Insight into the impact of atomic- and nano-scale indium distributions on the optical properties of InGaN/GaN quantum well structures grown on m -plane freestanding GaN substrates

We investigate the atomic scale structure of m-plane InGaN quantum wells grown on bulk m-plane GaN templates and reveal that as the indium content increases there is an increased tendency for non-random clustering of indium atoms to occur. Based on the atom probe tomography data used to reveal this clustering, we develop a k.p model that takes these features into account, and links the observed nanostructure to the optical properties of the quantum wells. The calculations show that electrons and holes tend to co-localise at indium clusters. The transition energies between the electron and hole states are strongly affected by the shape and size of the clusters. Hence, clustering contributes to the very large line widths observed in the experimental low temperature photoluminescence spectra. Also, the emission from m-plane InGaN quantum wells is strongly linearly polarised. Clustering does not alter the theoretically predicted polarisation properties, even when the shape of the cluster is strongly asymmetric. Overall, however, we show that the presence of clustering does impact the optical properties, illustrating the importance of careful characterisation of the nanoscale structure of m-plane InGaN quantum wells and that atom probe tomography is a useful and important tool to address this problem

Microencapsulated foods as a functional delivery vehicle for omega-3 fatty acids: a pilot study

It is well established that the ingestion of the omega-3 (N3) fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) positively benefit a variety of health indices. Despite these benefits the actual intake of fish derived N3 is relatively small in the United States. The primary aim of our study was to examine a technology capable of delivering omega-3 fatty acids in common foods via microencapsulation (MicroN3) in young, healthy, active participants who are at low risk for cardiovascular disease. Accordingly, we randomized 20 participants (25.4 ± 6.2 y; 73.4 ± 5.1 kg) to receive the double blind delivery of a placebo-matched breakfast meal (~2093 kJ) containing MicroN3 (450–550 mg EPA/DHA) during a 2-week pilot trial. Overall, we observed no differences in overall dietary macronutrient intake other than the N3 delivery during our treatment regimen. Post-test ANOVA analysis showed a significant elevation in mean (SE) plasma DHA (91.18 ± 9.3 vs. 125.58 ± 11.3 umol/L; P < 0.05) and a reduction in triacylglycerols (89.89 ± 12.8 vs. 80.78 ± 10.4 mg/dL; P < 0.05) accompanying the MicroN3 treatment that was significantly different from placebo (P < 0.05). In post study interviews, participants reported that the ingested food was well-tolerated, contained no fish taste, odor or gastrointestinal distress accompanying treatment. The use of MicroN3 foods provides a novel delivery system for the delivery of essential fatty acids. Our study demonstrates that MicroN3 foods promote the absorption of essential N3, demonstrate bioactivity within 2 weeks of ingestion and are well tolerated in young, active participants who are at low risk for cardiovascular disease

Evolutionary conservation of lampbrush-like loops in drosophilids

<p>Abstract</p> <p>Background</p> <p>Loopin-1 is an abundant, male germ line specific protein of <it>Drosophila melanogaster</it>. The polyclonal antibody T53-F1 specifically recognizes Loopin-1 and enables its visualization on the Y-chromosome lampbrush-like loop named kl-3 during primary spermatocyte development, as well as on sperm tails. In order to test lampbrush-like loop evolutionary conservation, extensive phase-contrast microscopy and immunostaining with T53-F1 antibody was performed in other drosophilids scattered along their genealogical tree.</p> <p>Results</p> <p>In the male germ line of all species tested there are cells showing giant nuclei and intranuclear structures similar to those of <it>Drosophila melanogaster </it>primary spermatocytes. Moreover, the antibody T53-F1 recognizes intranuclear structures in primary spermatocytes of all drosophilids analyzed. Interestingly, the extent and conformation of the staining pattern is species-specific. In addition, the intense staining of sperm tails in all species suggests that the terminal localization of Loopin-1 and its orthologues is conserved. A comparison of these cytological data and the data coming from the literature about sperm length, amount of sperm tail entering the egg during fertilization, shape and extent of both loops and primary spermatocyte nuclei, seems to exclude direct relationships among these parameters.</p> <p>Conclusion</p> <p>Taken together, the data reported strongly suggest that lampbrush-like loops are a conserved feature of primary spermatocyte nuclei in many, if not all, drosophilids. Moreover, the conserved pattern of the T53-F1 immunostaining indicates that a Loopin-1-like protein is present in all the species analyzed, whose localization on lampbrush-like loops and sperm tails during spermatogenesis is evolutionary conserved.</p

