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A data-driven method is presented for improving sampling designs from times series (1D approach) or spatial arrays (2D approach) of digital information. We present the autocorrelated conditioned Latin Hypercube Sampling (acLHS). This method combines a conditioned Latin Hypercube (cLHS) to obtain a representative sample of the joint probability distribution function and an autocorrelation model to reproduce the spatial or temporal dependency function (i.e., temporal or spatial variability). The acLHS method was tested with two case studies using data of soil CO 2 efflux (i.e., the CO 2 flux from soils to the atmosphere known as soil respiration) that are useful for carbon cycle science. First, we used data representing a time series (1D approach), and then spatial data (2D approach) across the conterminous United States (CONUS). Results show that acLHS was more efficient than other sampling methods (i.e., fixed sampling, cLHS) as it better reproduced the joint probability distribution and the temporal or spatial variability of the variable of interest. Finally, we use a Bernstein copula-based stochastic co-simulation method (BCSCS) and demonstrated that the acLHS reduces modeling prediction errors compared with other methods. The acLHS is a flexible method that can be applied to any variable of interest as a time series (1D approach) or as a spatial format (2D approach). • A geostatistical sampling method to improve representativeness of samples. • Implementation works for time series (1D) and spatial information (2D). • The method improves accuracy and precision for prediction purposes. [ABSTRACT FROM AUTHOR]

Tree stems exchange carbon dioxide, methane, and nitrous oxide with the atmosphere. The biophysical mechanisms controlling these fluxes are not fully understood, and consequently are not included in process-based models. We highlight advances and opportunities that will allow quantification of the role of these plant structures in the local-to-global balance of greenhouse gases (GHGs). [ABSTRACT FROM AUTHOR]

Purpose: To present a retrospective study of 13 children with benign epilepsy with centrotemporal spikes (BECTS), also known as benign rolandic epilepsy (BRE), associated with generalized spikes and waves as the only EEG manifestation at onset.Method: Charts of children with typical clinical criteria of BRE electroclinically followed-up between February 2000 and February 2015 were reviewed.Results: Among 309 patients who met the electroclinical criteria of BRE, we identified 13 children who presented with the typical clinical manifestations but who, on the EEG, only had generalized paroxysms at onset that continued along the course of the syndrome. Generalized spike-and-wave discharges were observed in all patients when awake and during sleep (100%). During the evolution no particular electroclinical pattern was observed. The patients responded well to antiepileptic drugs, such as valproic acid and levetiracetam. Outcome was good in all patients.Conclusions: We found evidence that patients with BRE may have generalized EEG discharges at onset as the sole manifestation lasting throughout the course of the syndrome. In some, focal paroxysms developed later. The course was benign. In our group of patients, clinical features and evolution were similar to those of typical cases of BRE. Response to valproic acid and levetiracetam was found to be particularly good. [ABSTRACT FROM AUTHOR]

Incorporation of silica-rich rice husk residue into flooded paddy soil decreases arsenic uptake by rice. However, the impact of this practice on soil greenhouse gas (GHG) emissions and elemental cycling is unresolved particularly as amended soils experience recurrent flooding and drying cycles. We evaluated the impact of pre-incubated silica-rich rice residue incorporation to soils on pore water chemistry and soil GHG fluxes (i.e., CO 2 , CH 4 , N 2 O) over a flooding and drying cycle typical of flooded rice cultivation. Soils pre-incubated with rice husk had 4-fold higher pore water Si than control and 2-fold higher than soils pre-incubated with rice straw, whereas the pore water As and Fe concentrations in soils amended with pre-incubated straw and husk were unexpectedly similar (maximum ~ 0.85 μM and ~ 450 μM levels, respectively). Pre-incubation of residues did not affect Si but did affect the pore water levels of As and Fe compared to previous studies using fresh residues where straw amended soils had higher As and Fe in pore water. The global warming potential (GWP) of soil GHG emissions decreased in the order straw (612 ± 76 g CO 2 -eq m − 2 ) > husk (367 ± 42 g CO 2 -eq m − 2 ) > ashed husk = ashed straw (251 ± 26 and 278 ± 28 g CO 2 -eq m − 2 ) > control (186 ± 23 g CO 2 -eq m − 2 ). The GWP increase due to pre-incubated straw amendment was due to: a) larger N 2 O fluxes during re-flooding; b) smaller contributions from larger CH 4 fluxes during flooded periods; and c) higher CH 4 and CO 2 fluxes at the onset of drainage. In contrast, the GWP of the husk amendment was dominated by CO 2 and CH 4 emissions during flooded and drainage periods, while ashed amendments increased CO 2 emissions particularly during drainage. This experiment shows that ashed residues and husk addition minimizes GWP of flooded soils and enhances pore water Si compared to straw addition even after pre-incubation. [ABSTRACT FROM AUTHOR]

