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Increased temperatures associated with urbanization (the "urban heat island" effect) have been shown to impact a wide range of traits across diverse taxa. At the same time, climatic conditions vary at fine spatial scales within habitats due to factors including shade from shrubs, trees, and built structures. Patches of shade may function as microclimate refugia that allow species to occur in habitats where high temperatures and/or exposure to ultraviolet radiation would otherwise be prohibitive. However, the importance of shaded microhabitats for interactions between species across urbanized landscapes remains poorly understood. Weedy plants and their foliar pathogens are a tractable system for studying how multiple scales of climatic variation influence infection prevalence. Powdery mildew pathogens are particularly well suited to this work, as these fungi can be visibly diagnosed on leaf surfaces. We studied the effects of shaded microclimates on rates of powdery mildew infection on Plantago host species in (1) "pandemic pivot" surveys in which undergraduate students recorded shade and infection status of thousands of plants along road verges in urban and suburban residential neighborhoods, (2) monthly surveys of plant populations in 22 parks along an urbanization gradient, and (3) a manipulative field experiment directly testing the effects of shade on the growth and transmission of powdery mildew. Together, our field survey results show strong positive effects of shade on mildew infection in wild Plantago populations across urban, suburban, and rural habitats. Our experiment suggests that this relationship is causal, where microclimate conditions associated with shade promote pathogen growth. Overall, infection prevalence increased with urbanization despite a negative association between urbanization and tree cover at the landscape scale. These findings highlight the importance of taking microclimate heterogeneity into account when establishing links between macroclimate or land use context and prevalence of disease. [ABSTRACT FROM AUTHOR]

Productivity in the Arctic is expected to increase as temperatures and the number of open water days rise. With this increased productivity, the coastal shelves of the Arctic Ocean may act as a sink for atmospheric carbon. However, this storage is dependent on a sufficient nitrogen (N) supply and current literature on biogeochemical rates of N uptake in this region is severely limited. Here, we report the spatial extent and rate at which the aquatic microbial community utilizes inorganic and organic N substrates in the Alaskan Arctic during late summer. Uptake rates (> 0.3 μm) were measured in 2016 and 2017 using isotopically labeled ammonium (NH4+), nitrate (NO3−), urea, and mixed algal amino acids. Rates of NH4+ regeneration were also measured to investigate the contribution of remineralized N to primary production. Primary production was estimated using isotopically labeled bicarbonate. We found that N species uptake varied by location. Although NH4+ was the form of N taken up at the greatest rate at most sites, we also found that uptake rates of urea could be greater than NO3− and that amino acid uptake was widespread. Supporting previous studies, NO3− uptake rates were correlated with primary production rates. Variability in nutrient reservoirs and sampling conditions in the Chukchi Sea between the 2 yr were responsible for some of the variances observed in estimated NH4+ recycling rates and primary production. Understanding which N sources support this late‐season primary production requires obtaining uptake rates for a diverse range of inorganic and organic N substrates. [ABSTRACT FROM AUTHOR]

When cut scores for classifications occur on the total score scale, popular methods for estimating classification accuracy (CA) and classification consistency (CC) require assumptions about a parametric form of the test scores or about a parametric response model, such as item response theory (IRT). This article develops an approach to estimate CA and CC nonparametrically by replacing the role of the parametric IRT model in Lee's classification indices with a modified version of Ramsay's kernel-smoothed item response functions. The performance of the nonparametric CA and CC indices are tested in simulation studies in various conditions with different generating IRT models, test lengths, and ability distributions. The nonparametric approach to CA often outperforms Lee's method and Livingston and Lewis's method, showing robustness to nonnormality in the simulated ability. The nonparametric CC index performs similarly to Lee's method and outperforms Livingston and Lewis's method when the ability distributions are nonnormal. [ABSTRACT FROM AUTHOR]

Quinn N, Shulman A, Knifton L, Byrne P. The impact of a national mental health arts and film festival on stigma and recovery. This study aims to evaluate the impact of a national mental health arts festival for the general public, encompassing a wide variety of art forms and themes. An evaluation was undertaken with 415 attendees from 20 different events, combining qualitative and quantitative approaches. The findings demonstrate positive impact on the relationship between arts and mental health. Events increased positive attitudes, including positive representations of people's contributions, capabilities and potential to recover. They did not decrease negative attitudes. Intended behaviour change was modest and one film event increased audience perceptions of dangerousness. The paper argues that the arts can change stigma by constructing shared meanings and engaging audiences on an emotional level. Carefully programmed, collaborative, community-based arts festivals should form an integral part of national programmes to address stigma and to promote mental health and wellbeing, alongside traditional social marketing and public education approaches. [ABSTRACT FROM AUTHOR]

