Bridging necking and shear-banding mediated tensile failure in glasses

The transition between necking-mediated tensile failure of glasses, at elevated temperatures and/or low strain-rates, and shear-banding-mediated tensile failure, at low temperatures and/or high strain-rates, is investigated using tensile experiments on metallic glasses and atomistic simulations. We experimentally and simulationally show that this transition occurs through a sequence of macroscopic failure patterns, parametrized by the ultimate tensile strength. Quantitatively analyzing the spatiotemporal dynamics preceding failure, using large scale atomistic simulations corroborated by experimental fractography, reveals how the collective evolution and mutual interaction of shear-driven plasticity and dilation-driven void formation (cavitation) control the various macroscopic failure modes. In particular, we find that at global failure, the size of the largest cavity in the loading direction exhibits a nonmonotonic dependence on the temperature at a fixed strain rate, which is rationalized in terms of the interplay between shear- and dilation-driven plasticity. We also find that the size of the largest cavity scales with the cross-sectional area of the undeformed sample. These results shed light on tensile failure of glasses, and highlight the need to develop elasto-plastic constitutive models of glasses incorporating both shear- and dilation-driven irreversible processes

The influence of copreneurial relationships on the restaurant industry : a study in the Nelson Mandela Metropole

Entrepreneurship plays an important role in the South African economy, especially in light of the recent global recession. For family businesses, namely copreneurs in the restaurant industry, to be afforded a better opportunity to perform better and be viable and sustainable, a deeper understanding and insight into their dynamics is required. Researching and implementing strategies or recommendations to improve the influence of copreneurial relationships in the restaurant industry is fundamentally important to the growth and sustainability of restaurants in the hospitality industry, in the Nelson Mandela Metropole (NMM). However, no known studies have been performed in this area of copreneurship. This study sought to present exploratory research in the rapidly expanding and critically important sector family business, namely copreneurships specifically in the restaurant industry in the NMM, in South Africa. The primary research objective of this study is to gain a deeper understanding and insight into the influence of copreneurial relationships in the restaurant industry in the NMM. A phenomenological, or qualitative, research paradigm, through the use of focused one-on-one interviews, was employed to probe and analyse relational factors of copreneurial relationships. A qualifying questionnaire was constructed to determine the most effective sample for the study followed by an extensive questionnaire constructed to probe into the demographics and the specifically identified relational factors of the ten qualifying copreneurships. The collected data was then analysed and inferences were derived from the findings of the study. The findings revealed that what restaurant copreneurships perceive to be the most important relationship factors are very closely linked to the relationship factors perceived important to personally work on and improve. Of the relational factors considered for this study, namely: Commitment, communication, conflict, division of labour, emotional attachment, relationship bond, respect, spousal harmony, trust and the spousal values system, several factors stood out as those baring greatest influence on copreneurial relationships and their business. This study, from an analysis of the collected interview data and subsequent findings, determined communication to stand out above all other factors as being the most critical to copreneurial relationships. All other factors emanated as important but division of labour, values system, respect and relationship bond were revealed as extremely important, just behind communication. In light of these findings, as well as the discovery of other affecting factors, the study concluded that the viability and sustainability of restaurant copreneurships is of paramount significance. In order to facilitate this, copreneurial couples must cherish their relationships with each other, understand the dynamics of the relational factors affecting their relationships, invoke relational improvements for their viability and sustainability, not neglect family responsibilities and preservation in light of business needs and work together as a team

A versatile polyacrylamide gel electrophoresis based sulfotransferase assay

<p>Abstract</p> <p>Background</p> <p>Sulfotransferases are a large group of enzymes that regulate the biological activity or availability of a wide spectrum of substrates through sulfation with the sulfur donor 3'-phosphoadenosine-5'-phosphosulfate (PAPS). These enzymes are known to be difficult to assay. A convenient assay is needed in order to better understand these enzymes.</p> <p>Results</p> <p>A universal sulfotransferase assay method based on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) is described. This assay has been successfully applied to substrates as small as α-naphthol and as big as proteoglycans. As examples, we present the assays for recombinant human CHST4, TPST1, CHST3 and HS6ST1. In order to assess whether a small molecule can be applicable to this type of assay, a method to estimate the relative mobility of a molecule to PAPS is also presented. The estimated relative mobilities of various sulfated small molecules generated by SULT1A1, SULT1E1, SULT2A1 and CHST4 are in the range of ± 0.2 of the actual relative mobilities.</p> <p>Conclusion</p> <p>The versatility of the current method comes from the ability that SDS-PAGE can separate proteins and small molecules according to different parameters. While mobilities of proteins during SDS-PAGE are inversely related to their sizes, mobilities of small molecules are positively related to their charge/mass ratios. The predicted relative mobility of a product to PAPS is a good indicator of whether a sulfotransferase can be assayed with SDS-PAGE. Because phosphorylation is most similar to sulfation in chemistry, the method is likely to be applicable to kinases as well.</p

