Atmospheric drying and soil drying: Differential effects on grass community composition.

Global surface temperatures are projected to increase in the future; this will modify regional precipitation regimes and increase global atmospheric drying. Despite many drought studies examining the consequences of reduced precipitation, there are few experimental studies exploring plant responses to atmospheric drying via relative humidity and vapor pressure deficit (VPD). We examined eight native California perennial grass species grown in pots in a greenhouse in Los Angeles, California for 34 weeks. All pots were well-watered for 21 weeks, at which point we reduced watering to zero and recorded daily growth and dormancy for 3 weeks. We used this information to better understand the drought tolerance of our species in a larger soil drying × atmospheric drying experiment. In this larger experiment, we grew all eight species together in outdoor mesocosms and measured changes in community composition after 4 years of growth. Soil drying in our small pot experiment mirrored compositional shifts in the larger experiment. Namely, our most drought-tolerant species in our pot experiment was Poa secunda, due to a summer dormancy strategy. Similarly, the grass community shifted toward P. secunda in the driest soils as P. secunda was mostly unaffected by either soil drying or atmospheric drying. We found that some species responded strongly to soil drying (Elymus glaucus, Festuca idahoensis, and Hordeum b. californicum), while others responded strongly to atmospheric drying (Bromus carinatus and Stipa cernua). As result, community composition shifted in different and interacting ways in response to soil drying, atmospheric drying, and their combination. Further study of community responses to increasing atmospheric aridity is an essential next step to predicting the future consequences of climate change.

Simulating atmospheric drought: Silica gel packets dehumidify mesocosm microclimates.

1. As global temperatures rise, droughts are becoming more frequent and severe. To predict how drought might affect plant communities, ecologists have traditionally designed experiments with controlled watering regimes and rainout shelters. Both treatments have proven effective for simulating soil drought. However, neither are designed to directly modify atmospheric drought. 2. Here, we detail the efficacy of a silica gel atmospheric drought treatment in outdoor mesocosms with and without a cooccurring soil drought treatment. At California State University, Los Angeles, we monitored relative humidity (RH), temperature, and vapor pressure deficit (VPD) every 10 minutes for five months in a bare-ground experiment featuring mesocosms treated with soil drought (reduced watering) and/or atmospheric drought (silica packets suspended 12 cm above soil). 3. We found that silica packets dehumidified these microclimates most effectively (-5% RH) when combined with reduced soil water, regardless of the ambient humidity levels of the surrounding air. Further, packets increased microclimate VPD most effectively (+0.4 kPa) when combined with reduced soil water and ambient air temperatures above 20°C. Finally, packets simulated atmospheric drought most consistently when replaced within three days of deployment. 4. Our results demonstrate the use of silica packets as effective dehumidification agents in outdoor drought experiments. We emphasize that incorporating atmospheric drought in existing soil drought experiments can improve our understandings of the ecological impacts of drought.

Comparison of static and dynamic in vitro digestibility and bioaccessibility of palm-based emulsions and correlation to a human study: effects of triacylglycerol crystallinity.

The static and dynamic TIM-1 in vitro digestibility of similarly sized Span 60 o/w emulsions containing either liquid palm olein droplets (PO) or palm stearin (PS) droplets tempered to contain different levels of crystallinity (i.e., PS-SE (maximum), PS-SE-INT (intermediate), and PS-LE (undercooled)) were explored. Static in vitro digestion experiments included particle size analysis, and emulsion digestibility and bioaccessibility were compared between the static and dynamic models, respectively. ß-carotene (BC, 0.1 wt%) was also incorporated in the emulsions to determine the influence of triacylglycerol (TAG) crystallinity on BC bioaccessibility and stability during storage under accelerated lighting conditions. TAG crystallinity altered the colloidal fat crystal network properties and ultimately impacted lipid digestion, attenuating early static in vitro lipolysis for the PS emulsions compared to the PO emulsion. This correlated well with TIM-1 bioaccessibility trends and with results from our results of a previous human study wherein the rise in postprandial TAG was delayed when healthy men consumed PS-SE versus PS-LE. The presence of crystalline TAG modestly accelerated BC degradation, and did not improve preservation nor alter BC in vitro bioaccessibility.

C-terminal citrullinated peptide alters antigen-specific APC:T cell interactions leading to breach of immune tolerance.

