under SSI relative to a baseline future climate change scenario (RCP4.5) caused by a decrease in direct radiation. Solar photovoltaic energy is generally less affected as it can use diffuse radiation, which increases under SSI, at the expense of direct radiation. The results from HadGEM2-CCS are compared with the Goddard Earth Observing System Chemistry-Climate Model (GEOSCCM) from the Geoengineering Model Intercomparison Project (GeoMIP), with 5 Tg yr−1 emission of SO2. In many regions, the differences predicted in solar energy output between the SSI and RCP4.5 simulations are robust, as the sign of the changes for both HadGEM2-CCS and GEOSCCM agree. Furthermore, the sign of the total and direct annual mean radiation changes evaluated by HadGEM2-CCS agrees with the sign of the multimodel mean changes of an ensemble of GeoMIP models over the majority of the world. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
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27. Investigating the accuracy of a novel telehealth diagnostic approach for autism spectrum disorder.
- Author
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Smith, Christopher J., Rozga, Agata, Matthews, Nicole, Oberleitner, Ron, Nazneen, Nazneen, and Abowd, Gregory
- Subjects
- *
PSYCHOLOGY periodicals , *AUTISM spectrum disorders , *TELEMEDICINE , *CHILD development , *CHILD behavior , *PARENTS , *RESEARCH funding , *VIDEO recording , *CASE-control method ,RESEARCH evaluation - Abstract
Research indicates that a substantial amount of time elapses between parents' first concerns about their child's development and a formal diagnosis of autism spectrum disorder (ASD). Telehealth presents an opportunity to expedite the diagnostic process. This project compared a novel telehealth diagnostic approach that utilizes clinically guided in-home video recordings to the gold standard in-person diagnostic assessment. Participants included 40 families seeking an ASD evaluation for their child and 11 families of typically developing children. Children were between the ages of 18 months and 6 years 11 months; mean adaptive behavior composite = 75.47 (SD = 15.94). All parent participants spoke English fluently. Families completed the Naturalistic Observation Diagnostic Assessment (NODA) for ASD, which was compared to an in-person assessment (IPA). Agreement between the 2 methods, as well as sensitivity, specificity, and interrater reliability, were calculated for the full sample and the subsample of families seeking an ASD evaluation. Diagnostic agreement between NODA and the IPA was 88.2% (κ = 0.75) in the full sample and 85% (κ = 0.58) in the subsample. Sensitivity was 84.9% in both, whereas specificity was 94.4% in the full sample and 85.7% in the subsample. Kappa coefficients for interrater reliability indicated 85% to 90% accuracy between raters. NODA utilizes telehealth technology for families to share information with professionals and provides a method to inform clinical judgment for a diagnosis of ASD. Due to the high level of agreement with the IPA in this sample, NODA has potential to improve the efficiency of the diagnostic process for ASD. (PsycINFO Database Record [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
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28. Cloud cover effect of clear-sky index distributions and differences between human and automatic cloud observations.
- Author
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Smith, Christopher J., Bright, Jamie M., and Crook, Rolf
- Subjects
- *
CLOUDINESS , *PHOTOVOLTAIC cells , *PHOTOVOLTAIC effect , *SOLAR ponds , *SPECTRAL irradiance - Abstract
The statistics of clear-sky index can be used to determine solar irradiance when the theoretical clear sky irradiance and the cloud cover are known. In this paper, observations of hourly clear-sky index for the years of 2010–2013 at 63 locations in the UK are analysed for over 1 million data hours. The aggregated distribution of clear-sky index is bimodal, with strong contributions from mostly-cloudy and mostly-clear hours, as well as a lower number of intermediate hours. The clear-sky index exhibits a distribution of values for each cloud cover bin, measured in eighths of the sky covered (oktas), and also depends on solar elevation angle. Cloud cover is measured either by a human observer or automatically with a cloud ceilometer. Irradiation (time-integrated irradiance) values corresponding to human observations of “cloudless” skies (0 oktas) tend to agree better with theoretical clear-sky values, which are calculated with a radiative transfer model, than irradiation values corresponding to automated observations of 0 oktas. It is apparent that the cloud ceilometers incorrectly categorise more non-cloudless hours as cloudless than human observers do. This leads to notable differences in the distributions of clear-sky index for each okta class, and between human and automated observations. Two probability density functions—the Burr (type III) for mostly-clear situations, and generalised gamma for mostly-cloudy situations—are suggested as analytical fits for each cloud coverage, observation type, and solar elevation angle bin. For human observations of overcast skies (8 oktas) where solar elevation angle exceeds 10°, there is no significant difference between the observed clear-sky indices and the generalised gamma distribution fits. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
