472 research outputs found

    Investigation of hollow cylindrical metal terahertz waveguides suitable for cryogenic environments

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    The field of terahertz (THz) waveguides continues to grow rapidly, with many being tailored to suit the specific demands of a particular final application. Here, we explore waveguides capable of enabling efficient and accurate power delivery within cryogenic environments (< 4 K). The performance of extruded hollow cylindrical metal waveguides made of un-annealed and annealed copper, as well as stainless steel, have been investigated for bore diameters between 1.75 - 4.6 mm, and at frequencies of 2.0, 2.85 and 3.4 THz, provided by a suitable selection of THz quantum cascade lasers. The annealed copper resulted in the lowest transmission losses, < 3 dB/m for a 4.6 mm diameter waveguide, along with 90° bending losses as low as ~2 dB for a bend radius of 15.9 mm. The observed trends in losses were subsequently analyzed and related to measured inner surface roughness parameters. These results provide a foundation for the development of a wide array of demanding low-temperature THz applications, and enabling the study of fundamental physics.Engineering and Physical Sciences Research Council (Grant No. EP/J017671/1, Coherent Terahertz Systems)

    Filamin A (FLNA) mutation—A newcomer to the childhood interstitial lung disease (ChILD) classification

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    AIM: Interstitial lung disease (ILD) in infants represents a rare and heterogenous group of disorders, distinct from those occurring in adults. In recent years a new entity within this category is being recognized, namely filamin A (FLNA) mutation related lung disease. Our aims are to describe the clinical and radiological course of patients with this disease entity to aid clinicians in the prognostic counseling and management of similar patients they may encounter. METHOD: A retrospective case note review was conducted of all patients treated at our institution (a specialist tertiary referral childrens’ center) for genetically confirmed FLNA mutation related lung disease. The clinical presentation, evolution, management and radiological features were recorded and a medical literature review of Medline indexed articles was conducted. RESULTS: We present a case series of four patients with interstitial lung disease and genetically confirmed abnormalities within the FLNA gene. Their imaging findings all reveal a pattern of predominantly upper lobe overinflation, coarse pulmonary lobular septal thickening and diffuse patchy atelectasis. The clinical outcomes of our patients have been variable ranging from infant death, lobar resection and need for supplemental oxygen and bronchodilators. CONCLUSION: The progressive nature of the pulmonary aspect of this disorder and need for early aggressive supportive treatment make identification crucial to patient management and prognostic counseling

    The multiple sex chromosomes of platypus and echidna are not completely identical and several share homology with the avian Z.

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    BACKGROUND: Sex-determining systems have evolved independently in vertebrates. Placental mammals and marsupials have an XY system, birds have a ZW system. Reptiles and amphibians have different systems, including temperature-dependent sex determination, and XY and ZW systems that differ in origin from birds and placental mammals. Monotremes diverged early in mammalian evolution, just after the mammalian clade diverged from the sauropsid clade. Our previous studies showed that male platypus has five X and five Y chromosomes, no SRY, and DMRT1 on an X chromosome. In order to investigate monotreme sex chromosome evolution, we performed a comparative study of platypus and echidna by chromosome painting and comparative gene mapping. RESULTS: Chromosome painting reveals a meiotic chain of nine sex chromosomes in the male echidna and establishes their order in the chain. Two of those differ from those in the platypus, three of the platypus sex chromosomes differ from those of the echidna and the order of several chromosomes is rearranged. Comparative gene mapping shows that, in addition to bird autosome regions, regions of bird Z chromosomes are homologous to regions in four platypus X chromosomes, that is, X1, X2, X3, X5, and in chromosome Y1. CONCLUSION: Monotreme sex chromosomes are easiest to explain on the hypothesis that autosomes were added sequentially to the translocation chain, with the final additions after platypus and echidna divergence. Genome sequencing and contig anchoring show no homology yet between platypus and therian Xs; thus, monotremes have a unique XY sex chromosome system that shares some homology with the avian Z.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

