556 research outputs found

    Vibration control of wood-polymeric composite structures using piezoelectric transducers

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    Vibration control has been a subject of engineering research for the past few decades. Recently, the use of smart materials-related components for vibration control has become an alternative to traditional vibration control techniques. Vibration control with smart materials have many advantages such as lighter weight, smaller size, flexibility in the structure and lower cost. They are especially suitable where the traditional techniques cannot be applied due to weight and size restriction. The scope of the study is to understand the nature of piezoelectric materials for converting mechanical energy to electrical energy and vice versa. Physical properties of piezoelectric materials for vibration sensing, actuation and dissipation were evaluated. An analytical study of the resistorinductor (R-L) passive piezoelectric vibration shunt control of a cantilever beam was undertaken. The modal and strain analyses were performed by varying the material properties and geometric configurations of the piezoelectric transducer in relation to the structure in order to maximize the mechanical strain produced in the piezoelectric transducer. Numerical modelling of structures was performed and field-coupled with the passive piezoelectric vibration shunt control circuitry. The Finite Element Analysis (FEA) was used for the analysis and optimal design. Experiments with the passive piezoelectric vibration shunt control of beams were also carried out and the results compared to the analytical and computational work described above

    Being a peer support mentor for individuals who have had a lower limb amputation:an interpretative phenomenological analysis

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    Purpose: Although peer support has received research attention within different health related contexts, there is limited research considering individuals who have experienced an amputation. In particular, the peer mentoring role is under-explored. Therefore, this research aimed to explore the experiences of participants delivering peer support interventions to individuals with lower limb loss. Methods: Eight people who acted as peer mentors for people with limb loss took part in semi-structured interviews. Data were analyzed using Interpretative Phenomenological Analysis (IPA). Results: Two overarching themes were identified from the data: “Developing a Helpful Self”, in which the personal value and meaning of being a peer mentor is presented, and “Connecting with Vulnerability”, which addresses the emotional challenges of peer mentoring and the impact of these on wellbeing. Conclusions: Findings suggest positive experiences of providing support, including increased hope, resilience and a sense of belonging and connection to others. However, peer mentors experienced challenges related to uncertainty and doubt about their mentoring abilities and with developing and maintaining resilience in the role. Recommendations include the development of training packages and increased clarity for volunteers of the peer mentor role.Implications for rehabilitation It is important to define clearly the role of a peer mentor and the responsibilities this involves. Peer mentors should be provided with support and training to increase their confidence and ability to act appropriately when encountering distress. It is important to provide transparent guidelines and procedures to support peer mentors to minimize concerns over risk and safety. Feedback regarding how effective the support offered is and how it could be improved should be provided

    Obesity, antenatal depression, diet and gestational weight gain in a population cohort study

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    PURPOSE: The aims of this paper are to examine: (1) the relationship between high pre-pregnancy BMI and antenatal depression; (2) whether BMI and antenatal depression interact to predict diet and gestational weight gain (GWG). METHODS: Data came from the Avon Longitudinal Study of Parents and Children (ALSPAC). Underweight women were excluded. Pre-pregnancy BMI was self-reported and antenatal depression was assessed using the Edinburgh Postnatal Depression Scale at 18 and 32 weeks' gestation to identify persistently elevated depressive symptoms (EPDS>12). Dietary patterns were calculated from food frequency questionnaires at 32 weeks' gestation. GWG was categorised using the USA Institute of Medicine guidelines. RESULTS: This study included 13,314 pregnant women. Obese women had significantly higher odds of antenatal depression than normal weight controls after adjusting for socio-demographics and health behaviours (aOR 1.39, 95%CI 1.05-1.84). Every unit increase in pre-pregnancy BMI was associated with approximately 3% higher odds of antenatal depression (aOR 1.03, 95%CI 1.01-1.05). Antenatal depression was not meaningfully associated with dietary patterns after adjusting for confounders and was not associated with inadequate or excessive GWG. There was no evidence for an interaction of depression and BMI on either diet or GWG. CONCLUSIONS: Healthcare professionals should be aware of the dose-response relationship between high pre-pregnancy BMI and antenatal depression

    Design and rationale of a multi-center, pragmatic, open-label randomized trial of antimicrobial therapy - the study of clinical efficacy of antimicrobial therapy strategy using pragmatic design in Idiopathic Pulmonary Fibrosis (CleanUP-IPF) clinical trial

