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Crystal structure and electronic structure of YMnO3 were investigated by X-ray diffraction and transmission electron microscopy related techniques. According to the density of states (DOS), the individual interband transitions to energy loss peaks in the low energy loss spectrum were assigned. The hybridization of O 2p with Mn 3d and Y 4d analyzed by the partial DOS was critical to the ferroelectric nature of YMnO3. From the simulation of the energy loss near-edge structure, the fine structure of O K-edge was in good agreement with the experimental spectrum. The valence state of Mn (+3) in YMnO3 was determined by a comparison between experiment and calculations.
Micronutrient supplementation is recommended in Ebola Virus Disease (EVD). However, there is limited data on its therapeutic impacts. This study evaluated the association between vitamin A supplementation and mortality outcomes in EVD patients.
This retrospective cohort study accrued patients with EVD admitted to five International Medical Corps run Ebola Treatment Units (ETU) in two countries from 2014-2015. Protocolized treatments with antimicrobials and micronutrients were used at all ETUs. However, due to resource limitations and care variations, only a subset of patients received vitamin A. Standardized data on demographics, clinical characteristics, malaria status, and Ebola virus RT-PCR cycle threshold (CT) values were collected. The outcome of interest was mortality compared between cases treated with 200,000 International Units of vitamin A on care days one and two and those not. Propensity scores (PS) based on the first 48-hours of care were derived using the covariates of age, duration of ETU function, malaria status, CT values, symptoms of confusion, hemorrhage, diarrhea, dysphagia, and dyspnea. Treated and non-treated cases were matched 1:1 based on nearest neighbors with replacement. Covariate balance met predefined thresholds. Mortality proportions between cases treated and untreated with vitamin A were compared using generalized estimating equations to calculate relative risks (RR) with associated 95% confidence intervals (CI).
There were 424 cases analyzed, with 330 (77.8%) being vitamin A-treated cases. The mean age was 30.5 years and 57.0% were female. The most common symptoms were diarrhea (86%), anorexia (81%), and vomiting (77%). Mortality proportions among cases untreated and treated with vitamin A were 71.9% and 55.0%, respectively. In a propensity-matched analysis, mortality was significantly lower among cases receiving vitamin A (RR = 0.77 95%; CI:0.59-0.99; p = 0.041).
Early vitamin A supplementation was associated with reduced mortality in EVD patients and should be provided routinely during future epidemics.
This study was designed to explore the association between undernutrition in the growth period and cardiovascular risk factors in a middle-aged Chinese population. A total of 1756 subjects, aged 45–60 years, were invited to participate in the Hefei Nutrition and Health Study and divided into three groups according to their self-reported animal food intake in the growth period. Group 1, Group 2 and Group 3 were defined as undernutrition, nutritional improvement and the good nutrition group, respectively. In the three groups, the subjects in Groups 1 and 2 had more oil and salt intake (P<0.001), and less eggs and milk intake (P<0.001), when compared with the subjects in Group 3. After adjusting for age, education, smoking status and other confounding factors, it was found that male participants who experienced nutritional improvement before age 18 had higher risk of hypertension [odds ratio (OR)=1.68; 95% confidence intervals (CI): 1.05, 2.69] than those with good nutrition, and female participants with undernutrition (OR=1.52; 95% CI: 1.01, 2.29) and nutritional improvement (OR=1.68; 95% CI: 1.04, 2.69) before age 18 had a higher risk of hypertension than those with good nutrition. For diabetes, obesity, hypercholesterolemia and hypertriglyceridemia, our results did not found difference among the three groups both in male and female. Our findings indicated that nutritional deficiency in childhood was associated with bad dietary behaviors and a significantly increased risk of hypertension in middle age. Therefore, early adequate nutrition is very important for the prevention of non-communicable diseases later.