    Transcriptomics reveal an integrative role for maternal thyroid hormones during zebrafish embryogenesis

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    Thyroid hormones (THs) are essential for embryonic brain development but the genetic mechanisms involved in the action of maternal THs (MTHs) are still largely unknown. As the basis for understanding the underlying genetic mechanisms of MTHs regulation we used an established zebrafish monocarboxylic acid transporter 8 (MCT8) knock-down model and characterised the transcriptome in 25hpf zebrafish embryos. Subsequent mapping of differentially expressed genes using Reactome pathway analysis together with in situ expression analysis and immunohistochemistry revealed the genetic networks and cells under MTHs regulation during zebrafish embryogenesis. We found 4,343 differentially expressed genes and the Reactome pathway analysis revealed that TH is involved in 1681 of these pathways. MTHs regulated the expression of core developmental pathways, such as NOTCH and WNT in a cell specific context. The cellular distribution of neural MTH-target genes demonstrated their cell specific action on neural stem cells and differentiated neuron classes. Taken together our data show that MTHs have a role in zebrafish neurogenesis and suggest they may be involved in cross talk between key pathways in neural development. Given that the observed MCT8 zebrafish knockdown phenotype resembles the symptoms in human patients with Allan-Herndon-Dudley syndrome our data open a window into understanding the genetics of this human congenital condition.Portuguese Fundacao para Ciencia e Tecnologia (FCT) [PTDC/EXPL/MARBIO/0430/2013]; CCMAR FCT Plurianual financing [UID/Multi/04326/2013]; FCT [SFRH/BD/111226/2015, SFRH/BD/108842/2015, SFRH/BPD/89889/2012]; FCT-IF Starting Grant [IF/01274/2014]info:eu-repo/semantics/publishedVersio

    Design of the New Life(style) study: a randomised controlled trial to optimise maternal weight development during pregnancy. [ISRCTN85313483]

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    BACKGROUND: Preventing excessive weight gain during pregnancy is potentially important in the prevention of overweight and obesity among women of childbearing age. However, few intervention studies aiming at weight management during pregnancy have been performed and most of these interventions were not as successful as expected. In this paper the design of the New Life(style) study is described as well as the content of the individually tailored intervention program, which focuses on controlling weight development during pregnancy. METHODS: The effectiveness of the New Life(style) intervention program versus usual care by midwives is evaluated in a randomised controlled trial. Women who expect their first child and visit one of the participating midwifery practices are included. The intervention is standardised in a protocol and executed by trained counsellors with the women who are randomised in the intervention group. During 5 sessions – at 18, 22, 30 and 36 weeks of pregnancy and at 8 weeks postpartum – individual weight gain is discussed in relation to weight gain guidelines for pregnant women of the American Institute of Medicine. Counsellors coach the women to maintain or optimise a healthy lifestyle, in a period of drastic physical and mental changes. Data is collected at 15, 25, 35 weeks of pregnancy and at 6, 26, and 52 weeks after delivery. Primary outcome measures are body weight, BMI, and skinfold thickness. Secondary outcome measures include physical activity, nutrition and blood levels of factors that are associated with energy homeostasis. DISCUSSION: Results of the current RCT will improve the knowledge of determinants of weight gain during pregnancy, weight retention after childbirth and of the effectiveness of the intervention program that is described. Caregivers and researchers in the field of health promotion are offered more insight in specific elements of the New Life(style) intervention program

    Attitudes and perceptions of Australian pharmacy students towards Complementary and Alternative Medicine – a pilot study