29. An all-sky radiative transfer method to predict optimal tilt and azimuth angle of a solar collector.
- Author
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Smith, Christopher J., Forster, Piers M., and Crook, Rolf
- Subjects
- *
RADIATIVE transfer , *AZIMUTH , *SOLAR collectors , *CLOUDS , *WATER vapor , *IRRADIATION - Abstract
This paper describes a radiative transfer method for calculating radiances in all-sky conditions and performing an integration over the view hemisphere of an arbitrary plane to calculate tilted irradiance. The advantage of this method is the combination of cloud parameters inside the radiative transfer model with a tilt procedure. For selected locations this method is applied with cloud, ozone, water vapour and aerosol input data to determine tilted irradiance, horizontal irradiance and optimal tilt angle. A validation is performed for horizontal and tilted irradiance against high-quality pyranometer data. For 27 sites around the world, the annual horizontal irradiation predicted by our model had a mean bias difference of +0.56% and a root-mean-squared difference of 6.69% compared to ground measurements. The difference between the annual irradiation estimates from our model and the measurements from one site that provides tilted irradiance were within ±6% for all orientations except the north-facing vertical plane. For European and African sites included in the validation, the optimal tilt from our model is typically a few degrees steeper than predictions from the popular PVGIS online tool. Our model is generally applicable to any location on the earth’s surface as the satellite cloud and atmosphere data and aerosol climatology data are available globally. Furthermore, all of the input data are standard variables in climate models and so this method can be used to predict tilted irradiance in future climate experiments. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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30. A Tale of Two Cities: Akimbo Body Theatrics in Bristol, England, and Spanish Town, Jamaica.
- Author
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SMITH, CHRISTOPHER J.
- Subjects
- *
BODY language , *MINSTREL music , *CREOLES , *WORKING class ,DANCE performance - Abstract
The article offers information on the integration of the akimbo body language in theatrical minstrelsy between Bristol, England and Spanish Town, Jamaica. Topics include the tension exists between the embodiment of the working-class and the elites during creole festivals, the creolizing body vocabulary found in the novel "Salmagundi," and the short story "The Legend of Sleepy Hollow," and the appearance of transgressive connotation and irruptive conduct during creolized dance performances.
- Published
- 2015
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31. Handoff Training for Medical Students: Attitudes, Knowledge, and Sustainability of Skills.
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Smith, Christopher J., Peterson, Grant, and Beck, Gary L.
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- *
MEDICAL students , *CLINICAL medicine research , *MEDICAL education - Abstract
Introduction: The medical community has placed increasing emphasis on ensuring quality patient care handoffs, yet there is relatively little research regarding educational interventions for medical students. Objective: To assess the impact of a handoff communication workshop on senior medical students' attitudes, knowledge, and skills. Method: A 3-hour handoff skills workshop was developed using published research and educational models. The session included didactic lectures, role-play activities, and group discussion. We assessed the workshop's impact using attitudinal, fact-based multiple choice, and case-based questions preceding, immediately following, and several months after the intervention. Result: From 2013-2014, 59 students participated in the handoff training, with 56 (95%) completing the pre- and post-tests. Participants' self-reported attitudes improved following the intervention (p≤.005 in 12 of 13 questions). The mean number of correct answers on multiple choice questions increased from 6.75 (CI 6.44-7.05) to 8.47 (CI 8.28-8.67) out of 9 (p<.001). Vignette scores improved from 6.00 to 8.14 out of 10 (p<0.001). Thirty-six participants (61%) completed the pre-, post-, and follow-up vignettes. Post-workshop vignette scores improved significantly (6.28 vs. 8.19, p<.001), but decreased in follow-up testing (8.19 vs. 6.97, p=.008). Conclusion: The handoff workshop improved participants' attitudes, knowledge, and skills, but performance gains declined in the months following training. These findings suggest that handoff training should coincide with the opportunity to apply these skills in a clinical context. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
32. A Method for Universal Screening of Elementary School Students: Development of the Social Challenges Screening Questionnaire.
- Author
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Smith, Christopher J., Pollard, Elena, Stein, Alexander J., Ober-Reynolds, Sharman, Kirwan, Janet, Malligo, Amanda, Matthews, Nicole L., Openden, Daniel, and Melmed, Raun D.
- Subjects
- *
SCHOOL children , *ELEMENTARY schools , *QUESTIONNAIRES , *HEARING impaired children , *ACADEMIC programs , *PSYCHOLOGY of learning - Abstract
Schools regularly screen students for hearing and vision impairments because they present impediments to academic progress. For the same reason, schools should consider adding a universal screening for social challenges, which may also impede the learning process. This study reports on the development of the Social Challenges Screening Questionnaire (SCSQ), an efficient teacher-report screening questionnaire that identifies students with challenges who may benefit from a psychological evaluation. Further, the questionnaire may help identify students with Autism Spectrum Disorder who were previously undiagnosed. The SCSQ was administered to 549 general education students in the third and fourth grades. Internal consistency was.85. A smaller sample of students (n = 50) was selected for additional follow up assessment using the Social Responsiveness Questionnaire, Second Edition. Scores on the two instruments were strongly correlated (r =.87, p <.01), and sensitivity (.94) and specificity (.88) indicate the SCSQ can efficiently detect students with social challenges in need of a formal evaluation. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
33. Assessment of a Brief Handoff Skills Workshop for Incoming Interns: Do Past Handoff Experiences Impact Training Outcomes?