Dorsal hippocampal involvement in conditioned-response timing and maintenance of temporal information in the absence of the CS

Involvement of the dorsal hippocampus (DHPC) in conditioned-response timing and maintaining temporal information across time gaps was examined in an appetitive Pavlovian conditioning task, in which rats with sham and DHPC lesions were first conditioned to a 15-s visual cue. After acquisition, the subjects received a series of non-reinforced test trials, on which the visual cue was extended (45 s) and gaps of different duration, 0.5, 2.5, and 7.5 s, interrupted the early portion of the cue. Dorsal hippocampal-lesioned subjects underestimated the target duration of 15 s and showed broader response distributions than the control subjects on the no-gap trials in the first few blocks of test, but the accuracy and precision of their timing reached the level of that of the control subjects by the last block. On the gap trials, the DHPC-lesioned subjects showed greater rightward shifts in response distributions than the control subjects. We discussed these lesion effects in terms of temporal versus non-temporal processing (response inhibition, generalisation decrement, and inhibitory conditioning)

Nevirapine Resistance and Breast-Milk HIV Transmission: Effects of Single and Extended-Dose Nevirapine Prophylaxis in Subtype C HIV-Infected Infants

Daily nevirapine (NVP) prophylaxis to HIV-exposed infants significantly reduces breast-milk HIV transmission. We assessed NVP-resistance in Indian infants enrolled in the "six-week extended-dose nevirapine" (SWEN) trial who received single-dose NVP (SD-NVP) or SWEN for prevention of breast-milk HIV transmission but who also acquired subtype C HIV infection during the first year of life.Standard population sequencing and cloning for viral subpopulations present at > or =5% frequency were used to determine HIV genotypes from 94% of the 79 infected Indian infants studied. Timing of infection was defined based on when an infant's blood sample first tested positive for HIV DNA. SWEN-exposed infants diagnosed with HIV by six weeks of age had a significantly higher prevalence of NVP-resistance than those who received SD-NVP, by both standard population sequencing (92% of 12 vs. 38% of 29; p = 0.002) and low frequency clonal analysis (92% of 12 vs. 59% of 29; p = 0.06). Likelihood of infection with NVP-resistant HIV through breast-milk among infants infected after age six weeks was substantial, but prevalence of NVP-resistance did not differ among SWEN or SD-NVP exposed infants by standard population sequencing (15% of 13 vs. 15% of 20; p = 1.00) and clonal analysis (31% of 13 vs. 40% of 20; p = 0.72). Types of NVP-resistance mutations and patterns of persistence at one year of age were similar between the two groups. NVP-resistance mutations did differ by timing of HIV infection; the Y181C variant was predominant among infants diagnosed in the first six weeks of life, compared to Y188C/H during late breast-milk transmission.Use of SWEN to prevent breast-milk HIV transmission carries a high likelihood of resistance if infection occurs in the first six weeks of life. Moreover, there was a continued risk of transmission of NVP-resistant HIV through breastfeeding during the first year of life, but did not differ between SD-NVP and SWEN groups. As with SD-NVP, the value of preventing HIV infection in a large number of infants should be considered alongside the high risk of resistance associated with extended NVP prophylaxis.ClinicalTrials.gov NCT00061321

Race/Ethnicity and gender differences in health intentions and behaviors regarding exercise and diet for adults with type 2 diabetes: A cross-sectional analysis

<p>Abstract</p> <p>Background</p> <p>Self-management is the cornerstone of diabetes control and prevention of complications; however, it is undetermined whether differences in intention to adopt healthy lifestyles and actual healthy behavior exist across race/ethnic groups. This study evaluated the differences across racial-ethnic groups in self-reported medical advice received and health intentions and behaviors among adults with type 2 diabetes mellitus.</p> <p>Methods</p> <p>A cross-sectional analysis of the 2007 SHIELD US survey ascertained self-reported health intentions and behaviors for regular exercise, diet, and weight management among Non-Hispanic Caucasian (n = 2526), Non-Hispanic African-American (n = 706), and Hispanic (n = 179) respondents with type 2 diabetes.</p> <p>Results</p> <p>A similar proportion of respondents from each race-gender group (43%-56%) reported receiving healthcare advice to increase their exercise (P = 0.32). Significantly more minorities reported an intention to follow the exercise recommendation compared with Non-Hispanic Caucasians (P = 0.03). More Non-Hispanic African-American (29%) and Hispanic (27%) men reported exercising regularly compared with other race-gender groups (P = 0.02). Significantly more Non-Hispanic Caucasian women (74%) and Hispanic women (79%) reported trying to lose weight compared with other groups (P < 0.0001).</p> <p>Conclusions</p> <p>Differences in health intentions and healthy behaviors were noted across race-gender groups. More Non-Hispanic African-American men reported an intention to follow advice on exercising and self-report of exercising regularly was also higher compared with other race-gender groups. More Hispanic men reported high physical activity levels than other groups. Despite an increased willingness to follow healthcare recommendations for diet, >50% of respondents were obese among all race-gender groups.</p

