The influence of grain size on the twinning stress of an Fe–15Mn–2Al–2Si–0.7C Twinning Induced Plasticity (TWIP) steel has been investigated. Five grain sizes were obtained using a combination of ...cold rolling and annealing. Electron backscatter diffraction (EBSD) analysis revealed that the material exhibited a typical cold rolled and annealed texture. Tensile testing showed the yield stress to increase with decreasing grain size, however, the ductility of the material was not substantially affected by a reduction in grain size. Cyclic tensile testing at sub-yield stresses indicated the accumulation of plastic strain with each cycle, consequently the nucleation stress for twinning was determined. The twin stress was found to increase with decreasing grain size. Furthermore, the amount of strain accumulated was greater in the coarser grain material. It is believed that this is due to a difference in the twin thickness, which is influenced by the initial grain size of the material. SEM and TEM analysis of the material deformed to 5% strain revealed thinner primary twins in the fine grain material compared to the coarse grain. TEM examination also showed the dislocation arrangement is affected by the grain size. Furthermore, a larger fraction of stacking faults was observed in the coarse-grained material. It is concluded that the twin nucleation stress and also the thickness of the deformation twins in a TWIP steel, is influenced by the initial grain size of the material. In addition grain refinement results in a boost in strength and energy absorption capabilities in the material.
ObjectivesEssential healthcare workers (HCW) uniquely serve as both COVID-19 healers and, potentially, as carriers of SARS-CoV-2. We assessed COVID-19-related stigma and bullying against HCW ...controlling for social, psychological, medical and community variables.DesignWe nested an analytical cross-sectional study of COVID-19-related stigma and bullying among HCW within a larger mixed-methods effort assessing COVID-19-related lived experience and impact. Adjusted OR (aOR) and 95% CIs evaluated the association between working in healthcare settings and experience of COVID-19-related bullying and stigma, controlling for confounders. Thematic qualitative analysis provided insight into lived experience of COVID-19-related bullying.SettingWe recruited potential participants in four languages (English, Spanish, French, Italian) through Amazon Mechanical Turk’s online workforce and Facebook.ParticipantsOur sample included 7411 people from 173 countries who were aged 18 years or over.FindingsHCW significantly experienced more COVID-19-related bullying after controlling for the confounding effects of job-related, personal, geographic and sociocultural variables (aOR: 1.5; 95% CI 1.2 to 2.0). HCW more frequently believed that people gossip about others with COVID-19 (OR: 2.2; 95% CI 1.9 to 2.6) and that people with COVID-19 lose respect in the community (OR: 2.3; 95% CI 2.0 to 2.7), both which elevate bullying risk (OR: 2.7; 95% CI 2.3 to 3.2, and OR: 3.5; 95% CI 2.9 to 4.2, respectively). The lived experience of COVID-19-related bullying relates frequently to public identities as HCW traverse through the community, intersecting with other domains (eg, police, racism, violence).InterpretationAfter controlling for a range of confounding factors, HCW are significantly more likely to experience COVID-19-related stigma and bullying, often in the intersectional context of racism, violence and police involvement in community settings.
Dislocation interactions at the crack nucleation site were investigated in near-alpha titanium alloy Ti-6242Si subjected to low cycle fatigue. Cyclic plastic strain in the alloy resulted in ...dislocation pile-ups in the primary alpha grains, nucleated at the boundaries between the primary alpha and the two-phase regions. These two phase regions provided a barrier to slip transfer between primary alpha grains. We suggest that crack nucleation occurred near the basal plane of primary alpha grains by the subsurface double-ended pile-up mechanism first conceived by Tanaka and Mura. Superjogs on the basal 〈a〉 dislocations were observed near the crack nucleation location. The two phase regions showed direct transmission of a3 dislocations between secondary alpha plates, transmitted through the beta ligaments as a010, which then decompose into (a/2)〈111〉 dislocation networks in the beta. The beta ligaments themselves do not appear to form an especially impenetrable barrier to slip, in agreement with the micropillar and crystal plasticity investigations of Zhang et al.
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•Dislocations below a low cycle fatigue crack initiation site in near-alpha Ti6242Si were investigated.•Dislocation pile-ups were observed, transferring easily between primary alpha grains.•Two phase alpha+beta regions showed direct transmission of a3 dislocations through the beta ligaments.•A subsurface double-ended pile-up in αp caused crack nucleation, consistent with the mechanism proposed by Tanaka and Mura.•The initiating facet was near-basal, the misorientation being associated with superjog basal dislocations.