- Author
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Smith, Christopher J., Wadman, Michael C., Harrison, Jeffrey, and Beck, Gary L.
- Subjects
- *
PATIENTS , *MEDICAL care , *MEDICAL schools , *MEDICAL students , *RESIDENTS (Medicine) , *MEDICAL education - Abstract
BACKGROUND: Patient care handoffs are a core professional activity that incoming interns are expected to perform without direct supervision upon starting residency, yet training in medical schools is inconsistent. OBJECTIVE: To implement a brief handoff communication workshop for incoming interns and determine whether learner-level determinants were associated with differences in training outcomes. METHODS: We conducted a one-hour interactive handoff skills workshop for all incoming interns at a Midwestern academic medical center. We performed paired pre/post-intervention assessments of participants' attitudes and ability to perform representative handoff skills. The results were analyzed in aggregate and based upon participants' prior handoff experiences using Wilcoxon signed-rank test. RESULTS: Ninety-nine of 108 interns (91.7%) completed both pre- and post-surveys. There was significant improvement in all 10 attitude-based questions (P ≤ 0.014 for all) and on the skills assessment (1.07 vs 2.16 on 0-4 point scale, SD 1.25, P < 0.001). Results remained significant regardless of prior training, number of handoffs observed, number of handoffs performed, medical school, or residency discipline. CONCLUSION: A brief interactive workshop for incoming interns can improve participants' confidence and performance of basic handoff skills, regardless of previous training or experience. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
34. Global analysis of photovoltaic energy output enhanced by phase change material cooling.
- Author
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Smith, Christopher J., Forster, Piers M., and Crook, Rolf
- Subjects
- *
PHOTOVOLTAIC power systems , *PHASE change materials , *COOLING , *PERFORMANCE evaluation , *MELTING , *TEMPERATURE effect - Abstract
Highlights: [•] Phase change materials (PCMs) can passively cool PV panels to increase energy output. [•] A global numerical analysis of PV energy output with PCM cooling is presented. [•] The most promising locations for PCM cooling are in the tropics. [•] A relative performance improvement of over 6% is possible in some regions. [•] A sub-optimal PCM melting temperature still produces a beneficial energy output enhancement. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
35. Vernix Caseosa Peritonitis Causing Acute Abdomen After Cesarean Section: A Case Series.
- Author
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Yang, Christina H. J., Eykman, Elizabeth N., Smith, Christopher J., Bacon, James, Morris, Jonathan M., Baber, Rodney J., and Seeho, Sean K. M.
- Subjects
- *
CESAREAN section , *ACUTE abdomen , *FOREIGN body reaction , *APPENDICITIS , *PERITONITIS , *PERITONEAL dialysis - Abstract
Objective: Rare disease Background: Vernix caseosa peritonitis (VCP) is a rare complication that typically presents following an otherwise uneventful cesarean section. Leakage of vernix caseosa into the peritoneum is thought to elicit a granulomatous foreign body reaction. Symptoms can be similar to other acute abdominal conditions, and diagnosis is confirmed by intraoperative findings and histological examination. Peritoneal lavage with supportive measures is the mainstay of treatment and recovery. Case Reports: Case 1 was a 30-year-old woman who developed right iliac fossa pain, fever, tachycardia, and tachypnea less than a week after her lower segment cesarean section (LSCS). She underwent a laparoscopy for a peritonitic abdomen and concern for intra-abdominal sepsis. A peritoneal biopsy demonstrated histological changes consistent with VCP. Case 2 was a 39-year-old woman who underwent a LSCS. After discharge, she re-presented with generalized abdominal pain. With computed tomography (CT) scan findings suggestive of appendicitis, an appendectomy was performed, and vernix caseosa was detected in all quadrants. Case 3 was a 33-year-old woman who presented with fever, vomiting, diarrhea, and iliac fossa pain 9 days following an LSCS. She was given analgesia and antibiotics for a pelvic fluid collection noted on CT scan. She represented with tense swelling and pain above her cesarean section incision. Laparoscopy revealed adhesions over the lower abdomen and pelvis and white plaques suggestive of vernix caseosa along the peritoneal side walls. Conclusions: The rising incidence of cesarean births worldwide creates the potential for increased numbers of VCP cases. Greater recognition of VCP is warranted to prevent unnecessary procedures. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
36. The IPCC Sixth Assessment Report WGIII climate assessment of mitigation pathways: from emissions to global temperatures.
- Author
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Kikstra, Jarmo S., Nicholls, Zebedee R. J., Smith, Christopher J., Lewis, Jared, Lamboll, Robin D., Byers, Edward, Sandstad, Marit, Meinshausen, Malte, Gidden, Matthew J., Rogelj, Joeri, Kriegler, Elmar, Peters, Glen P., Fuglestvedt, Jan S., Skeie, Ragnhild B., Samset, Bjørn H., Wienpahl, Laura, van Vuuren, Detlef P., van der Wijst, Kaj-Ivar, Al Khourdajie, Alaa, and Forster, Piers M.