In rheumatoid arthritis, the emergence of anti-citrullinated autoimmunity is associated with HLA-antigen-T cell receptor complexes. The precise mechanisms underpinning this breach of tolerance are not well understood. Porphyromonas gingivalis expresses an enzyme capable of non-endogenous C-terminal citrullination with potential to generate citrullinated autoantigens. Here we document how C-terminal citrullination of ovalbumin peptide323-339 alters the interaction between antigen-presenting cells and OTII T cells to induce functional changes in responding T cells. These data reveal that C-terminal citrullination is sufficient to breach T cell peripheral tolerance in vivo and reveal the potential of C-terminal citrullination to lower the threshold for T cell activation. Finally, we demonstrate a role for the IL-2/STAT5/CD25 signalling axis in breach of tolerance. Together, our data identify a tractable mechanism and targetable pathways underpinning breach of tolerance in rheumatoid arthritis and provide new conceptual insight into the origins of anti-citrullinated autoimmunity.

Electron beam evaporation of superconductor-ferromagnet heterostructures.

We report on the electronic and magnetic properties of superconductor-ferromagnet heterostructures fabricated by electron beam evaporation on to unheated thermally oxidised Si substrates. Polycrystalline Nb thin films (5 to 50 nm thick) were shown to possess reliably high superconducting critical temperatures ([Formula: see text]), which correlate well with the residual resistivity ratio (RRR) of the film. These properties improved during ex-situ annealing, resulting in [Formula: see text] and [Formula: see text]RRR increases of up 2.2 K ([Formula: see text] 40% of the pre-annealed [Formula: see text]) and 0.8 ([Formula: see text] 60% of the pre-annealed RRR) respectively. Nb/Pt/Co/Pt heterostructures showed substantial perpendicular anisotropy in the ultrathin limit (≤ 2.5 nm), even in the extreme limit of Pt(0.8 nm)/Co(1 nm)/Pt(0.6 nm). These results point to the use of electron beam evaporation as route to line-of-sight deposited, low-thickness, high quality Nb-based superspintronic multilayers.

Lipid crystallinity of oil-in-water emulsions alters in vitro.

10 wt% oil-in-water emulsions with varied palm olein and stearin PO:PS ratios stabilized with 0.8 wt% Tween80 and tempered to obtain partially crystalline (CR) droplets (cooled from 80 to 4 °C and held overnight to induce nucleation/crystallization) or undercooled liquid (UC) droplets (cooled from 80 °C to 37 °C) produced emulsions with constant droplet size and polymorphism. However, zeta-potential decreased in undercooled emulsions due to crystallization/orientation of interfacial Tween, increasing alignment and ultimately a greater dipole moment. Significant differences in overall bioaccessibility between PO and PS present for the CR (PO bioaccessible fraction was 91%, whereas PS was 60%) and UC emulsions (PO and PS bioaccessibility were 96% and 77%).When only the solid fat content differs, and all other physical attributes remain constant, lipid digestibility decreases with increasing solid fat content; these findings, along with others, can be employed during food formulation and design more healthful foods.

Sous Vide Cook Temperature Alters the Physical Structure and Lipid Bioaccessibility of Beef Longissimus Muscle in TIM-1.

Changes in the physical states, induced with different sous vide cooking temperatures, significantly (P < 0.05) altered lipid bioaccessibility measured in the TNO-simulated gastrointestinal tract model-1 of AAA boneless beef striploin, containing the longissimus lumborum muscle. The denaturation of actin significantly correlates with the total cumulative free fatty acid (FFA) bioaccessibility, whereby the striploin cooked to 60 °C presents the maximum lipid bioaccessibility (15.8 ± 1.0%), rate constant (ka) for FFA hydrolysis (0.087 ± 0.003 min-1), and greatest actin denaturation enthalpy (-0.57 ± 0.06 ΔH). Thus, thermal treatments above 60 °C significantly decrease the kinetics of lipolysis (70 °C = 0.042 ± 0.002 min-1 and 80 °C = 0.047 ± 0.002 min-1) and the resultant total lipid bioaccessibility (70 °C = 8.6 ± 0.7 and 80 °C = 8.3 ± 0.5%). This research highlights the potential to manipulate the physical food structure to alter digestion kinetics, supporting the need to understand supramolecular structures in food and their nutritional outcomes.

Stress gradients and biodiversity: monoculture vulnerability drives stronger biodiversity effects during drought years.

