Enhanced Migratory Waterfowl Distribution Modeling by Inclusion of Depth to Water Table Data

In addition to being used as a tool for ecological understanding, management and conservation of migratory waterfowl rely heavily on distribution models; yet these models have poor accuracy when compared to models of other bird groups. The goal of this study is to offer methods to enhance our ability to accurately model the spatial distributions of six migratory waterfowl species. This goal is accomplished by creating models based on species-specific annual cycles and introducing a depth to water table (DWT) data set. The DWT data set, a wetland proxy, is a simulated long-term measure of the point either at or below the surface where climate and geological/topographic water fluxes balance. For species occurrences, the USGS' banding bird data for six relatively common species was used. Distribution models are constructed using Random Forest and MaxEnt. Random Forest classification of habitat and non-habitat provided a measure of DWT variable importance, which indicated that DWT is as important, and often more important, to model accuracy as temperature, precipitation, elevation, and an alternative wetland measure. MaxEnt models that included DWT in addition to traditional predictor variables had a considerable increase in classification accuracy. Also, MaxEnt models created with DWT often had higher accuracy when compared with models created with an alternative measure of wetland habitat. By comparing maps of predicted probability of occurrence and response curves, it is possible to explore how different species respond to water table depth and how a species responds in different seasons. The results of this analysis also illustrate that, as expected, all waterfowl species are tightly affiliated with shallow water table habitat. However, this study illustrates that the intensity of affiliation is not constant between seasons for a species, nor is it consistent between species

Quality of care assessment in geriatric evaluation and management units: construction of a chart review tool for a tracer condition

<p>Abstract</p> <p>Background</p> <p>The number of elderly people requiring hospital care is growing, so, quality and assessment of care for elders are emerging and complex areas of research. Very few validated and reliable instruments exist for the assessment of quality of acute care in this field. This study's objective was to create such a tool for Geriatric Evaluation and Management Units (GEMUs).</p> <p>Methods</p> <p>The methodology involved a reliability and feasibility study of a retrospective chart review on 934 older inpatients admitted in 49 GEMUs during the year 2002–2003 for fall-related trauma as a tracer condition. Pertinent indicators for a chart abstraction tool, the Geriatric Care Tool (GCT), were developed and validated according to five dimensions: access to care, comprehensiveness, continuity of care, patient-centred care and appropriateness. Consensus methods were used to develop the content. Participants were experts representing eight main health care professions involved in GEMUs from 19 different sites. Items associated with high quality of care at each step of the multidisciplinary management of patients admitted due to falls were identified. The GCT was tested for intra- and inter-rater reliability using 30 medical charts reviewed by each of three independent and blinded trained nurses. Kappa and agreement measures between pairs of chart reviewers were computed on an item-by-item basis.</p> <p>Results</p> <p>Three quarters of 169 items identifying the process of care, from the case history to discharge planning, demonstrated good agreement (kappa greater than 0.40 and agreement over 70%). Indicators for the appropriateness of care showed less reliability.</p> <p>Conclusion</p> <p>Content validity and reliability results, as well as the feasibility of the process, suggest that the chart abstraction tool can gather standardized and pertinent clinical information for further evaluating quality of care in GEMU using admission due to falls as a tracer condition. However, the GCT should be evaluated in other models of acute geriatric units and new strategies should be developed to improve reliability of peer assessments in characterizing the quality of care for elderly patients with complex conditions.</p

Viability of Bifidobacterium longum in cheddar cheese curd during manufacture and storage: effect of microencapsulation and point of inoculation

International audienceThe goal of this study was to assess the effect of methods of inoculation on the viability of probiotic bacteria during cheddar cheese manufacture as well as their stability during storage. Bifidobacterium longum ATCC 15708 was freeze-dried and microencapsulated by spray-coating. The effect of inoculation of free whole cell or microencapsulated cells at three points during manufacture (milk before renneting, at cheddaring or at salting) on the viable counts in cheese and whey was investigated. Microencapsulation had no effect on viable counts, chemical parameters (lactose, lactic acid, total nitrogen, nitrogen soluble in TCA, moisture) or sensory properties during manufacturing or storage of the fresh cheeses for 14 days. Inoculation of the bifidobacteria in milk before renneting resulted in higher viable counts in comparison to other points of inoculation. Bifidobacteria added at the salting step, which survived pressing, were subsequently more stable during storage than those inoculated in milk. The stability of B. longum 15708 during storage was greater in the pressed cheeses that in the free curds. The results of this study provides technological data for cheese makers on the optimum point of inoculation as well as the benefit of pressing the curds in order to ensure high levels of probiotics in fresh cheddar cheese

An evaluation of the self-assembly enhancing properties of cell-derived hexameric amyloid-β

A key hallmark of Alzheimer’s disease is the extracellular deposition of amyloid plaques composed primarily of the amyloidogenic amyloid-β (Aβ) peptide. The Aβ peptide is a product of sequential cleavage of the Amyloid Precursor Protein, the first step of which gives rise to a C-terminal Fragment (C99). Cleavage of C99 by γ-secretase activity releases Aβ of several lengths and the Aβ42 isoform in particular has been identified as being neurotoxic. The misfolding of Aβ leads to subsequent amyloid fibril formation by nucleated polymerisation. This requires an initial and critical nucleus for self-assembly. Here, we identify and characterise the composition and self-assembly properties of cell-derived hexameric Aβ42 and show its assembly enhancing properties which are dependent on the Aβ monomer availability. Identification of nucleating assemblies that contribute to self-assembly in this way may serve as therapeutic targets to prevent the formation of toxic oligomers