- Subjects
- *
CLIMATE change mitigation , *DOWNSCALING (Climatology) , *SCIENCE journalism , *RADIATIVE forcing , *PHYSICAL sciences - Abstract
While the Intergovernmental Panel on Climate Change (IPCC) physical science reports usually assess a handful of future scenarios, the Working Group III contribution on climate mitigation to the IPCC's Sixth Assessment Report (AR6 WGIII) assesses hundreds to thousands of future emissions scenarios. A key task in WGIII is to assess the global mean temperature outcomes of these scenarios in a consistent manner, given the challenge that the emissions scenarios from different integrated assessment models (IAMs) come with different sectoral and gas-to-gas coverage and cannot all be assessed consistently by complex Earth system models. In this work, we describe the "climate-assessment" workflow and its methods, including infilling of missing emissions and emissions harmonisation as applied to 1202 mitigation scenarios in AR6 WGIII. We evaluate the global mean temperature projections and effective radiative forcing (ERF) characteristics of climate emulators FaIRv1.6.2 and MAGICCv7.5.3 and use the CICERO simple climate model (CICERO-SCM) for sensitivity analysis. We discuss the implied overshoot severity of the mitigation pathways using overshoot degree years and look at emissions and temperature characteristics of scenarios compatible with one possible interpretation of the Paris Agreement. We find that the lowest class of emissions scenarios that limit global warming to "1.5 ∘ C (with a probability of greater than 50 %) with no or limited overshoot" includes 97 scenarios for MAGICCv7.5.3 and 203 for FaIRv1.6.2. For the MAGICCv7.5.3 results, "limited overshoot" typically implies exceedance of median temperature projections of up to about 0.1 ∘ C for up to a few decades before returning to below 1.5 ∘ C by or before the year 2100. For more than half of the scenarios in this category that comply with three criteria for being "Paris-compatible", including net-zero or net-negative greenhouse gas (GHG) emissions, median temperatures decline by about 0.3–0.4 ∘ C after peaking at 1.5–1.6 ∘ C in 2035–2055. We compare the methods applied in AR6 with the methods used for SR1.5 and discuss their implications. This article also introduces a "climate-assessment" Python package which allows for fully reproducing the IPCC AR6 WGIII temperature assessment. This work provides a community tool for assessing the temperature outcomes of emissions pathways and provides a basis for further work such as extending the workflow to include downscaling of climate characteristics to a regional level and calculating impacts. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
37. Examination of Clinical and Assessment Type Differences Between Toddlers with ASD from Multiplex and Simplex Families.
- Author
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Anbar, Joshua, Matthews, Nicole, James, Stephen, Ariff, Afzal, Pierce, Karen, and Smith, Christopher J.
- Subjects
- *
FAMILIES & psychology , *DIAGNOSIS of autism , *PARENTS , *MOTOR ability , *RESEARCH funding , *AUTISM , *FAMILIES , *SEVERITY of illness index , *PSYCHOLOGICAL adaptation , *DESCRIPTIVE statistics , *RESEARCH , *SPEECH evaluation , *PHENOTYPES , *COGNITION , *LANGUAGE acquisition , *EVALUATION , *CHILDREN - Abstract
Few studies have examined differences in autism spectrum disorder (ASD) phenotype between children from multiplex and simplex families at the time of diagnosis. The present study used an age- and gender-matched, community-based sample (n = 105) from the southwestern United States to examine differences in ASD symptom severity, cognitive development, and adaptive functioning. No significant differences between children from multiplex and simplex families were observed. Exploratory analysis revealed that parents underreported receptive and expressive language and fine motor skills compared to professional observation, especially among children from multiplex families. These findings suggest that diagnosticians may need to consider family structure when choosing and interpreting assessments of receptive language, expressive language, and fine motor skills. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
38. The ubiquitin ligase RNF126 regulates the retrograde sorting of the cation-independent mannose 6-phosphate receptor.
- Author
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Smith, Christopher J. and McGlade, C. Jane
- Subjects
- *
UBIQUITIN ligases , *MANNOSE 6-phosphate receptors , *GENETIC regulation , *PROTEASOMES , *ENDOPLASMIC reticulum , *SMALL interfering RNA - Abstract
Abstract: The ubiquitin proteasome system is central to the regulation of a number of intracellular sorting pathways in mammalian cells including quality control at the endoplasmic reticulum and the internalization and endosomal sorting of cell surface receptors. Here we describe that RNF126, an E3 ubiquitin ligase, is involved in the sorting of the cation-independent mannose 6-phosphate receptor (CI-MPR). In cells transiently depleted of RNF126, the CI-MPR is dispersed into Rab4 positive endosomes and the efficiency of retrograde sorting is delayed. Furthermore, the stable knockdown of RNF126 leads to the lysosomal degradation of CI-MPR and missorting of cathepsin D. RNF126 specifically regulates the sorting of the CI-MPR as other cargo that follow the retrograde sorting route including the cholera toxin, furin and TGN38 are unaffected in the absence of RNF126. Lastly we show that the RING finger domain of RNF126 is required to rescue the decrease in CI-MPR levels, suggesting that the ubiquitin ligase activity of RNF126 is required for CI-MPR sorting. Together, our data indicate that the ubiquitin ligase RNF126 has a role in the retrograde sorting of the CI-MPR [Copyright &y& Elsevier]