Childhood trauma and adverse childhood experiences have a strong relationship with health disparities across the lifespan. Despite experiencing approximately doubled rates of trauma, Adverse ...Childhood Experiences (ACEs) are poorly characterized in deaf populations. We sought to characterize deaf-specific demographic factors and their association with multiple experiences of ACEs before the age of 18 years old. An analytical cross-sectional approach was used to ascertain associations of deaf-specific demographic factors and experiences with ACEs. The complete dataset included 520 participants for a total response rate of 56%. After adjusting for confounding effects, less severe hearing loss of 16-55 dB (2+ OR: 5.2, 4+ OR: 4.7), having a cochlear implant (2+ OR: 2.1, 4+ OR: 2.6), and not attending at least one school with signing access (2+ OR: 2.4, 4+ OR: 3.7) were significantly and independently associated with reported experiences of multiple ACEs. We conclude that factors associated with childhood hearing loss and language experiences increase risk of experiencing ACEs. Given the strong relationship between ACEs and poor social outcomes, early intervention clinical practice and health policies should consider interventions to support healthy home environments for deaf children.
The influence of early language and communication experiences on lifelong health outcomes is receiving increased public health attention. Most deaf children have non-signing hearing parents, and are ...at risk for not experiencing fully accessible language environments, a possible factor underlying known deaf population health disparities. Childhood indirect family communication-such as spontaneous conversations and listening in the routine family environment (e.g. family meals, recreation, car rides)-is an important source of health-related contextual learning opportunities. The goal of this study was to assess the influence of parental hearing status on deaf people's recalled access to childhood indirect family communication. We analyzed data from the Rochester Deaf Health Survey-2013 (n = 211 deaf adults) for associations between sociodemographic factors including parental hearing status, and recalled access to childhood indirect family communication. Parental hearing status predicted deaf adults' recalled access to childhood indirect family communication (χ2 = 31.939, p < .001). The likelihood of deaf adults reporting "sometimes to never" for recalled comprehension of childhood family indirect communication increased by 17.6 times for those with hearing parents. No other sociodemographic or deaf-specific factors in this study predicted deaf adults' access to childhood indirect family communication. This study finds that deaf people who have hearing parents were more likely to report limited access to contextual learning opportunities during childhood. Parental hearing status and early childhood language experiences, therefore, require further investigation as possible social determinants of health to develop interventions that improve lifelong health and social outcomes of the underserved deaf population.
To evaluate the effects of pre-gestational diabetes mellitus (PGDM) and gestational diabetes mellitus (GDM) on macrosomia and birth defects.
Existing birth registry data from the Perinatal Data ...System in Upstate New York was analysed. 650,914 women with a singleton term pregnancy (≥37 weeks) aged 18–55 years from 2004 to 2016 were included.
The prevalence of macrosomia in infants born to women with PGDM and GDM were 26.0% and 16.4%, respectively, higher than that in the controls (11.2%). Compared with the controls (0.8%), the PGDM and GDM groups had higher prevalence of any birth defect (1.8% and 1.0%). The PGDM group had the highest prevalence of cyanotic heart disease (0.6%). Moreover, the PGDM group had higher prevalence of cleft lip and palate, cleft palate alone, hypospadias and limb reduction defect compared to the GDM and control groups (p < 0.05). However, these birth defects in the GDM group were similar to those in the controls. Both the PGDM and GDM groups had significantly elevated odds of macrosomia, cyanotic heart disease and any birth defect than controls. The PGDM group had higher odds of cleft lip and palate, cleft palate alone, hypospadias and limb reduction defect.
Using the Perinatal Data System database, PGDM and GDM, especially PGDM, was associated with higher prevalence of macrosomia, cyanotic heart disease and any birth defect in singleton term pregnancy in Upstate New York. PGDM, not GDM had higher prevalence of cleft lip and palate, cleft palate alone, hypospadias and limb reduction defect.
Abstract
Background
Ecological disasters create dramatic changes as man-made and natural ecosystems adapt to their effects. In 2017, Hurricanes Irma and María devastated Puerto Rico. Public focus ...after such traumatic ecological events often neglects pre-existing community dynamics, heterogeneity of lived experience, and complexity of decision-making in the disaster context. We intended to better understand the lived experience of this ecological trauma in communities across ecosystems in Puerto Rico and among those displaced to Florida.
Method
We used the Critical Medical Ecological (CME) framework to assess the relative contribution of ecological dimensions on lived experience across community levels and time. We used qualitative methods with emic coding and etic mapping of salient constructs to the ecological model. In total, 96 people participated in 23 discussion encounters. Two people coded interviews in Spanish using Dedoose. We identified common themes in sequential order mapped to elements of the CME to approximate the participants’ temporal experience.
Results
Codes applied to the period of the hurricane’s landfall, traverse, and exit were markedly distinct from the other two periods (before and after) examined in this study: the experience of the hurricane’s strike was highly personal and, at this level, reflected a mix of sociocultural, biological, and abiotic factors. After the hurricanes, social and community factors re-emerged while new risks and conditions arose that were biological (e.g., leptospirosis, no food or water) or abiotic (e.g., unusable roads/bridges, structures destroyed), but created ongoing stressors and social needs for communities. As we found, the dynamics of the social and household landscape sometimes involved the decision to leave Puerto Rico altogether, or forced people to continually face and adapt to the ongoing collapse in basic services that were only slowly and differentially restored.
