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While rhenium has proven to be an ideal material in fast-cycling high-temperature applications such as rocket nozzles, its prohibitive cost limits its continued use and motivates a search for viable cost-effective substitutes. We show that a simple design principle that trades off average valence electron count and cost considerations proves helpful in identifying a promising pool of candidate substitute alloys: The Mo–Ru–Ta–W quaternary system. We demonstrate how this picture can be combined with a computational thermodynamic model of phase stability, based on high-throughput ab initio calculations, to further narrow down the search and deliver alloys that maintain rhenium’s desirable hcp crystal structure. This thermodynamic model is validated with comparisons to known binary phase diagram sections and corroborated by experimental synthesis and structural characterization demonstrating multiprinciple-element hcp solid-solution samples selected from a promising composition range.
Modern approaches to alloy design increasingly exploit the framework of computational thermodynamics and kinetics to guide the selection of alloy compositions and processing strategies, to achieve desired microstructures, and yield tailored properties. In this context, phase diagrams play a critical role and their assessment can represent a bottleneck in the design of new multicomponent systems. In recent years, it has become possible to accelerate this process through the coupling of the CALculation of PHAse Diagram (CALPHAD) computational thermodynamics framework with high-throughput quantum mechanical calculations. This article reviews recent developments and applications in this area, and discusses future opportunities for high-throughput calculations in the context of modeling kinetics, highlighting the important role of interfacial processes and atomic mobilities.
Flanged ventricular catheters are now used infrequently. Many patients with longstanding hydrocephalus still harbor these catheters, either as their current ventricular catheter, or as a retained catheter from a prior implant. The removal of flanged ventricular catheters is sometimes necessary, and may be challenging due to intraventricular adhesions. We describe the use of an endoscopic technique for the successful retrieval of flanged ventricular catheters in two patients. The technique described in this report may be helpful for patients that have flanged ventricular catheters that must be removed.
The authors developed a practical and clinically useful model to predict the risk of psychosis that utilizes clinical characteristics empirically demonstrated to be strong predictors of conversion to psychosis in clinical high-risk (CHR) individuals. The model is based upon the Structured Interview for Psychosis Risk Syndromes (SIPS) and accompanying clinical interview, and yields scores indicating one's risk of conversion.
Baseline data, including demographic and clinical characteristics measured by the SIPS, were obtained on 199 CHR individuals seeking evaluation in the early detection and intervention for mental disorders program at the New York State Psychiatric Institute at Columbia University Medical Center. Each patient was followed for up to 2 years or until they developed a syndromal DSM-4 disorder. A LASSO logistic fitting procedure was used to construct a model for conversion specifically to a psychotic disorder.
At 2 years, 64 patients (32.2%) converted to a psychotic disorder. The top five variables with relatively large standardized effect sizes included SIPS subscales of visual perceptual abnormalities, dysphoric mood, unusual thought content, disorganized communication, and violent ideation. The concordance index (c-index) was 0.73, indicating a moderately strong ability to discriminate between converters and non-converters.
The prediction model performed well in classifying converters and non-converters and revealed SIPS measures that are relatively strong predictors of conversion, comparable with the risk calculator published by NAPLS (c-index = 0.71), but requiring only a structured clinical interview. Future work will seek to externally validate the model and enhance its performance with the incorporation of relevant biomarkers.
Although the DSM is a widely used diagnostic guide, lengthy criteria sets can be problematic and provide the primary motivation to identify short-forms. Using the 11 diagnostic criteria provided by the DSM-5 for alcohol use disorder (AUD), the present study develops a data-driven method to systematically identify subsets and associated cut-offs that yield diagnoses as similar as possible to use all 11 criteria.
Relying on data from the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC-III), our methodology identifies diagnostic short-forms for AUD by: (1) maximizing the association between the sum scores of all 11 criteria with newly constructed subscales from subsets of criteria; (2) optimizing the similarity of AUD prevalence between the current DSM-5 rule and newly constructed diagnostic short-forms; (3) maximizing sensitivity and specificity of the short-forms against the current DSM-5 rule; and (4) minimizing differences in the accuracy of the short-form across chosen covariates. Replication is shown using NESARC-Wave 2.
More than 11 000 diagnostic short-forms for DSM-5 AUD can be created and our method narrows down the optimal choices to eight. Results found that ‘Neglecting major roles’ and ‘Activities given up’ could be dropped with practically no change in who is diagnosed (specificity = 100%, sensitivity ⩾ 99.6%) or the severity of those diagnosed (κ = 0.97).
With a continuous improvement model adopted by the APA for DSM revisions, we offer a data-driven tool (a SAS Macro) that identifies diagnostic short-forms in a systematic and reproducible way to help advance potential improvements in future DSM revisions.
