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Polarized resonant soft x-ray scattering (RSoXS) can leverage contrast between domains in mass, chemical bonds, and chain orientation to characterize polymer thin films. Although mass and chemical contrast can be predicted from the absorption spectra, the origins of orientational contrast are not fully understood. For example, in the case where one domain is crystalline, it is not obvious how the total crystallinity will affect the anisotropy. Using a simple calculation, we predict polarized RSoXS of model structures and compare with experiment. Through experiments and simulations, we demonstrate that scattering anisotropy is not monotonically related to local order but instead peaks when 50% of domains have aligned chains, i.e., when the sample is 50% crystalline.
This study examined (1) the association of dietary energy density from solid (EDS) and solid plus liquids (EDSL) with adiposity and cardiometabolic risk factors (CRF) in children with overweight and obesity, (2) the effect of under-reporting on the mentioned associations and (3) whether the association between ED and body composition and CRF is influenced by levels of physical activity. In a cross-sectional design, 208 overweight and obese children (8–12-year-old; 111 boys) completed two non-consecutive 24 h recalls. ED was calculated using two different approaches: EDS and EDSL. Under-reporters were determined with the Goldberg method. Body composition, anthropometry and fasting blood sample measurements were performed. Moderate to vigorous physical activity (MVPA) was registered with accelerometers (7-d-register). Linear regressions were performed to evaluate the association of ED with the previously mentioned variables. Neither EDS nor EDSL were associated with body composition or CRF. However, when under-reporters were excluded, EDS was positively associated with BMI (P=0·019), body fat percentage (P=0·005), abdominal fat (P=0·008) and fat mass index (P=0·018), while EDSL was positively associated with body fat percentage (P=0·008) and fat mass index (P=0·026). When stratifying the group according to physical activity recommendations, the aforementioned associations were only maintained for non-compliers. Cluster analysis showed that the low-ED and high-MVPA group presented the healthiest profile for all adiposity and CRF. These findings could partly explain inconsistencies in literature, as we found that different ED calculations entail distinct results. Physical activity levels and excluding under-reporters greatly influence the associations between ED and adiposity in children with overweight and obesity.
We investigated the distribution of comorbidities among adult tuberculosis (TB) patients in Chiapas, the poorest Mexican state, with a high presence of indigenous population, and a corridor for migrants from Latin America. Secondary analysis on 5508 new adult TB patients diagnosed between 2010 and 2014 revealed that the most prevalent comorbidities were diabetes mellitus (DM; 19.1%) and undernutrition (14.4%). The prevalence of DM in these TB patients was significantly higher among middle aged (41–64 years) compared with older adults (⩾65 years) (38.6% vs. 23.2%; P < 0.0001). The prevalence of undernutrition was lower among those with DM, and higher in communities with high indigenous presence. Immigrants only comprised 2% of all TB cases, but were more likely to have unfavourable TB treatment outcomes (treatment failure, death and default) when compared with those born in Chiapas (29.5% vs. 11.1%; P < 0.05). Unfavourable TB outcomes were also more prevalent among the TB patients with undernutrition, HIV or older age, but not DM (P < 0.05). Our study in Chiapas illustrates the challenges of other regions worldwide where social (e.g. indigenous origin, poverty, migration) and host factors (DM, undernutrition, HIV, older age) are associated with TB. Further understanding of these critical factors will guide local policy makers and health providers to improve TB management.
Resonant soft x-ray scattering (RSoXS) leverages chemical specificity to characterize thin films but is limited near the nitrogen edge. The challenge is that commercially available x-ray transparent substrates are composed of Si3N4 and thereby absorb incident x-rays and generate incoherent fluorescence. To overcome this challenge, we designed and fabricated Al2O3 free-standing films for use as RSoXS windows. Al2O3 films offer higher x-ray transmittance and minimal fluorescence near the nitrogen edge. As an example, Al2O3 windows allow for nitrogen RSoXS of conjugated block copolymer thin films that reveal domain spacings, which are not apparent with commercially available Si3N4 substrates.