Value chain analysis of carp fish seed farms in some selected areas of Mymensingh district in Bangladesh

This study is an attempt to analyze the prevailing value chain of fish seed farms in some selected areas of Mymensingh district in Bangladesh. Data were collected from 280 fish seed farms owners (56) and traders (224) covering four Upazilas of Mymensingh district namely Mymensingh Sadar, Gauripur, Muktagacha, and Trishal from the period of July 2019 to October 2019 through purposive random sampling technique. Three important fish seed species of carp; namely Rui, Catla, Mrigel were selected to address the following objectives: typical value chain map and marketing system of fish seed farms, determination of the net value addition of fish seed production and marketing, and problems impacting different actors in the value chain. Total net marketing margin per 10 Kg. spawn and per 100000 pieces’ fingerlings are Tk. 20204 (190.43 USD) and Tk. 43148 (406.69 USD), respectively. Among all three intermediaries, the net marketing margin of the retailer is the highest. A large percentage of value addition is covered by paiker for both cases and that is 20.85% and 31.2%. The study finds that fish seed farms with hatcheries are more profitable than fish seed farms with nursery. The yearly net return from spawn production in the hatchery is Tk. 4324775 (40763.15 USD) and from fingerling production in the nursery is Tk. 2388126 (22509.27 USD). The owners and traders have currently been facing some difficulties. Lack of information about good quality seed, the higher price of inputs, and lack of extension service is some of the examples. If these problems could be solved, fish seed farms and market intermediaries could earn a higher profit than the existing level

Survival of children with trisomy 13 and trisomy 18: A multi-state population-based study

Trisomy 13 (T13) and trisomy 18 (T18) are among the most prevalent autosomal trisomies. Both are associated with a very high risk of mortality. Numerous instances, however, of long-term survival of children with T13 or T18 have prompted some clinicians to pursue aggressive treatment instead of the traditional approach of palliative care. The purpose of this study is to assess current mortality data for these conditions. This multi-state, population-based study examined data obtained from birth defect surveillance programs in nine states on live-born infants delivered during 1999–2007 with T13 or T18. Information on children’s vital status and selected maternal and infant risk factors were obtained using matched birth and death certificates and other data sources. The Kaplan–Meier method and Cox proportional hazards models were used to estimate age-specific survival probabilities and predictors of survival up to age five. There were 693 children with T13 and 1,113 children with T18 identified from the participating states. Among children with T13, 5-year survival was 9.7%; among children with T18, it was 12.3%. For both trisomies, gestational age was the strongest predictor of mortality. Females and children of non-Hispanic black mothers had the lowest mortality. Omphalocele and congenital heart defects were associated with an increased risk of death for children with T18 but not T13. This study found survival among children with T13 and T18 to be somewhat higher than those previously reported in the literature, consistent with recent studies reporting improved survival following more aggressive medical intervention for these children

Alcohol Policy, Social Context, and Infant Health: The Impact of Minimum Legal Drinking Age

Objective: The minimum legal drinking age (MLDA) was increased in the U.S. in the late 1980s in an effort to reduce intoxication-associated injuries, especially those related to motor vehicle accidents. This paper explores distal (secondary) effects of changing MLDA on indices of infant health, and whether changes in drinking behaviors or birth composition contributed to these effects. Methods: State- and year-fixed-effects models are used to analyze the relationship between MLDA, drinking behaviors, and birth outcomes. We studied the effects of different MLDA (age 18, 19, 20, or 21 years) when potential mothers were 14 years old by merging two population-based datasets, the Natality Detailed Files and the Behavioral Risk Factor Surveillance System between 1985 and 2002. Results: A MLDA of 18 years old (when potential mothers were 14 years old) increased the prevalence of low birth weight, low Apgar scores, and premature births. Effects were stronger among children born to black women compared with white women. Moreover, a younger MLDA was associated with an increasing proportion of very young and high school dropouts for black women. Furthermore, older MLDA laws at age 14 years decreased the prevalence of binge drinking among black women. Conclusions: Increasing the MLDA had longer term, distal impacts beyond the initially intended outcomes, specifically on birth outcomes (particularly among infants born to black women) as well as school drop-outs and binge drinking patterns among black young females. The older MLDA, intended initially to reduce problematic drinking behaviors, appeared to alter broader social contexts that influenced young women during their early childbearing years

