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Arctic carbon dioxide emissions during the winter months are frequently omitted from global carbon budgets, due to prior assumptions that their contribution is largely insignificant compared to other sources and seasons. This paradigm has recently been challenged, amid a growing awareness of the impact snow-ecosystem interactions have on respiration from high-latitude soils and overall carbon budgets. Through field measurements at Trail Valley Creek, NWT, Canada, and simulations using the Community Land Model 5.0, here we: consider how the representation of snow thermal conductivity in a Terrestrial Biosphere Model impacts simulated near-surface soil temperatures and net ecosystem exchange,report on new low-cost in-situ measurement techniques that aim to quantify carbon dioxide concentrations and fluxes within Arctic snowpacks.We anticipate new measurement techniques will help evaluate rates of production of carbon dioxide from frozen soils during winter months and address discrepancies between observed and simulated carbon dioxide emissions. Increased confidence in future simulations is important in a region that is highly characteristic of the high latitude critical zone, susceptible to permafrost thaw, and is warming two to three times as fast as the global average since the late twentieth century., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Seasonal snow cover extent is an essential climate variable that is, in principle, easy to measure with optical remote sensing because of the high contrast in albedo between snow and snow-free ground. In practice, however, the amount of information is severely limited by cloud cover globally and seasonal darkness at high latitudes. The European Space Agency snow cci project has now generated long-term global, daily snow cover products from AVHRR (1982-2018 at 5 km resolution) and MODIS (2000-2020 at 1 km resolution). To investigate the information content of these products and the level of uncertainty in gap filling with data assimilation for Arctic tundra snow, we take advantage of newly available in situ 1991-2022 meteorological time series for Trail Valley Creek, Northwest Territories, Canada. As a contribution to the ESM-SnowMIP project, we evaluate the ability of snow cover observations with and without gap filling to discriminate between climate model simulations submitted for CMIP6., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Arctic permafrost soils are estimated to contain 1700 Gt of carbon and a warming climate signals more rapid release of CO2 from these environments, further exacerbating the warming effect of greenhouse gases. CO2 emissions from Arctic soils during the cold season were previously thought to be negligible; this is not the case and their contribution to the overall annual carbon budget is expected to increase in a warming world.Few observational and modelling studies have been directed at Arctic cold season carbon cycling processes, ultimately making any future projections of CO2 release unreliable. This unreliability is compounded by uncertainty in (1) the land component of Earth System Models regarding the parameterizations of biogeophysical and biogeochemical processes driving CO2 release during winter and (2) projections of future climate in the Arctic.Here, we use the CLM5.0 model in point mode for Trail Valley Creek near Inuvik NT, forced by ERA5 reanalysis to evaluate the performance of CLM5.0 for present-day conditions using flux tower measurements of net ecosystem CO2 exchange as model constraints. We then apply a bias-corrected NA-CORDEX ensemble of RCP4.5 and RCP8.5 scenarios to quantify the variability in future winter CO2 emissions due to (1) model uncertainty in future climate conditions and (2) parameter uncertainty in CLM5.0 relating to the temperature sensitivity of soil respiration (Q10), the moisture threshold for soil decomposition and the thermal conductivity scheme for the snow layer. The latter is a strong control on the thermal evolution of soil temperature, and therefore soil respiration during the winter., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Classically, the rotation of ellipsoids in shear Stokes flow is captured by Jeffery’s orbits. Here, we demonstrate that Jeffery’s orbits also describe high-frequency shape-deforming swimmers moving in the plane of a shear flow, employing only basic properties of Stokes flow and a multiple-scales asymptotic analysis. In doing so, we support the use of these simple models for capturing shapechanging swimmer dynamics in studies of active matter and highlight the ubiquity of ellipsoid-like dynamics in complex systems. This result is robust to weakly confounding effects, such as distant boundaries, and also applies in the low-frequency limit.

Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a rare type of non-Hodgkin T-cell lymphoma, recently defined in the 2016 World Health Organization (WHO) classification of lymphoid neoplasms. It occurs more commonly when textured implants are used and appears clinically as a late seroma. Cytologically, these lesions are composed of large atypical cells with pleomorphic nucleus and an immunophenotype positive for T cell markers and CD30, and negative for ALK1. We report a 56-years-old woman with breast implants who developed a periprosthetic seroma three years after surgery. A fine needle aspiration of the lesion was carried out. Cytology and the immunocytochemical study revealed cells compatible with BIA-ALCL. The flow cytometric study was negative. Excisional biopsy of the capsule was performed, observing that the neoplastic cells were confined to the inner surface of the capsule. Imaging studies did not find evidence of disseminated disease. The present case demonstrates the importance of the study of any late periprosthetic effusion, which can be performed using fine needle aspiration.

Introduction Historically, copperhead snake (Agkistrodon contortrix) envenomations were not treated with antivenom owing to related adverse events and little benefit. However, recent studies have shown improved outcomes with antivenom use. We hypothesized that the frequency of antivenom use for copperhead envenomation in Ohio has increased as benefits of administration became more widely known. Methods All copperhead snakebites reported to the Ohio poison control centers from 2006 through 2016 were compiled. Antivenom use, bite severity, and disposition were abstracted. A nonparametric test for trend was used to evaluate changes over time for the number of patients treated with antivenom and patient disposition. Logistic regression was used to assess the odds of admission vs discharge with antivenom administration, bite severity, age, and sex as independent variables. Results Ninety-eight patients reported copperhead snakebites to the poison control centers. The test of trend showed no change in the proportion of patients treated with antivenom by year (P=0.42). There was no difference in the proportion of patients discharged home (P=0.38) per year. Logistic regression showed antivenom use was associated with an odds ratio for admission of 46.7 (95% CI: 7.3–296.4). Conclusions The frequency of antivenom use for copperhead bites did not significantly increase between 2006 and 2016. Administration of antivenom was associated with a large increase in the odds of admission to the hospital, even when controlling for bite severity. Further education regarding the benefits and safety of antivenom may increase its use for copperhead snakebites, but may lead to an increase in hospital admissions.

Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a rare type of non-Hodgkin T-cell lymphoma, recently defined in the 2016 World Health Organization (WHO) classification of lymphoid neoplasms. It occurs more commonly when textured implants are used and appears clinically as a late seroma. Cytologically, these lesions are composed of large atypical cells with pleomorphic nucleus and an immunophenotype positive for T cell markers and CD30, and negative for ALK1. We report a 56-years-old woman with breast implants who developed a periprosthetic seroma three years after surgery. A fine needle aspiration of the lesion was carried out. Cytology and the immunocytochemical study revealed cells compatible with BIA-ALCL. The flow cytometric study was negative. Excisional biopsy of the capsule was performed, observing that the neoplastic cells were confined to the inner surface of the capsule. Imaging studies did not find evidence of disseminated disease. The present case demonstrates the importance of the study of any late periprosthetic effusion, which can be performed using fine needle aspiration.

The eye grows during childhood to position the retina at the correct distance behind the lens to enable focused vision, a process called emmetropization. Animal studies have demonstrated that this growth process is dependent upon visual stimuli, while genetic and environmental factors that affect the likelihood of developing myopia have also been identified. The coupling between growth, remodeling and elastic response in the eye is particularly challenging to understand. To analyse this coupling, we develop a simple model of an eye growing under intraocular pressure in response to visual stimuli. Distinct to existing three-dimensional finite-element models of the eye, we treat the sclera as a thin axisymmetric hyperelastic shell which undergoes local growth in response to external stimulus. This simplified analytic model provides a tractable framework in which to evaluate various emmetropization hypotheses and understand different types of growth feedback, which we exemplify by demonstrating that local growth laws are sufficient to tune the global size and shape of the eye for focused vision across a range of parameter values.

