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In a survey of 471 patients, we collected self-reported weight and height data and asked about self-perceptions of provider support toward weight loss and other weight management concerns. Multivariable analysis found that respondents with higher body mass index (BMI) were more likely to report that a physician had told them that they were overweight (OR=3.49, 95% CI 2.06–5.89, P<0.001). However, this conversation was less likely to change their personal view of their weight (OR=0.62 per 5 kg/m2, 95% CI 0.45–0.86, P=0.004), or motivate them to lose weight (OR=0.67 per 5 kg/m2, 95% CI 0.50–0.91, P=0.009). Higher BMI was associated with higher weight-loss goals (P<0.001), while anticipated time to achieve those goals was increased (P<0.001). Physician involvement in weight management was important, but the patients’ needs and experiences differed by BMI. Approaches to addressing barriers and identifying resources for weight management should be tailored to individuals by considering BMI.
Several authors claimed that expression of suicidal ideation is one of the most important predictors of completed suicide. However, the strength of the association between suicidal ideation and subsequent completed suicide has not been firmly established in different populations. Furthermore, the absolute suicide risk after expression of suicidal ideation is unknown. In this meta-analysis, we examined whether the expression of suicidal ideation predicted subsequent completed suicide in various populations, including both psychiatric and non-psychiatric populations.
A meta-analysis of cohort and case–control studies that assessed suicidal ideation as determinant for completed suicide in adults. Two independent reviewers screened 5726 articles for eligibility and extracted data of the 81 included studies. Pooled risk ratios were estimated in a random effects model stratified for different populations. Meta-regression analysis was used to determine suicide risk during the first year of follow-up.
The risk for completed suicide was clearly higher in people who had expressed suicidal ideation compared with people who had not, with substantial variation between the different populations: risk ratio ranging from 2.35 (95% confidence interval (CI) 1.43–3.87) in affective disorder populations to 8.00 (95% CI 5.46–11.7) in non-psychiatric populations. In contrast, the suicide risk after expression of suicidal ideation in the first year of follow-up was higher in psychiatric patients (risk 1.40%, 95% CI 0.74–2.64) than in non-psychiatric participants (risk 0.23%, 95% CI 0.10–0.54). Past suicide attempt-adjusted risk ratios were not pooled due to large underreporting.
Assessment of suicidal ideation is of priority in psychiatric patients. Expression of suicidal ideation in psychiatric patients should prompt secondary prevention strategies to reduce their substantial increased risk of suicide.
Li/S batteries have received too much attention due to their considerable theoretical energy density suitable for high energy applications. Here, we study the consequences of the SEI layer on internal resistance of the single battery cell due to polysulfide (PS) shuttling. The growth in resistance is related to the capacity fading of the cell. Using a model of series resistors, the total internal ionic resistance over cycling performance is expressed and compared for various nanostructured cathodes at different rates. It has been shown that SEI layer is the most significant factor in increasing of ionic resistance at the beginning of the battery aging, while electrode degradation and other phenomena are dominating resistance rise over higher cycles. We also demonstrate that cathodes with smaller equivalent porosity represent an excellent performance in preventing internal resistance enhancement.
GaN and its alloys are promising candidates for high temperature thermoelectric (TE) materials due to their high Seebeck coefficient and high thermal and mechanical stability. Moreover, these materials can overcome the toxicity concern of current Te-based TE materials, such as Bi2Te3 and PbTe. These materials have recently shown a higher Seebeck coefficient than that of SiGe in high temperature region because their large bandgap characteristic eliminates the bipolar conduction. In this study, we report the room temperature thermoelectric properties of p-type Mg doped GaN, grown by metalorganic chemical vapor deposition (MOCVD) on sapphire substrate with various carrier concentrations. Undoped and n-type GaN are also incorporated with p-type GaN films to make comparison. The structural, optical, electrical, and thermal properties of the samples were examined by X-ray diffraction, photoluminescence, van der Pauw hall-effect, and thermal gradient methods, respectively. The Seebeck coefficient ranging from 710-900µV/K at room temperature of Mg: GaN were observed, which further indicated their potential TE applications.
We present the analysis of HD 181068 which is one of the first triply eclipsing triple system discovered. Using Kepler photometry, ground based spectroscopic and interferometric measurements, we determined the stellar and orbital parameters of the system. We show that the oscillations observed in the red giant component of the system are tidally forced oscillations, while one of the most surprising results is that it does not show solar-like oscillations.