- Published
- 2014
- Full Text
- View/download PDF
39. The E3 ubiquitin ligases RNF126 and Rabring7 regulate endosomal sorting of the epidermal growth factor receptor.
- Author
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Smith, Christopher J., Berry, Donna M., and McGlade, C. Jane
- Subjects
- *
UBIQUITIN ligases , *ENDOSOMES , *EPIDERMAL growth factor receptors , *LYSOSOMES , *ZINC-finger proteins , *UBIQUITINATION - Abstract
Activation of the epidermal growth factor receptor (EGFR) results in internalization and ubiquitin-dependent endosomal sorting, leading to lysosomal degradation. Here we describe the role of the RING-finger-domain-containing protein RNF126 and the related protein, Rabring7 in EGFR endosomal sorting. We demonstrate that RNF126 specifies K48-linked chains with UbcH5b and also functions with Ubc13/Uev1a to form K63-linked chains in vitro. RNF126 and Rabring7 associate with the EGFR through a ubiquitin-binding zinc finger domain and both E3 ubiquitin ligases promote ubiquitylation of EGFR. In the absence of c-Cbl or in cells expressing Cbl-70Z, the binding of RNF126 and Rabring7 to the EGFR is reduced, suggesting that RNF126 and Rabring7 function downstream of c-Cbl. In HeLa cells depleted of either RNF126 or Rabring7 the EGFR is retained in a late endocytic compartment and is inefficiently degraded. In addition, depletion of RNF126 or Rabring7 destabilizes ESCRT-II and reduces the number of multivesicular bodies formed after EGF stimulation. We also show that the depletion of Rabring7 attenuates the degradation of MET and that both RNF126 and Rabring7 regulate the sorting of CXCR4 from an early endocytic compartment. Together these data suggest that RNF126 and Rabring7 play a role in the ubiquitin-dependent sorting and downregulation of membrane receptors. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
40. THE HYDRODYNAMIC RADIUS OF PARTICLES IN THE HYBRID LATTICE BOLTZMANN--MOLECULAR DYNAMICS METHOD.
- Author
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OLLILA, SANTTU T. T., SMITH, CHRISTOPHER J., ALA-NISSILA, TAPIO, and DENNISTON, COLIN
- Subjects
- *
MATHEMATICAL models of hydrodynamics , *LATTICE Boltzmann methods , *MOLECULAR dynamics , *MULTISCALE modeling , *FRICTION , *NUMERICAL analysis - Abstract
We address the problem of the consistency of different measures of the hydrodynamic radius of solid point and composite solute particles incorporated into the hybrid lattice Boltzmann-- molecular dynamics (LBMD) multiscale method. The coupling between the fluid and the particle phase is naturally implemented through a Stokesian type of frictional force proportional to the local velocity difference between the two. Using deterministic flow tests such as measuring the Stokes drag, hydrodynamic torques, and forces we first demonstrate that in this case the hydrodynamic size of the particles is ill-defined in the existing LBMD schemes. We then show how it is possible to effectively achieve the no-slip limit in a discrete simulation with a finite coefficient of the frictional force by demanding consistency of all these measures, but this requires a somewhat modified LB algorithm for numerical stability. Having fulfilled the criteria, we further show that in our consistent coupling scheme particles also obey the macroscopically observed fluctuation-dissipation theorem for the diffusion coefficient of a single particle without any adjustable parameters. In addition, we explicitly show that diffusion alone is not a good criterion for calibration of the frictional coupling. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
41. Holding the lotus to the rock: Creating dance community in Red-State America.
- Author
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Smith, Christopher J.
- Subjects
- *
MUSIC & dance , *COMMUNITY music , *MUSICAL performance , *PRESSURE groups - Abstract
In describing the dedication necessary to transplant Buddhism to North America, the Japanese Zen master Sokei-an Sasaki (1882-1945) famously said 'it will be like holding a lotus to a rock, expecting it to take root'. Since 2001, the Texas Tech University Vernacular Music Center (VMC) (whose mission statement includes 'teaching, research, and advocacy in the world's vernacular traditions') has grown a community of collegiate dancers and musicians in the American Southwest, one that cuts across boundaries of class, age and ethnicity. Paradoxically, in this socially and culturally conservative part of the world, while receptivity to music and dance is very high - Texas is the only state in the Union that still maintains required music and art in the public schools - awareness of the art forms' available stylistic and cultural diversity is very low. Here, vernacular music communities are separated, insulated and cut-off from one another: alienated both geographically, stylistically and sociologically. At the same time, university music programmes, while recognizing the benefits to all of inclusive and diverse excellence, struggle to actualize this recognition: lacking resources, personnel, materials and/or community engagement. Drawing on musicology, ethnography, arts advocacy and mass communications theory, this article investigates the history, goals, means and methods by which the VMC has developed a series of student-centered, boundary-crossing participatory arts communities in the American Southwest, and provides both a practical toolbox, a political vocabulary and a philosophical framework for building like bridges elsewhere [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
