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One of the most pressing questions in ecology and conservation centers on disentangling the relative impacts of concurrent global change drivers, climate and land-use/land-cover (LULC), on biodiversity. Yet studies that evaluate the effects of both drivers on species' winter distributions remain scarce, hampering our ability to develop full-annual-cycle conservation strategies. Additionally, understanding how groups of species differentially respond to climate versus LULC change is vital for efforts to enhance bird community resilience to future environmental change. We analyzed long-term changes in winter occurrence of 89 species across nine bird groups over a 90-year period within the eastern United States using Audubon Christmas Bird Count (CBC) data. We estimated variation in occurrence probability of each group as a function of spatial and temporal variation in winter climate (minimum temperature, cumulative precipitation) and LULC (proportion of group-specific and anthropogenic habitats within CBC circle). We reveal that spatial variation in bird occurrence probability was consistently explained by climate across all nine species groups. Conversely, LULC change explained more than twice the temporal variation (i.e., decadal changes) in bird occurrence probability than climate change on average across groups. This pattern was largely driven by habitat-constrained species (e.g., grassland birds, waterbirds), whereas decadal changes in occurrence probabilities of habitat-unconstrained species (e.g., forest passerines, mixed habitat birds) were equally explained by both climate and LULC changes over the last century. We conclude that climate has generally governed the winter occurrence of avifauna in space and time, while LULC change has played a pivotal role in driving distributional dynamics of species with limited and declining habitat availability. Effective land management will be critical for improving species' resilience to climate change, especially during a season of relative resource scarcity and critical energetic trade-offs.

Evaluation of protected area effectiveness is critical for conservation of biodiversity. Protected areas that prioritize biodiversity conservation are, optimally, located and managed in ways that support relatively large and stable or increasing wildlife populations. Yet evaluating conservation efficacy remains a challenging endeavor. We used an extensive community science data set, eBird, to evaluate the efficacy of protected areas for birds across the Gulf of Mexico and Atlantic coasts of the United States. We modeled trends (2007-2018) for 12 vulnerable waterbirds that use coastal areas during breeding or wintering. We compared two types of protected areas-sites where conservation organizations implemented active stewardship or management or both to reduce human disturbance (hereafter stewardship sites) and local, state, federal, and private protected areas managed to maintain natural land cover (hereafter protected areas)-as well as unprotected areas. We evaluated differences in trends between stewardship, protected, and unprotected areas across the Gulf and Atlantic coasts as a whole. Similar to a background sample, stewardship was known to occur at stewardship sites, but unknown at protected and unprotected areas. Four of 12 target species-Black Skimmer (Rynchops niger), Brown Pelican (Pelecanus occidentalis), Least Tern (Sternula antillarum), and Piping Plover (Charadrius melodus)-had more positive trends (two to 34 times greater) at stewardship sites than protected areas. Furthermore, five target species showed more positive trends at sites with stewardship programs than unprotected sites during at least one season, whereas seven species showed more positive trends at protected than unprotected areas. No species had more negative trends at stewardship sites than unprotected areas, and two species had more negative trends at protected than unprotected areas. Anthropogenic disturbance is a serious threat to coastal birds, and our findings demonstrate that stewardship to reduce its negative impacts helps ensure conservation of vulnerable waterbirds.La evaluación de la efectividad de las áreas protegidas es de suma importancia para la conservación de la biodiversidad. Las áreas protegidas que priorizan la conservación de la biodiversidad están, de manera óptima, ubicadas y manejadas de maneras que permiten el mantenimiento de poblaciones silvestres relativamente grandes y estables o en incremento. Aun así, la evaluación de la eficacia de la conservación todavía es un esfuerzo desafiante. Usamos un conjunto extensivo de datos de ciencia comunitaria, eBird, para evaluar la eficacia de las áreas protegidas a lo largo de las costas del Golfo de México y del Atlántico en los Estados Unidos. Modelamos las tendencias poblacionales (2007-2018) para doce aves acuáticas vulnerables que usan las áreas costeras durante la temporada de reproducción o de hibernación. Comparamos dos tipos de áreas protegidas - sitios en donde las organizaciones de conservación implementaron una gestión o manejo activo o ambos para reducir la perturbación humana (de ahora en adelante sitios de gestión) y las áreas protegidas locales, estatales, federales y privadas manejadas para mantener la cobertura natural del suelo (de ahora en adelante áreas protegidas) - así como las áreas desprotegidas. Evaluamos las diferencias en las tendencias entre las áreas de gestión, las protegidas y las desprotegidas a lo largo de las cosas del Golfo y del Atlántico como un todo. Similar a una muestra de fondo, se supo que la gestión ocurría en los sitios de gestión, pero no se sabía si ocurría en las áreas protegidas y desprotegidas. Cuatro de las doce especies analizadas - Rhynchops niger, Pelecanus occidentalis, Sternula antillarum y Charadrius melodus - tuvieron tendencias más positivas (2-34 veces mayor) en los sitios de gestión que en las áreas protegidas. Además, cinco especies mostraron más tendencias positivas en los sitios con programas de gestión que en los sitios desprotegidos al menos durante una temporada, mientras que siete especies mostraron más tendencias positivas en sitios protegidos que en las áreas desprotegidas. protegidas que en las desprotegidas. Ninguna especie tuvo más tendencias negativas en los sitios de gestión que en las áreas desprotegidas y dos especies tuvieron más tendencias negativas en las áreas protegidas que en las desprotegidas. La perturbación antropogénica es una amenaza seria para las aves costeras y nuestros hallazgos demuestran que la gestión para reducir sus impactos negativos ayuda a asegurar la conservación de aves acuáticas vulnerables.保护区有效性评估对生物多样性保护至关重要。优先保护生物多样性的保护区的选址和管理方式最好能够支持相对较大、保持稳定或不断增长的野生动物种群。然而, 保护效果的评估仍然是一项具有挑战性的工作。本研究使用社区科学数据集 eBird, 评估了横跨墨西哥湾和美国大西洋海岸的鸟类保护区的保护成效。我们估计了在沿海地区繁殖或越冬的 12 种易受危害的水鸟在 2007 - 2018 年的种群动态, 并比较了两种类型的保护区和未保护地区的情况, 其中保护区包括保护组织实施积极管理以减少人类干扰的地区)以下简称管理位点(, 以及由地方、州、联邦和私人设立的维持自然土地覆盖的保护区)以下简称保护区(。我们评估了整个墨西哥湾和大西洋沿岸得到管理、保护和未保护地区的鸟类种群动态差异。与背景样本类似, 管理位点得到了相应管理, 但保护区和不受保护的地区管理情况不明。我们关注的 12 个物种中有 4 个物种)黑剪嘴鸥 Rhynchops niger、褐鹈鹕 Pelecanus occidentalis 、小白额燕鸥 Sternula antillarum 和笛鸻 Charadrius melodus (在管理位点的种群比在保护区的种群增长更快)高 2 - 34 倍(。此外, 在至少一个季节内, 有 5 个目标物种在管理位点比在未保护地区表现出更积极的种群动态, 而7个目标物种在保护区比在未保护地区表现出更积极的种群动态。没有任何一个物种在管理位点比在未保护地区的种群有更明显的负面变化趋势, 而有 2 个物种在保护区比在未保护地区的种群有更负面的变化趋势。人为干扰会对沿海鸟类构成严重威胁, 而我们的研究结果表明, 通过管理工作减少人为干扰的负面影响有助于对易受干扰的水鸟进行保护。【翻译: 胡怡思; 审校: 聂永刚】.