This article examines what it means to produce critical continental philosophyin contexts where the label of “continental” may seem increasingly tenuous, ifnot entirely anachronistic. We follow Ghassan Hage in understanding “criticalthought” as enabling us “to reflexively move outside of ourselves such that wecan start seeing ourselves in ways we could not have possibly seen ourselves, ourculture or our society before.” Such thought may involve an interrogation of ourown conditions of knowledge production, by giving us “access to forces that areoutside of us but that are acting on us causally.” Our argument in this article isthat critical approaches within continental philosophy need to examine a multiplicity of ways that disciplines can be defined and delimited, and to understandthe ways that gender, geography, and coloniality (among other forces) shape theintellectual and social worlds of continental philosophy. In doing so, we wantto consider the ways that familiar debates around intellectual and institutionalbiases might be enhanced by a closer consideration of process-based aspects ofdisciplinary self-reproduction, and we take as our example the Australasian Society for Continental Philosophy (ASCP) conference at the University of Tasmania(November 29-December 1, 2017). We also consider Nelson Maldonado-Torres’notion of “post-continental philosophy,” and reflect on the implications of sucha venture in the Australian context. But to begin with, we want to navigate a pathbetween two modes of criticism commonly directed toward philosophy as a discipline.

© 2018 Elsevier Inc. El Niño Southern Oscillation events (ENSO) and the subsequent opposite weather patterns in the following months and years (La Niña) have major climatic impacts, especially on oceanic habitats, affecting breeding success of both land and sea birds. We assessed corticosterone concentrations from blood samples during standardized protocols of capture, handling and restraint to simulate acute stress from 12 species of Galapagos Island birds during the ENSO year of 1998 and a La Niña year of 1999. Plasma levels of corticosterone were measured in samples collected at capture (to represent non-stressed baseline) and subsequently up to 1 h post-capture to give maximum corticosterone following acute stress, and total amount of corticosterone that the individual was exposed to during the test period (integrated corticosterone). Seabird species that feed largely offshore conformed to the brood value hypothesis whereas inshore feeding species showed less significant changes. Land birds mostly revealed no differences in the adrenocortical responses to acute stress from year to year with the exception of two small species (

Highlights • L. mexicana behaviour near a no-slip surface is studied via boundary element methods. • Model flagellar beat for Leishmania promastigotes is identified from videomicroscopy. • Idealised simulation of boundary approach shows dichotomy of deflection or collision. • Repulsive surface forces do not induce stable boundary accumulation in this puller. • Tip-first boundary approach may be promoted by morphology-dependent drag., Graphical abstract, It is well established that the parasites of the genus Leishmania exhibit complex surface interactions with the sandfly vector midgut epithelium, but no prior study has considered the details of their hydrodynamics. Here, the boundary behaviours of motile Leishmania mexicana promastigotes are explored in a computational study using the boundary element method, with a model flagellar beating pattern that has been identified from digital videomicroscopy. In particular a simple flagellar kinematics is observed and quantified using image processing and mode identification techniques, suggesting a simple mechanical driver for the Leishmania beat. Phase plane analysis and long-time simulation of a range of Leishmania swimming scenarios demonstrate an absence of stable boundary motility for an idealised model promastigote, with behaviours ranging from boundary capture to deflection into the bulk both with and without surface forces between the swimmer and the boundary. Indeed, the inclusion of a short-range repulsive surface force results in the deflection of all surface-bound promastigotes, suggesting that the documented surface detachment of infective metacyclic promastigotes may be the result of their particular morphology and simple hydrodynamics. Further, simulation elucidates a remarkable morphology-dependent hydrodynamic mechanism of boundary approach, hypothesised to be the cause of the well-established phenomenon of tip-first epithelial attachment of Leishmania promastigotes to the sandfly vector midgut.

