This review examines the direct effects of climate change on insect herbivores. Temperature is identified as the dominant abiotic factor directly affecting herbivorous insects. There is little ...evidence of any direct effects of CO2 or UVB. Direct impacts of precipitation have been largely neglected in current research on climate change. Temperature directly affects development, survival, range and abundance. Species with a large geographical range will tend to be less affected. The main effect of temperature in temperate regions is to influence winter survival; at more northerly latitudes, higher temperatures extend the summer season, increasing the available thermal budget for growth and reproduction. Photoperiod is the dominant cue for the seasonal synchrony of temperate insects, but their thermal requirements may differ at different times of year. Interactions between photoperiod and temperature determine phenology; the two factors do not necessarily operate in tandem. Insect herbivores show a number of distinct life‐history strategies to exploit plants with different growth forms and strategies, which will be differentially affected by climate warming. There are still many challenges facing biologists in predicting and monitoring the impacts of climate change. Future research needs to consider insect herbivore phenotypic and genotypic flexibility, their responses to global change parameters operating in concert, and awareness that some patterns may only become apparent in the longer term.
Although there is extensive evidence confirming the predictive validity of situational judgement tests (SJTs) in medical education, there remains a shortage of evidence for their predictive validity ...for performance of postgraduate trainees in their first role in clinical practice. Moreover, to date few researchers have empirically examined the complementary roles of academic and non-academic selection methods in predicting in-role performance. This is an important area of enquiry as despite it being common practice to use both types of methods within a selection system, there is currently no evidence that this approach translates into increased predictive validity of the selection system as a whole, over that achieved by the use of a single selection method. In this preliminary study, the majority of the range of scores achieved by successful applicants to the UK Foundation Programme provided a unique opportunity to address both of these areas of enquiry. Sampling targeted high (>80th percentile) and low (<20th percentile) scorers on the SJT. Supervisors rated 391 trainees’ in-role performance, and incidence of remedial action was collected. SJT and academic performance scores correlated with supervisor ratings (
r
= .31 and .28, respectively). The relationship was stronger between the SJT and in-role performance for the low scoring group (
r
= .33, high scoring group
r
= .11), and between academic performance and in-role performance for the high scoring group (
r
= .29, low scoring group
r
= .11). Trainees with low SJT scores were almost five times more likely to receive remedial action. Results indicate that an SJT for entry into trainee physicians’ first role in clinical practice has good predictive validity of supervisor-rated performance and incidence of remedial action. In addition, an SJT and a measure of academic performance appeared to be complementary to each other. These initial findings suggest that SJTs may be more predictive at the lower end of a scoring distribution, and academic attainment more predictive at the higher end.
Identification of areas contributing disproportionately high amount of pollutants （i.e., critical source areas （CSAs）） to streams is important to efficiently and effectively target best management ...practices （BMPs）. Process-based models are commonly used to identify CSAs and evaluate the impact of alternative management practices on pollutant load reductions. The objective of this study was to use the Soil and Watershed Assessment Tool （SWAT） to identify CSAs at the subwatershed level and evaluate the impact of alternative BMPs on sediment and total phosphorus （TP） load reductions in the Pleasant Valley watershed （50 km2） in South Central Wisconsin （USA）. The Nash-Sutcliffe efficiency, percent bias, and coefficient of determination ranged from 0.58 to 0.71, - 12.87 to 38.33, and 0.67 to 0.79, respectively, indicating that SWAT was able to predict stream flow, sediment and TP loadings at a monthly time-step with sufficient accuracy. Based on the SWAT simulation results, annual average （2006-2012） subwatershed yield for sediment and TP ranged from 0.0{5 to 3.14tonsha-1 yr and 0.04 to 1.9 kg ha- 1 yr- 1 respectively. The croplands were the major source of sediment and TP in this watershed （ 〉 84%）. Reduction in sediment and TP loading ranged from 6670 to 9970 at the subwatersbed level after conversion of croplands to Conservation Reserve Program （CRP） grasslands in subwatersheds identified as CSAs. On the other hand, reduction in sediment and TP loading with implementation of no-till practices ranged from only 14% to 25%. At the watershed outlet, sediment and TP loading reduction was 〈 15% after conversion of croplands to CRP grasslands and implementation of no-till practices because only about 870 of the watershed area was targeted for BMPs and/or resuspension of sediment deposited on the stream bed masked the downstream improvements in water quality.