Here, we present the first study to investigate the seasonal importance of amino acid-nitrogen (N) to Arctic near shore microbial communities. We measured primary productivity and the uptake of ammonium, nitrate, urea, and amino acids in two size fractions (> 3 μm and approximately 0.7-3 μm), as well as ammonium regeneration and nitrification using 15N and 13C tracer approaches in the near-shore waters of the Chukchi Sea, during January, April, and August for two consecutive years. At discrete depths, nitrate comprised 46-78% of the total dissolved N pool during January and April but only 2-6% during August. Dissolved organic N (DON) concentrations increased between January and August though the carbon (C) : N (mol : mol) of the DON pool declined. Of the substrates tested, amino acids supported the bulk of both N and C nutrition in both size fractions during January and April (ice-covered). Urea generally had the lowest uptake rate under ice-covered conditions; uptake of urea-C was only detectable in August. Though previous Arctic studies focused largely on nitrate, we found nitrate uptake was generally lower than other substrates tested. The sharp decline in nitrate concentration between April and August, however, indicates a drawdown of nitrate during that period. Rates of ammonium uptake were highest in August, when it was the dominant N substrate used. During all sample periods, rates of ammonium regeneration were sufficient to supply ammonium demand. Rates of nitrification varied between sample periods, however, with much higher rates seen in January and April. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 50-year-old man with erectile dysfunction. Topics discussed include his urinary symptoms including increased frequency, nocturia and urgency; family history of parkinsonism, frontotemporal dementia, and motor neuron disease; and medical screening of his brain using the magnetic resonance imaging (MRI).

The release of fresh water from major impoundments to meet the requirements of estuaries has become a recognized need and methodologies to define appropriate release strategies have become an urgent priority in some parts of the world. A recruitment index for juvenile marine fish is presented, based on information relating to the preferred recruitment periods for 27 species, as well as the extent of dependency of these species on estuaries. The status of the estuary mouth (i.e. open or closed) and the longitudinal salinity differences (i.e. the difference between the salinity at the estuary head and the mouth) in the estuary are obtained from a hydrodynamic model of the estuary. The recruitment index integrates this information to provide an indication of potential recruitment (or recruitment opportunity). This index was applied in a case study of the Great Brak Estuary, South Africa, and a distinct decrease in the recruitment index was associated with a reduction in freshwater inflow. In the estuary modelled, annual run-off could be halved without an appreciable decrease in the fish recruitment index (FRI), but with a potentially sharp decline in fish recruitment thereafter. While the index represented recruitment opportunity rather than actual recruitment, it does at least provide an indication of where ecological risk is likely to increase substantially. Since the index integrates the current understanding with respect to the key processes which regulate recruitment of juvenile marine fish into estuaries, it is suggested that it has the potential to fulfil a vital role in identifying appropriate freshwater release policies for impoundments in South Africa. [ABSTRACT FROM AUTHOR]

The Arctic is warming at a rate nearly twice the global average, leading to thawing permafrost, increased coastal erosion, and enhanced delivery of riverine terrestrially-derived dissolved organic matter (tDOM) to coastal waters. This humic-rich tDOM has the ability to attenuate light required for photosynthesis and stimulate heterotrophic growth by supplying a source of labile organic carbon. Due to tDOM's high carbon to nitrogen (C : N) ratio, additional nitrogen is required for microorganisms to utilize this excess carbon for growth, thus exacerbating competition between autotrophs and heterotrophs for limiting nutrients and potentially reducing primary production. The effect of Arctic tDOM additions on nitrate uptake by two microplankton size fractions in the coastal Chukchi Sea was quantified using 15N tracer methods. To assess the biogeochemical vs. spectral impacts of tDOM, the uptake incubations were amended with either tDOM or light attenuating films that mimic light absorption by the tDOM. Nitrate uptake and primary production rates in the larger, predominantly phytoplankton, size fraction generally decreased with increasing tDOM additions. The change in light attenuation alone accounted for a ∼ 50% reduction in nitrate uptake. Responses in the smaller size fraction varied seasonally with tDOM additions stimulating uptake in spring and suppressing it in summer. The largest variation in summer nitrate uptake can be explained by the shared effect of biogeochemistry and light attenuation. Therefore, large increases in tDOM delivery currently occurring and predicted to increase in the coastal Arctic, could reduce primary production, broadly impact nitrogen and carbon cycling, and affect higher trophic levels. [ABSTRACT FROM AUTHOR]

We assessed the accuracy of clinical diagnosis of progressive supranuclear palsy (PSP, Steele-Richardson-Olszewski disease) and the validity of existing sets of clinical diagnostic criteria for PSP (see Appendix) using neuropathologically examined cases from the Queen Square Brain Bank for Neurological Disorders. Diagnosis of PSP was made by 40 different physicians, and 60 cases clinically diagnosed as PSP when last assessed in life were studied. In 47 cases (78%), the diagnosis of PSP was confirmed pathologically. False-positive diagnoses included Parkinson's disease with significant additional cortical Lewy body (n = 3) or Alzheimer (n = 1) pathology, multiple system atrophy (n = 4), and corticobasal degeneration, Pick's disease, motor neurone disease, cerebrovascular disease, and a sporadic case of frontotemporal dementia and parkinsonism linked to chromosome 17 (1 case each). Most cases of PSP were diagnosed accurately by neurologists at the final assessment. Although application of National Institute of Neurological Disorders and the Society for PSP possible category marginally improved the accuracy of initial clinical diagnosis, none of the existing operational criteria could significantly improve accuracy of the final clinical diagnosis. © 2003 Movement Disorder Society [ABSTRACT FROM AUTHOR]