Since 2012–2016 an increased number of listeriosis cases, especially from one region of the Czech Republic, were observed. Most of them were caused by strains of serotype 1/2a, clonal complex 8, indistinguishable by pulsed-field gel electrophoresis. Twenty-six human cases were reported, including two neonatal cases in twins. Three cases were fatal. The typing of Listeria monocytogenes isolates from food enabled to confirm a turkey meat delicatessen as the vehicle of infection for this local outbreak in the Moravian-Silesian Region. The food strains belonging to identical pulsotype were isolated from ready-to-eat turkey meat products packaged by the same producer between 2012 and 2016. This fact confirms that the described L. monocytogenes outbreak strain probably persisted in the environment of the aforementioned food-processing plant over several years. Whole-genome sequencing confirmed a very close relationship (zero to seven different alleles) between isolates from humans, foods and swabs from the environment of the food-processing plant under investigation.
A cadmium chloride activation treatment is essential for the production of high efficiency cadmium telluride (CdTe) solar cells. However, the effects of the treatment on the distributions of chlorine and sulphur within the device are not fully understood. Here, the detailed locations of chlorine and sulphur in a treated CdTe cell are determined in three dimensions by high resolution dynamic SIMS measurements. Chlorine is found to be present in grain boundaries, grain interiors, extended defects within the grain interiors, at the front interface, and in the cadmium sulphide layer. In each of these regions, the chlorine is likely to have significant effects on local electronic properties of the material, and hence overall device performance. Sulphur is found to have a U-shaped diffusion profile within CdTe grains, indicating a mixed grain boundary and lattice diffusion regime.
Evidence in support of the Developmental Origins of Health and Disease (DOHaD) hypothesis has reached the level where it can appropriately be used to inform practice. DOHaD informed interventions supporting primary noncommunicable disease risk reduction should target the pre- and periconceptional periods, pregnancy, lactation, childhood and adolescence. Such interventions are dependent on a health workforce (including dietitians, nurses, midwives, doctors, and nutrition teachers), that has a deep understanding of DOHaD concepts. This study assessed development of awareness of DOHaD concepts during undergraduate health professional training programs. Using a cross-sectional design, a standardized questionnaire was completed by Year 1–4 undergraduate students studying nutrition in Japan (n=309) and Year 1–3 nursing students in New Zealand (n=151). On entry to undergraduate study, most students had no awareness of the terms ‘DOHaD’ or ‘First 1000 Days’. While awareness reached 60% by Year 3 in courses that included DOHaD-related teaching, this remains inadequate. More than 95% of Year 1 undergraduates in both countries demonstrated an appreciation of associations between maternal nutrition and fetal health. However, awareness of associations between parental health status and/or nutritional environment and later-life health was low. While levels of awareness increased across program years, overall awareness was less than optimal. These results indicate evidence of some focus on DOHaD-related content in curricula. We argue that DOHaD principles should be one pillar around which health training curricula are built. This study indicates a need for the DOHaD community to engage with faculties in curriculum development.
Early detection of karyotype abnormalities, including aneuploidy, could aid producers in identifying animals which, for example, would not be suitable candidate parents. Genome-wide genetic marker data in the form of single nucleotide polymorphisms (SNPs) are now being routinely generated on animals. The objective of the present study was to describe the statistics that could be generated from the allele intensity values from such SNP data to diagnose karyotype abnormalities; of particular interest was whether detection of aneuploidy was possible with both commonly used genotyping platforms in agricultural species, namely the Applied BiosystemsTM AxiomTM and the Illumina platform. The hypothesis was tested using a case study of a set of dizygotic X-chromosome monosomy 53,X sheep twins. Genome-wide SNP data were available from the Illumina platform (11 082 autosomal and 191 X-chromosome SNPs) on 1848 male and 8954 female sheep and available from the AxiomTM platform (11 128 autosomal and 68 X-chromosome SNPs) on 383 female sheep. Genotype allele intensity values, either as their original raw values or transformed to logarithm intensity ratio (LRR), were used to accurately diagnose two dizygotic (i.e. fraternal) twin 53,X sheep, both of which received their single X chromosome from their sire. This is the first reported case of 53,X dizygotic twins in any species. Relative to the X-chromosome SNP genotype mean allele intensity values of normal females, the mean allele intensity value of SNP genotypes on the X chromosome of the two females monosomic for the X chromosome was 7.45 to 12.4 standard deviations less, and were easily detectable using either the AxiomTM or Illumina genotype platform; the next lowest mean allele intensity value of a female was 4.71 or 3.3 standard deviations less than the population mean depending on the platform used. Both 53,X females could also be detected based on the genotype LRR although this was more easily detectable when comparing the mean LRR of the X chromosome of each female to the mean LRR of their respective autosomes. On autopsy, the ovaries of the two sheep were small for their age and evidence of prior ovulation was not appreciated. In both sheep, the density of primordial follicles in the ovarian cortex was lower than normally found in ovine ovaries and primary follicle development was not observed. Mammary gland development was very limited. Results substantiate previous studies in other species that aneuploidy can be readily detected using SNP genotype allele intensity values generally already available, and the approach proposed in the present study was agnostic to genotype platform.