Fe is an essential nutrient for many bacteria, and Fe supplementation has been reported to affect the composition of the gut microbiota in both Fe-deficient and Fe-replete individuals outside pregnancy. This study examined whether the dose of Fe in pregnancy multivitamin supplements affects the overall composition of the gut microbiota in overweight and obese pregnant women in early pregnancy. Women participating in the SPRING study with a faecal sample obtained at 16 weeks’ gestation were included in this substudy. For each subject, the brand of multivitamin used was recorded. Faecal microbiome composition was assessed by 16S rRNA sequencing and analysed with the QIIME software suite. Dietary intake of Fe was assessed using a FFQ at 16 weeks’ gestation. Women were grouped as receiving low (<60 mg/d, n 94) or high (≥60 mg/d; n 65) Fe supplementation. The median supplementary Fe intake in the low group was 10 (interquartile range (IQR) 5–10) v. 60 (IQR 60–60) mg/d in the high group (P<0·001). Dietary Fe intake did not differ between the groups (10·0 (IQR 7·4–13·3) v. 9·8 (IQR 8·2–13·2) mg/d). Fe supplementation did not significantly affect the composition of the faecal microbiome at any taxonomic level. Network analysis showed that the gut microbiota in the low Fe supplementation group had a higher predominance of SCFA producers. Pregnancy multivitamin Fe content has a minor effect on the overall composition of the gut microbiota of overweight and obese pregnant women at 16 weeks’ gestation.
The SPICA mid- and far-infrared telescope will address fundamental issues in our understanding of star formation and ISM physics in galaxies. A particular hallmark of SPICA is the outstanding sensitivity enabled by the cold telescope, optimised detectors, and wide instantaneous bandwidth throughout the mid- and far-infrared. The spectroscopic, imaging, and polarimetric observations that SPICA will be able to collect will help in clarifying the complex physical mechanisms which underlie the baryon cycle of galaxies. In particular, (i) the access to a large suite of atomic and ionic fine-structure lines for large samples of galaxies will shed light on the origin of the observed spread in star-formation rates within and between galaxies, (ii) observations of HD rotational lines (out to ~10 Mpc) and fine structure lines such as [C ii] 158 μm (out to ~100 Mpc) will clarify the main reservoirs of interstellar matter in galaxies, including phases where CO does not emit, (iii) far-infrared spectroscopy of dust and ice features will address uncertainties in the mass and composition of dust in galaxies, and the contributions of supernovae to the interstellar dust budget will be quantified by photometry and monitoring of supernova remnants in nearby galaxies, (iv) observations of far-infrared cooling lines such as [O i] 63 μm from star-forming molecular clouds in our Galaxy will evaluate the importance of shocks to dissipate turbulent energy. The paper concludes with requirements for the telescope and instruments, and recommendations for the observing strategy.
We describe the investigation of two temporally coincident illness clusters involving salmonella and Staphylococcus aureus in two states. Cases were defined as gastrointestinal illness following two meal events. Investigators interviewed ill persons. Stool, food and environmental samples underwent pathogen testing. Alabama: Eighty cases were identified. Median time from meal to illness was 5·8 h. Salmonella Heidelberg was identified from 27 of 28 stool specimens tested, and coagulase-positive S. aureus was isolated from three of 16 ill persons. Environmental investigation indicated that food handling deficiencies occurred. Colorado: Seven cases were identified. Median time from meal to illness was 4·5 h. Five persons were hospitalised, four of whom were admitted to the intensive care unit. Salmonella Heidelberg was identified in six of seven stool specimens and coagulase-positive S. aureus in three of six tested. No single food item was implicated in either outbreak. These two outbreaks were linked to infection with Salmonella Heidelberg, but additional factors, such as dual aetiology that included S. aureus or the dose of salmonella ingested may have contributed to the short incubation periods and high illness severity. The outbreaks underscore the importance of measures to prevent foodborne illness through appropriate washing, handling, preparation and storage of food.
Insect fauna biodiversity in natural protected areas has not been thoroughly studied. Therefore, the aim of this work was to assess whether and how vegetation types, land management and seasonality influence the diversity of Ichneumonidae (Hymenoptera) in the Ría Lagartos Biosphere Reserve (Mexico). A sampling programme was conducted using Malaise traps from 2008 to 2009 in three vegetation types, each with two conservation zones (core and buffer zones). Three seasons were considered: rainy, dry and north-winds (isolated storms from November to February). A total of 336 species were identified. Rarefaction and Generalized Linear Model indicated higher species richness and abundance, respectively, in the buffer zone of the dry forest; possible explanations for this finding include the intermediate disturbance hypothesis, wherein diversity can be higher in sites where disturbance is not very frequent or very intense, and the ‘enemies hypothesis’, wherein structural complexity and high plant diversity favour increased predators or, in this case, parasitoids. Diversity was higher during the rainy season, which may have been due to the higher availability of resources. Vegetation and management had a positive impact on the Coc (attack cocoons and pupae) and Myc (attack concealed larvae living in the fruiting bodies of mushrooms) parasitoid guilds. Members of the Coc guild are generalist parasitoids, which may be favoured in complex vegetation with a high richness of potential hosts and non-hosts. The Myc guild requires certain environmental conditions that promote fungal growth, such as humidity, that is absent in the other vegetation types of savannah and coastal dune scrubland.