Conclusion
Lived experience across each stage of the hurricanes differed substantially from one another. Communities disrupted by ecological disaster are also frequently entangled within global economic and political histories and dependencies that could preclude recovery. Island nations are especially vulnerable to both climate-induced ecological change and political-economic exploitation. The ongoing health effect of the hurricane remains palpable in many communities of Puerto Rico and among the diaspora in Florida.
Background: Phthalates impair rodent testicular function and have been associated with antiandrogenic effects in humans, including decreased testosterone levels. Low testosterone in adult human males ...has been associated with increased prevalence of obesity, insulin resistance, and diabetes. Oobjects: Our objective in this study was to investigate phthalate exposure and its associations with abdominal obesity and insulin resistance. Methods: Subjects were adult U.S. male participants in the National Health and Nutrition Examination Survey (NHANES) 1999-2002. We modeled six phthalate metabolites with prevalent exposure and known or suspected antiandrogenic activity as predictors of waist circumference and log-transformed homeostatic model assessment (HOMA; a measure of insulin resistance) using multiple linear regression, adjusted for age, race/ethnicity, fat and total calorie consumption, physical activity level, serum cotinine, and urine creatinine (model 1); and adjusted for model 1 covariates plus measures of renal and hepatic function (model 2). Metabolites were mono-butyl phthalates (MBP), mono-ethyl phthalate (MEP), mono-(2-ethyl)-hexyl phthalate (MEHP), mono-benzyl phthalate (MBzP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP). Results: In model 1, four metabolites were associated with increased waist circumference (MBzP, MEHHP, MEOHP, and MEP; p-values ≤ 0.013) and three with increased HOMA (MBP, MBzP, and MEP; p-values ≤ 0.011). When we also adjusted for renal and hepatic function, parameter estimates declined but all significant results remained so except HOMA-MBP. Conclusions: In this national cross-section of U.S. men, concentrations of several prevalent phthalate metabolites showed statistically significant correlations with abdominal obesity and insulin resistance. If confirmed by longitudinal studies, our findings would suggest that exposure to these phthalates may contribute to the population burden of obesity, insulin resistance, and related clinical disorders.
RNA-seq is a high-throughput sequencing technology widely used for gene transcript discovery and quantification under different biological or biomedical conditions. A fundamental research question in ...most RNA-seq experiments is the identification of differentially expressed genes among experimental conditions or sample groups. Numerous statistical methods for RNA-seq differential analysis have been proposed since the emergence of the RNA-seq assay. To evaluate popular differential analysis methods used in the open source R and Bioconductor packages, we conducted multiple simulation studies to compare the performance of eight RNA-seq differential analysis methods used in RNA-seq data analysis (edgeR, DESeq, DESeq2, baySeq, EBSeq, NOISeq, SAMSeq, Voom). The comparisons were across different scenarios with either equal or unequal library sizes, different distribution assumptions and sample sizes. We measured performance using false discovery rate (FDR) control, power, and stability. No significant differences were observed for FDR control, power, or stability across methods, whether with equal or unequal library sizes. For RNA-seq count data with negative binomial distribution, when sample size is 3 in each group, EBSeq performed better than the other methods as indicated by FDR control, power, and stability. When sample sizes increase to 6 or 12 in each group, DESeq2 performed slightly better than other methods. All methods have improved performance when sample size increases to 12 in each group except DESeq. For RNA-seq count data with log-normal distribution, both DESeq and DESeq2 methods performed better than other methods in terms of FDR control, power, and stability across all sample sizes. Real RNA-seq experimental data were also used to compare the total number of discoveries and stability of discoveries for each method. For RNA-seq data analysis, the EBSeq method is recommended for studies with sample size as small as 3 in each group, and the DESeq2 method is recommended for sample size of 6 or higher in each group when the data follow the negative binomial distribution. Both DESeq and DESeq2 methods are recommended when the data follow the log-normal distribution.
Background
Major increases in the survival of people with Down syndrome during the last two generations have resulted in extended periods of adulthood requiring specialist care, which in turn ...necessitates greater understanding of the nature, timing and impact of comorbidities associated with the disorder.
Method
The prevalence of five comorbidities reported as common in adults with Down syndrome, visual impairment, hearing impairment, epilepsy, thyroid disorders and dementia was assessed by decade of life.
Results
From early adulthood, people with Down syndrome are at enhanced risk of developing new comorbidities and they may present with multiple conditions. Three specific challenges are identified and discussed: are comorbidities detected in a timely manner, is the clinical progress of the disorder adequately understood, and who is responsible for the provision of care?
Conclusions
Further detailed investigations into the development and treatment of comorbidities across the lifespan are needed for a successful longitudinal approach to healthcare in people with Down syndrome. Implementation of this approach will better inform healthcare providers to ensure continuity of care with advancing age.
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