Together climate and land-use change play a crucial role in determining species distribution and abundance, but measuring the simultaneous impacts of these processes on current and future population trajectories is challenging due to time lags, interactive effects and data limitations. Most approaches that relate multiple global change drivers to population changes have been based on occurrence or count data alone. We leveraged three long-term (1995-2019) datasets to develop a coupled integrated population model-Bayesian population viability analysis (IPM-BPVA) to project future survival and reproductive success for common loons Gavia immer in northern Wisconsin, USA, by explicitly linking vital rates to changes in climate and land use. The winter North Atlantic Oscillation (NAO), a broad-scale climate index, immediately preceding the breeding season and annual changes in developed land cover within breeding areas both had strongly negative influences on adult survival. Local summer rainfall was negatively related to fecundity, though this relationship was mediated by a lagged interaction with the winter NAO, suggesting a compensatory population-level response to climate variability. We compared population viability under 12 future scenarios of annual land-use change, precipitation and NAO conditions. Under all scenarios, the loon population was expected to decline, yet the steepest declines were projected under positive NAO trends, as anticipated with ongoing climate change. Thus, loons breeding in the northern United States are likely to remain affected by climatic processes occurring thousands of miles away in the North Atlantic during the non-breeding period of the annual cycle. Our results reveal that climate and land-use changes are differentially contributing to loon population declines along the southern edge of their breeding range and will continue to do so despite natural compensatory responses. We also demonstrate that concurrent analysis of multiple data types facilitates deeper understanding of the ecological implications of anthropogenic-induced change occurring at multiple spatial scales. Our modelling approach can be used to project demographic responses of populations to varying environmental conditions while accounting for multiple sources of uncertainty, an increasingly pressing need in the face of unprecedented global change.