Based on Self Determination and Achievement Goal theories, in this study we tested the relationship between perceptions of coaches’ in- terpersonal styles, athlete’s goal orientations, mental toughness (MT) and future intention of sport practice, as well as self-perception of achievement in sport in a sample of 155 athletes (82 men and 73 women) with a mean age of 22.64 + 3.91 years, from 13 teams who completed a questionnaire with the variables of interest for the study. Results revealed that athlete’s perceptions of autonomy supportive interpersonal style positively predic- ted task orientation, while athlete’s perceptions of controlling interpersonal style positively predicted ego orientation. Additionally, task orientation and self-perception of achievement in sport positively predicted MT, which in turn predicted future intention of sport practice. Results emphasize the importance of having coaches promoting autonomy supportive atmosphe- res to facilitate the development of MT in athletes. Resumen: Tomando como marco teórico las teorías motivacionales de la Autodeterminación y de las Metas de logro, en este estudio se examinaron las relaciones entre los estilos interpersonales mostrados por el entrenador, las orientaciones de meta, la dureza mental (DM) y la intención futura de práctica deportiva, así como la autopercepción de rendimiento en el depor- te en 155 deportistas (82 hombres y 73 mujeres) con una media de edad de 22.64 + 3.91 años, procedentes de 13 equipos quienes completaron un cuestionario con las variables de interés. Los resultados revelaron que la percepción de un estilo de apoyo a la autonomía predijo positivamente la orientación a la tarea, mientras que la percepción de un estilo controlador predijo positivamente la orientación al ego. La orientación a la tarea y la percepción de rendimiento en el deporte predijeron la DM, que a su vez predijo la intención futura de práctica deportiva. Los resultados enfatizan la importancia de utilizar estilos interpersonales de apoyo a la autonomía que faciliten el desarrollo de la DM en los deportistas. Resumo: Com base nas teorias de autodeterminação e metas de realização, neste estudo, testamos a relação entre as percepções dos estilos interpessoais dos treinadores, as orientações dos objetivos do atleta, a tenacidade mental (MT) e a intenção futura da prática esportiva, bem como a autopercepção da conquista no esporte em uma amostra de 155 atletas (82 homens e 73 mulheres) com idade média de 22,64 + 3,91 anos, de 13 equipes que com- pletaram um questionário com as variáveis de interesse para o estudo. Os resultados revelaram que as percepções do atleta sobre o estilo interpessoal de apoio à autonomia predisseram positivamente a orientação das tarefas, enquanto as percepções do atleta sobre o controle do estilo interpessoal pre- viam positivamente a orientação do ego. Além disso, a orientação da tarefa e a autopercepção da realização no esporte previam positivamente MT, o que, por sua vez, previu a intenção futura da prática esportiva. Os resulta- dos enfatizam a importância de ter treinadores que promovam a autonomia de ambiente de apoio para facilitar o desenvolvimento de MT em atletas.

Background. HLA strongly influences HIV-1 disease progression. A major contributory mechanism is via the particular HLA-presented HIV-1 epitopes that are recognized by CD8+ T-cells. Different populations vary considerably in the HLA alleles expressed. We investigated the HLA-specific impact of the MRKAd5 HIV-1 Gag/Pol/Nef vaccine in a subset of the infected Phambili cohort in whom the disease-susceptible HLA-B*58:02 is highly prevalent. Methods. Viral loads, CD4 counts and ELISPOT anti-HIV-1 CD8+ T-cell responses for a subset of infected ART-naïve Phambili participants, selected according to sample availability, were analyzed. Results. Among those expressing disease-susceptible HLA-B*58:02, vaccinees had a lower chronic viral setpoint than placebo-recipients (median 7,240 versus 122,500 copies/ml, p=0.01), a 0.76log10 lower longitudinal viremia (p=0.01), and slower progression to CD4andLT;350 cells/mm3 (p=0.02). These differences were accompanied by higher Gag-specific breadth (4.5 versus 1 responses, p=0.04) and magnitude (2,300 versus 70 SFC/106 PBMC, p=0.06) in vaccinees versus placebo-recipients. Conclusions. In addition to the known enhancement of HIV-1 acquisition resulting from the MRKAd5 HIV-1 vaccine, these findings in a non-randomized subset of enrolees show an HLA-specific vaccine effect on time to CD4 decline and viremia post-infection and the potential for vaccines to differentially alter disease outcome according to population HLA composition. (Registration: NCT00413725, DOH-27-0207-1539.)