Climate change will increase the likelihood and severity of droughts into the future. Although diversity may buffer plant communities against the negative effects of drought, the mechanisms underlying this pattern remain unclear. Higher-diversity plant communities may have a higher likelihood of including more drought-resistant species that can compensate for drought-sensitive species ("insurance effects"). Alternatively, higher-diversity communities may alter environmental conditions and improve performance of even drought-sensitive species. Here we planted nonleguminous forbs and grasses into monocultures and four- and eight-species mixtures, and measured species and plot productivity every year from 2000 to 2010. We found that six of our eight species were suppressed when growing in monoculture during dry years. These same species were unaffected by drought when growing in higher-diversity mixtures. Because of this poor performance in monoculture (not insurance effects), the biodiversity productivity relationship was strongest during the driest years. If biodiversity ameliorates hot/dry conditions and therefore improves performance of drought-sensitive species during periods of low rainfall, this may mean biodiversity can be used as a tool to protect individual species from drought conditions.

Peptide gels of fully-defined composition and mechanics for probing cell-cell and cell-matrix interactions in vitro.

Current materials used for in vitro 3D cell culture are often limited by their poor similarity to human tissue, batch-to-batch variability and complexity of composition and manufacture. Here, we present a "blank slate" culture environment based on a self-assembling peptide gel free from matrix motifs. The gel can be customised by incorporating matrix components selected to match the target tissue, with independent control of mechanical properties. Therefore the matrix components are restricted to those specifically added, or those synthesised by encapsulated cells. The flexible 3D culture platform provides full control over biochemical and physical properties, allowing the impact of biochemical composition and tissue mechanics to be separately evaluated in vitro. Here, we demonstrate that the peptide gels support the growth of a range of cells including human induced pluripotent stem cells and human cancer cell lines. Furthermore, we present proof-of-concept that the peptide gels can be used to build disease-relevant models. Controlling the peptide gelator concentration allows peptide gel stiffness to be matched to normal breast (<1 kPa) or breast tumour tissue (>1 kPa), with higher stiffness favouring the viability of breast cancer cells over normal breast cells. In parallel, the peptide gels may be modified with matrix components relevant to human breast, such as collagen I and hyaluronan. The choice and concentration of these additions affect the size, shape and organisation of breast epithelial cell structures formed in co-culture with fibroblasts. This system therefore provides a means of unravelling the individual influences of matrix, mechanical properties and cell-cell interactions in cancer and other diseases.

Designing a facile low cost synthesis strategy for the Na-V-S-O systems, NaV(SO4)2, Na3V(SO4)3 and Na2VO(SO4)2.

Alkali metal transition metal sulfates have attracted considerable interest as potential electrodes for Na ion battery materials. While there has been significant research on Fe based systems, research on V based systems has been lacking, apart from a recent report on Na2VO(SO4)2. This can be related to the complex synthetic routes previously reported to make sodium vanadium sulfate systems. In this paper, we report a simple route towards the synthesis of three such sodium vanadium sulfate systems, NaV(SO4)2, Na2VO(SO4)2, and Na3V(SO4)3. We analyse the resulting products through X-ray diffraction and Raman spectroscopy to highlight the formation of high quality samples via this simple solution route, with subsequent low temperature (<400 °C) heat treatment. This facile new route will allow these materials to be considered for future applications rather than as simply chemical curiosities.

Effect of milk protein intake and casein-to-whey ratio in breakfast meals on postprandial glucose, satiety ratings, and subsequent meal intake.