Soil CO2 efflux is the primary source of CO2 emissions from terrestrial ecosystems to the atmosphere. The rates of this flux vary in time and space producing hot moments (sudden temporal high fluxes) and hot spots (spatially defined high fluxes), but these high reaction rates are rarely studied in conjunction with each other. We studied temporal and spatial variation of soil CO2 efflux in a water-limited Mediterranean ecosystem in Baja California, Mexico. Soil CO2 efflux increased 522% during a hot moment after rewetting of soils following dry summer months. Monthly precipitation was the primary driver of the seasonal trend of soil CO2 efflux (including the hot moment) and through changes in soil volumetric water content (VWC) it influenced the relationship between CO2 efflux and soil temperature. Geostatistical analyses showed that the spatial dependence of soil CO2 efflux changed between two contrasting seasons (dry and wet). During the dry season high soil VWC was associated with high soil CO2 efflux, and during the wet season the emergence of a hot spot of soil CO2 efflux was associated with higher root biomass and leaf area index. These results suggest that sampling designs should accommodate for changes in spatial dependence of measured variables. The spatio-temporal relationships identified in this study are arguably different from temperate ecosystems where the majority of soil CO2 efflux research has been done. This study provides evidence of the complexity of the mechanisms controlling the spatio-temporal variability of soil CO2 efflux in water-limited ecosystems. [ABSTRACT FROM AUTHOR]

Abstract: Solutions to current global environmental problems throughout fundamental ecological understandings are only reached through international programmatic and scientific collaborations. Both scientists and policymakers recognize the importance of the role of carbon cycle science (CCS) in North America, however regional ecological studies in North America often do not include the role of Mexico. Given the sharp ecological, climatic and socioeconomic differences among the three countries conforming North America it is fundamental to incorporate Mexico''s unique contributions toward regional CCS. We provide a synthesis of opportunities and challenges for advancing land and ocean research in Mexico in order to move toward a complete North American continental scale CCS. First, we provide the socio-ecological context of Mexico relevant to CCS. Second, we compare the existing relationships among scientific/governmental entities and funding agencies that contribute to CCS in the United States and Mexico. Third, we discuss Mexico''s state-of-the-art CCS, and synthesize its recent advances with emphasis on land– and ocean–atmosphere interactions. We highlight continental-scale opportunities toward a tri-national carbon research, infrastructure, and education network. [Copyright &y& Elsevier]

