Prediction of thermal cycling induced matrix cracking

Thermal fatigue has been observed to cause matrix cracking in laminated composite materials. A method is presented to predict transverse matrix cracks in composite laminates subjected to cyclic thermal load. Shear lag stress approximations and a simple energy-based fracture criteria are used to predict crack densities as a function of temperature. Prediction of crack densities as a function of thermal cycling is accomplished by assuming that fatigue degrades the material's inherent resistance to cracking. The method is implemented as a computer program. A simple experiment provides data on progressive cracking of a laminate with decreasing temperature. Existing data on thermal fatigue is also used. Correlations of the analytical predictions to the data are very good. A parametric study using the analytical method is presented which provides insight into material behavior under cyclical thermal loads

Association of prior depressive symptoms and suicide attempts with subsequent victimisation - analysis of population-based data from the Adult Psychiatric Morbidity Survey

Background: Symptoms of mental disorder, particularly schizophrenia, predispose to victimisation. Much less is known about the relationship between depressive symptoms and later victimisation in the general population, the influence of these symptoms on types of subsequent victimisation, or the role of symptom severity. We investigated this in nationally representative data from the UK. Methods: Data were from the Adult Psychiatric Morbidity Survey 2007. Multivariable logistic regressions estimated association between: a. prior depressive symptoms, and b. prior depressive symptoms with suicide attempt, and types of more recent victimisation. Gender-specific associations were estimated using multiplicative interactions. Results: Prior depressive symptoms were associated with greater odds of any recent intimate partner violence (IPV), emotional IPV, sexual victimisation, workplace victimisation, any victimisation, and cumulative victimisation (adjusted odds ratio (aOR) for increasing types of recent victimisation: 1.47, 95% confidence interval (CI): 1.14, 1.89). Prior depressive symptoms with suicide attempt were associated with any recent IPV, emotional IPV, any victimisation, and cumulative victimisation (aOR for increasing types of recent victimisation: 2.33, 95%: 1.22, 4.44). Limitations: Self-reported recalled data on previous depressive symptoms, may have limited accuracy. Small numbers of outcomes for some comparisons resulted in imprecision of these estimates. Conclusion: Aside from severe mental illness such as schizophrenia, previous depressive symptoms in the general population are associated with greater subsequent victimisation. Men and women with prior depressive symptoms may be vulnerable to a range of types of victimisation, and may benefit from interventions to reduce this vulnerability

Constitutional Law-Self-Incrimination- Denial of Privilege to General Partner Holding Subpoenaed Books and Records of Limited Partnership

A special agent of the Internal Revenue Service sought enumerated books and records of four New York limited partnerships in connection with petitioner\u27s tax liability for prior years. A subpoena duces tecum was issued directing petitioner to produce the records, which were in his possession as general partner. Petitioner, his son, and his son-in-law were the general partners of each limited partnership involved, with limited partners ranging from twenty-five to 119 in number and capitalization from 225,000 dollars to 2,740,000 dollars. The partnerships, together with a management company, were housed in a single office with a staff of one secretary. Petitioner claimed that the order to deliver the books and records to the special agent violated his constitutional privilege against self-incrimination. On appeal from a district court order upholding the subpoena, held, affirmed. Where the size and extent of limited partnership operations show that a general partner\u27s personal interest in the company books and records is subordinate to the interest of the company as a whole, the partner is holding the books in a purely representative capacity and may not claim for himself the privilege against self-incrimination as to the books subpoenaed. United States v. Silverstein, 314 F.2d 789 (2d Cir. 1963)

Eminent Domain-Urban Renewal-Broader Powers to Take Private Property for Public Use

Defendant city instituted a comprehensive urban redevelopment plan under which condemnation and purchase of blighted property would be followed by extensive demolition and clearance. This land was then to be sold subject to certain use restrictions to private developers, chiefly for light industry. Plaintiff, an owner of real estate described as improved and enhanced with . . . a good, sound, sanitary, modem and well-kept building, brought an action in a lower state court seeking a declaratory judgment against the constitutionality of the Washington Urban Renewal Law, and an injunction to prevent defendant city from condemning his property under the statute. The owner contended that resale to private persons would constitute use of the eminent domain power for a private purpose. The trial court gave summary judgment for the defendant city. On appeal, held, affirmed, by a five-to-four decision. Condemnation, acquisition, and demolition by public authority of substandard or blighted areas of urban land is a public use justifying the exercise of the eminent domain power, and subsequent resale of cleared land to private persons is only incidental to the main, constitutionally valid purpose. Miller v. City of Tacoma, 61 Wash. 2d 374, 378 P.2d 464 (1963)

Self-monitoring for improving control of blood pressue in patients with hypertension

The objective of this review is to determine the effect of SBPM in adults with hypertension on blood pressure control as compared to OBPM or usual care

Prediction of thermal cycling induced cracking in polymer matrix composites

This report summarizes the work done in the period February 1993 through July 1993 on the 'Prediction of Thermal Cycling Induced Cracking In Polymer Matrix Composites' program. An oral presentation of this work was given to Langley personnel in September of 1993. This document was prepared for archival purposes. Progress studies have been performed on the effects of spatial variations in material strength. Qualitative agreement was found with observed patterns of crack distribution. These results were presented to NASA Langley personnel in November 1992. The analytical methodology developed by Prof. McManus in the summer of 1992 (under an ASEE fellowship) has been generalized. A method for predicting matrix cracking due to decreasing temperatures and/or thermal cycling in all plies of an arbitrary laminate has been implemented as a computer code. The code also predicts changes in properties due to the cracking. Experimental progressive cracking studies on a variety of laminates were carried out at Langley Research Center. Results were correlated to predictions using the new methods. Results were initially mixed. This motivated an exploration of the configuration of cracks within laminates. A crack configuration study was carried out by cutting and/or sanding specimens in order to examine the distribution of cracks within the specimens. These investigations were supplemented by dye-penetrant enhanced X-ray photographs. The behavior of thin plies was found to be different from the behavior of thicker plies (or ply groups) on which existing theories are based. Significant edge effects were also noted, which caused the traditional metric of microcracking (count of cracks on a polished edge) to be very inaccurate in some cases. With edge and configuration taken into account, rough agreement with predictions was achieved. All results to date were reviewed with NASA Langley personnel in September 1993