BACKGROUND AND PURPOSE Fifteen percent of patients with myasthenia gravis (MG) are refractory to conventional treatment. Case reports and a few studies show probable benefit of rituximab in these cases. Our objective was to assess the efficacy and the safety of rituximab in patients with MG, in a multicentric real-life study. METHOD Inclusion criteria were: age > 18 years; MG with anti-acetylcholine receptor (AChR) antibodies, anti-muscle-specific kinase (MuSk) antibodies or significant decrement after repetitive nerve stimulation; Myasthenia Gravis Foundation of America (MGFA) class >II; refractory or steroid-dependent MG; and treatment with rituximab. Efficacy was assessed at 6 months using the MGFA-post-intervention status (PIS) score, the myasthenic muscle score (MMS) and the number of patients receiving steroids

Climate change poses an intensifying threat to many bird species and projections of future climate suitability provide insight into how species may shift their distributions in response. Climate suitability is characterized using ecological niche models (ENMs), which correlate species occurrence data with current environmental covariates and project future distributions using the modeled relationships together with climate predictions. Despite their widespread adoption, ENMs rely on several assumptions that are rarely validated in situ and can be highly sensitive to modeling decisions, precluding their reliability in conservation decision-making. Using data from a novel, large-scale community science program, we developed dynamic occupancy models to validate near-term climate suitability projections for bluebirds and nuthatches in summer and winter. We estimated occupancy, colonization, and extinction dynamics across species' ranges in the United States in relation to projected climate suitability in the 2020s, and used a Gibbs variable selection approach to quantify evidence of species-climate relationships. We also included a Bird Conservation Region strata-level random effect to examine among-strata variation in occupancy that may be attributable to land-use and ecoregional differences. Across species and seasons, we found strong evidence that initial occupancy and colonization were positively related to 2020 climate suitability, illustrating an independent validation of projections from ENMs across a large geographic area. Random strata effects revealed that occupancy probabilities were generally higher than average in core areas and lower than average in peripheral areas of species' ranges, and served as a first step in identifying spatial patterns of occupancy from these community science data. Our findings lend much-needed support to the use of ENM projections for addressing questions about potential climate-induced changes in species' occupancy dynamics. More broadly, our work highlights the value of community scientist observations for ground-truthing projections from statistical models and for refining our understanding of the processes shaping species' distributions under a changing climate.

The combined effects of global climate change and shifting patterns in land use have resulted in range shifts for many wildlife species, as favorable conditions have been created for species entering novel environments. Moose (Alces alces) are a forest specialist species but have recently expanded southward from their traditional range in the boreal and aspen parkland forests into the agriculture-dominated landscape of the Prairie Pothole Region in western Canada. We quantified habitat selection patterns for moose in an agriculture-dominated landscape in south-central Saskatchewan, Canada. We fitted 15 adult female moose with global positioning system collars and generated resource selection functions for summer (Jul–Sep) and winter (Dec–Feb). Our goal was to describe seasonal habitat selection patterns for moose using farmland. We buffered used and available locations by 100 m and quantified land cover types within buffers. To account for nonlinear habitat selection, we generated models with quadratic (squared) land cover terms. We found strong selection by moose for wetland and forest land cover types, a nonlinear selection of cereals with highest selection occurring at an intermediate percentage of cereals, and an avoidance of pulses (peas, beans, and lentils) in both seasons. Oilseeds were weakly selected in summer and weakly avoided in winter. Developed areas were avoided in both seasons. Our results suggest that moose select woody and tree-ringed wetlands for foraging and lay down in the wetlands or use the associated shade as thermoregulatory cover. The selection of these wetlands suggests a possible explanation for the successful expansion of moose into the Prairie Pothole Region. Consumption of crops by native ungulates is a cause for concern for local agricultural producers, with damage by moose increasing in south-central Saskatchewan. Our results have important management implications for managing human–wildlife conflict with wild ungulates in a novel ecosystem, with fenced exclosures around wetlands offering a potential solution to areas faced with extensive moose crop damage. The strong selection of wetland and forest land cover types emphasizes the importance of conservation efforts for the remaining wetlands and riparian buffers in the agriculture-dominated Prairie Pothole Region. © 2016 The Wildlife Society.

Many animal species exhibit spatiotemporal synchrony in population fluctuations, which may provide crucial information about ecological processes driving population change. We examined spatial synchrony and concordance among population trajectories of five aerial insectivorous bird species: chimney swift Chaetura pelagica, purple martin Progne subis, barn swallow Hirundo rustica, tree swallow Tachycineta bicolor, and northern rough-winged swallow Stelgidopteryx serripennis. Aerial insectivores have undergone severe guild-wide declines that were considered more prevalent in northeastern North America. Here, we addressed four general questions including spatial synchrony within species, spatial concordance among species, frequency of declining trends among species, and geographic location of declining trends. We used dynamic factor analysis to identify large-scale common trends underlying stratum-specific annual indices for each species, representing population trajectories shared by spatially synchronous populations, from 46 yr of North American Breeding Bird Survey data. Indices were derived from Bayesian hierarchical models with continuous autoregressive spatial structures. Stratum-level spatial concordance among species was assessed using cross-correlation analysis. Probability of long-term declining trends was compared among species using Bayesian generalized linear models. Chimney swifts exhibited declining trends throughout North America, with less severe declines through the industrialized Mid-Atlantic and Great Lakes regions. Northern rough-winged swallows exhibited declining trends throughout the west. Spatial concordance among species was limited, the proportion of declining trends varied among species, and contrary to previous reports, declining trends were not more prevalent in the northeast. Purple martins, barn swallows, and tree swallows exhibited synchrony across smaller spatial scales. The extensive within-species synchrony and limited concordance suggest that population trajectories of these aerial insectivores are responding to large-scale but complex and species- and region-specific environmental conditions (e.g. climate, land use). A single driver of trends for aerial insectivores as a guild appears unlikely.