Tidal salt marsh ecosystems store copious amounts of carbon (C) within sediments. In order to predict how these C stores may be affected by environmental change, it is critical to assess current CO 2 and CH 4 production and efflux from these ecosystems. Production and efflux of these greenhouse gases (GHGs) are governed by coupled geochemical, hydrological, physical and biological processes in sediments that are sensitive to local conditions, which can result in large spatial and temporal heterogeneity of GHGs dynamics within the ecosystem. To understand how the drivers of GHGs dynamics vary across salt marsh ecosystems, we coupled solid-phase geochemistry to measurements of porewater chemistry (to ∼1 m), CO 2 and CH 4 production in sediments and efflux to the atmosphere in a temperate tidal salt marsh for over one year to capture seasonal patterns within two vegetation zones of the marsh landscape that have distinct biogeochemical and hydrologic conditions: Tall Spartina (TS) and Short Spartina (SS). The SS vegetation zone experienced nearly constant inundation, low redox values (−200 to 200 mV), porewater pH 6–7 that did not vary with depth or time, an enrichment of pyrite and goethite with depth and up to 3 mM porewater sulfide. In contrast, the TS vegetation zone on the natural levee proximal to a tidal channel experienced large water level oscillations due to spring-neap tides that resulted in variable but higher redox values (0–700 mV), porewater pH 6–7 at depth but surface (0–3 cm) as low as 4 in the spring, an enrichment of ferrihydrite and a depletion of pyrite at ∼30 cm, and up to 0.8 mM ferrous Fe in porewater. At 50–56 cm, solid phase analyses (STXM-NEXAFS) revealed differential C speciation between the two vegetation zones, with stronger C-Fe spatial association at TS and stronger C-Ca co-association at SS despite both having similar soil pH of 3–4. These results suggest that soil pH may not be strongly predictive of C-mineral control in flooded marsh sediments. Both vegetation zones showed consistent CO 2 and CH 4 emissions from sediments to the atmosphere throughout the study period with TS having ∼60% higher median CO 2 and SS having ∼55% higher median CH 4 efflux. Using depth profiling, unexpectedly high concentrations of CO 2 (>200 μM) and CH 4 (>200 μM) were observed at depths 50–75 cm at both zones that were higher for SS in these sulfate-rich (up to 17 mM) sediments, which suggests methylotrophic methanogenesis occurs deep within the profile of salt marsh sediments away from the tidal channel. Moreover, if we extrapolate our median depth values of CH 4 and CO 2 to the 5.3 Mha of global salt marshes, this could account for a conservative estimate of ∼70 Gg of unaccounted C stored in gaseous form (i.e., CH 4 and CO 2) in marsh sediments, which should be considered when attempting to understand the current patterns and future responses of carbon dynamics from these ecosystems. [ABSTRACT FROM AUTHOR]

Highlights: [•] Wavelet transform was applied to examine spectral characteristics of ET. [•] ET power spectra display a −1 power law at less than an hour time-scale. [•] The cospectra of ET and soil moisture show temporal correlation at 5-days. [•] ET synchronizes with net radiation, and leads vapor pressure deficit for ∼2.0h. [•] The phase relationship between ET and soil moisture is influenced by irrigation. [ABSTRACT FROM AUTHOR]

Water is a crucial factor controlling the fate and processing of soil organics. Water commonly flows through the vadose zone via preferential flow pathways, resulting in nonuniform and rapid infiltration. Hence, a large portion of the soil matrix is bypassed. Preferential flow paths, often associated with well-connected macropore networks (>300 μm Ø), offer a unique balance between water availability, nutrient delivery, and re-oxygenation upon drainage. The heightened concentrations of moisture, nutrients, and oxygen make these locations optimal for high rates of microbial activity. Flow paths often display temporal stability. This stability results in repeated wetting and biogeochemical reactivation through time creating a lasting impact on micro-environmental conditions relevant to microbial functioning and carbon cycling in soil. Despite decades of research on preferential flow, there is still a need to link flow paths and the resultant heterogeneous moisture distributions to soil function. In this review, we discuss how preferential flow can serve as a framework of reference for the spatially and temporally heterogeneous biogeochemical cycling of soil carbon. We highlight the importance of combining current knowledge of pore-scale carbon dynamics with an appreciation of connected networks of hydraulically active pores/paths within the soil profile. Such combination opens new possibilities for upscaling pore-scale processes with the inclusion of resource heterogeneity at the macroscale. Working within this hydraulically connected framework can provide insight for the mechanistic representation of hot moments, which are temporally isolated large pulses of CO 2 after rewetting or thawing events. We conclude with suggestions on knowledge gaps and stress the critical need of linking soil physics with biology to mechanistically understand soil functions. • Preferential flow paths play a key role in soil carbon dynamics. • Pore-scale carbon dynamics could be upscaled using hydraulic connectivity. • A conceptual model is presented that considers how soil pores function from hydrological and microbial perspective. [ABSTRACT FROM AUTHOR]