Objective: To test the a priori hypothesis that longer duration of ruptured membranes is associated with increased risk of vertical transmission of HIV. Design: The relationship between duration of ruptured membranes and vertical transmission of HIV was evaluated in an individual patient data meta-analysis. Methods: Eligible studies were prospective cohort studies including at least 100 mother-child pairs, from regions where HIV-infected women are counselled not to breastfeed. Analyses were restricted to vaginal deliveries and non-elective Cesarean sections; elective Cesarean section deliveries (those performed before onset of labour and before rupture of membranes) were excluded. Results: The primary analysis included 4721 deliveries with duration of ruptured membranes ≤ 24 h. After adjusting for other factors known to be associated with vertical transmission using logistic regression analysis to assess the strength of the relationship, the risk of vertical HIV transmission increased approximately 2% with an increase of 1 h in the duration of ruptured membranes [adjusted odds ratio, 1.02; 95% confidence interval, 1.01-1.04; for each 1 h increment]. There were no significant interactions of duration of ruptured membranes with study cohort or with any of the covariates, except maternal AIDS. Among women diagnosed with AIDS, the estimated probability of transmission increased from 8% to 31% with duration of ruptured membranes of 2 h and 24 h respectively (P < 0.01). Conclusions: These results support the importance of duration of ruptured membranes as a risk factor for vertical transmission of HIV and suggest that a diagnosis of AIDS in the mother at the time of delivery may potentiate the effect of duration of ruptured membranes. © 2001 Lippincott Williams & Wilkins.

POTS (postural tachycardia syndrome) is characterized by an increased heart rate (ΔHR) of ≥30 bpm (beats/min) with symptoms related to upright posture. Active stand (STAND) and passive head-up tilt (TILT) produce different physiological responses. We hypothesized these different responses would affect the ability of individuals to achieve the POTS HR increase criterion. Patients with POTS (n=15) and healthy controls (n=15) underwent 30 min of tilt and stand testing. ΔHR values were analysed at 5 min intervals. ROC (receiver operating characteristic) analysis was performed to determine optimal cut point values of ΔHR for both tilt and stand. Tilt produced larger ΔHR than stand for all 5 min intervals from 5 min (38±3 bpm compared with 33±3 bpm; P=0.03) to 30 min (51±3 bpm compared with 38±3 bpm; P

The quality of pelleted feeds is dependent on several variables among which formulation is recognized as having the heaviest influence. An experiment was conducted to investigate the functional properties of feed ingredient components when these ingredients were blended at different proportions on the physical quality of pelleted feeds as measured by the pellet durability index (PDI). Thirteen treatments consisting of different inclusion levels of corn, soybean meal, and soybean oil were designed and a total of 18 batches manufactured, processed, and tested for PDI. Three-dimensional plots were used to depict the relationships between composition of the formulations and PDI. Results showed only a weak dependence of the response on the starch levels in the formulas and the degree of starch gelatinization. Protein, especially from soybean meal, had a positive effect on PDI, whereas a strong negative effect was observed following fat inclusion in the mixer at levels >6.5%. Empirical equations devise...