42. Some Nonlinear Vortex Solutions.
- Author
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Haslam, Michael C., Smith, Christopher J., Alobaidi, Ghada, and Mallier, Roland
- Subjects
- *
NONLINEAR theories , *STEADY-state flow , *INVISCID flow , *MATHEMATICAL forms , *POISSON'S equation , *MATHEMATICAL analysis - Abstract
We consider the steady-state two-dimensional motion of an inviscid incompressible fluid which obeys a nonlinear Poisson equation. By seeking solutions of a specific form, we arrive at some interesting new nonlinear vortex solutions. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
43. Blacks and Irish on the Riverine Frontiers.
- Author
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Smith, Christopher J.
- Subjects
- *
IMMIGRANTS , *IRISH people , *BLACKFACE entertainers , *VAUDEVILLE , *RIVER boats - Abstract
In this article the author discusses Irish immigrants to the southern United States and the impact their interaction with the black population had on the development of American popular music. The author states his opinion that Irish performers in blackface actually admired black music but disguised their performance as racist to avoid being accused of attraction to a pariah culture. A number of other topics are addressed including the transmission of black music to Irish immigrants audiences in the northern U.S., music on riverboats, and the creation of vaudeville music.
- Published
- 2011
- Full Text
- View/download PDF
44. The IPCC Sixth Assessment Report WGIII climate assessment of mitigation pathways: from emissions to global temperatures.
- Author
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Kikstra, Jarmo S., Nicholls, Zebedee R. J., Smith, Christopher J., Lewis, Jared, Lamboll, Robin D., Byers, Edward, Sandstad, Marit, Meinshausen, Malte, Gidden, Matthew J., Rogelj, Joeri, Kriegler, Elmar, Peters, Glen P., Fuglestvedt, Jan S., Skeie, Ragnhild B., Samset, Bjørn H., Wienpahl, Laura, van Vuuren, Detlef P., van der Wijst, Kaj-Ivar, Khourdajie, Alaa Al, and Forster, Piers M.
- Subjects
- *
CLIMATE change mitigation , *DOWNSCALING (Climatology) , *SCIENCE journalism , *RADIATIVE forcing , *PHYSICAL sciences - Abstract
While the IPCC's physical science report usually assesses a handful of future scenarios, the IPCC Sixth Assessment Working Group III report (AR6 WGIII) on climate mitigation assesses hundreds to thousands of future emissions scenarios. A key task is to assess the global-mean temperature outcomes of these scenarios in a consistent manner, given the challenge that the emission scenarios from different integrated assessment models come with different sectoral and gas-to-gas coverage and cannot all be assessed consistently by complex Earth System Models. In this work, we describe the "climate assessment" workflow and its methods, including infilling of missing emissions and emissions harmonisation as applied to 1,202 mitigation scenarios in AR6 WGIII. We evaluate the global-mean temperature projections and effective radiative forcing characteristics (ERF) of climate emulators FaIRv1.6.2, MAGICCv7.5.3, and CICERO-SCM, discuss overshoot severity of the mitigation pathways using overshoot degree years, and look at an interpretation of compatibility with the Paris Agreement. We find that the lowest class of emission scenarios that limit global warming to "1.5°C (with a probability of greater than 50%) with no or limited overshoot" includes 90 scenarios for MAGICCv7.5.3, and 196 for FaIRv1.6.2. For the MAGICCv7.5.3 results, "limited overshoot" typically implies exceedance of median temperature projections of up to about 0.1°C for up to a few decades, before returning to below 1.5°C by or before the year 2100. For more than half of the scenarios of this category that comply with three criteria for being "Paris-compatible", including net-zero or net-negative greenhouse gas (GHG) emissions, are projected to see median temperatures decline by about 0.3-0.4°C after peaking at 1.5-1.6°C in 2035-2055. We compare the methods applied in AR6 with the methods used for SR1.5 and discuss the implications. This article also introduces a 'climate-assessment' Python package which allows for fully reproducing the IPCC AR6 WGIII temperature assessment. This work can be the start of a community tool for assessing the temperature outcomes related to emissions pathways, and potential further work extending the workflow from emissions to global climate by downscaling climate characteristics to a regional level and calculating impacts. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
45. China's Response to Pandemics: From Inaction to Overreaction.
- Author
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Yanzhong Huang and Smith, Christopher J.