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    <p>Abstract</p> <p>Background</p> <p>With the increased usage of CAM worldwide comes the demand for its integration into health professional education. However, the incorporation of CAM into health professional curricula is handled quite differently by different institutions and countries. Furthermore, the evaluation of CAM curricula is complicated because students' ability to learn about CAM may be influenced by factors such as student's prior knowledge and motivation, together with the perceptions and attitudes of clinical preceptors.</p> <p>The study aimed to describe the attitudes, perceptions and beliefs of second, third and fourth year pharmacy students towards complementary and alternative medicine (CAM) and to explore factors that might affect attitudes such as learning, preceptors and placements.</p> <p>Methods</p> <p>Pharmacy students from a University in South East Queensland, Australia participated in the study. The study consisted of a cross-sectional survey (n = 110) and semi-structured interviews (n = 9).</p> <p>Results</p> <p>The overall response rate for the survey was 75%, namely 50% (36/72) for second year, 77.3% (34/44) for third year and 97.6% (40/41) for fourth year students. Overall, 95.5% of pharmacy students believe that pharmacists should be able to advise patients about CAM and most (93.7%) have used CAM prior to course enrolment. Students' attitudes to CAM are influenced by the use of CAM by family, friends and self, CAM training, lecturers and to a lesser degree by preceptors. The majority of pharmacy students (89.2%) perceive education about CAM as a core and integral part of their professional degree and favour it over an additional postgraduate degree. However, they see a greater need for education in complementary medicines (such as herbal medicines, vitamins and minerals) than for education in complementary therapies (such as acupuncture, meditation and bio-magnetism). Knowledge and educational input rationalised rather than marginalised students' attitudes towards CAM.</p> <p>Conclusion</p> <p>Pharmacy students perceive education about CAM as a core and integral part of their professional degree. Students' attitudes towards CAM can be influenced by learning, lecturers, preceptors and practice experience. The content and focus of CAM education has to be further investigated and tailored to meet the professional needs of our future health professionals.</p

    'Sink or swim': an evaluation of the clinical characteristics of individuals with high bone mass.

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    SUMMARY: High bone mineral density on routine dual energy X-ray absorptiometry (DXA) may indicate an underlying skeletal dysplasia. Two hundred fifty-eight individuals with unexplained high bone mass (HBM), 236 relatives (41% with HBM) and 58 spouses were studied. Cases could not float, had mandible enlargement, extra bone, broad frames, larger shoe sizes and increased body mass index (BMI). HBM cases may harbour an underlying genetic disorder. INTRODUCTION: High bone mineral density is a sporadic incidental finding on routine DXA scanning of apparently asymptomatic individuals. Such individuals may have an underlying skeletal dysplasia, as seen in LRP5 mutations. We aimed to characterize unexplained HBM and determine the potential for an underlying skeletal dysplasia. METHODS: Two hundred fifty-eight individuals with unexplained HBM (defined as L1 Z-score ≥ +3.2 plus total hip Z-score ≥ +1.2, or total hip Z-score ≥ +3.2) were recruited from 15 UK centres, by screening 335,115 DXA scans. Unexplained HBM affected 0.181% of DXA scans. Next 236 relatives were recruited of whom 94 (41%) had HBM (defined as L1 Z-score + total hip Z-score ≥ +3.2). Fifty-eight spouses were also recruited together with the unaffected relatives as controls. Phenotypes of cases and controls, obtained from clinical assessment, were compared using random-effects linear and logistic regression models, clustered by family, adjusted for confounders, including age and sex. RESULTS: Individuals with unexplained HBM had an excess of sinking when swimming (7.11 [3.65, 13.84], p < 0.001; adjusted odds ratio with 95% confidence interval shown), mandible enlargement (4.16 [2.34, 7.39], p < 0.001), extra bone at tendon/ligament insertions (2.07 [1.13, 3.78], p = 0.018) and broad frame (3.55 [2.12, 5.95], p < 0.001). HBM cases also had a larger shoe size (mean difference 0.4 [0.1, 0.7] UK sizes, p = 0.009) and increased BMI (mean difference 2.2 [1.3, 3.1] kg/m(2), p < 0.001). CONCLUSION: Individuals with unexplained HBM have an excess of clinical characteristics associated with skeletal dysplasia and their relatives are commonly affected, suggesting many may harbour an underlying genetic disorder affecting bone mass

    Cost-effectiveness of collaborative care including PST and an antidepressant treatment algorithm for the treatment of major depressive disorder in primary care; a randomised clinical trial