Modeling of outgassing and matrix decomposition in carbon-phenolic composites

A new release rate equation to model the phase change of water to steam in composite materials was derived from the theory of molecular diffusion and equilibrium moisture concentration. The new model is dependent on internal pressure, the microstructure of the voids and channels in the composite materials, and the diffusion properties of the matrix material. Hence, it is more fundamental and accurate than the empirical Arrhenius rate equation currently in use. The model was mathematically formalized and integrated into the thermostructural analysis code CHAR. Parametric studies on variation of several parameters have been done. Comparisons to Arrhenius and straight-line models show that the new model produces physically realistic results under all conditions

Modeling of outgassing and matrix decomposition in carbon-phenolic composites

Work done in the period Jan. - June 1994 is summarized. Two threads of research have been followed. First, the thermodynamics approach was used to model the chemical and mechanical responses of composites exposed to high temperatures. The thermodynamics approach lends itself easily to the usage of variational principles. This thermodynamic-variational approach has been applied to the transpiration cooling problem. The second thread is the development of a better algorithm to solve the governing equations resulting from the modeling. Explicit finite difference method is explored for solving the governing nonlinear, partial differential equations. The method allows detailed material models to be included and solution on massively parallel supercomputers. To demonstrate the feasibility of the explicit scheme in solving nonlinear partial differential equations, a transpiration cooling problem was solved. Some interesting transient behaviors were captured such as stress waves and small spatial oscillations of transient pressure distribution

Suicide and self-harm in Britain: researching risk and resilience using UK surveys

Aim The main aim of this study was to raise awareness of surveys that could be used to inform self-harm and suicide prevention work. We asked: What UK survey datasets are available for research? What aspects of people’s lives are associated with self-harm and attempted suicide? How do statistical findings resonate with people’s lived experience? What implications do they see? Findings Survey analyses revealed that risk factors for self-harm are wide ranging and include: Mental health Physical health and health behaviours Social relationships Stressful events Employment and financial circumstances Identity and demographics Many different factors are independently associated with self-harm. There is a dose relationship, with more exposure to a factor linked with increased risk. Risks are cumulative that is, exposure to multiple factors is associated with greater risk. Through facilitated consultation, men with lived experience, bereaved family members, and practitioners identified recommendations for responding to suicidal distress in men. These related to the following three main areas: 1. Recognising need: who is ‘ill enough’? Permission - men said that they often did not know they were entitled to help Ask - people who outwardly appear to be functioning may not be Persistence - ask and offer help more than once. 2. Facilitating access: right words, time and place What is available - support is needed with ongoing stress as well as for crises Find the words - men wanted examples of how to ask for help Allow time - employers expect recovery to be swift, some men felt rushed to come off medications or were discharged from services they still needed. 3. Adjusting delivery: equal engagement Power - some were uncomfortable with service dynamics, preferring peer support Every service contact counts - negative contacts had particular impact Safe spaces - may be different for men and women. Methods There were three strands of work: Secondary analysis of nine survey series, spanning more than twenty years Linkage of 144,000 survey participants to information on whether they were alive in 2013 and whether they had taken their own life Facilitated consultation, through depth interviews with people with lived experience

Association of Lipid-Related Genetic Variants with the Incidence of Atrial Fibrillation: The AFGen Consortium

BACKGROUND: Several studies have shown associations between blood lipid levels and the risk of atrial fibrillation (AF). To test the potential effect of blood lipids with AF risk, we assessed whether previously developed lipid gene scores, used as instrumental variables, are associated with the incidence of AF in 7 large cohorts. METHODS: We analyzed 64,901 individuals of European ancestry without previous AF at baseline and with lipid gene scores. Lipid-specific gene scores, based on loci significantly associated with lipid levels, were calculated. Additionally, non-pleiotropic gene scores for high-density lipoprotein cholesterol (HDLc) and low-density lipoprotein cholesterol (LDLc) were calculated using SNPs that were only associated with the specific lipid fraction. Cox models were used to estimate the hazard ratio (HR) and 95% confidence intervals (CI) of AF per 1-standard deviation (SD) increase of each lipid gene score. RESULTS: During a mean follow-up of 12.0 years, 5434 (8.4%) incident AF cases were identified. After meta-analysis, the HDLc, LDLc, total cholesterol, and triglyceride gene scores were not associated with incidence of AF. Multivariable-adjusted HR (95% CI) were 1.01 (0.98-1.03); 0.98 (0.96-1.01); 0.98 (0.95-1.02); 0.99 (0.97-1.02), respectively. Similarly, non-pleiotropic HDLc and LDLc gene scores showed no association with incident AF: HR (95% CI) = 1.00 (0.97-1.03); 1.01 (0.99-1.04). CONCLUSIONS: In this large cohort study of individuals of European ancestry, gene scores for lipid fractions were not associated with incident AF