A search for quantitative trait loci controlling within-individual variation of physical activity traits in mice

<p>Abstract</p> <p>Background</p> <p>In recent years it has become increasingly apparent that physical inactivity can predispose individuals to a host of health problems. While many studies have analyzed the effect of various environmental factors on activity, we know much less about the genetic control of physical activity. Some studies in mice have discovered quantitative trait loci (QTL) influencing various physical activity traits, but mostly have analyzed inter-individual variation rather than variation in activity within individuals over time. We conducted a genome scan to identify QTLs controlling the distance, duration, and time run by mice over seven consecutive three-day intervals in an F₂population created by crossing two inbred strains (C57L/J and C3H/HeJ) that differed widely (average of nearly 300%) in their activity levels. Our objectives were (a) to see if we would find QTLs not originally discovered in a previous investigation that assessed these traits over the entire 21-day period and (b) to see if some of these QTLs discovered might affect the activity traits only in the early or in the late time intervals.</p> <p>Results</p> <p>This analysis uncovered 39 different QTLs, over half of which were new. Some QTLs affected the activity traits only in the early time intervals and typically exhibited significant dominance effects whereas others affected activity only in the later age intervals and exhibited less dominance. We also analyzed the regression slopes of the activity traits over the intervals, and found several QTLs affecting these traits that generally mapped to unique genomic locations.</p> <p>Conclusions</p> <p>It was concluded that the genetic architecture of physical activity in mice is much more complicated than has previously been recognized, and may change considerably depending on the age at which various activity measures are assessed.</p

Two cold inducible genes encoding lipid transfer protein LTP4 from barley show differential responses to bacterial pathogens

The barley genesHvLtp4.2 andHvLtp4.3 both encode the lipid transfer protein LTP4 and are less than 1 kb apart in tail-to-tail orientation. They differ in their non-coding regions from each other and from the gene corresponding to a previously reportedLtp4 cDNA (nowLtp4.1). Southern blot analysis indicated the existence of three or moreLtp4 genes per haploid genome and showed considerable polymorphism among barley cultivars. We have investigated the transient expression of genesHvLtp4.2 andHvLtp4.3 following transformation by particle bombardment, using promoter fusions to the-glucuronidase reporter sequence. In leaves, activities of the two promoters were of the same order as those of the sucrose synthase (Ss1) and cauliflower mosaic virus 35S promoters used as controls. Their expression patterns were similar, except thatLtp4.2 was more active thanLtp4.3 in endosperm, andLtp4.3 was active in roots, whileLtp4.2 was not. The promoters of both genes were induced by low temperature, both in winter and spring barley cultivars. Northern blot analysis, using theLtp4-specific probe, indicated thatXanthomonas campestris pv.translucens induced an increase over basal levels ofLtp4 mRNA, whilePseudomonas syringae pv.japonica caused a decrease. TheLtp4.3-Gus promoter fusion also responded in opposite ways to these two compatible bacterial pathogens, whereas theLtp4.2-Gus construction did not respond to infectio

Recent progress in understanding and projecting regional and global mean sea-level change