Tropical rain forest understory insectivorous birds are declining, even in large forest reserves, yet the mechanisms remain unclear. Abundant large mammals can reshape forest structure, which degrades foraging microhabitat. We used six sites in Nicaragua, Costa Rica, and Panama with varying collared peccary (Pecari tajacu) density to test three linked hypotheses: (1) locally declining understory insectivores forage preferentially in liana tangles; (2) vine and liana density, cover, and frequency of dense tangles are lower in the presence of abundant collared peccaries; and consequently (3) abundant collared peccaries are associated with reduced understory insectivorous bird abundance. Three insectivores that declined at La Selva preferentially foraged in liana tangles: Checker-throated Antwren (Epinecrophylla fulviventris), Dot-winged Antwren (Microrhopias quixensis), and Ruddy-tailed Flycatcher (Terenotriccus erythrurus). Vine density, liana cover, liana tangle frequency, and forest cover were lower in the presence of collared peccaries relative to experimental mammal exclosures, with the greatest differences at La Selva Biological Station, Costa Rica. Across sites, five of seven vine and liana measures showed negative, curvilinear relationships with peccary densities. Vine and liana measures peaked at sites with intermediate peccary density, and were low at La Selva. Structural equation models suggest negative indirect effects of the collared peccaries on focal bird densities, mediated by vine and liana density, cover, or tangle frequency. Forest area and rainfall affected both lianas and birds, but collared peccaries also contributed to the reduced abundance of understory insectivores. Indirect effects such as that suggested here may occur even in large, protected forest reserves where large mammal communities are changing. Resumen A pesar de que las aves insectivoras de sotobosque de bosques lluviosos estan disminuyendo en los tropicos, e incluso en grandes reservas forestales, no se conocen los mecanismos causantes. Los grandes mamiferos en abundancia, pueden cambiar la estructura del bosque a traves de efectos troficos y no troficos, degradar microhabitats a traves del forrajeo. Utilizamos seis sitios en Nicaragua, Costa Rica y Panama con densidades diferentes de sainos (Pecari tajacu) para poner a prueba tres hipotesis con efecto en cadena: (1) varias aves insectivoras en disminucion forrajean preferiblemente en maranas de lianas, (2) la densidad de lianas y cobertura, y la frecuencia de maranas densas son mas bajos en la presencia de abundantes sainos, y en consecuencia (3) sainos abundantes se asocian con una reduccion de aves insectivoras de sotobosque. Tres aves insectivoras que disminuyeron en La Selva forrajearon preferiblemente en maranas de lianas: Epinecrophylla fulviventris, Microrhopias quixensis, y Terenotriccus erythrurus. La densidad de los bejucos, la cubierta de lianas, la frecuencia de maranas de lianas, y la cobertura de bosque fueron menores en presencia de sainos en relacion a exclusiones experimentales de mamiferos, con las mayores diferencias en Estacion Biologica La Selva, Costa Rica. En todos los sitios, cinco de las siete variables de bejucos y lianas mostraron relaciones negativas y curvilineas con densidades de sainos. Medidas de los bejucos y lianas fueron mayores en sitios con densidades intermedias de sainos, y estaban baja en La Selva. Los modelos de ecuaciones estructurales sugieren que los sainos tienen efectos indirectos negativos en la abundancia de aves focales, mediadas por la densidad y cubierta de bejucos y lianas o la frecuencia de maranas de lianas. El area del bosque y las lluvias tambien afectan a las lianas y a las aves, pero los sainos tambien contribuyeron a la disminucion de la abundancia de aves insectivoras de sotobosque. Los efectos indirectos documentados aqui pueden ocurrir incluso en grandes reservas forestales protegidas, donde las comunidades de mamiferos grandes estan cambiando.

Ecotoxicology research on polychlorinated biphenyl (PCB) mixtures has focused principally on short-term effects on reproduction, growth, and other physiological endpoints. Latent cognitive effects from early life exposure to low-level PCBs were examined in an avian model, the European starling (Sturnus vulgaris). Thirty-six birds, divided equally among 4 treatment groups (control = 0 µg, low = 0.35 µg, intermediate = 0.70 µg, and high = 1.05 µg Aroclor 1254/g body weight), were dosed 1 d through 18 d posthatch, then tested 8 mo to 9 mo later in captivity in an analog to an open radial arm maze. Birds were subject to 4 sequential experiments: habituation, learning, cue selection, and memory. One-half of the birds did not habituate to the test cage; however, this was not linked to a treatment group. Although 11 of the remaining 18 birds successfully learned, only 1 was from the high-dosed group. Control and low-dosed birds were among the only treatment groups to improve trial times throughout the learning experiment. High-dosed birds were slower and more error-prone than controls. Cue selection (spatial or color cues) and memory retention were not affected by prior PCB exposure. The results indicate that a reduction in spatial learning ability persists among birds exposed to Aroclor 1254 during development. This may have implications for migration ability, resource acquisition, and other behaviors relevant for fitness. Environ Toxicol Chem 2015;34:2513–2522. © 2015 SETAC