Abstract: The bioavailability of β-carotene from cassava (Manihot esculenta Crantz) leaves was assayed in vitamin A deficient Wistar rats (Rattus norvegicus). Rats were separated into three groups and fed with a modified AIN-93G – vitamin A deficient – diet. Deficient rat received this diet without any additional vitamin A source. Controls received the diet with 7200 μg of synthetic β-carotene (control), while experimentals (test) received 19.5 g of cassava leaves powder per kg of diet. The cassava leaves with β-carotene promotes similar growth and tissue weight in rats to the synthetic β-carotene. The relative bioavailability, estimated as the Retinol Accumulation Factor (RAF), was 16.5 and 27.5 for control and test groups, respectively, indicating that control and test rats should have an intake of 16.5 μg or 27.5 μg of β-carotene from synthetic form or cassava leaves powder for each 1 μg of hepatic retinol stored, respectively. The cassava leaves β-carotene bioavailability was lower than the synthetic β-carotene probably because the β-carotene from the leaf matrix may be bounded to protein complex or inside organelles, which impair carotenoid absorption. Our findings showed that beside the hepatic retinol recovery, cassava leaf β-carotene could maintain rat growth and avoid vitamin A deficient symptoms. [Copyright &y& Elsevier]

Storm surges can substantially alter the water level and salinity in tidal salt marshes. Little is known about how changes experienced during storm surges affect greenhouse gas emissions (GHG; CO 2 , CH 4 , N 2 O) from tidal salt marsh soils. Understanding how storm surges influence ecosystem processes is critical for evaluating the ecosystem's sensitivity to sea level rise. To explore how hurricane-induced changes in salinity affect GHG emissions, we exposed intact soil mesocosms (0–9 cm depth) from a Mid-Atlantic temperate salt marsh to pulse changes in salinity experienced at the site before, during, and after Hurricane Joaquin in 2015. Soil temperature, oxygen, and water level were kept constant to avoid confounding effects throughout the experiment. Automated measurements (hourly resolution) of soil GHG emissions were recorded in control (i.e., no salinity changes) and treatment mesocosms, and combined with soil pore water chemistry (i.e., SO 4 2−, S2−, Fe2+, TN b , redox potential, pH) to characterize the biogeochemical responses. Using mixed effects models, we found that the role of different biogeochemical processes, such as sulfur cycling, changed throughout the experiment, underscoring the complex nature of GHG emissions in tidal salt marsh soils. Overall, soils subjected to a salinity decrease had greater GHG emissions than control soils, which were maintained at 17 ppt. The treatment soils had a 24% and 23% increase in global warming potential (20- and 100-year scenarios, respectively) indicating that storm surges can produce pulses of GHG emissions. However, both CH 4 and N 2 O emissions returned to baseline values (following hysteresis responses) when initial conditions were reestablished. The results support the fact that tidal salt marshes are resilient ecosystems, as soil GHG emissions recovered relatively quickly from the pulse event. Unlabelled Image • Studied the influence a pulse-change in salinity on salt marsh GHG biogeochemistry • Coupled automated GHG measurements with pore water chemistry • CO 2 decreased with decreased salinity; CH 4 , and N 2 O fluxes increased. • Salt marsh soils recovered from salinity changes relatively quickly. [ABSTRACT FROM AUTHOR]

