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The Square Kilometre Array (SKA) is a planned large radio interferometer designed to operate over a wide range of frequencies, and with an order of magnitude greater sensitivity and survey speed than any current radio telescope. The SKA will address many important topics in astronomy, ranging from planet formation to distant galaxies. However, in this work, we consider the perspective of the SKA as a facility for studying physics. We review four areas in which the SKA is expected to make major contributions to our understanding of fundamental physics: cosmic dawn and reionisation; gravity and gravitational radiation; cosmology and dark energy; and dark matter and astroparticle physics. These discussions demonstrate that the SKA will be a spectacular physics machine, which will provide many new breakthroughs and novel insights on matter, energy, and spacetime.
We describe the motivation and design details of the ‘Phase II’ upgrade of the Murchison Widefield Array radio telescope. The expansion doubles to 256 the number of antenna tiles deployed in the array. The new antenna tiles enhance the capabilities of the Murchison Widefield Array in several key science areas. Seventy-two of the new tiles are deployed in a regular configuration near the existing array core. These new tiles enhance the surface brightness sensitivity of the array and will improve the ability of the Murchison Widefield Array to estimate the slope of the Epoch of Reionisation power spectrum by a factor of ∼3.5. The remaining 56 tiles are deployed on long baselines, doubling the maximum baseline of the array and improving the array u, v coverage. The improved imaging capabilities will provide an order of magnitude improvement in the noise floor of Murchison Widefield Array continuum images. The upgrade retains all of the features that have underpinned the Murchison Widefield Array’s success (large field of view, snapshot image quality, and pointing agility) and boosts the scientific potential with enhanced imaging capabilities and by enabling new calibration strategies.
Gut symbionts can augment resistance to pathogens by stimulating host-immune responses, competing for space and nutrients, or producing antimicrobial metabolites. Gut microbiota of social bees, which pollinate many crops and wildflowers, protect hosts against diverse infections and might counteract pathogen-related bee declines. Bumble bee gut microbiota, and specifically abundance of Lactobacillus ‘Firm-5’ bacteria, can enhance resistance to the trypanosomatid parasite Crithidia bombi. However, the mechanism underlying this effect remains unknown. We hypothesized that the Firm-5 bacterium Lactobacillus bombicola, which produces lactic acid, inhibits C. bombi via pH-mediated effects. Consistent with our hypothesis, L. bombicola spent medium inhibited C. bombi growth via reduction in pH that was both necessary and sufficient for inhibition. Inhibition of all parasite strains occurred within the pH range documented in honey bees, though sensitivity to acidity varied among strains. Spent medium was slightly more potent than HCl, d- and l-lactic acids for a given pH, suggesting that other metabolites also contribute to inhibition. Results implicate symbiont-mediated reduction in gut pH as a key determinant of trypanosomatid infection in bees. Future investigation into in vivo effects of gut microbiota on pH and infection intensity would test the relevance of these findings for bees threatened by trypanosomatids.
Current policy emphasises the importance of ‘living well’ with dementia, but there has been no comprehensive synthesis of the factors related to quality of life (QoL), subjective well-being or life satisfaction in people with dementia. We examined the available evidence in a systematic review and meta-analysis. We searched electronic databases until 7 January 2016 for observational studies investigating factors associated with QoL, well-being and life satisfaction in people with dementia. Articles had to provide quantitative data and include ⩾75% people with dementia of any type or severity. We included 198 QoL studies taken from 272 articles in the meta-analysis. The analysis focused on 43 factors with sufficient data, relating to 37639 people with dementia. Generally, these factors were significantly associated with QoL, but effect sizes were often small (0.1–0.29) or negligible (<0.09). Factors reflecting relationships, social engagement and functional ability were associated with better QoL. Factors indicative of poorer physical and mental health (including depression and other neuropsychiatric symptoms) and poorer carer well-being were associated with poorer QoL. Longitudinal evidence about predictors of QoL was limited. There was a considerable between-study heterogeneity. The pattern of numerous predominantly small associations with QoL suggests a need to reconsider approaches to understanding and assessing living well with dementia.
We report seven cases of probable endotoxin poisoning linked to contaminated compounded glutathione. Five of the cases were using the infusions for treatment of Lyme disease highlighting the risks of using compounded sterile preparations for unapproved indications, especially if the quality of source products cannot be assured.
Innovative evidence-based interventions are needed to equip research mentors with skills to address cultural diversity within research mentoring relationships. A pilot study assessed initial outcomes of a culturally tailored effort to create and disseminate a novel intervention titled Culturally Aware Mentoring (CAM) for research mentors.
Intervention development resulted in 4 products: a 6 hour CAM training curriculum, a facilitator guide, an online pretraining module, and metrics to evaluate the effectiveness of CAM training.
Participants were 64 research mentors from 3 US research-intensive universities. Quantitative pretraining and posttraining evaluation survey data were collected.
Participants found high value and satisfaction with the CAM training, reported gains in personal cultural awareness and cultural skills, and increased intentions and confidence to address cultural diversity in their mentoring.
Study findings indicate that the CAM training holds promise to build research mentors’ capacity and confidence to engage directly with racial/ethnic topics in research mentoring relationships.
Recently, organic farming systems have attracted the attention of consumers because of their low environmental impact. Organic agriculture is a valid alternative to conventional farming and ancient wheat, such as KAMUT® khorasan wheat (T. turgidum ssp. turanicum), has emerged as an industry leader for its nutritional and functional properties (anti-inflammatory, antioxidant and prebiotic).