The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
The icing wind tunnel can simulate the air flow at a high altitude; such an air flow contains supercooled droplets moving at certain velocities. An integrated experiment method was proposed, and it included the icing test and shear stress measurements in the simulated environment of the icing wind tunnel. The error caused by the change in experimental environments was completely eliminated with this novel method. Thus, there was no discrepancy between the real-time and experimental values of shear stress between the ice and substrate. The experiments of icing and shear stress measurements are carried out by varying the following parameters: icing temperature, mean volume diameter (MVD) of droplets, and surface roughness of the substrate. The results indicate that the shear stress between the ice and the substrate increases with the decrease in temperature provided the temperature is relatively high. When the MVD value is 22 μm, the liquid water content is about 1 g/m3 and surface roughness is 2 μm. Under these conditions, the shear stress reaches its maximum value at a temperature of –15°C. The shear stress is also affected by the MVD values of droplets, and the surface roughness of substrate.
Studies of schizophrenia at drug-naive state and on antipsychotic medication have reported a number of regions of gray-matter (GM) abnormalities but the reports have been inconsistent. The aim of this study was to conduct multimodal meta-analysis to compare the cross-sectional voxel-based morphometry studies of brain GM in antipsychotic-naive first-episode schizophrenia (AN-FES) and those with antipsychotic treatment within 1 year (AT-FES) to determine the similarities and differences in these groups. We conducted two separate meta-analyses containing 24 studies with a sample size of 801 patients and 957 healthy controls. A multimodal meta-analysis method was used to compare the findings between AN-FES and AT-FES. Meta-regression analyses were done to determine the influence of different variables including age, duration of illness, and positive and negative symptom scores. Finally, jack-knife analyses were done to test the robustness of the results. AN-FES and AT-FES showed common patterns of GM abnormalities in frontal (gyrus rectus), superior temporal, left hippocampal and insular cortex. GM in the left supramarginal gyrus and left middle temporal gyrus were found to be increased in AN-FES but decreased in AT-FES, whereas left median cingulate/paracingulate gyri and right hippocampus GM was decreased in AN-FES but increased in AT-FES. Findings suggest that both AN-FES and AT-FES share frontal, temporal and insular regions as common anatomical regions to be affected indicating these to be the primary regions of GM abnormalities in both groups.
In this work, we utilize a method based on Wang-Landau Monte Carlo sampling for studying the temperature effects of astrophysically relavant molecules. Anharmonic effects, e.g., resonances, overtones, and combination bands, are fully incoportated in this method. The calculated infrared (IR) spectra are consistent with the experimental data measured by National Institute of Standards and Technology (NIST).
Feeding a high concentrate (HC) diet is a widely used strategy for supporting high milk yields, yet it may cause certain metabolic disorders. This study aimed to investigate the changes in milk production and hepatic metabolism in goats fed different proportions of concentrate in the diet for 10 weeks. In total, 12 mid-lactating goats were randomly assigned to an HC diet (65% concentrate of dry matter, n=6) or a low concentrate (LC) diet (35% concentrate of dry matter, n=6). Compared with LC, HC goats produced greater amounts of volatile fatty acids and produced more milk and milk lactose, fat and protein (P<0.01). HC goats showed a greater concentration of ATP, NAD, plasma non-esterified fatty acids and hepatic triglycerides than LC goats (P<0.05). Real-time PCR results showed that messenger RNA (mRNA) expression of gluconeogenic genes, namely, glucose-6-phosphatase, pyruvate carboxylase and phosphoenolpyruvate carboxykinase were significantly up-regulated and accompanied greater gluconeogenic enzyme activities in the liver of HC goats. Moreover, the expression of hepatic lipogenic genes including sterol regulatory element-binding protein 1c, fatty acid synthase and diacylglycerol acyltransferase mRNA was also up-regulated by the HC diet (P<0.05). HC goats had greater hepatic phosphorylation of AMP-activated protein kinase than LC (P<0.05). Furthermore, histone-3-lysine-27-acetylation contributed to this elevation of gluconeogenic gene expression. These results indicate that lactating goats fed an HC diet for 10 weeks produced more milk, which was associated with up-regulated gene expression and enzyme activities involved in hepatic gluconeogenesis and lipogenesis.