- Subjects
- *
POLITICAL ecology , *GOVERNMENT policy , *MEDICAL policy -- Social aspects , *HIV , *SARS disease , *INFLUENZA A virus, H1N1 subtype - Abstract
The article focuses on the effects China's government policies on geography and political ecology of pandemic disease outbreaks such as HIV/AIDS, SARS, and H1N1 on the past two decades. It relates the concerns that emerged with the policies which highlight the unexpected side-effects in location, incidence, and pandemics as well as its impact on the progression of disease outbreaks. The suggestion that state policies prompted the severity of pandemic diseases in the country is also stated.
- Published
- 2010
- Full Text
- View/download PDF
46. Novel Inhibitors Complexed with Glutamate Dehydrogenase.
- Author
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Ming Li, Smith, Christopher J., Walker, Matthew T., and Smith, Thomas J.
- Subjects
- *
GLUTAMATE dehydrogenase , *INSULIN shock , *POLYPHENOLS , *GREEN tea , *COENZYMES , *LIGANDS (Biochemistry) - Abstract
Mammalian glutamate dehydrogenase (GDH) is a homohexameric enzyme that catalyzes the reversible oxidative deamination of L-glutamate to 2-oxoglutarate using NAD(P)+ as coenzyme. Unlike its counterparts from other animal kingdoms, mammalian GDH is regulated by a host of ligands. The recently discovered hyperinsulinism/hyperammonemia disorder showed that the loss of allosteric inhibition of GDH by GTP causes excessive secretion of insulin. Subsequent studies demonstrated that wild-type and hyperinsulinemia/hyperammonemia forms of GDH are inhibited by the green tea polyphenols, epigallocatechin gallate and epicatechin gallate. This was followed by high throughput studies that identified more stable inhibitors, including hexachlorophene, GW5074, and bithionol. Shown here are the structures of GDH complexed with these three compounds. Hexachlorophene forms a ring around the internal cavity in GDH through aromatic stacking interactions between the drug and GDH as well as between the drug molecules themselves. In contrast, GW5074 and bithionol both bind as pairs of stacked compounds at hexameric 2-fold axes between the dimers of subunits. The internal core of GDH contracts when the catalytic cleft closes during enzymatic turnover. None of the drugs cause conformational changes in the contact residues, but all bind to key interfaces involved in this contraction process. Therefore, it seems likely that the drugs inhibit enzymatic turnover by inhibiting this transition. Indeed, this expansion/contraction process may play a major role in the inter-subunit communication and allosteric regulation observed in GDH. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
47. Familial associations of intense preoccupations, an empirical factor of the restricted, repetitive behaviors and interests domain of autism.
- Author
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Smith, Christopher J., Lang, Colleen M., Kryzak, Lauren, Reichenberg, Abraham, Hollander, Eric, and Silverman, Jeremy M.
- Subjects
- *
CHILD development , *AUTISM , *PERSONALITY disorders , *DEVELOPMENTAL disabilities , *GENETICS , *HEREDITY - Abstract
Background: Clinical heterogeneity of autism likely hinders efforts to find genes associated with this complex psychiatric disorder. Some studies have produced promising results by restricting the sample according to the expression of specific familial factors or components of autism. Previous factor analyses of the restricted, repetitive behaviors and interest (RRBI) domain of autism have consistently identified a two-factor model that explains a moderate amount of variance. The identification of additional factors may explain more variance in the RRBI domain and provide an additional component of autism that may help in the identification of underlying genetic association. Methods: We conducted factor analyses of RRBI symptoms with a sample that included verbal subjects meeting full criteria for autism aged 5 to 22 years ( n = 245). Among affected sibling pairs ( n = 126) we examined the familial aggregation of the identified factors. We also examined the associations of the factors with autism-related personality traits in fathers and mothers ( n = 50). Results: The previously identified two-factor model – insistence on sameness (IS) and repetitive stereotypic motor behaviors (RSMB) – was replicated in our sample. Next, a second factor analysis that included the item for verbal rituals resulted in a four-factor model – IS, ‘simple’ RSMB, ‘complex’ RSMB, and a fourth factor including symptoms associated with intense preoccupations (IP). Of these four, both IS and IP were significantly familial among affected siblings, but only IP was significantly correlated with the broader autism phenotype traits of rigidity and aloofness in fathers. Conclusions: The results support previous evidence for the IS factor, its familiality, and the identification of IP as an additional strong candidate trait for genetic studies of autism. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
48. Tolerability of atypical antipsychotics in the treatment of adults with schizophrenia or bipolar disorder: A mixed treatment comparison of randomized controlled trials
- Author
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Edwards, Steven J. and Smith, Christopher J.