Background To evaluate the relation between elective cesarean section and vertical transmission of human immunodeficiency virus type 1 (HIV-1), we performed a meta-analysis using data on individual patients from 15 prospective cohort studies. Methods North American and European studies of at least 100 mother-child pairs were included in the meta-analysis. Uniform definitions of modes of delivery were used. Elective cesarean sections were defined as those performed before onset of labor and rupture of membranes. Multivariate logistic-regression analysis was used to adjust for other factors known to be associated with vertical transmission. Results The primary analysis included data on 8533 mother-child pairs. After adjustment for receipt of antiretroviral therapy, maternal stage of disease, and infant birth weight, the likelihood of vertical transmission of HIV-1 was decreased by approximately 50 percent with elective cesarean section, as compared with other modes of delivery (adjusted odds ratio, 0.43; 95 percent confidence interval, 0.33 to 0.56). The results were similar when the study population was limited to those with rupture of membranes shortly before delivery. The likelihood of transmission was reduced by approximately 87 percent with both elective cesarean section and receipt of antiretroviral therapy during the prenatal, intrapartum, and neonatal periods, as compared with other modes of delivery and the absence of therapy (adjusted odds ratio, 0.13; 95 percent confidence interval, 0.09 to 0.19). Among mother-child pairs receiving antiretroviral therapy during the prenatal, intrapartum, and neonatal periods, rates of vertical transmission were 2.0 percent among the 196 mothers who underwent elective cesarean section and 7.3 percent among the 1255 mothers with other modes of delivery. Conclusions The results of this meta-analysis suggest that elective cesarean section reduces the risk of transmission of HIV-1 from mother to child independently of the effects of treatment with zidovudine.

Muscle tone was tested at the shoulders and wrists of 49 randomly selected poststroke patients with the use of resting joint position (SJP and WJP), resistance to passive movement or stiffness (SRM and WRM), and angle of appearance of resistance (SAR and WAR). Subjects were tested while seated with their arm supported in a suspension sling adapted for free movement. Five of the first and immediately repeated measurement pairs showed strong correlations and interrater reliability (SJP, .839; WJP, .900; SRM, .886; WRM, .904; SAR, .884 [p < .05]). The sixth (WAR) showed moderate reliability (.618, p < .05). Resting joint position measurements were most reliable among subjects with higher tone. The joint first measured had a slight order effect on SRM among subjects with higher muscle tone. Its second measurements were slightly increased over the first among those subjects whose shoulders were measured first and slightly reduced when measured immediately after the wrist. Reliable means of clinical evaluation of muscle tone at the shoulder and wrist are available if the influence of level of tone and the mutual influence of muscles tested are prudently considered.

The scientific and policy worlds have different goals, which can lead to different standards for what constitutes "proof" of a change or phenomena, and different approaches for characterizing and conveying uncertainty and risk. These differences can compromise effective communication among scientists, policymakers, and the public, and constrain the types of socially compelling questions scientists are willing to address. In this paper, we review a set of approaches for dealing with uncertainty, and illustrate some of the errors that arise when science and policy fail to coordinate correctly. We offer a set of recommendations, including restructuring of science curricula and establishment of science-policy forums populated by leaders in both arenas, and specifically constituted to address problems of uncertainty.

Natural Values: Exploring Options for Enhancing Ecosystem Services in the Goulburn Broken Catchment is the culmination of four years work and the first of its kind in Australia. It began with a vision; to reconnect Australians with the environment that surrounds them and supports their life choices. In essence to change the way people view the environment, not as a resource to be taken for granted but one to be valued for the free services it provides and one worth investing in. Whilst it was always an ambitious goal the project has made tremendous progress in promoting the concept and contributing to the science.

The macerated stillborn fetus represents at least one third of all perinatal deaths. Microscopic examination of these specimens is often unrewarding. We have reported a clinically unsuspected cytomegalovirus infection in a second trimester macerated fetus. Cells suggestive of CMV inclusions were identified by light microscopy, but electron microscopy confirmed the presence of viral infection and proved valuable in making the diagnosis even though necrosis was severe.