The Boreal Plains Ecozone (BPE) in Western Canada is expected to be an area of maximum ecological sensitivity in the 21st century. Successful climate adaptation and sustainable forest management require a better understanding of the interactions between hydrology, climate, and vegetation. This paper provides a perspective on the changing water cycle in the BPE from an interdisciplinary team of researchers, seeking to identify the critical knowledge gaps. Our review suggests the BPE will likely become drier and undergo more frequent disturbance and shifts in vegetation. The forest will contract to the north, though the southern boundary of the ecotone will remain in place. We expect detrimental impacts on carbon sequestration, water quality, wildlife, and water supplies. Ecosystem interactions are complex, and many processes are affected differently by warming and drying, thus the degree and direction of change is often uncertain. However, in the short term at least, human activities are the dominant source of change and are unpredictable but likely decisive. Current climate, hydrological, and ecological monitoring in the BPE are limited and inadequate to understand and predict the complex responses of the BPE to human activities and climate change. This paper provides a case study of how hydrological processes critically determine ecosystem functioning, and how our ability to predict system response is limited by our ability to predict changing hydrology. WIREs Water 2015, 2:505–521. doi: 10.1002/wat2.1098 For further resources related to this article, please visit the WIREs website.

Background The pathogenesis of diabetic peripheral neuropathy remains uncertain and nonenzymatic glycoxidation is one of the contributing mechanisms. The aim of this study was to assess the respective relationship of diabetic peripheral neuropathy with glycoxidation, compared with other identified risk factors, in patients with type 2 diabetes. Methods We included 198 patients with type 2 diabetes and high risk for vascular complications. Circulating concentrations of three advanced glycation end products (carboxymethyllysine, methyl-glyoxal-hydroimidazolone-1, pentosidine) and of their soluble receptor (sRAGE) were measured. Peripheral neuropathy was assessed by the neuropathy disability score and by the monofilament test and defined as either an abnormal monofilament test and/or a neuropathy disability score ≥6. Multivariate regression analyses were performed adjusting for potential confounding factors for neuropathy: age, gender, diabetes duration, current smoking, systolic blood pressure, waist circumference, height, peripheral arterial occlusive disease, glycated haemoglobin, estimated glomerular filtration rate and lipid profile. Results Prevalence of peripheral neuropathy was 20.7%. sRAGE and carboxymethyllysine were independently and positively associated with the presence of peripheral neuropathy. No significant association was found between peripheral neuropathy and methyl-glyoxal-hydroimidazolone-1 or pentosidine. Waist circumference, height and peripheral arterial occlusive disease were independently associated with peripheral neuropathy. Conclusions Carboxymethyllysine and sRAGE were independently associated with peripheral neuropathy in patients with type 2 diabetes. Although the conclusions are limited by the absence of a healthy control population, this study confirms the relationship between advanced glycoxidation and diabetic peripheral neuropathy, independently of other risk factors. Copyright © 2014 John Wiley & Sons, Ltd.

Array comparative genomic hybridization (aCGH) has progressively replaced conventional karyotype in the diagnostic strategy of intellectual disability (ID) and congenital malformations. This technique increases not only the diagnostic rate but also the possibility of finding unexpected variants unrelated to the indication of referral, namely incidental findings. The incidental finding of copy number variants (CNVs) located in X-linked genes in girls addresses the crucial question of genetic counseling in the family. We report here five cases of CNVs involving the dystrophin gene detected by aCGH in girls referred for developmental delay, without any family history of dystrophinopathy. The rearrangements included three in-frame deletions; one maternally and two paternally inherited, and two frameshift duplications: one de novo and one from undetermined inheritance. In two cases, the deletion identified in a girl was transmitted by the asymptomatic father. In the case of the maternally inherited deletion, prenatal diagnosis of dystrophinopathy was proposed for an ongoing pregnancy, whereas the cause of developmental delay in the index case remained unknown. Through these cases, we discussed the challenges of genetic counseling in the family, regarding the predictive issues for male individuals at risk for a muscular dystrophy without precise knowledge of the clinical consequences of some CNVs in the DMD gene.

Aim: Biologists increasingly recognize the roles of humans in ecosystems. Subsequently, many have argued that biodiversity conservation must be extended to environments that humans have shaped directly. Yet popular biogeographical frameworks such as biomes do not incorporate human land use, limiting their relevance to future conservation planning. 'Anthromes' map global ecological patterns created by sustained direct human interactions with ecosystems. In this paper, we set to understand how current conservation efforts are distributed across anthromes. Location: Global. Methods: We analysed the global distribution of IUCN protected areas and biodiversity hotspots by anthrome. We related this information to density of native plant species and density of previous ecological studies. Potential conservation opportunities in anthromes were then identified through global analysis and two case studies. Results: Protected areas and biodiversity hotspots are not distributed equally across anthromes. Less populated anthromes contain a greater proportion of protected areas. The fewest hotspots are found within densely settled anthromes and wildlands, which occur at the two extremes of human population density. Opportunities for representative protection, prioritization, study and inclusion of native species were not congruent. Main conclusions: Researchers and practitioners can use the anthromes framework to analyse the distribution of conservation practices at the global and regional scale. Like biomes, anthromes could also be used to set future conservation priorities. Conservation goals in areas directly shaped by humans need not be less ambitious than those in 'natural areas'.

