98 research outputs found

    A Comparative Study of Three Different Chemical Vapor Deposition Techniques of Carbon Nanotube Growth on Diamond Films

    Get PDF
    This paper compares between the methods of growing carbon nanotubes (CNTs) on diamond substrates and evaluates the quality of the CNTs and the interfacial strength. One potential application for these materials is a heat sink/spreader for high-power electronic devices. The CNTs and diamond substrates have a significantly higher specific thermal conductivity than traditional heat sink/spreader materials making them good replacement candidates. Only limited research has been performed on these CNT/diamond structures and their suitability of different growth methods. This study investigates three potential chemical vapor deposition (CVD) techniques for growing CNTs on diamond: thermal CVD (T-CVD), microwave plasma-enhanced CVD (MPE-CVD), and floating catalyst thermal CVD (FCT-CVD). Scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (TEM) were used to analyze the morphology and topology of the CNTs. Raman spectroscopy was used to assess the quality of the CNTs by determining the ID/IG peak intensity ratios. Additionally, the CNT/diamond samples were sonicated for qualitative comparisons of the durability of the CNT forests. T-CVD provided the largest diameter tubes, with catalysts residing mainly at the CNT/diamond interface. The MPE-CVD process yielded non uniform defective CNTs, and FCT-CVD resulted in the smallest diameter CNTs with catalyst particles imbedded throughout the length of the nanotubes

    Challenges faced by young mothers with a care history and views of stakeholders about the potential for Group Family Nurse Partnership (gFNP) to support their needs

    Get PDF
    Women with experience of being ‘looked after’ are more likely than their peers to become young mothers. There has been limited research investigating support for their needs. This study, embedded in a randomised trial of Group Family Nurse Partnership (gFNP), involved interviews with young mothers with care experience, Family Nurses delivering group gFNP, and health and social care professionals. This first qualitative study to explore the views of these varied stakeholders found consensus regarding young mothers’ social isolation and lack of trusting relationships but diversity in views about the potential of gFNP to meet their needs

    Results of the First Steps study: a randomised controlled trial and economic evaluation of the Group Family Nurse Partnership (gFNP) programme compared with usual care in improving outcomes for high-risk mothers and their children and preventing abuse

    Get PDF
    Background: Family Nurse Partnership (FNP) is a home-based nurse home-visiting programme to support vulnerable parents. Group Family Nurse Partnership (gFNP) has similar aims and materials and was demonstrated to be feasible in implementation evaluations. Objectives: To determine whether or not gFNP, compared with usual care, could reduce risk factors for maltreatment in a vulnerable group and be cost-effective. Design: A multisite randomised controlled parallel-group trial and prospective economic evaluation, with eligible women allocated (minimised by site and maternal age group) to gFNP or usual care. Setting: Community locations in the UK. Participants: Expectant mothers aged < 20 years with one or more previous live births, or expectant mothers aged 20–24 years with no previous live births and with low educational qualifications (defined as General Certificate of Education at grade C or higher in neither mathematics nor English language or, if they had both, no more than four General Certificates of Education at grade C or higher). Intervention: Forty-four sessions of gFNP (14 during pregnancy and 30 in the first 12 months after birth) were offered to groups of between 8 and 12 women with similar expected delivery dates (the difference between the earliest and latest expected delivery date ranged from 8 to 10 weeks depending on the group) by two family nurses (FNs), one of whom had notified her intention to practise as a midwife. Main outcome measures: Parenting was assessed by a self-report measure of parenting opinions, the Adult Adolescent Parenting Inventory Version 2 (AAPI-2), and an objective measure of maternal sensitivity, the CARE-Index. Cost-effectiveness was primarily expressed in terms of incremental cost per quality-adjusted life-year (QALY) gained. Data sources: Interviews with participants at baseline and when infants were aged 2, 6 and 12 months. Cost information from nurse weekly logs and other service delivery data. Results: In total, 166 women were enrolled (99 to the intervention group and 67 to the control group). Adjusting for site and maternal age group, the intention-to-treat analysis found no effect of gFNP on either of the primary outcomes. AAPI-2 total was 7.5/10 [standard error (SE) 0.1] in both arms [difference also adjusted for baseline 0.08, 95% confidence interval (CI) –0.15 to 0.28; p = 0.50]. CARE-Index maternal sensitivity mean: intervention 4.0 (SE 0.3); control 4.7 (SE 0.4) (difference –0.76, 95% CI –1.67 to 0.13; p = 0.21). The sensitivity analyses supported the primary analyses. The probability that the gFNP intervention was cost-effective based on the QALY measure did not exceed 3%. However, in terms of change in AAPI-2 score (baseline to 12 months), the probability that gFNP was cost-effective reached 25.1%. A separate discrete choice experiment highlighted the value placed by both pregnant women and members of the general population on non-health outcomes that were not included in the QALY metric. Limitations: Slow recruitment resulted in smaller than ideal group sizes. In some cases, few or no sessions took place owing to low initial group size, and small groups may have contributed to attrition from the intervention. Exposure to gFNP sessions was below maximum for most group members, with only 58 of the 97 intervention participants receiving any sessions; FNs were experienced with FNP but were mainly new to delivering gFNP. Conclusions: The trial does not support the delivery of gFNP as a means of reducing the risk of child abuse or neglect in this population. Future work: A randomised controlled trial with modified eligibility to enable first-time mothers aged < 20 years to be included, and a modified recruitment strategy to enable faster identification of potential participants from antenatal medical records