The blood-brain barrier (BBB) comprises the foremost protective barrier in the brain and is composed in part of a layer of microvascular endothelial cells that line the capillaries surrounding the ...brain. Here, we describe a human three-dimensional (3-D) cell-based model of the BBB microvascular endothelium that recapitulates properties of these cells
, including physiologically relevant transcriptional profiles, the capacity to induce potent antimicrobial innate immune signaling, and the ability to resist infection by diverse RNA viruses, including members of the enterovirus (coxsackievirus B, echovirus 11, enterovirus 71, poliovirus) and flavivirus (dengue virus, Zika virus ZIKV) families. We show that disruption of apical tight junctions by proinflammatory cytokine tumor necrosis factor alpha (TNF-α) sensitizes 3-D-cultured BBB cells to ZIKV infection and that 3-D derived BBB cells can be used to model the transmigration of ZIKV-infected monocytes across the endothelial barrier to access underlying astrocytes. Taken together, our findings show that human BBB microvascular endothelial cells cultured in 3-D can be used to model the mechanisms by which RNA viruses access the central nervous system (CNS), which could be used for the development and screening of therapeutics to limit this event.
Neurotropic viral infections are significant sources of global morbidity and mortality. The blood-brain barrier (BBB) is composed in part of a layer of microvascular endothelial cells and functions to restrict viral access to the brain.
models that recapitulate many of the properties of the human BBB endothelium are lacking, particularly with respect to the unique cellular and immunological mechanisms by which these cells restrict viral infections of the brain. Here, we developed a three-dimensional cell culture model that recapitulates many of the morphological and functional properties of the BBB microvasculature and apply this model to the study of RNA virus infections. The model we describe can therefore be used to study a variety of aspects of BBB physiology, including the mechanisms by which viruses might access the CNS, and could be used for the development and screening of antiviral therapeutics to limit this important step in viral pathogenesis.
The Wisconsin Phosphorus Index (WPI) is one of several P indices in the United States that use equations to describe actual P loss processes. Although for nutrient management planning the WPI is ...reported as a dimensionless whole number, it is calculated as average annual dissolved P (DP) and particulate P (PP) mass delivered per unit area. The WPI calculations use soil P concentration, applied manure and fertilizer P, and estimates of average annual erosion and average annual runoff. We compared WPI estimated P losses to annual P loads measured in surface runoff from 86 field-years on crop fields and pastures. As the erosion and runoff generated by the weather in the monitoring years varied substantially from the average annual estimates used in the WPI, the WPI and measured loads were not well correlated. However, when measured runoff and erosion were used in the WPI field loss calculations, the WPI accurately estimated annual total P loads with a Nash–Sutcliffe Model Efficiency (NSE) of 0.87. The DP loss estimates were not as close to measured values (NSE = 0.40) as the PP loss estimates (NSE = 0.89). Some errors in estimating DP losses may be unavoidable due to uncertainties in estimating on-farm manure P application rates. The WPI is sensitive to field management that affects its erosion and runoff estimates. Provided that the WPI methods for estimating average annual erosion and runoff are accurately reflecting the effects of management, the WPI is an accurate field-level assessment tool for managing runoff P losses.
Simultaneous PET-MRI is used to compare patterns of cerebral hypometabolism and atrophy in six different dementia syndromes.
The primary objective was to conduct an initial exploratory study ...regarding the concordance of atrophy and hypometabolism in syndromic variants of Alzheimer's disease (AD) and frontotemporal dementia (FTD). The secondary objective was to determine the effect of image analysis methods on determination of atrophy and hypometabolism.
PET and MRI data were acquired simultaneously on 24 subjects with six variants of AD and FTD (n = 4 per group). Atrophy was rated visually and also quantified with measures of cortical thickness. Hypometabolism was rated visually and also quantified using atlas- and SPM-based approaches. Concordance was measured using weighted Cohen's kappa.
Atrophy-hypometabolism concordance differed markedly between patient groups; kappa scores ranged from 0.13 (nonfluent/agrammatic variant of primary progressive aphasia, nfvPPA) to 0.49 (posterior cortical variant of AD, PCA). Heterogeneity was also observed within groups; the confidence intervals of kappa scores ranging from 0-0.25 for PCA to 0.29-0.61 for nfvPPA. More widespread MRI and PET changes were identified using quantitative methods than on visual rating.
The marked differences in concordance identified in this initial study may reflect differences in the molecular pathologies underlying AD and FTD syndromic variants but also operational differences in the methods used to diagnose these syndromes. The superior ability of quantitative methodologies to detect changes on PET and MRI, if confirmed on larger cohorts, may favor their usage over qualitative visual inspection in future clinical diagnostic practice.
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