An emerging approach to limit rice uptake and grain As targets the shared root-uptake pathway between As(III) and Si. We amended rice paddy mesocosms with Si-rich rice residues (husk and husk char) or silicate fertilizer to evaluate the impact of different Si sources on rice uptake of Si and As including As speciation in grain under background soil As. For a systems-approach, we also measured plant biomass, rice yield, porewater chemistry, mesocosm-scale CH 4 and CO 2 fluxes, plant concentrations of nutrients and metals, and root Fe plaque mineralogy. Relative to the control, Si-rich amendments increased plant Si and proportion of ferrihydrite on root plaque, decreased root-to-shoot Mn transfer and As uptake, and shifted grain As from inorganic to organic As. The charred husk treatment, which resulted in the most Si accumulation in rice shoots, most decreased plant As and grain As. Husk treatment led to the highest CH 4 emissions, but all treatments had lower CH 4 emissions than has been reported for straw treatments. Collectively, Si-rich amendments performed similarly across several biogeochemical benchmarks, with charred husk best restricting plant As, suggesting these amendments can be used to reduce toxicity of As from rice grain while maintaining yield. [ABSTRACT FROM AUTHOR]

Marine carbonate system monitoring programs often consist of multiple observational methods that include underway cruise data, moored autonomous time series, and discrete water bottle samples. Monitored parameters include all, or some of the following: partial pressure of CO 2 of the water ( p CO 2w ) and air, dissolved inorganic carbon (DIC), total alkalinity (TA), and pH. Any combination of at least two of the aforementioned parameters can be used to calculate the others. In this study at the Gray's Reef (GR) mooring in the South Atlantic Bight (SAB) we: examine the internal consistency of p CO 2w from underway cruise, moored autonomous time series, and calculated from bottle samples (DIC-TA pairing); describe the seasonal to interannual p CO 2w time series variability and air-sea flux ( F CO 2 ), as well as describe the potential sources of p CO 2w variability; and determine the source/sink for atmospheric p CO 2 . Over the ~8.5 years of GR mooring time series, mooring-underway and mooring-bottle calculated- p CO 2w strongly correlate with r -values > 0.90. p CO 2w and F CO 2 time series follow seasonal thermal patterns; however, seasonal non-thermal processes, such as terrestrial export, net biological production, and air-sea exchange also influence variability. The linear slope of time series p CO 2w increases by 5.2 ± 1.4 µatm y −1 with F CO 2 increasing 51–70 mmol m −2 y −1 . The net F CO 2 sign can switch interannually with the magnitude varying greatly. Non-thermal p CO 2w is also increasing over the time series, likely indicating that terrestrial export and net biological processes drive the long term p CO 2w increase. [ABSTRACT FROM AUTHOR]

Quantifying and identifying measurement error is an ongoing challenge for carbon cycle science to constrain measurable uncertainty related to the sources and sinks of CO 2 . One source of uncertainty in measurements is derived from random errors ( ε ); thus, it is important to quantify their magnitude and their relationship to environmental variability in order to constrain local-to-global carbon budgets. We applied a paired-observation method to determine ε associated with marine x CO 2 in a coastal upwelling zone of an eastern boundary current. Continuous data (3-h resolution) from a mooring platform during upwelling and non-upwelling seasons was analyzed off of northern Baja California in the California Current. To test the rigor of the algorithm to calculate ε we propose a method for determining daily mean time series values that may be affected by ε . To do this we used either two or three variables in the function, but no significant differences for ε mean values were found due to the large variability in ε (−0.088 ± 27 ppm for two variables and −0.057 ± 28 ppm for three variables). Mean ε values were centered on zero, with low values of ε more frequent than greater values, and follow a double exponential distribution. Random error variability increased with higher magnitudes of x CO 2 , and in general, ε variability increased in relation to upwelling conditions (up to ∼9% of measurements). Increased ε during upwelling suggests the importance of meso-scale processes on ε variability and could have a large influence seasonal to annual CO 2 estimates. This approach could be extended and modified to other marine carbonate system variables as part of data quality assurance/quality control and to quantify uncertainty (due to ε ) from a wide variety of continuous oceanographic monitoring platforms. [ABSTRACT FROM AUTHOR]