We present polarimetric observations of the 4 ground-state transitions of OH, toward a sample of maser-emitting planetary nebulae (PNe) using the Australia Telescope Compact Array. This sample includes confirmed OH-emitting PNe, confirmed and candidate H2O-maser-emitting PNe. Polarimetric observations provide information related to the magnetic field of these sources. Maser-emitting PNe are very young PNe and magnetic fields are a key ingredient in the early evolution and shaping process of PNe. Our preliminary results suggest that magnetic field strengths may change very rapidly in young PNe.
The aim of this work is to calibrate and validate an empirical approach to predict the date of occurrence of the grapevine phenology (budburst, flowering and veraison) temporally and spatially at the within-field scale. It is based on the collaboration between a classical model of phenology based on climate data and a spatial model calibrated with ancillary data of phenology observations. This approach was tested and validated on a field of cv Cabernet Sauvignon. Results showed that the spatial component improved the fit of the climatic model, allowing the generation of maps of the grapevine phenology with errors lower than 5 days of prediction. Spatio-temporal model errors were mainly associated with the temporal component of the model.
This paper proposes a methodology aiming at using historical yield data to improve yield sampling and yield estimation. The sampling method is based on a collaboration between historical data (at least three years) and yield measurements of the year performed on some sites within the field. It assumes a temporal stability of within field yield spatial patterns over the years. The first factor of a principal component analysis (PCA) is used to summarize the stable temporal patterns of within field yield data and it represents a large part of the variability of the different years assuming yield temporal stability and a high positive correlation between this factor and the yield. This main factor is then used to choose the best sites to sample (target sampling). Yield measurements are then used to calibrate a model that relates yield values to coordinates on the first factor of the PCA. This sampling method was tested on three vine fields (Vitis vinifera L.) in Chile and France with different varieties (Chardonnay, Cabernet Sauvignon and Syrah). For each of these fields, yield data of several years were available at the within field level. After temporal stability of yield patterns was verified for almost all the fields, the proposed sampling method was applied. Results were compared to those of a classical random sampling method showing that the use of historical yield data allows sampling sites selection to be optimized. Errors in yield estimations were reduced by more than 10% in all the cases, except when yield stable patterns are affected by specific events, i.e. early frost occurring on Chardonnay field.
Introduction: Most medically unfit drivers are not reported to licensing authorities. In BC, physicians are only obligated to report unfit drivers who continue to drive after being warned to stop. This study investigates barriers to and incentives for physician reporting of medically unfit drivers. Methods: We used an online survey to study physician-reported barriers to reporting medically unfit drivers and their idea of incentives that would improve reporting. Email invitations to participate in the survey were sent to all physicians in BC through DoctorsofBC and to all emergency physicians (EPs) in the UBC Department of Emergency Medicine. Results: We received responses from 242 physicians (47% EPs, 40% GPs, 13% others). The most common barrier to reporting was not knowing which unfit drivers continue to drive (79% of respondents). Other barriers included lack of time (51%), lack of knowledge of the process, guidelines, or legal requirement for reporting (51%, 50%, 45% respectively), fearing loss of rapport with patients (48%), pressure from patients not to report (34%), lack of remuneration (27%), and pressure from family members not to report (25%).EPs were significantly less likely than other physicians to cite loss of rapport, pressure from patients, or pressure from family as barriers, but more likely to cite not being aware of drivers who continue to drive after being warned, lack of knowledge (regarding legal requirements to report, guidelines for determining fitness, and the reporting process), and lack of time. Factors that would increase reporting unfit drivers included better understanding of criteria for fitness to drive (70%), more information regarding how to report (67%), more information on when to report (65%), and compensation (43%).Free text comments from respondents identified other barriers/incentives. Reporting might be simplified by telephone hotlines or allowing physician designates to report. Physicians feared legal liability and suggested the need for better medico-legal protection. Loss of patient rapport might be minimized by public education. Failure of response from licensing authorities to a report (long wait times, lack of feedback to physician) was seen as a barrier to reporting. Conclusion: We identified barriers to physician reporting of medically unfit drivers and incentives that might increase reporting. This information could inform programs aiming to improve reporting of unfit drivers.