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    BACKGROUND: Depressive disorder is currently one of the most burdensome disorders worldwide. Evidence-based treatments for depressive disorder are already available, but these are used insufficiently, and with less positive results than possible. Earlier research in the USA has shown good results in the treatment of depressive disorder based on a collaborative care approach with Problem Solving Treatment and an antidepressant treatment algorithm, and research in the UK has also shown good results with Problem Solving Treatment. These treatment strategies may also work very well in the Netherlands too, even though health care systems differ between countries. METHODS/DESIGN: This study is a two-armed randomised clinical trial, with randomization on patient-level. The aim of the trial is to evaluate the treatment of depressive disorder in primary care in the Netherlands by means of an adapted collaborative care framework, including contracting and adherence-improving strategies, combined with Problem Solving Treatment and antidepressant medication according to a treatment algorithm. Forty general practices will be randomised to either the intervention group or the control group. Included will be patients who are diagnosed with moderate to severe depression, based on DSM-IV criteria, and stratified according to comorbid chronic physical illness. Patients in the intervention group will receive treatment based on the collaborative care approach, and patients in the control group will receive care as usual. Baseline measurements and follow up measures (3, 6, 9 and 12 months) are assessed using questionnaires and an interview. The primary outcome measure is severity of depressive symptoms, according to the PHQ9. Secondary outcome measures are remission as measured with the PHQ9 and the IDS-SR, and cost-effectiveness measured with the TiC-P, the EQ-5D and the SF-36. DISCUSSION: In this study, an American model to enhance care for patients with a depressive disorder, the collaborative care model, will be evaluated for effectiveness in the primary care setting. If effective across the Atlantic and across different health care systems, it is also likely to be an effective strategy to implement in the treatment of major depressive disorder in the Netherlands

    The effectiveness of adding cognitive behavioural therapy aimed at changing lifestyle to managed diabetes care for patients with type 2 diabetes: design of a randomised controlled trial

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    <p>Abstract</p> <p>Background</p> <p>In patients with type 2 diabetes, the risk for cardiovascular disease is substantial. To achieve a more favourable risk profile, lifestyle changes on diet, physical activity and smoking status are needed. This will involve changes in behaviour, which is difficult to achieve. Cognitive behavioural therapies focussing on self-management have been shown to be effective. We have developed an intervention combining techniques of Motivational Interviewing (MI) and Problem Solving Treatment (PST). The aim of our study is to investigate if adding a combined behavioural intervention to managed care, is effective in achieving changes in lifestyle and cardiovascular risk profile.</p> <p>Methods</p> <p>Patients with type 2 diabetes will be selected from general practices (n = 13), who are participating in a managed diabetes care system. Patients will be randomised into an intervention group receiving cognitive behaviour therapy (CBT) in addition to managed care, and a control group that will receive managed care only. The CBT consists of three to six individual sessions of 30 minutes to increase the patient's motivation, by using principles of MI, and ability to change their lifestyle, by using PST. The first session will start with a risk assessment of diabetes complications that will be used to focus the intervention.</p> <p>The primary outcome measure is the difference between intervention and control group in change in cardiovascular risk score. For this purpose blood pressure, HbA<sub>1c</sub>, total and HDL-cholesterol and smoking status will be assessed. Secondary outcome measures are quality of life, patient satisfaction, physical activity, eating behaviour, smoking status, depression and determinants of behaviour change. Differences between changes in the two groups will be analysed according to the intention-to-treat principle, with 95% confidence intervals. The power calculation is based on the risk for cardiovascular disease and we calculated that 97 patients should be included in every group.</p> <p>Discussion</p> <p>Cognitive behavioural therapy may improve self-management and thus strengthen managed diabetes care. This should result in changes in lifestyle and cardiovascular risk profile. In addition, we also expect an improvement of quality of life and patient satisfaction.</p> <p>Trial registration</p> <p>Current Controlled Trials ISRCTN12666286</p
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