Considerable progress has been made in understanding the present and future regional and global sea level in the 2 years since the publication of the Fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change. Here, we evaluate how the new results affect the AR5’s assessment of (i) historical sea level rise, including attribution of that rise and implications for the sea level budget, (ii) projections of the components and of total global mean sea level (GMSL), and (iii) projections of regional variability and emergence of the anthropogenic signal. In each of these cases, new work largely provides additional evidence in support of the AR5 assessment, providing greater confidence in those findings. Recent analyses confirm the twentieth century sea level rise, with some analyses showing a slightly smaller rate before 1990 and some a slightly larger value than reported in the AR5. There is now more evidence of an acceleration in the rate of rise. Ongoing ocean heat uptake and associated thermal expansion have continued since 2000, and are consistent with ocean thermal expansion reported in the AR5. A significant amount of heat is being stored deeper in the water column, with a larger rate of heat uptake since 2000 compared to the previous decades and with the largest storage in the Southern Ocean. The first formal detection studies for ocean thermal expansion and glacier mass loss since the AR5 have confirmed the AR5 finding of a significant anthropogenic contribution to sea level rise over the last 50 years. New projections of glacier loss from two regions suggest smaller contributions to GMSL rise from these regions than in studies assessed by the AR5; additional regional studies are required to further assess whether there are broader implications of these results. Mass loss from the Greenland Ice Sheet, primarily as a result of increased surface melting, and from the Antarctic Ice Sheet, primarily as a result of increased ice discharge, has accelerated. The largest estimates of acceleration in mass loss from the two ice sheets for 2003–2013 equal or exceed the acceleration of GMSL rise calculated from the satellite altimeter sea level record over the longer period of 1993–2014. However, when increased mass gain in land water storage and parts of East Antarctica, and decreased mass loss from glaciers in Alaska and some other regions are taken into account, the net acceleration in the ocean mass gain is consistent with the satellite altimeter record. New studies suggest that a marine ice sheet instability (MISI) may have been initiated in parts of the West Antarctic Ice Sheet (WAIS), but that it will affect only a limited number of ice streams in the twenty-first century. New projections of mass loss from the Greenland and Antarctic Ice Sheets by 2100, including a contribution from parts of WAIS undergoing unstable retreat, suggest a contribution that falls largely within the likely range (i.e., two thirds probability) of the AR5. These new results increase confidence in the AR5 likely range, indicating that there is a greater probability that sea level rise by 2100 will lie in this range with a corresponding decrease in the likelihood of an additional contribution of several tens of centimeters above the likely range. In view of the comparatively limited state of knowledge and understanding of rapid ice sheet dynamics, we continue to think that it is not yet possible to make reliable quantitative estimates of future GMSL rise outside the likely range. Projections of twenty-first century GMSL rise published since the AR5 depend on results from expert elicitation, but we have low confidence in conclusions based on these approaches. New work on regional projections and emergence of the anthropogenic signal suggests that the two commonly predicted features of future regional sea level change (the increasing tilt across the Antarctic Circumpolar Current and the dipole in the North Atlantic) are related to regional changes in wind stress and surface heat flux. Moreover, it is expected that sea level change in response to anthropogenic forcing, particularly in regions of relatively low unforced variability such as the low-latitude Atlantic, will be detectable over most of the ocean by 2040. The east-west contrast of sea level trends in the Pacific observed since the early 1990s cannot be satisfactorily accounted for by climate models, nor yet definitively attributed either to unforced variability or forced climate change

Design and Deploying Tools to ‘Actively Engaging Nature’: The My Naturewatch Project as an Agent for Engagement

‘Shifting Baseline Syndrome’ is highly apparent in the context of generational shifts in work and life patterns that reduce interaction with and knowledge of the natural world, and therefore expectations of it. This is exacerbated by changes in the natural world itself due to climate change, biodiversity decline and a range of anthropogenic factors. Distributed and accessible technologies, and grass roots approaches provide fresh opportunities for interactions, which enable active engagement in ecological scenarios. The My NatureWatch project uses digital devices to collect visual content about UK wildlife, promoting ‘active engagements with nature’. The project embodies Inclusive Design in the Digital Age, as the activity; engages a wide demographic community, can be used by all, provided user led agency and produced methodological design lessons. The article frames My Naturewatch as an agent for active designed engagements with nature. The research objective is to comprehend ‘how to design tools for positive nature engagement’ holding value for; (1) academic communities as validated methodologies (2) the public through access to enabling technologies, content and knowledge (3) industry in the form of new; experiences, engagements and commerce. The approach is specifically designed to yield insights from a multitude of engagements, through the deployment of accessible, lowcost products. Project reporting documents the benefits, pitfalls and opportunities in the aforementioned engagement uncovered through design-led approaches. Insights are gathered from public/community facing workshops, wildlife experts, ecologists, economists, educators and wildlife NGO’s. The engagement methodologies are compared highlighting which initiative yielded ‘Active Engagement with Nature’