Whey and casein proteins differentially affect postprandial blood glucose and satiety mechanisms, with relevance for type 2 diabetes and obesity. Therefore, the purpose of this work was to investigate the effect of the casein-to-whey protein ratio and total protein concentration of milks consumed with cereal on postprandial blood glucose, appetite ratings, and subsequent food intake in a randomized, controlled, double-blinded study with healthy young adults (n = 32, 23.4 ± 3.1 yr, body mass index = 22.2 ± 2.5 kg/m2). Fasted participants consumed milk (250 mL) with either 80:20 or 40:60 (modified) casein-to-whey protein ratios at commercially normal (3.1%, wt) or high protein (9.3%, wt) concentration, or control (water with whey permeate), each along with 2 servings of oat-based breakfast cereal. Blood glucose concentrations were determined from finger prick blood samples and appetite was assessed using visual analog scales. Participants consumed a measured ad libitum pizza lunch at 120 min and blood glucose determination and appetite assessment continued following the lunch meal (140-200 min) to observe the second meal effect. Pre-lunch (0-120 min) incremental area under the curve (iAUC) and mean change from baseline blood glucose were reduced with consumption of all milk treatments relative to control. However, we found no differences between all treatments on pre-lunch appetite change from baseline and total area under the curve (tAUC) or lunch meal food intake. In terms of protein concentration results, high protein (9.3%, wt) treatments contrasted to normal protein (3.1%, wt) treatments lowered blood glucose change from baseline and iAUC, and post-lunch appetite change from baseline and tAUC. Protein ratio showed a modest effect in that modified (40:60) protein ratio lowered pre-lunch blood glucose change from baseline but not iAUC, and normal (80:20) protein ratio lowered pre-lunch appetite change from baseline but not tAUC. Therefore, high-carbohydrate breakfast meals with increased protein concentration (9.3%, wt) could be a dietary strategy for the attenuation of blood glucose and improved satiety ratings after the second meal.

Influences on use of hand moisturizers in nurses.

Background: Nurses are at high risk of hand dermatitis. Regular hand moisturizing can prevent dermatitis, but nurses' use of hand moisturizers is suboptimal. Aims: To establish (i) what beliefs about hand dermatitis and hand moisturizer use are associated with hand moisturizer use by nurses at home and at work and (ii) if hand moisturizer use behaviours in nurses are associated with the prevalence of hand dermatitis. Methods: We used a questionnaire to investigate nurses' knowledge, beliefs and behaviours regarding hand dermatitis and use of hand moisturizers. Results: The response rate was 55/65 (85%). Forty-two (76%) participants agreed that applying hand moisturizers reduced the risk of dermatitis, and 53 (96%) agreed that dermatitis increased the risk of skin carrying pathogenic organisms. Frequent moisturizer application was associated with beliefs that it was part of the nurse's role to apply hand creams, a belief that they had had training in the use of moisturizers and believing that patients approved of them moisturizing their hands. Conclusions: Hand moisturizer use by nurses can be improved by enhancing their beliefs that it is part of their professional role to apply hand cream regularly.

Towards Improving the Transfer of Care of Kidney Transplant Recipients.

Kidney transplant recipients require specialized medical care and may be at risk for adverse health outcomes when their care is transferred. This document provides opinion-based recommendations to facilitate safe and efficient transfers of care for kidney transplant recipients including minimizing the risk of rejection, avoidance of medication errors, ensuring patient access to immunosuppressant medications, avoidance of lapses in health insurance coverage, and communication of risks of donor disease transmission. The document summarizes information to be included in a medical transfer document and includes suggestions to help the patient establish an optimal therapeutic relationship with their new transplant care team. The document is intended as a starting point towards standardization of transfers of care involving kidney transplant recipients.

Surface-enhanced Raman scattering measurement from a lipid bilayer encapsulating a single decahedral nanoparticle mediated by an optical trap.

We present a new technique for the study of model membranes on the length-scale of a single nano-sized liposome. Silver decahedral nanoparticles have been encapsulated by a model unilamellar lipid bilayer creating nano-sized lipid vesicles. The metal core has two roles (i) increasing the polarizability of vesicles, enabling a single vesicle to be isolated and confined in an optical trap, and (ii) enhancing Raman scattering from the bilayer, via the high surface-plasmon field at the sharp vertices of the decahedral particles. Combined this has allowed us to measure a Raman fingerprint from a single vesicle of 50 nm-diameter, containing just ∼104 lipid molecules in a bilayer membrane over a surface area of <0.01 µm2, equivalent to a volume of approximately 1 zepto-litre. Raman scattering is a weak and inefficient process and previous studies have required either a substantially larger bilayer area in order to obtain a detectable signal, or the tagging of lipid molecules with a chromophore to provide an indirect probe of the bilayer. Our approach is fully label-free and bio-compatible and, in the future, it will enable much more localized studies of the heterogeneous structure of lipid bilayers and of membrane-bound components than is currently possible.

Bladder and bowel continence in bilateral cerebral palsy: A population study.