The aim of the present study was to evaluate environmental effects on the quality of KAMUT® khorasan grains harvested in the last two decades (1989–2012) on one farm in Montana (USA), through the evaluation of phytochemical accumulation. Results revealed high variability in the amounts of macronutrients and nutraceuticals. In particular, from 1989 to 2012, there was a decreasing trend in starch content (ranging from 70·87 to 50·54/100 g) and amylose (from 41·48 to 31·46% of total starch) with a slight increase of insoluble dietary fibre (from 12·14 to 17·75/100 g). The soluble dietary fibre content varied among the years of cultivation even if the general trend remained constant (4·57–2·82/100 g). High variability of total polyphenols content was observed with the free soluble fraction present at lower levels than bound polyphenols (BP). Moreover, an inverse correlation between free and BP was observed. The results obtained in the present study show that the influence of environmental conditions plays a fundamental role in the accumulation of primary and secondary metabolites in wheat kernels and strongly modulate the nutritional and nutraceutical value of flour.
Mars landed and orbiter missions have instrumentation capable of detecting oxychlorine phases (e.g. perchlorate, chlorate) on the surface. Perchlorate (~0.6 wt%) was first detected by the Wet Chemistry Laboratory in the surface material at the Phoenix Mars Landing site. Subsequent analyses by the Thermal Evolved Gas Analyser aboard the same lander detected an oxygen release (~465°C) consistent with the thermal decomposition of perchlorate. Recent thermal analysis by the Mars Science Laboratory's Sample Analysis at Mars instrument has also indicated the presence of oxychlorine phases (up to 1.2 wt%) in Gale Crater materials. Despite being at detectable concentrations, the Chemistry and Mineralogy (CheMin) X-ray diffractometer has not detected oxychlorine phases. This suggests that Gale Crater oxychlorine may exist as poorly crystalline phases or that perchlorate/chlorate mixtures exist, so that individual oxychlorine concentrations are below CheMin detection limits (~1 wt%). Although not initially designed to detect oxychlorine phases, reinterpretation of Viking Gas Chromatography/Mass Spectrometer data also suggest that oxychlorine phases are present in the Viking surface materials. Remote near-infrared spectral analyses by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) instrument indicate that at least some martian recurring slope lineae (RSL) have spectral signatures consistent with the presence of hydrated perchlorates or chlorates during the seasons when RSL are most extensive. Despite the thermal emission spectrometer, Thermal Emission Imaging System, Observatoire pour la Minéralogie, l'Eau, les Glaces et l'Activité and CRISM detection of hundreds of anhydrous chloride (~10–25 vol%) deposits, expected associated oxychlorine phases (>5–10 vol%) have not been detected. Total Cl and oxychlorine data sets from the Phoenix Lander and the Mars Science Laboratory missions could be used to develop oxychlorine versus total Cl correlations, which may constrain oxychlorine concentrations at other locations on Mars by using total Cl determined by other missions (e.g. Viking, Pathfinder, MER and Odyssey). Development of microfluidic or ‘lab-on-a-chip’ instrumentation has the potential to be the next generation analytical capability used to identify and quantify individual oxychlorine species on future landed robotic missions to Mars.
Parasite dynamics can be mediated by host behaviours such as sociality, and seasonal changes in aggregation may influence risk of parasite exposure. We used little brown bats (Myotis lucifugus) captured during the autumn mating/swarming period to test the hypothesis that seasonal and demographic-based variation in sociality affect ectoparasitism. We predicted that ectoparasitism would: (1) be higher for adult females and young of the year (YOY) than adult males because of female coloniality; (2) increase for adult males throughout swarming because of increasing contact with females; (3) decrease for adult females and YOY throughout swarming because of reduced coloniality and transmission of individual ectoparasites to males; (4) be similar for male and female YOY because vertical transmission from adult females should be similar. Ectoparasitism was lowest for adult males and increased for males during swarming, but some effects of demographic were unexpected. Contrary to our prediction, ectoparasitism increased for adult females throughout swarming and YOY males also hosted fewer ectoparasites compared with adult and YOY females. Interestingly, females in the best body condition had the highest parasite loads. Our results suggest that host energetic constraints associated with future reproduction affect pre-hibernation parasite dynamics in bats.
Provision of non-pharmacological interventions is a common policy objective for people with dementia, and support groups are an increasingly common intervention. However, there have been few attempts to synthesize evidence on the effectiveness of support groups for people with dementia. This review investigated the outcomes of support groups for people with dementia, explored participant characteristics and reviewed group formats.
A systematic review was undertaken and a narrative synthesis of data from 29 papers (reporting on 26 groups and a survey of a range of groups) was conducted.
Support groups seem acceptable to people with dementia. Qualitative studies report subjective benefits for participants but there is limited evidence of positive outcomes based on quantitative data. Samples have tended to be homogenous and this may limit the generalizability of findings.
Although qualitative studies will remain important in this area, further mixed-methods randomized controlled trials (RCTs)or comparison group studies with longer follow-up periods are needed to strengthen the evidence base.
Customary institutions are used successfully in some Ugandan communities, but not in others. There may be several explanations for this. First, the nature of social institutions clearly changes over time; it is likely that the utility of traditional practices has also changed accordingly. Secondly, the presence of protracted civil conflict in various parts of the country has altered the manner in which people are able to live and deal with conflict. Thirdly, the scope of conflict may have caused traditions to become dislocated or modified beyond any recognizable or useful form, which may have caused traditional mechanisms to become less useful or entirely obsolete. Fourthly, societies in Uganda are stratified very differently; this organization has had a major role to play in whether and how such mechanisms are used. Fifthly, the homogeneity of the population could be a key factor in whether, and whose, “traditions” are used in a given community.