Energy costs account for an important share of the total costs of urban and suburban bus operators. The purpose of this paper is to expand empirical research on bus transit operation costs and identify the key factors that influence bus energy efficiency of the overall bus fleet of one operator and aid to the management of its resources. We estimate a set of multivariate regression models, using cross-section dataset of 488 bus drivers operating over 92 days in 2010, in 87 routes with different bus typologies, of a transit company operating in the Lisbon’s Metropolitan Area (LMA), Rodoviária de Lisboa, S.A. Our results confirm the existence of influential variables regarding energy efficiency and these are mainly: vehicle type, commercial speed, road grades over 5% and bus routes; and to a lesser extent driving events such as: sudden longitudinal decelerations and excessive engine rotation. The methodology proved to be useful for the bus operator as a decision-support tool for efficiency optimization purpose at the company level. [ABSTRACT FROM AUTHOR]

Abstract: Understanding the dynamics of leaf area index (LAI) at ecosystem scale is critical for evaluating and modeling the response of vegetation to environmental variability and change. We present an approach for quantifying daily ecosystem LAI that integrates automatic acquisition of a small number of reference photos, viewed towards the zenith, and a larger number of photos covering a spatially extensive area that were manually acquired during periodic field trips. We present an image archive spanning three years for an oak-savanna ecosystem in California to identify the timing of phenological and disturbance events, and to quantify the seasonal to interannual variability of tree LAI at ecosystem scale. The digital camera-derived LAI, corrected for clumping effects, agreed well (r2 =0.94, root mean square error=0.05) with independent estimates of LAI from litterfall traps and the LAI-2000 Plant Canopy Analyzer. Using the Moderate Resolution Imaging Spectroradiometer (MODIS) LAI product, which combined grass and tree LAI, we obtained realistic seasonal patterns of ecosystem LAI that corresponded with tree LAI from the digital cameras for the period when grass was dead. The digital camera method is an easy and inexpensive way to monitor LAI at ecosystem scale. This method can be used for testing and improving phenology models, evaluating remote-sensing-derived LAI products, and quantifying forest structures in rapidly changing environments. [Copyright &y& Elsevier]

Abstract: Talisin is a seed-storage protein from Talisia esculenta that presents lectin-like activities, as well as proteinase-inhibitor properties. The present study aims to provide new in vitro and in silico biochemical information about this protein, shedding some light on its mechanistic inhibitory strategies. A theoretical three-dimensional structure of Talisin bound to trypsin was constructed in order to determine the relative interaction mode. Since the structure of non-competitive inhibition has not been elucidated, Talisin-trypsin docking was carried out using Hex v5.1, since the structure of non-competitive inhibition has not been elucidated. The predicted non-coincidence of the trypsin binding site is completely different from that previously proposed for Kunitz-type inhibitors, which demonstrate a substitution of an Arg64 for the Glu64 residue. Data, therefore, provide more information regarding the mechanisms of non-competitive plant proteinase inhibitors. Bioassays with Talisin also presented a strong insecticide effect on the larval development of Diatraea saccharalis, demonstrating LD50 and ED50 of ca. 2.0% and 1.5%, respectively. [Copyright &y& Elsevier]

We present velocities relative to the South American plate for five GPS stations on the Nazca plate and use these measurements to estimate the modern Euler vector. We find a pole at 55.8°N, 92.5°W with a rotation rate of 0.60 °/Myr. Because the GPS station at Easter Island appears to be moving at approximately 6.6 mm/yr relative to the other Nazca stations, we repeat our analysis with this station excluded from the inversion to obtain a second and preferred result (called CAP10) with a pole at 61.0°N, 94.4°W and a rate of 0.57 °/Myr. We compare these results with published finite rotation vectors and infer that during the past 10–20 Myrs, the Nazca–South America rotation rate has decelerated by 0.04°–0.06 °/Myr2. [Copyright &y& Elsevier]