Tritium concentrations in river and stream waters from different locations can be compared by normalizing them using the ratio of tritium concentrations in precipitation and surface water (Cp/Cs) in the study area. This study uses these ratios in a hydrological residence time context to make regional- and global-scale comparisons about river basin dynamics. Prior to the advent of nuclear weapons testing, the Cp/Cs ratio was greater than or equal to 1 everywhere because of the decay of tritium in the watershed after it was deposited by precipitation. After an initial increase in the ratios during the bomb peak, the ratio dropped to less than 1 for most surface waters in the following years. This post-bomb change in the ratio is due to the retention of the bomb-pulse water in watersheds on timescales that are long relative to the residence time of tritium in the atmosphere. Ratios were calculated for over 6500 measurements of tritium in river and stream waters compiled by the International Atomic Energy Agency. These measurements span the post-nuclear era (1940s to present) and include many long-term datasets, which make it possible to examine residence times of waters in watersheds on a global basis. Plotting Cp/Cs versus time shows that ratios tended to reach a minimum in approximately one to two decades after the bomb peak for most locations. This result suggests that changes affecting quantity and quality of river flows need to be assessed on a multi-decadal timescale. These long lag times have significant implications for assessing climate or land-use change impacts on a large number of river systems around the world. The continuing value of tritium in studying surface water systems for both the Southern and Northern Hemisphere is also demonstrated. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

Aims Pulse palpation and ankle brachial index are recommended to screen for peripheral arterial occlusive disease in people with diabetes. However, vascular calcification can be associated with false negative tests (arteriopathy present despite normal screening tests). We therefore studied the impact of peripheral vascular calcification on the performance of these tests. Methods This cross-sectional study included 200 people with diabetes at high risk of cardiovascular disease. The main exclusion factor was an estimated glomerular filtration rate

Soil–plant–atmosphere interactions strongly influence water movement in desert unsaturated zones, but little is known about how such interactions affect atmospheric release of subsurface water-borne contaminants. This 2-yr study, performed at the U.S. Geological Survey9s Amargosa Desert Research Site in southern Nevada, quantified the magnitude and spatiotemporal variability of tritium ( 3 H) transport from the shallow unsaturated zone to the atmosphere adjacent to a low-level radioactive waste (LLRW) facility. Tritium fluxes were calculated as the product of 3 H concentrations in water vapor and respective evaporation and transpiration water-vapor fluxes. Quarterly measured 3 H concentrations in soil water vapor and in leaf water of the dominant creosote-bush [ Larrea tridentata (DC.) Coville] were spatially extrapolated and temporally interpolated to develop daily maps of contamination across the 0.76-km 2 study area. Maximum plant and root-zone soil concentrations (4200 and 8700 Bq L −1 , respectively) were measured 25 m from the LLRW facility boundary. Continuous evaporation was estimated using a Priestley–Taylor model and transpiration was computed as the difference between measured eddy-covariance evapotranspiration and estimated evaporation. The mean evaporation/transpiration ratio was 3:1. Tritium released from the study area ranged from 0.12 to 12 μg d −1 and totaled 1.5 mg (8.2 × 10 10 Bq) over 2 yr. Tritium flux variability was driven spatially by proximity to 3 H source areas and temporally by changes in 3 H concentrations and in the partitioning between evaporation and transpiration. Evapotranspiration removed and limited penetration of precipitation beneath native vegetation and fostered upward movement and release of 3 H from below the root zone.

Understanding transport of tritium ( 3 H) in unsaturated zones is critical to evaluating options for waste isolation. Tritium typically is a large component of low-level radioactive waste (LLRW). Studies at the U.S. Geological Survey9s Amargosa Desert Research Site (ADRS) in Nevada investigate 3 H transport from a closed LLRW facility. Two boreholes are 100 and 160 m from the nearest waste trench and extend to the water table at 110 m. Soil-water vapor samples from the deep boreholes show elevated levels of 3 H at all depths. The objectives of this study were to (i) test source thermal and gas-advection mechanisms driving 3 H transport and (ii) evaluate model sensitivity to these mechanisms and to selected physical and hydraulic properties including porosity, tortuosity, and anisotropy. A two-dimensional numerical model incorporated a non-isothermal, heterogeneous domain of the unsaturated zone and instantaneous isotopic equilibrium. The TOUGH2 code was used; however, it required modification to account for temperature dependence of both the Henry9s law equilibrium constant and isotopic fractionation with respect to tritiated water. Increases in source temperature, pressure, and porosity enhanced 3 H migration, but failed to match measured 3 H distributions. All anisotropic simulations with a source pressure component resembled, in shape, the upper portion of the 3 H distribution of the nearest borehole. Isotopic equilibrium limited migration of 3 H, while effects of radioactive decay were negligible. A 500 Pa pressure increase above ambient pressure in conjunction with a high degree of anisotropy (1:100) was necessary for simulated 3 H transport to reach the nearest borehole.