Introduction: Medical conditions that impair perception, cognition or motor skills may make people unfit to drive. Reporting unfit drivers to licensing authorities is seen by many as a public health obligation. This study investigates physician knowledge, attitudes and practice around the management of medically unfit drivers. Methods: We used an online survey to explore physician knowledge of fitness to drive issues and their attitudes and practice with regard to counselling and reporting unfit drivers. Email invitations to participate in the survey were sent to all physicians in BC through DoctorsofBC and to all emergency physicians (EPs) in the UBC Department of Emergency Medicine. Results: We received responses from 242 physicians (47% EPs, 40% GPs, 13% others). The majority (78%) reported little/no knowledge on determining driver fitness and 94% had little/no training around guidelines, reporting, and laws involving fitness to drive. Most (88%) agreed that physicians should be obligated to advise medically unfit patients not to drive, and 74% reported that they often warn patients not to drive. The majority of physicians also chart their opinion of patients’ fitness to drive (67% do so more than twice per year). Most respondents (70%) indicated that it is “always appropriate” to report definitely unfit drivers whereas only 25% indicated that it is “always appropriate” to report potentially unfit drivers. However, in practice physicians see far more unfit drivers than they report to licensing authority: 67% of physicians encounter definitely unfit drivers more than twice per year but only 19% report definitely unfit drivers more than twice per year and 34% never report definitely unfit drivers. Compared to other physicians, EPs reported less knowledge and training about criteria for determining fitness to drive, were more likely to feel that reporting unfit drivers was not their responsibility, and were less likely to report unfit drivers to licensing authorities. Conclusion: Our findings indicate a need for more education and information resources to help physicians, particularly EPs, identify and manage medically unfit drivers. Although most physicians warn unfit drivers not to drive and document this in medical records, many medically unfit drivers are not reported to licensing authorities, a potential public health problem that should be further investigated.
Supernova (SN) 1987A has provided a unique opportunity to study how SN ejecta evolve in 30 years time scale. We report our ALMA spectral observations of SN 1987A, taken in 2014, 2015 and 2016, with detections of CO, 28SiO, HCO+ and SO, with weaker lines of 29SiO.
We find a dip in the SiO line profiles, suggesting that the ejecta morphology is likely elongated. The difference of the CO and SiO line profiles is consistent with hydrodynamic simulations, which show that Rayleigh-Taylor instabilities causes mixing of gas, with heavier elements much more disturbed, making more elongated structure.
Using 28SiO and its isotopologues, Si isotope ratios were estimated for the first time in SN 1987A. The estimated ratios appear to be consistent with theoretical predictions of inefficient formation of neutron rich atoms at lower metallicity, such as observed in the Large Magellanic Cloud (about half a solar metallicity).
The deduced large HCO+ mass and small SiS mass, which are inconsistent to the predictions of chemical model, might be explained by some mixing of elements immediately after the explosion. The mixing might have made some hydrogen from the envelope to sink into carbon and oxygen-rich zone during early days after the explosion, enabling the formation of a substantial mass of HCO+. Oxygen atoms may penetrate into silicon and sulphur zone, suppressing formation of SiS.
Our ALMA observations open up a new window to investigate chemistry, dynamics and explosive-nucleosynthesis in supernovae.
Commercial aluminum alloys corresponding to Al-Cu-Si family are commonly used in casting and molding process because their high castability. The main characteristics of these alloys are the excellent weight/strength relation in conjunction with wear and corrosion resistance. Additionally, the mechanical properties of these alloys could be enhanced by heat treatment.
In Al A319 alloys, Cu and Mg are the main responsible to increase the mechanical properties after T6 heat treatment due to the precipitation of Al2Cu and Mg2Si and Al2CuMg phase . Combined effects of Ni and Cu improve strength and hardness at relatively elevated temperature , Due to the low solubility of Ni in Al (0.04%), it has been reported the formation of FeAl9FeNi-type intermetallic, which is not totally dissolved with the typical solution treatments used in aluminum alloys . Hayajneh et al., found that increasing amounts of intermetallic compounds Al3Ni, Al3(CuNi)2 and Al7Cu4Ni in Al-Cu alloy, the hardness increase .
The effect of Ni addition and solution treatment time on the microstructure and hardness of the Al A319 alloy are studied by Vickers microhardness (VHN), Rockwell B hardness (HRB), X Ray Diffraction (XRD), Optical Microscopy (OM), Scanning Electron Microscopy (SEM).