INTRODUCTION: The attainment of continence is an important milestone in all children, including those with disability. OBJECTIVE: To describe the age of bladder and bowel continence in children with bilateral cerebral palsy (BCP), and the association with intellectual impairment (II) and severity of motor disability. PATIENTS AND METHODS: The parents of 346 children with BCP were interviewed as part of a population-based prospective study of the children at 3, 7, and 17 years of age. The age of bladder and bowel continence by day and night was ascertained and compared with controls from the Avon Longitudinal Study of Parents and Children (ALSPAC). RESULTS: The median age for daytime bladder and bowel continence in BCP children was 5.4 years compared with 2.4 years in the controls. At 13.8 years of age, 59.4% of BCP children and 99% of controls were continent by day. In BCP children, there was no difference between the attainment of daytime bladder and bowel control. Night-time bladder and bowel control was slower and less completely attained, with 50% of BCP children continent by the age of 11.8 years compared with 3 years in control children. At 13.8 years of age, 51.9% of BCP children compared with 99.4% of controls were continent for bowel and bladder at night. Gross Motor Functional Classification Score (GMFCS) and intellectual ability (IA) (II) were strongly associated with continence attainment (P < 0.0001), but gender was not. DISCUSSION: Delayed and less complete continence attainment was noted in other clinic series of children with cerebral palsy (including hemiplegics) and children with II. Severity of motor disability (GMFCS), and II impacted on other aspects of toilet training, such as: motivation, understanding, communication, and independence skills. The presence of neurogenic bladder and bowel dysfunction can occur in all levels of GMFCS. Thus, there are many reasons that can prevent continence attainment. CONCLUSIONS: Children with BCP achieved day and night-time bladder and bowel continence more slowly and less completely than controls, with 60.8% being continent by day and 54.6% by night at the age of 17 years. The majority of BCP children who were continent by day had achieved this by the age of 5.5 years (86%). At least 88% of BCP children with GMFCS I/II and normal, specific or mild learning impairment were continent for bladder and bowel by day and night. Expectations should be shared with parents, and failure to attain expected continence should be actively investigated.

Investigations of in vitro bioaccessibility from interesterified stearic and oleic acid-rich blends.

Interesterification was previously found to impact stearic acid absorption in a randomized cross-over study, when human volunteers consumed a 70 : 30 wt% high-oleic sunflower and canola stearin blend (NIE) compared to the same blend which had undergone either chemical (CIE) or enzymatic (EIE) interesterification. In this research, in vitro lipid digestion, bioaccessibility, and changes in undigested lipid composition and melting behavior of these same test fats were investigated using the dynamic, multi-compartmental TIM-1 digestion model and compared with the previous human study. Overall, TIM-1 bioaccessibility was higher with interesterification (p < 0.05). Oleic acid bioaccessibility was higher than stearic acid bioaccessibility for NIE, and vice versa for the interesterified blends (p < 0.05). Stearic acid was more concentrated in the undigested triacylglycerols (TAG) from NIE, corresponding to a relatively higher melting temperature of the undigested lipids. The results confirm the impact of TAG composition, fatty acid position and/or physical properties on lipid digestion. TIM-1 bioaccessibility was linearly correlated (R(2) = 0.8640) with postprandial serum TAG concentration in the human study. Therefore, the in vitro digestion model offered predictive insights related to the impacts of lipid interesterificaton on absorption.

Lamivudine compared with newer antivirals for prophylaxis of hepatitis B core antibody positive livers: a cost-effectiveness analysis.

There is concern over the development of de novo hepatitis B in patients receiving liver transplants from hepatitis B surface antigen negative, hepatitis B core antibody positive donors. Current practice is to place such patients on indefinite lamivudine prophylaxis; however, there is a small risk of breakthrough infection and newer antivirals for hepatitis B are available. The objective of this study was to determine the cost-effectiveness of lamivudine compared with the newer agents, tenofovir and entecavir, in the prophylaxis setting using a Markov model. Three strategies were examined which consisted of either lamivudine or entecavir monoprophylaxis with tenofovir add-on therapy after breakthrough or tenofovir monoprophylaxis with emtricitabine add-on therapy after breakthrough. In the base case scenario, lamivudine was the most cost-effective option at a threshold of $100 000 per quality-adjusted life-year and this remained robust despite parameter uncertainty. Tenofovir had an incremental cost-effectiveness ratio of $3 540 194.77 while other strategies were superior to entecavir therapy. Until drug costs decrease, lamivudine remains the most cost-effective option for hepatitis B prophylaxis in the liver transplant setting.