Plant-based techniques were tested for field-scale evaluation of tritium contamination adjacent to a low-level radioactive waste (LLRW) facility in the Amargosa Desert, Nevada. Objectives were to (i) characterize and map the spatial variability of tritium in plant water, (ii) develop empirical relations to predict and map subsurface contamination from plant-water concentrations, and (iii) gain insight into tritium migration pathways and processes. Plant sampling [creosote bush, Larrea tridentata (Sesse & Moc. ex DC.) Coville] required one-fifth the time of soil water vapor sampling. Plant concentrations were spatially correlated to a separation distance of 380 m; measurement uncertainty accounted for

Trimethylpsoralen (TMP) is often used to treat skin diseases (i.e., psoriasis, vitiligo, etc.). This drug permeates moderately the skin barrier. In the present study, we investigated the effect of formulation on the improvement of TMP skin bioavailability. Three formulations were performed. Each form (liposomes, nanospheres, and EtOH solution) contained 0.05% of TMP. For each preparation, the quantity deposited on the skin surface was 250 µg (Q0). The TMP percutaneous penetration through ex-vivo human skin was processed by Franz® cells (n=4) using a human albumin solution (1.4% w/v) as receiver medium. The percentages of the extracted TMP that permeated through the skin and that were retained in the skin over 24 h, were calculated with respect to Q0. The values obtained were reported, respectively, as follows: EtOH solution (1.33 vs. 0.08%), liposomes (0.93 vs. 0.93%), and PLG-nanospheres (0.79 vs. 3.01%). So, considering the correlation between the cumulated amounts of TMP permeated through the skin and the TMP stocked in the skin, the nanosphere form showed the higher quantity of TMP accumulated in the skin structures. On the other hand, the maximum value of the flux (ng/cm2/h) in the steady state of TMP incorporated in each formulation was at 6 h for all formulations: 173.5±1.06 (EtOH solution) > 120.4±1.06 (liposomes) > 93.82±0.88 (PLG-nanospheres). These results indicate that the controlled release of TMP by incorporation in PLG-nanospheres may increase drug content in the skin, while maintaining a minimal percutaneous absorption. Finally, this work shows that the PLG-nanospheres could constitute a promising approach for controlling TMP release in order to maintain its topical activity. Drug Dev. Res. 61:86–94, 2004. © 2004 Wiley-Liss, Inc.

Time integrated measurements of the line emission of hydrogen-like and helium-like neon from a dense plasma focus device were performed. Relative intensities of Lyman-series emission from Ne X were measured end-on and side-on showing strong deviation from thermal equilibrium and indicating substantial population inversion between levels n = 5 and n = 2.

Complement is a system of functionally linked serum proteins that interact to exert biologic effects in inflammatory and immunologic processes. As part of a larger study with a potential topical antiallergic drug, we measured C3a des Arg and C5a des Arg in 13 patients with seasonal allergic rhinitis and in five nonatopic controls after placebo treatment. After 1 week of placebo treatment, a nasal allergen challenge with increasing doses of pollens was performed in both allergic subjects and controls. A symptom score method was used, and in returned nasal lavage fluid, the activity of C3a des Arg and C5a des Arg was measured. We found that allergen challenge in the allergic subjects induced nasal symptoms concomitantly with increased levels of C3a des Arg and C5a des Arg (P < 0.05). No increases either in symptoms or in the very low base-line levels of C3a des Arg and C5a des Arg were observed in the nonallergic controls. We conclude that the activation of the complement cascade is one part of the vasculature exudative response during the immediate allergic reaction in the upper airways. Because of their biologic potency, these proteins may be an essential part of the exudative response which perpetuates the ongoing inflammatory reaction.

Promiscuous binding has been considered to be a problem in the design and development of new drugs against a given disease. However, promiscuity in molecular recognition is not all bad news, and scientists are currently taking advantage of the emerging 'promiscuous binding' or 'multi-target approach' in medicinal chemistry.