Illustrated identification keys are given for the superfamilies/families of insect parasitoids and the subfamilies, genera, and species of Braconidae reared from species of Choristoneura Lederer in the Nearctic Region. Goniozus floridanus (Ashmead) (Chrysidoidea: Bethylidae) represents the third superfamily of Hymenoptera, and Colpoclypeus florus (Walker) (Hymenoptera: Eulophidae) is added to the list of Chalcidoidea recorded from Choristoneura. Fifty species of Braconidae in 18 genera and 9 subfamilies are recorded parasitizing 11 Choristoneura species; almost half belong to the Microgastrinae. Eight braconids (16%) were found for the first time as parasitoids of Choristoneura. The first host record is given for Oncophanes californicus (Ashmead) (Hormiinae). Known insect parasitoids of Choristoneura spp. in the Nearctic Region include 230 species in 106 genera, about 75% of which attack only 1 or 2 Choristoneura species each. An additional 36 species are considered incorrectly associated with Choristoneura, an error rate of 14%. The Banchinae (Ichneumonidae, especially Glypta Gravenhorst), Pimplinae (Ichneumonidae), and Microgastrinae (Braconidae) made up the greatest proportion of parasitoids. No parasitoids have yet been recorded from five Nearctic Choristoneura species.
Energy efficiency in BOF process is related to hot metal and scrap
ratio and thus to production capacity potential and specific CO2
emissions. A thermal balance in the fume system, using a selected
metrology, can be calculated dynamically and provides a valuable
tool for investigating the process parameters that are relevant for
optimizing and controlling energy efficiency. The method and first
results are presented.
Theoretical work based on one-dimensional (1D) models indicates that Bi wires with diameter smaller than 50 nm can exhibit superior thermoelectric properties since the density of states at the Fermi level of a 1D system can be tuned to very high values. Recently, angle-resolved photoemission spectroscopy (ARPES) studies of Bi surfaces have shown that Bi nanowires support Rashba spin-orbit surface states, with high carrier densities of around 5×1012/cm−2, that have not been considered in current models of Bi nanowires. According to our estimates, the sheath of surface charge on Bi nanowires should contribute substantially to the thermopower of Bi nanowires. We carried out an experimental study of the transport properties and thermopower of bismuth nanowire arrays (NWA) with wire diameters ranging between 60 nm and 13 nm to investigate these phenomena. The Rashba interaction is a spin orbit interaction that is important for surfaces of materials consisting of heavy ion elements; thermoelectric materials frequently consist of these elements (i.e.PbTe) because they scatter phonons and form low thermal conductivity materials.
Slag splashing is a way of maintaining converters lining, started at the Fos steel
plant in December 2003. Systematic slag splashing on converters lining, by nitrogen
injection with the top lance, after tapping, protects refractory. The aim of the project
is to disconnect the two converters, from the refractory point of view, and to reach
a refractory lining lifetime of 5,000 heats.
Instrumented indentation and micro-Raman spectroscopy were used to investigate the mechanical and structural properties of Bombyx mori silk films. Twelve different films were prepared from B. mori silk fibroin protein using a variety of post-deposition processing treatments (e.g. soaking in methanol, soaking in water, stretching, and/or enzymatic etching). The results show that different treatments lead to changes in both the conformation of the silk fibroin protein and the mechanical properties of the films.
The mechanical properties of the mussel byssal thread have been investigated via nano-indentation, with the emphasis on the differences between the cuticle and the fibrous interior. The cuticle hardness was found to be 30–40% higher than that of the underlying fibrous interior. In contrast, the Young's moduli in the two regions were virtually identical to one another. Elemental analysis via energy dispersive spectroscopy indicated surprisingly high levels of Al and Br in the cuticle considering the low amounts found in seawater. A potential role of Al in byssal thread mechanics is discussed in light of the unique capability of the cuticle to accommodate strains of 70% by the underlying fibrils in the core without delamination.
The deformation behavior of both ion-implanted and deposited amorphous Si (a-Si) films has been studied using spherical nanoindentation, followed by analysis using Raman spectroscopy and cross-sectional transmission electron microscopy (XTEM). Indentation was carried out on both unannealed a-Si films (the so-called unrelaxed state) and in ion implanted films that were annealed to 450°C to fully relax the amorphous film. The dominant mode of deformation in unrelaxed films was via plastic flow of the amorphous phase rather than phase transformation, with measured hardness being typically 75–85% of that of crystalline Si. In contrast, deformation via phase transformation was clearly observed in the relaxed state of ion implanted a-Si, with the load-unload curves displaying characteristic discontinuities and Raman and XTEM indicating the presence of high-pressure crystalline phases Si-III and Si-XII following pressure release. In such cases the measured hardness was within 5% of that of the crystalline phase.
Mechanical characterization of polymeric thin films and small volume structures is critical to device development in industrial applications ranging from low-k dielectric microelectronic packaging films to engineered and natural biological substrata. Although nanoindentation has the potential to quantify mechanical properties of polymeric systems, the established analyses developed for metals and ceramics (eg, calculation of hardness and Young's modulus) do not capture key aspects of viscoelastoplastic deformation and are therefore not quantitatively applicable. Here, we present a set of complementary, nanoscale contact-based experimental approaches that together characterize specific energy absorption as a unique mechanical characteristic of polymers, and provide examples for a set of amorphous polymers.