    Evaluating a Measure of Social Health Derived from Two Mental Health Recovery Measures: The California Quality of Life (CA-QOL) and Mental Health Statistics Improvement Program Consumer Survey (MHSIP)

    Get PDF
    Social health is important to measure when assessing outcomes in community mental health. Our objective was to validate social health scales using items from two broader commonly used measures that assess mental health outcomes. Participants were 609 adults receiving psychological treatment services. Items were identified from the California Quality of Life (CA-QOL) and Mental Health Statistics Improvement Program (MHSIP) outcome measures by their conceptual correspondence with social health and compared to the Social Functioning Questionnaire (SFQ) using correlational analyses. Pearson correlations for the identified CA-QOL and MSHIP items with the SFQ ranged from .42 to .62, and the identified scale scores produced Pearson correlation coefficients of .56, .70, and, .70 with the SFQ. Concurrent validity with social health was supported for the identified scales. The current inclusion of these assessment tools allows community mental health programs to include social health in their assessments

    Functionalized carboxyl nanoparticles enhance mucus dispersion and hydration

    Get PDF
    Luminal accumulation of viscous, poorly hydrated, and less transportable mucus has been associated with altered mucus rheology and reduced mucociliary clearance. These symptoms are some of the cardinal clinical manifestations found throughout major respiratory diseases as well as gastrointestinal and digestive disorders. Applications of current mucolytics may yield short-term improvements but are continuously challenged by undesirable side-effects. While nanoparticles (NPs) can interact with mucin polymers, whether functionalized NPs can rectify mucus rheology is unknown. Herein, we report that carboxyl-functionalized NPs (24 nm and 120 nm) dramatically reduced mucin gel size and accelerated mucin matrix hydration rate (diffusivity). Our results suggest that carboxyl-functionalized NPs disperse mucin gels possibly by enhancing network hydration. This report highlights the prospective usages of carboxyl-functionalized NPs as a novel mucus dispersant or mucolytic agent in adjusting mucus rheological properties and improving mucociliary transport to relieve clinical symptoms of patients suffering from relevant diseases

    IGSF10 mutations dysregulate gonadotropin-releasing hormone neuronal migration resulting in delayed puberty

    Get PDF
    Early or late pubertal onset affects up to 5% of adolescents and is associated with adverse health and psychosocial outcomes. Self-limited delayed puberty (DP) segregates predominantly in an autosomal dominant pattern, but the underlying genetic background is unknown. Using exome and candidate gene sequencing, we have identified rare mutations in IGSF10 in 6 unrelated families, which resulted in intracellular retention with failure in the secretion of mutant proteins. IGSF10 mRNA was strongly expressed in embryonic nasal mesenchyme, during gonadotropin-releasing hormone (GnRH) neuronal migration to the hypothalamus. IGSF10 knockdown caused a reduced migration of immature GnRH neurons invitro, and perturbed migration andextension of GnRH neurons in a gnrh3:EGFP zebrafish model. Additionally, loss-of-function mutations in IGSF10 were identified in hypothalamic amenorrhea patients. Our evidence strongly suggests that mutations in IGSF10 cause DP in humans, and points to a common genetic basis for conditions of functional hypogonadotropic hypogonadism (HH). While dysregulation of GnRH neuronal migration is known to cause permanent HH, this is the first time that this has been demonstrated as a causal mechanism in DP. Synopsis Self-limited delayed puberty (DP) has strong familial inheritance, but the underlying genetic determinants are unknown. IGSF10 deficiency is found to affect embryonic GnRH neuronal migration and results in DP in humans. Pathogenic mutations in IGSF10 are found in patients with self-limited delayed puberty. IGSF10 is a gene of previously unclear function with no known human mutations. IGSF10 is expressed within the nasal mesenchyme during fetal development, in a pattern similar to known chemokines that direct migrational GnRH neurons to the hypothalamus. Knockdown of IGSF10 led to a reduced migration of GnRH neurons invitro and in a transgenic zebrafish model. IGSF10 loss-of-function mutations were also identified in patients with hypothalamic amenorrhea, suggesting an overlapping genetic and mechanistic basis between different types of functional hypogonadotropic hypogonadism, including DP and hypothalamic amenorrhea.Peer reviewe