Changes in body condition score and other linear type traits can be indicative of changes in body energy balance in dairy cattle (Coffey et al., 2003). As an animal proceeds through her lactation it is expected that body shape and fatness levels will change both with peaks and troughs of lactation as well as changes as the animal grows and matures. Wall et al. (2005) showed that udder support (US) was correlated to fertility; cows with weaker udders had poorer fertility. If there are differences between animals in terms of how their udders grow and mature across the first lactation, this could be indicative of health and fertility problems later in life. The aim of this study was to examine how type traits recorded in the national dairy population change over the first lactation and if there is a difference between sires in the type profiles of their daughters.
Fertility has been shown to have an unfavourable genetic relationship with milk production in Holsteins so continued selection for milk production will exacerbate the decline in fertility in the absence of information on daughter fertility. The only way to reverse this genetic trend is to breed dairy cows additionally for fertility. But dairy farmers have historically had no access to fertility information when they purchase semen. It is therefore vital that fertility is included in selection programmes and that farmers can choose to inseminate their cows with semen from bulls with a positive predicted transmitting ability (PTA) for daughter fertility. Although of low heritability, fertility traits have been shown to have sufficient genetic variation and have recently been made available nationally for the Holstein-Friesian breed (Wall et al., 2003). The aim of this study was to investigate the feasibility of estimating fertility indices for Ayrshire (AYR), Guernsey (GUE) and Jersey (JER) dairy cows.
Cattle breeders, farmers and vets believe that the decline in fertility seen in recent years can be partially attributed to changes in rump angle with selection being for more angular cows. This suggests that animals with pin bones that sit above the hip bones (high rump angle) will have poorer fertility. Few studies have shown a significant relationship between fertility and rump traits. This study investigates the popular belief that high rump angle equates to poor fertility by examining the genetic and phenotypic correlation between rump angle and fertility traits. The relationship between rump angle and fertility was also examined to see if there was an intermediate optimum or threshold of rump angle for good/bad fertility. The correlation of other type traits (udder and composite traits) with fertility was also examined to see if they had potential to add information to the estimation of fertility breeding values.
We have recently developed a Fertility Index for UK dairy cattle (Wall et al., 2003). After examining national data it was decided that the Fertility Index should be based on sire PTAs for calving interval (CI) and nonreturn rate (NR) after 56 days weighted by their relative economic weights. However, just under half of the available bulls have no milking daughters in the UK. It would take about 4 years from the time of first use in the UK, for a bull to have sufficient daughters for a reliable fertility proof. Waiting this long for fertility information on which to base selection decisions will slow genetic progress and is undesirable as many of these bulls could have fertility proofs in their country of first test. This study examines the feasibility of converting foreign fertility proofs to UK equivalents.
Inbreeding depression leads to the reduction of the mean phenotypic value. There has been a steady increase in inbreeding (F) in the UK since the introduction of reproductive techniques (AI, MOET). There has been an increase in the percent Holstein (%H) in the UK population due to the influx of North American Holstein genes. Crossing these Holsteins to British Friesians can result in the favourable effect of heterosis (het), whereby crossbred progeny out-perform the mid-parent mean for that trait. Of the heterosis in the F1 population, a proportion is lost due to recombination (rec) between parental line genes and is a measure of the epistatic interaction of genes. The purpose of this study was to examine the impact of nonadditive genetic effects (F, het, rec, %H) on the estimation of dairy cow fertility breeding values in the UK.
Body dissatisfaction and depressive symptoms are commonly experienced during adolescence and increase the risk of adverse health outcomes, especially eating disorders. However, the dominant temporal associations between these two experiences (i.e., whether one is a risk factor for the other or the two are mutually reinforcing) has yet to be fully explored. We examined the associations between body dissatisfaction and depressive symptoms assessed at baseline and 5- and 10-year follow-up in younger (M age = 12.9 years at baseline, 56% female, n = 577) and older (M age = 15.9 years at baseline, 57% female, n = 1,325) adolescent cohorts assessed as part of Project Eating Among Teens and Young Adults. Associations between body dissatisfaction and depressive symptoms were examined using cross-lagged models. For females, the dominant directionality was for body dissatisfaction predicting later depressive symptoms. For males, the picture was more complex, with developmentally sensitive associations in which depressive symptoms predicted later body dissatisfaction in early adolescence and early adulthood, but the reverse association was dominant during middle adolescence. These findings suggest that interventions should be tailored to dynamic risk profiles that shift over adolescence and early adulthood, and that targeting body dissatisfaction at key periods during development may have downstream impacts on depressive symptoms.