Titanium oxide photoelectrodes have been used for water splitting for a few decades, but have low solar-to-hydrogen efficiencies. Perovskite halides (e.g., CH3NH3PbI3) have recently emerged as an efficient light absorber system. We try to combine the two materials to create new photoelectrodes to achieve a higher efficiency for hydrogen production. The photoelectrodes are investigated for water-splitting hydrogen production under Xe light irradiation by photoelectrochemical (PEC) reaction. Since perovskite halides are favorable light harvesters under UV and visible light irradiation, the composite films of titania and perovskite halide would achieve efficient water splitting. The hydrogen production rate using the composite films is higher than that using anatase TiO2 electrode. However, the composite films are not stable in water under light irradiation and the perovskite halide gradually decomposes into lead halide.
The Australian Centre for Advanced Photovoltaics (ACAP) co-ordinates the activities of the six Australian research institutions and a group of industrial partners in the Australia-US Institute for Advanced Photovoltaics (AUSIAPV) to develop the next generations of photovoltaic device technology and to provide a pipeline of opportunities for performance increase and cost reduction. AUSIAPV links ACAP with US-based partners. These national and international research collaborations provide a pathway for highly visible, structured photovoltaic research collaboration between Australian and US researchers, institutes and agencies with significant joint programs based on the clear synergies between the participating organizations. The research program is organized in five collaborative Program Packages (PPs). PP1 deals with silicon wafer-based cells, focusing on three main areas: cells from solar grade silicon, rear contact and silicon-based tandem cells. PP2 involves research into a range of organic solar cells, organic/inorganic hybrid cells, "earth abundant" thin-film materials and "third generation" approaches. PP3 is concerned with optics and characterization. PP4 will deliver a substantiated methodology for assessing manufacturing costs of the different technologies and PP5 involves education, training and outreach. The main research topics, results and plans for the future are presented.
The impact of nanostructured broadband antireflection (AR) coatings on solar panel performance has been projected for a broad range of panel tilt angles at various locations. AR coated films have been integrated on test panels and the short-circuit current has been measured for the entire range of panel tilts. The integration of the AR coatings resulted in an increase in short-circuit current of the panels by eliminating front sheet reflection loss for a broad spectrum of light and wide angle of light incidence. The short-circuit current enhancement is 5% for normal light incidence and approximately 20% for off-angle light incidence. The National Renewable Energy Laboratory (NREL) System Advisor Model (SAM) predicts that this AR coating can yield at least 6.5% improvement in solar panel annual power output. The greatest enhancement, approximately 14%, is predicted for vertical panels. The AR coating’s contributions to vertical mount panels and building-integrated solar panels are significant. This nanostructured broadband AR coating thus has the potential to lower the cost per watt of photovoltaic solar energy.
Long term stability of mixed perovskite compounds is one of the important concerns for prolonged viability and economical use of perovskite based solar cells. Degradation in perovskite films mainly occurs due to exposure to moisture. Hence, a controlled atmospheric condition and lower humidity is preferred for device fabrication and use. Many different strategies such as use of thin and wide band gap semiconductor layer, improvement in pour filling of metal oxide film, and utilization of AgTFSI have been attempted to improve device stability. However, for long term durability, there is an urgent need to increase stability of parent perovskite layer, apart from use of protective layers. In this study we examined water resistant additive, structural modifications, and stoichiometric modification for enhanced film durability. These strategies and preliminary results are discussed in this report.
Flexible copper indium gallium diselenide (CIGS) solar cells on lightweight substrates can deliver high specific powers. Flexible lightweight CIGS solar cells are also primary candidates for building-integrated panels. In all applications, CIGS cells can greatly benefit from the application of broadband and wide-angle AR coating technology. The AR coatings can significantly improve the transmittance of light over the entire CIGS absorption band spectrum. Increased short-circuit current has been observed after integrating AR coated films onto baseline solar panels. NREL’s System Advisor Model (SAM) has predicted up to 14% higher annual power output on AR integrated vertical or building-integrated panels. The combination of lightweight flexible substrates and advanced device designs employing nanostructured optical coatings together have the potential to achieve flexible CIGS modules with enhanced efficiencies and specific power.