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    Compelling data have linked disease progression in patients with idiopathic pulmonary fibrosis (IPF) with lung dysbiosis and the resulting dysregulated local and systemic immune response. Moreover, prior therapeutic trials have suggested improved outcomes in these patients treated with either sulfamethoxazole/ trimethoprim or doxycycline. These trials have been limited by methodological concerns. This trial addresses the primary hypothesis that long-term treatment with antimicrobial therapy increases the time-to-event endpoint of respiratory hospitalization or all-cause mortality compared to usual care treatment in patients with IPF. We invoke numerous innovative features to achieve this goal, including: 1) utilizing a pragmatic randomized trial design; 2) collecting targeted biological samples to allow future exploration of 'personalized' therapy; and 3) developing a strong partnership between the NHLBI, a broad range of investigators, industry, and philanthropic organizations. The trial will randomize approximately 500 individuals in a 1:1 ratio to either antimicrobial therapy or usual care. The site principal investigator will declare their preferred initial antimicrobial treatment strategy (trimethoprim 160 mg/ sulfamethoxazole 800 mg twice a day plus folic acid 5 mg daily or doxycycline 100 mg once daily if body weight is < 50 kg or 100 mg twice daily if ≥50 kg) for the participant prior to randomization. Participants randomized to antimicrobial therapy will receive a voucher to help cover the additional prescription drug costs. Additionally, those participants will have 4-5 scheduled blood draws over the initial 24 months of therapy for safety monitoring. Blood sampling for DNA sequencing and genome wide transcriptomics will be collected before therapy. Blood sampling for transcriptomics and oral and fecal swabs for determination of the microbiome communities will be collected before and after study completion. As a pragmatic study, participants in both treatment arms will have limited in-person visits with the enrolling clinical center. Visits are limited to assessments of lung function and other clinical parameters at time points prior to randomization and at months 12, 24, and 36. All participants will be followed until the study completion for the assessment of clinical endpoints related to hospitalization and mortality events. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT02759120

    Project-based learning as a contributing factor to graduates&#039; work readiness

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    This paper explores what work readiness means for two cohorts of graduate engineers, one from a traditional curriculum, the second from a largely project-based curriculum. Professional bodies and employers have defined a set of attributes for engineering graduates so that graduates will be &#039;work ready&#039;. Problem-based learning (PBL) is claimed to be a suitable approach to develop such skills

    Transport of ER Vesicles on Actin Filaments in Neurons by Myosin V

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    Axoplasmic organelles in the giant axon of the squid have been shown to move on both actin filaments and microtubules and to switch between actin filaments and microtubules during fast axonal transport. The objectives of this investigation were to identify the specific classes of axoplasmic organelles that move on actin filaments and the myosin motors involved. We developed a procedure to isolate endoplasmic reticulum (ER) from extruded axoplasm and to reconstitute its movement in vitro. The isolated ER vesicles moved on exogenous actin filaments adsorbed to coverslips in an ATP-dependent manner without the addition of soluble factors. Therefore myosin was tightly bound and not extracted during isolation. These vesicles were identified as smooth ER by use of an antibody to an ER-resident protein, ERcalcistorin/protein disulfide isomerase (EcaSt/PDI). Furthermore, an antibody to squid myosin V was used in immunogold EM studies to show that myosin V localized to these vesicles. The antibody was generated to a squid brain myosin (p196) that was classified as myosin V based on comparisons of amino acid sequences of tryptic peptides of this myosin with those of other known members of the myosin V family. Dual labeling with the squid myosin V antibody and a kinesin heavy chain antibody showed that the two motors colocalized on the same vesicles. Finally, antibody inhibition experiments were performed with two myosin V-specific antibodies to show that myosin V motor activity is required for transport of vesicles on actin filaments in axoplasm. One antibody was made to a peptide in the globular tail domain and the other to the globular head fragment of myosin V. Both antibodies inhibited vesicle transport on actin filaments by greater than 90% compared to controls. These studies provide the first direct evidence that ER vesicles are transported on actin filaments by myosin V. These data confirm the role of actin filaments in fast axonal transport and provide support for the dual filament model of vesicle transport

    Socio-economic status influences the relationship between obesity and antenatal depression: Data from a prospective cohort study

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    Background Obesity has been associated with increased risk of antenatal depression, but little is known about this relationship. This study tested whether socio-economic status (SES) influences the relationship between obesity and antenatal depression. Methods Data were taken from the Screening for Pregnancy Endpoints (SCOPE) cohort. BMI was calculated from measured height and weight at 15±1 weeks' gestation. Underweight women were excluded. SES was indicated by self-reported household income (dichotomised around the median: low SES ≤£45,000; high SES >£45,000). Antenatal depression was defined as scoring ≥13 on the Edinburgh Postnatal Depression Scale at both 15±1 and 20±1 weeks' gestation, to identify persistently elevated symptoms of depression. Results Five thousand five hundred and twenty two women were included in these analyses and 5.5% had persistently elevated antenatal depression symptoms. There was a significant interaction between SES and BMI on the risk of antenatal depression (p=0.042). Among high SES women, obese women had approximately double the odds of antenatal depression than normal weight controls (AOR 2.11, 95%CI 1.16–3.83, p=0.014, adjusted for confounders). Among low SES women there was no association between obesity and antenatal depression. The interaction effect was robust to alternative indicators of SES in sensitivity analyses. Limitations 1) Antenatal depression was assessed with a self-reported screening measure; and 2) potential mediators such as stigma and poor body-image could not be examined. Conclusions Obesity was only associated with increased risk of antenatal depression among high SES women in this sample. Healthcare professionals should be aware that antenatal depression is more common among low SES women, regardless of BMI category
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