- Subjects
- *
DRUG tolerance , *ANTIPSYCHOTIC agents , *SCHIZOPHRENIA treatment , *BIPOLAR disorder , *THERAPEUTICS , *RANDOMIZED controlled trials , *ADULTS , *HEALTH outcome assessment , *MEDICAL statistics - Abstract
Abstract: Objective: This article reviews and compares the tolerability profiles of atypical antipsychotics in adults with schizophrenia or bipolar disorder in randomized controlled trials (RCTs). Methods: A systematic search of the BIOSIS, Cochrane Central Register of Controlled Trials, EMBASE, MEDLINE, and PsycINFO databases was conducted for English-language papers and abstracts that reported RCTs comparing ≥2 atypical antipsychotics (aripiprazole, olanzapine, quetiapine, risperidone, ziprasidone) in the treatment of adult patients with schizophrenia or bipolar disorder. The search was completed in December 2007. A panel of 4 psychiatrists with expertise in the treatment of schizophrenia, schizoaffective disorder, or bipolar disorder identified potentially relevant outcomes that would reflect patients'' subjective perception of adverse effects during treatment with antipsychotic medications. These outcomes were daily activities, anxiety or depression, bodily anxiety or restlessness, dizziness or nausea, extrapyramidal symptoms (EPS), sexual dysfunction, stiffness or tremor, tiredness or weakness, and weight gain. Data on these outcomes were extracted from relevant studies, and mixed treatment comparisons were conducted using Bayesian Markov Chain Monte Carlo simulation. Summary effect estimates (odds ratios [ORs] and 95% credible intervals [95% CrIs]) were calculated and reported in comparison with risperidone. Results: The search identified 2963 potentially relevant publications, of which 50 provided data on 48 RCTs comparing ≥2 atypical antipsychotics. Outcomes that were statistically significant compared with risperi-done at the 5% level were decreased bodily anxiety or restlessness with quetiapine (OR = 0.506; 95% CrI = 0.290, 0.789), decreased EPS with quetiapine (OR = 0.441; 95% CrI = 0.129, 0.910), increased weight gain with olanzapine (OR = 2.139; 95% CrI = 1.764, 2.626), and decreased weight gain with ziprasidone (OR = 0.466; 95% CrI = 0.317, 0.657). Conclusion: The atypical antipsychotics had mixed tolerability profiles in this mixed treatment comparison, with some agents having significantly greater tolerability than others depending on the outcome assessed. [Copyright &y& Elsevier]
- Published
- 2009
- Full Text
- View/download PDF
49. Monumentality in Urban Design: The Case of China.
- Author
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Smith, Christopher J.
- Subjects
- *
URBAN life , *URBAN planning , *LAND use planning , *URBAN renewal , *LAND use , *BUILDINGS , *CONSTRUCTION industry , *PUBLIC works - Abstract
The article offers information on the monumental urban design in China. It outlines the major landmarks and land use projects in several cities in China, including Beijing, Shanghai, and Guangzhou. Details related to the effect of Chinese State's regulation in everyday urban life are presented. The monumental works in preparation for the Beijing Olympics are presented, followed by discussion on how the event are continuously shaping the Chinese urban cities. It is mentioned that the current clearing of city neighborhoods, as well as mass displacement of residents to give way for megaproject-related constructions, have prompted opposition and resistance at the local levels.
- Published
- 2008
- Full Text
- View/download PDF
50. Efficacy of routine follow-up in patients with recurrent uterine cancer
- Author
-
Smith, Christopher J., Heeren, Monique, Nicklin, James L., Perrin, Lewis C., Land, Russell, Crandon, Alex J., and Obermair, Andreas
- Subjects
- *
CANCER patients , *ONCOLOGY , *TUMORS , *CYTOLOGY - Abstract
Abstract: Objective. : To evaluate the efficacy of routine follow-up in patients with recurrent uterine cancer. Methods. : In a single institution study, a total of 2637 patients were treated curatively for uterine cancer from 1990 to 2006. A total of 438 patients experienced disease recurrence. Data for detailed analysis were available from 280 of the 438 patients. Prior to the diagnosis of recurrence, all patients had regular follow-up and were investigated through internal examination, vaginal vault cytology and imaging. Overall survival (OS) was the main study endpoint and was calculated from recurrence diagnosis to death or date censored. Results. : Clinical and histopathological features as well as patterns of recurrence were similar in symptomatic and asymptomatic patients. Eighty-one patients (28.9%) were diagnosed with asymptomatic recurrence while 199 patients (71.1%) presented with symptomatic recurrence. The overall survival probability at 5 years was 41.0% and 28.9% respectively for asymptomatic and symptomatic patients (log-rank p =0.013). Those patients with stage 1 or 2 tumors of endometrioid type were found to have an overall survival probability at 5 years of 38.0% and 25.7% respectively for asymptomatic and symptomatic recurrence (log-rank p =0.05). The absence of symptoms did not impact on the outcome of patients with stage 3 tumors or tumors of non-endometrioid type. Conclusions. : While patients at low/intermediate risk of recurrence may benefit from intensive follow-up including internal examinations, routine vaginal vault cytology and imaging, high-risk patients might gain more from an alternate follow-up strategy with emphasis on imaging in conjunction with symptom education. [Copyright &y& Elsevier]
- Published
- 2007
- Full Text
- View/download PDF
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