Infectious animal tuberculosis, caused by Mycobacterium bovis, is a serious disease spread among numerous wildlife species in southern Africa where it has established itself as a significant problem in lions and other species conserved in the wildlife parks and game reserves of the region. There are also several infectious viral diseases of African lions, including canine distemper and feline immunodeficiency. Keywords: African wildlife; lions; tuberculosis; mycobacterium; canine distemper virus; feline immunodeficiency virus

Effective isolation of tritium (3H) and other contaminants at waste-burial facilities requires improved understanding of transport processes and pathways. Previous studies documented an anomalously widespread (i.e., theoretically unexpected) distribution of 3H (>400 m from burial trenches) in a dry, sub-root-zone gravelly layer (1–2-m depth) adjacent to a low-level radioactive waste (LLRW) burial facility in the Amargosa Desert, Nevada, that closed in 1992. The objectives of this study were to: (i) characterize long-term, spatiotemporal variability of 3H plumes; and (ii) quantify the processes controlling 3H behavior in the sub-root-zone gravelly layer beneath native vegetation adjacent to the facility. Geostatistical methods, spatial moment analyses, and mass flux calculations were applied to a spatiotemporally comprehensive, 10-yr data set (2001–2011). Results showed minimal bulk-plume advancement during the study period and limited Fickian spreading of mass. Observed spreading rates were generally consistent with theoretical vapor-phase dispersion. The plume mass diminished more rapidly than would be expected from radioactive decay alone, indicating net efflux from the plume. Estimates of upward 3H efflux via diffusive-vapor movement were >10× greater than by dispersive-vapor or total-liquid movement. Total vertical fluxes were >20× greater than lateral diffusive-vapor fluxes, highlighting the importance of upward migration toward the land surface. Mass-balance calculations showed that radioactive decay and upward diffusive-vapor fluxes contributed the majority of plume loss. Results indicate that plume losses substantially exceeded any continuing 3H contribution to the plume from the LLRW facility during 2001 to 2011 and suggest that the widespread 3H distribution resulted from transport before 2001.

The study of vertical mixing in Lake Tahoe by temperature and oxygen measurements is limited to the top layer of the lake, since vertical gradients are extremely small at greater depth. Below 200 m the temperature gradient is about -1.6 X lo-” “C m-l, with little or no seasonal variation. A tritium profile was taken at a midlake station in 1973 together with samples for measurements on lake chemistry. Oxygen, nitrate, total inorganic carbon, and pI1 showed the effects of photosynthetic activity to a depth of about 80 m, well below the thermocline; average planktonic composition was calculated from these data. Silicate and carbonate alkalinity profiles were essentially uniform, showing that biological removal is negligible in comparison to the rate of vertical mixing. Essentially no variation in tritium concentration with depth was observed. Tritium measurements and input estimates in Crater Lake were used to calculate tritium concentration in Lake Tahoe between 1954 and 1973 and to cstimatc a ratio in tritium input of 32% precipitation to 68% vapor exchange. The tritium profile gives strong evidence for at least occasional complete mixing of Lake Tahoe. The last complete mixing may have occurred in March 1973 and at least one other such event took place between 1964 and 1968. Lake Tahoe is a large, clear lake covering an area of 499 km2 at an altitude of 1,897 m in the Sierra Nevada. Due to its great depth (max, 501 m; mean depth, 313 m) the temperature and chemistry are virtually unaffected by seasonal variations below the top layer of the lake. Furthermore, hypolimnetic vertical gradients are extremely small, making the problem of vertical mixing difficult to study. In August 1973, personnel from the Scripps Institution of Oceanography and from the Division of Environmental Studies of the University of California at Davis tested at Lake Tahoe the use of oceanographic methods for limnological studies. We here discuss geochemical measurements with reference to vertical mixing problems. We thank A. Birket, T. L. Broadwell, F. Dixon, D. Hasha, I-1. W. Paerl, R. C. Richards, and C. Toy for assistance in the ficld’ On leave from Swiss Federal Institutes of Technology (EAWAG), Diibendorf, Switzerland. work, and B. Horn Wilson, E. Toby Linck, and E. Slater for their work in processing samples. We are grateful to J. Edmond who made the silicate analyses. This study was supported by a grant from the National Science Foundation to the Isotope Laboratory, Scripps Institution of Oceanography. The tritium analyses were supported by NSF grant 29952 (principal investigator 1-I. E. Suess). The Schweizcr Gewgsserschu tzstiftung provided a grant to D. Imboden. Temperature and geochemical data A complete profile of water samples for geochemical analysis was taken at a midlake station (Table 1). Depth was measured by standard hydrographic techniques and temperature with reversing thermometcrs. Oxygen samples were fixed immediately and ?pH samples .were stored in full bottles to avoid exposure to the atmosphere; both measurements were made at the Lake Tahoe laboratory of UC, (Davis) within LIMNOLOGY AND OCEANOGRAPHY 1039 NOVEMBER 1977, V. 22( 6)

The role of the land in the contemporary French-Canadian novel is worthy of study. In turn, the earth is the consoler, the sorceress, the adversary, the friend, and the guide of man. On the other hand, man considers himself part of the land which he loves and in which he takes great pride.)

No information is available on the structural requirements for the antitumor activity of sparsomycin, an antibiotic obtained from the fermentation broth of Streptomyces sparsogenes. Its high in vivo and in vitro activity, novel structure, and uncommon mode of action have, therefore, suggested the synthesis of analogs. This report describes the preparation and screening of a series of N-substituted 3-aryl acrylamides which are closely related to sparsomycin. Three compounds exhibited some tumor inhibition but insufficient to warrant further testing.

International audience; No abstract available