Equilibrium and dynamic moisture adsorption behaviour of bloodmeal based bioplastic

Bioplastics can be manufactured from protein or carbohydrate sources such as wheat gluten, corn, sun flower, keratin, casein, soy, gelatine and whey. A recently developed bioplastic is Novatein thermoplastic (NTP), which is produced from bloodmeal by adding water, urea, sodium sulphite, sodium dodecyl sulphate and tri-ethylene glycol (TEG), allowing it to be extruded and injection moulded. Bioplastics, compared to their petroleum counterparts, can readily adsorb or lose water, which then changes their physical properties such as tensile strength and glass transition temperature. NTP at different TEG and water contents was exposed to 20-85% relative humidity (RH) environments and change in mass recorded over 35 days to determine equilibrium and dynamic moisture adsorption behavior. Equilibrium behavior was modelled using modified Freundlich and Langmuir- Freundlich isotherms, and dynamic behavior modelled using Pilosof, Singh- ulshrestha, exponential, Langmuir-Freundlich and simple rate equations. Excellent fits were obtained for both isotherms and the last three rate equations gave best overall fits for dynamics. NTP adsorbed up to 28% by weight in water at 85% RH, reaching equilibrium within 20 days. Plastics with high TEG had a greater affinity for water but lower water adsorption rates, while dry plastic samples had a lower adsorption rate than wet samples. The two parameter Freundlich model and the exponential or simple rate model is recommended for modelling NTP equilibrium and dynamic water adsorption

CB2 Receptor Deficiency Increases Amyloid Pathology and Alters Tau Processing in a Transgenic Mouse Model of Alzheimer\u27s Disease

The endocannabinoid CB2 receptor system has been implicated in the neuropathology of Alzheimer\u27s disease (AD). In order to investigate the impact of the CB2 receptor system on AD pathology, a colony of mice with a deleted CB2 receptor gene, CNR2, was established on a transgenic human mutant APP background for pathological comparison with CB2 receptor-sufficient transgenic mice. J20 APP (PDGFB-APPSwInd) mice were bred over two generations with CNR2(-/-) (Cnr2(tm1Dgen)/J) mice to produce a colony of J20 CNR2(+/+) and J20 CNR2(-/-)mice. Seventeen J20 CNR2(+/+) mice (12 females, 5 males) and 16 J20 CNR2(-/-) mice (11 females, 5 males) were killed at 12 months, and their brains were interrogated for AD-related pathology with both biochemistry and immunocytochemistry (ICC). In addition to amyloid-dependent endpoints such as soluble A beta production and plaque deposition quantified with 6E10 staining, the effect of CB2 receptor deletion on total soluble mouse tau production was assayed by using a recently developed high-sensitivity assay. Results revealed that soluble A beta 42 and plaque deposition were significantly increased in J20 CNR2(-/-) mice relative to CNR2(1/1) mice. Microgliosis, quantified with ionized calcium-binding adapter molecule 1 (Iba-1) staining, did not differ between groups, whereas plaque associated microglia was more abundant in J20 CNR2(-/-) mice. Total tau was significantly suppressed in J20 CNR2(-/-) mice relative to J20 CNR2(+/+) mice. The results confirm the constitutive role of the CB2 receptor system both in reducing amyloid plaque pathology in AD and also support tehpotential of cannabinoid therapies targeting CB2 to reduce A beta; however, the results suggest that interventions may have a divergent effect on tau pathology

Unsteady skin friction experimentation in a large diameter pipe

Experimental data for the validation of theoretical models of unsteady skin friction are limited and are available only for a few low Reynolds number flow cases. There is a strong need for detailed measurements in flows at high Reynolds numbers. In addition, there is a need for a wider range of well-controlled acceleration/deceleration rates and detailed visualization of flow structure and profiles. To address these needs, a large-scale pipeline apparatus at Deltares, Delft, The Netherlands, has been used for unsteady skin friction experiments including acceleration, deceleration and acoustic resonance tests. The apparatus consists of a constant head tank, a horizontal 200 mm diameter pipe of changeable length (44 to 49 metres) and a control valve at the downstream end. In addition to standard instrumentation, two distinctive instruments have been used: hot-film wall shear stress sensors ("direct" measurement of wall shear stress) and a PIV set-up for measurement of unsteady flow profiles. This paper describes the test rig, the instrumentation layout and the test programme. Finally, some initial test results are presented and discussed

Differential cargo mobilisation within Weibel-Palade bodies after transient fusion with the plasma membrane.

Inflammatory chemokines can be selectively released from Weibel-Palade bodies (WPBs) during kiss-and-run exocytosis. Such selectivity may arise from molecular size filtering by the fusion pore, however differential intra-WPB cargo re-mobilisation following fusion-induced structural changes within the WPB may also contribute to this process. To determine whether WPB cargo molecules are differentially re-mobilised, we applied FRAP to residual post-fusion WPB structures formed after transient exocytosis in which some or all of the fluorescent cargo was retained. Transient fusion resulted in WPB collapse from a rod to a spheroid shape accompanied by substantial swelling (>2 times by surface area) and membrane mixing between the WPB and plasma membranes. Post-fusion WPBs supported cumulative WPB exocytosis. To quantify diffusion inside rounded organelles we developed a method of FRAP analysis based on image moments. FRAP analysis showed that von Willebrand factor-EGFP (VWF-EGFP) and the VWF-propolypeptide-EGFP (Pro-EGFP) were immobile in post-fusion WPBs. Because Eotaxin-3-EGFP and ssEGFP (small soluble cargo proteins) were largely depleted from post-fusion WPBs, we studied these molecules in cells preincubated in the weak base NH4Cl which caused WPB alkalinisation and rounding similar to that produced by plasma membrane fusion. In these cells we found a dramatic increase in mobilities of Eotaxin-3-EGFP and ssEGFP that exceeded the resolution of our method (∼ 2.4 µm2/s mean). In contrast, the membrane mobilities of EGFP-CD63 and EGFP-Rab27A in post-fusion WPBs were unchanged, while P-selectin-EGFP acquired mobility. Our data suggest that selective re-mobilisation of chemokines during transient fusion contributes to selective chemokine secretion during transient WPB exocytosis. Selective secretion provides a mechanism to regulate intravascular inflammatory processes with reduced risk of thrombosis