Risks of nonchromosomal birth defects, small-for-gestational age birthweight, and prematurity with in vitro fertilization: effect of number of embryos transferred and plurality at conception versus at birth

PURPOSE: Excess embryos transferred (ET) (> plurality at birth) and fetal heartbeats (FHB) at 6 weeks' gestation are associated with reductions in birthweight and gestation, but prior studies have been limited by small sample sizes and limited IVF data. This analysis evaluated associations between excess ET, excess FHB, and adverse perinatal outcomes, including the risk of nonchromosomal birth defects. METHODS: Live births conceived via IVF from Massachusetts, New York, North Carolina, and Texas included 138,435 children born 2004-2013 (Texas), 2004-2016 (Massachusetts and North Carolina), and 2004-2017 (New York) were classified by ET and FHB. Major birth defects were reported by statewide registries within the first year of life. Logistic regression was used to estimate adjusted odds ratios (AORs) and 95% CIs of the risks of a major nonchromosomal birth defect, small-for-gestational age birthweight (SGA), low birthweight (LBW), and preterm birth (≤36 weeks), by excess ET, and excess ET + excess FHB, by plurality at birth (singletons and twins). RESULTS: In singletons with [2 ET, FHB =1] and [≥3 ET, FHB=1], risks [AOR (95% CI)] were increased, respectively, for major nonchromosomal birth defects [1.13 (1.00-1.27) and 1.18 (1.00-1.38)], SGA [1.10 (1.03-1.17) and 1.15 (1.05-1.26)], LBW [1.09 (1.02-1.13) and 1.17 (1.07-1.27)], and preterm birth [1.06 (1.00-1.12) and 1.14 (1.06-1.23)]. With excess ET + excess FHB, risks of all adverse outcomes except major nonchromosomal birth defects increased further for both singletons and twins. CONCLUSION: Excess embryos transferred are associated with increased risks for nonchromosomal birth defects, reduced birthweight, and prematurity in IVF-conceived births

Design and feasibility testing of a novel group intervention for young women who binge drink in groups

BackgroundYoung women frequently drink alcohol in groups and binge drinking within these natural drinking groups is common. This study describes the design of a theoretically and empirically based group intervention to reduce binge drinking among young women. It also evaluates their engagement with the intervention and the acceptability of the study methods.MethodsFriendship groups of women aged 18–35 years, who had two or more episodes of binge drinking (>6 UK units on one occasion; 48g of alcohol) in the previous 30 days, were recruited from the community. A face-to-face group intervention, based on the Health Action Process Approach, was delivered over three sessions. Components of the intervention were woven around fun activities, such as making alcohol free cocktails. Women were followed up four months after the intervention was delivered. Results The target of 24 groups (comprising 97 women) was recruited. The common pattern of drinking was infrequent, heavy drinking (mean consumption on the heaviest drinking day was UK 18.1 units). Process evaluation revealed that the intervention was delivered with high fidelity and acceptability of the study methods was high. The women engaged positively with intervention components and made group decisions about cutting down. Twenty two groups set goals to reduce their drinking, and these were translated into action plans. Retention of individuals at follow up was 87%.ConclusionsThis study successfully recruited groups of young women whose patterns of drinking place them at high risk of acute harm. This novel approach to delivering an alcohol intervention has potential to reduce binge drinking among young women. The high levels of engagement with key steps in the behavior change process suggests that the group intervention should be tested in a full randomised controlled trial

Transcriptome changes in age-related macular degeneration

Age-related macular degeneration (AMD) is a debilitating, common cause of visual impairment. While the last decade has seen great progress in understanding the pathophysiology of AMD, the molecular changes that occur in eyes with AMD are still poorly understood. In the current issue of Genome Medicine, Newman and colleagues present the first systematic transcriptional profile analysis of AMD-affected tissues, providing a comprehensive set of expression data for different regions (macula versus periphery), tissues (retina versus retinal pigment epithelium (RPE)/choroid), and disease state (control versus early or advanced AMD). Their findings will serve as a foundation for additional systems-level research into the pathogenesis of this blinding disease