Some studies have found a significant relationship between birth weight (BW) and the risk of coronary heart disease (CHD) in adulthood, but results were inconsistent. The purpose of this study was to characterize the association between BW and the risk of CHD in adults. Among 144 papers detected by our search, 27 papers provided data on the relationship between BW and CHD, of which 23 papers considered BW as a continuous variable, and 14 articles considered BW as a categorical variable for this meta-analysis. Based on 23 papers, the mean weighted estimate for the association between BW and the combined outcome of non-fatal and fatal CHD was 0.83 [95% confidence interval (CI), 0.80–0.86] per kilogram of BW (P<0.0001). Low birth weight (LBW<2500 g) was associated with increased risk of CHD [odds ratio (OR), 1.19; 95% confidence interval (CI), 1.11–1.27] compared with subjects with BW⩾2500 g. LBW, as compared with normal BW (2500–4000 g), was associated with increased risk of CHD (OR, 1.16; 95% CI, 1.08–1.25). High birth weight (HBW⩾4000 g) was associated with decreased risk of CHD (OR, 0.89; 95% CI, 0.81–0.98) compared with subjects with BW<4000 g. In addition, there was an indication (not quite significant) that HBW was associated with a lower risk of CHD (OR, 0.89; 95% CI, 0.79–1.01), as compared with normal BW. No significant evidence of publication bias was present. These results suggest that LBW is significantly associated with increased risk of CHD and a 1 kg higher BW is associated with a 10–20% lower risk of CHD.
Silylated kaolinites were synthesized at 80°C without the use of inert gas protection. The method presented started with mechanical grinding of kaolinite, followed by grafting with 3- aminopropyltriethoxysilane (APTES). The mechanical grinding treatment destroyed the ordered sheets of kaolinite, formed fine fragments and generated broken bonds (undercoordinated metal ions). These broken bonds served as new sites for the condensation with APTES. Fourier transform infrared spectroscopy (FTIR) confirmed the existence of −CH2 from APTES. 29Si cross-polarization magic-angle spinning nuclear magnetic resonance spectroscopy (29Si CP/MAS NMR) showed that the principal bonding mechanism between APTES and kaolinite fitted a tridentate silylation model (T3) with a chemical shift at −66.7 ppm. The silane loadings of the silylated samples were estimated from the mass loss obtained by TG-DTG curves. The results showed that the 6-hour ground kaolinite could be grafted with the most APTES (7.0%) using cyclohexane as solvent. The loaded amount of APTES in the silylated samples obtained in different solvents decreased in the order as: nonpolar solvent > polar solvent with low dielectric constant (toluene) > polar solvent with high dielectric constant (ethanol).
Despite substantial research, uncertainty remains about the clinical and etiological heterogeneity of major depression (MD). Can meaningful and valid subtypes be identified and would they be stable cross-culturally?
Symptoms at their lifetime worst depressive episode were assessed at structured psychiatric interview in 6008 women of Han Chinese descent, age ⩾30 years, with recurrent DSM-IV MD. Latent class analysis (LCA) was performed in Mplus.
Using the nine DSM-IV MD symptomatic A criteria, the 14 disaggregated DSM-IV criteria and all independently assessed depressive symptoms (n = 27), the best LCA model identified respectively three, four and six classes. A severe and non-suicidal class was seen in all solutions, as was a mild/moderate subtype. An atypical class emerged once bidirectional neurovegetative symptoms were included. The non-suicidal class demonstrated low levels of worthlessness/guilt and hopelessness. Patterns of co-morbidity, family history, personality, environmental precipitants, recurrence and body mass index (BMI) differed meaningfully across subtypes, with the atypical class standing out as particularly distinct.
MD is a clinically complex syndrome with several detectable subtypes with distinct clinical and demographic correlates. Three subtypes were most consistently identified in our analyses: severe, atypical and non-suicidal. Severe and atypical MD have been identified in multiple prior studies in samples of European ethnicity. Our non-suicidal subtype, with low levels of guilt and hopelessness, may represent a pathoplastic variant reflecting Chinese cultural influences.