Psychotic Alzheimer\u27s disease is associated with gender-specific tau phosphorylation abnormalities

Converging evidence suggests that psychotic Alzheimer\u27s disease (AD + P) is associated with an acceleration of frontal degeneration, with tau pathology playing a primary role. Previous histopathologic and biomarker studies have specifically implicated tau pathology in this condition. To precisely quantify tau abnormalities in the frontal cortex in AD + P, we used a sensitive biochemical assay of total tau and 4 epitopes of phospho-tau relevant in AD pathology in a postmortem sample of AD + P and AD - P. Samples of superior frontal gyrus from 26 AD subjects without psychosis and 45 AD + P subjects with psychosis were analyzed. Results of enzyme-linked immunosorbent assay demonstrate that AD + P females, but not males, had significantly higher levels of phosphorylated tau in the frontal cortex. In males, but not females, AD + P was associated with the presence of alpha-synuclein pathology. These results support a gender dissociation of pathology in AD + P. The design of future studies aimed at the elucidation of cognitive and/or functional outcomes; regional brain metabolic deficits; or genetic correlates of AD + P should take gender into consideration. (C) 2014 Elsevier Inc. All rights reserved

Field experiments and meta-analysis reveal wetland vegetation as a crucial element in the coastal protection paradigm

Increasing rates of sea-level rise and wave action threaten coastal populations. Defense of shorelines by protection and restoration of wetlands has been invoked as a win-win strategy for humans and nature, yet evidence from field experiments supporting the wetland protection function is uncommon, as is the understanding of its context dependency. Here we provide evidence from field manipulations showing that the loss of wetland vegetation, regardless of disturbance size, increases the rate of erosion on wave-stressed shorelines. Vegetation removal (simulated disturbance) along the edge of salt marshes reveals that loss of wetland plants elevates the rate of lateral erosion and that extensive root systems, rather than aboveground biomass, are primarily responsible for protection against edge erosion in marshes. Meta-analysis further shows that disturbances that generate plant dieoff on salt marsh edges generally hasten edge erosion in coastal marshes and that the erosion protection function of wetlands relates more to lateral than vertical edge-erosional processes and is positively correlated with the amount of below-ground plant biomass lost. Collectively, our findings substantiate a coastal protection paradigm that incorporates preservation of shoreline vegetation, illuminate key context dependencies in this theory, and highlight local disturbances (e.g., oil spills) that kill wetland plants as agents that can accelerate coastal erosion

Fast flowing populations are not well mixed

In evolutionary dynamics, well-mixed populations are almost always associated with all-to-all interactions; mathematical models are based on complete graphs. In most cases, these models do not predict fixation probabilities in groups of individuals mixed by flows. We propose an analytical description in the fast-flow limit. This approach is valid for processes with global and local selection, and accurately predicts the suppression of selection as competition becomes more local. It provides a modelling tool for biological or social systems with individuals in motion.Comment: 19 pages, 8 figure

Investigating and learning lessons from early experiences of implementing ePrescribing systems into NHS hospitals:a questionnaire study

Background: ePrescribing systems have significant potential to improve the safety and efficiency of healthcare, but they need to be carefully selected and implemented to maximise benefits. Implementations in English hospitals are in the early stages and there is a lack of standards guiding the procurement, functional specifications, and expected benefits. We sought to provide an updated overview of the current picture in relation to implementation of ePrescribing systems, explore existing strategies, and identify early lessons learned.Methods: a descriptive questionnaire-based study, which included closed and free text questions and involved both quantitative and qualitative analysis of the data generated.Results: we obtained responses from 85 of 108 NHS staff (78.7% response rate). At least 6% (n = 10) of the 168 English NHS Trusts have already implemented ePrescribing systems, 2% (n = 4) have no plans of implementing, and 34% (n = 55) are planning to implement with intended rapid implementation timelines driven by high expectations surrounding improved safety and efficiency of care. The majority are unclear as to which system to choose, but integration with existing systems and sophisticated decision support functionality are important decisive factors. Participants highlighted the need for increased guidance in relation to implementation strategy, system choice and standards, as well as the need for top-level management support to adequately resource the project. Although some early benefits were reported by hospitals that had already implemented, the hoped for benefits relating to improved efficiency and cost-savings remain elusive due to a lack of system maturity.Conclusions: whilst few have begun implementation, there is considerable interest in ePrescribing systems with ambitious timelines amongst those hospitals that are planning implementations. In order to ensure maximum chances of realising benefits, there is a need for increased guidance in relation to implementation strategy, system choice and standards, as well as increased financial resources to fund local activitie