    100,000 Genomes Pilot on Rare-Disease Diagnosis in Health Care — Preliminary Report

    Get PDF
    BACKGROUND: The U.K. 100,000 Genomes Project is in the process of investigating the role of genome sequencing in patients with undiagnosed rare diseases after usual care and the alignment of this research with health care implementation in the U.K. National Health Service. Other parts of this project focus on patients with cancer and infection. METHODS: We conducted a pilot study involving 4660 participants from 2183 families, among whom 161 disorders covering a broad spectrum of rare diseases were present. We collected data on clinical features with the use of Human Phenotype Ontology terms, undertook genome sequencing, applied automated variant prioritization on the basis of applied virtual gene panels and phenotypes, and identified novel pathogenic variants through research analysis. RESULTS: Diagnostic yields varied among family structures and were highest in family trios (both parents and a proband) and families with larger pedigrees. Diagnostic yields were much higher for disorders likely to have a monogenic cause (35%) than for disorders likely to have a complex cause (11%). Diagnostic yields for intellectual disability, hearing disorders, and vision disorders ranged from 40 to 55%. We made genetic diagnoses in 25% of the probands. A total of 14% of the diagnoses were made by means of the combination of research and automated approaches, which was critical for cases in which we found etiologic noncoding, structural, and mitochondrial genome variants and coding variants poorly covered by exome sequencing. Cohortwide burden testing across 57,000 genomes enabled the discovery of three new disease genes and 19 new associations. Of the genetic diagnoses that we made, 25% had immediate ramifications for clinical decision making for the patients or their relatives. CONCLUSIONS: Our pilot study of genome sequencing in a national health care system showed an increase in diagnostic yield across a range of rare diseases. (Funded by the National Institute for Health Research and others.)

    CMS physics technical design report : Addendum on high density QCD with heavy ions

    Get PDF
    Peer reviewe

    Good to be bad : should we be worried by the sharing economy?

    Get PDF
    We develop the notion of a legitimacy tipping point to demonstrate how informal economy practices are being utilized by innovative sharing economy ventures to gain a competitive advantage that is subsequently leveraged to reconfigure formal institutional arrangements. Companies who are able to scale rapidly can afford to contravene regulations, provided they have public support. When they reach a certain size, in terms of investment and customer numbers, regulators are forced into a reactive position where novel business models are legitimized. This raises an important question for regulators and entrepreneurs as to whether subverting business regulation is being viewed as a viable source of competitive advantage by scaling firms

    Physiological and Psychological Challenges of Increasing Physical Activity and Exercise in Patients at Risk of Diabetic Foot Ulcers: A Critical Review.

    Get PDF
    Obesity and a sedentary lifestyle are common challenges among individuals at risk of diabetic foot ulcers (DFUs). While substantial research exists on physical activity interventions in adults with diabetes, those at greatest risk for foot ulceration were often excluded or not well-represented. Both at-risk patients and their clinicians may be hesitant to increase physical activity due to their perception of DFU risks. Physical activity is not contraindicated for those at risk of DFU, yet patients at risk present with unique barriers to initiating increases in physical activity. This review focuses upon the physiological and psychological challenges of increasing physical activity and exercise in patients at risk of DFUs. Offloading, diabetic peripheral neuropathy, depression, pain, self-efficacy and social support, DFU risk-specific beliefs and emotions, and research to date on exercise interventions in this population are all discussed. Additionally, recommendations for implementing and researching physical activity interventions for individuals at risk for DFU are provided
    corecore