637 research outputs found

    Structural Origins of Chiral Second-Order Optical Nonlinearity in Collagen: Amide I Band

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    AbstractThe molecular basis of nonlinear optical (NLO) chiral effects in the amide I region of type I collagen was investigated using sum-frequency generation vibrational spectroscopy; chiral and achiral tensor elements were separated using different input/output beam polarization conditions. Spectra were obtained from native rat tail tendon (RTT) collagen and from cholesteric liquid crystal-like (LC) type I collagen films. Although RTT and LC collagen both possess long-range order, LC collagen lacks the complex hierarchical organization of RTT collagen. Their spectra were compared to assess the role of such organization in NLO chirality. No significant differences were observed between RTT and LC with respect to chiral or achiral spectra. These findings suggest that amide I NLO chiral effects in type I collagen assemblies arise predominantly from the chiral organization of amide chromophores within individual collagen molecules, rather than from supramolecular structures. The study suggests that sum-frequency generation vibrational spectroscopy may be uniquely valuable in exploring fundamental aspects of chiral nonlinearity in complex macromolecular structures

    Developments in mental health service provision: views of service users and carers

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    This paper reports on a study in two NHS Mental Health Trusts in England in 2008-2009. Data were collected from staff, service users and carers to inform service and workforce developments. The findings reported relate to service users and carers and concur with staff views. They relate to modernisation of services, the challenges of a multiplicity of stakeholders and organisations, as well as the need to involve users and carers in developments. The findings resonate with national and local policy with a move away from traditional psychiatric care to integrated person-centred community care with a focus on recovery, rehabilitation and self care

    Multiple myeloma and physical activity: a scoping review

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    Objectives: Multiple myeloma is the second most common haematological cancer. A growing body of literature is emerging that investigates the role physical activity plays in all stages of multiple myeloma (prevention and survivorship) and to date no attempt has been made to collate and understand this literature. Therefore, this scoping review aims to (1) outline what is already known about physical activity in all stages of multiple myeloma (2) map the literature on physical activity and multiple myeloma and (3) identify future directions for research. Design: Scoping Review. Data Sources: Searches were carried out in May 2015. Searches were conducted in PubMed, Web of Science, SPORTdiscus and MEDLINE. Eligibility criteria for selecting studies: To be included studies had to report original data, investigate physical activity per se or physical activity correlates and multiple myeloma or smouldering multiple myeloma. Results: A total of 19 papers received full screening, 5 of these papers were excluded. This review identified three journal articles relating to the role of physical activity in the prevention of multiple myeloma, nine papers were identified in the treatment of multiple myeloma and two on smouldering multiple myeloma. Conclusions: The search identified that the literature surrounding multiple myeloma and physical activity is very limited. We encourage those designing new cohort studies to allow for future assessment of associations between physical activity and onset of multiple myeloma and smouldering multiple myeloma, as well as the potential role that physical activity plays in the progression from smouldering multiple myeloma to multiple myeloma. Second, we encourage the design and investigation of gender and treatment-specific physical activity interventions in patients with multiple myeloma. Finally, we highlight the need for more randomised controlled trials to evaluate the impact of different types, frequencies and intensities of physical activity on various health parameters in multiple myeloma survivors

    Low temperature structural phase transition and incommensurate lattice modulation in the spin gap compound BaCuSi2O6

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    Results of high resolution x-ray diffraction experiments are presented for single crystals of the spin gap compound BaCuSi2_2O6_6 in the temperature range from 16 to 300 K. The data show clear evidence of a transition from the room temperature tetragonal phase into an incommensurately modulated orthorhombic structure below ∼\sim100 K. This lattice modulation is characterized by a resolution limited wave vector {\bf q}IC_{IC}=(0,∼\sim0.13,0) and its 2nd^{nd} and 3rd^{rd} harmonics. The phase transition is first order and exhibits considerable hysteresis. This observation implies that the spin Hamiltonian representing the system is more complex than originally thought.Comment: 4 pages, 4 figure

    Efficacy of Prehabilitation Including Exercise on Postoperative Outcomes Following Abdominal Cancer Surgery: A Systematic Review and Meta-Analysis

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    OBJECTIVE: This systematic review set out to identify, evaluate and synthesise the evidence examining the effect of prehabilitation including exercise on postoperative outcomes following abdominal cancer surgery. METHODS: Five electronic databases (MEDLINE 1946-2020, EMBASE 1947-2020, CINAHL 1937-2020, PEDro 1999-2020, and Cochrane Central Registry of Controlled Trials 1991-2020) were systematically searched (until August 2020) for randomised controlled trials (RCTs) that investigated the effects of prehabilitation interventions in patients undergoing abdominal cancer surgery. This review included any form of prehabilitation either unimodal or multimodal that included whole body and/or respiratory exercises as a stand-alone intervention or in addition to other prehabilitation interventions (such as nutrition and psychology) compared to standard care. RESULTS: Twenty-two studies were included in the systematic review and 21 studies in the meta-analysis. There was moderate quality of evidence that multimodal prehabilitation improves pre-operative functional capacity as measured by 6 min walk distance (Mean difference [MD] 33.09 metres, 95% CI 17.69–48.50; p = <0.01) but improvement in cardiorespiratory fitness such as preoperative oxygen consumption at peak exercise (VO2 peak; MD 1.74 mL/kg/min, 95% CI −0.03–3.50; p = 0.05) and anaerobic threshold (AT; MD 1.21 mL/kg/min, 95% CI −0.34–2.76; p = 0.13) were not significant. A reduction in hospital length of stay (MD 3.68 days, 95% CI 0.92–6.44; p = 0.009) was observed but no effect was observed for postoperative complications (Odds Ratio [OR] 0.81, 95% CI 0.55–1.18; p = 0.27), pulmonary complications (OR 0.53, 95% CI 0.28–1.01; p = 0.05), hospital re-admission (OR 1.07, 95% CI 0.61–1.90; p = 0.81) or postoperative mortality (OR 0.95, 95% CI 0.43–2.09, p = 0.90). CONCLUSION: Multimodal prehabilitation improves preoperative functional capacity with reduction in hospital length of stay. This supports the need for ongoing research on innovative cost-effective prehabilitation approaches, research within large multicentre studies to verify this effect and to explore implementation strategies within clinical practise

    Use of an 'adapted Zelen' design in a randomised controlled trial of a physiotherapist-led exercise intervention in patients with myeloma

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    Quantitative analysis methods for studying fenestrations in liver sinusoidal endothelial cells. A comparative study

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    Liver Sinusoidal Endothelial Cells (LSEC) line the hepatic vasculature providing blood filtration via transmembrane nanopores called fenestrations. These structures are 50−300 nm in diameter, which is below the resolution limit of a conventional light microscopy. To date, there is no standardized method of fenestration image analysis. With this study, we provide and compare three different approaches: manual measurements, a semi-automatic (threshold-based) method, and an automatic method based on user-friendly open source machine learning software. Images were obtained using three super resolution techniques – atomic force microscopy (AFM), scanning electron microscopy (SEM), and structured illumination microscopy (SIM). Parameters describing fenestrations such as diameter, area, roundness, frequency, and porosity were measured. Finally, we studied the user bias by comparison of the data obtained by five different users applying provided analysis methods

    The adapted Zelen was a feasible design to trial exercise in myeloma survivors

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    OBJECTIVE: We utilised a method rarely seen in cancer behavioural trials to explore methods of overcoming difficulties often seen in randomised controlled trials. We report our experiences of the adapted-Zelen design, so that other researchers can consider this approach for behavioural trials. STUDY DESIGN: & Setting:The adapted-Zelen design was used to explore the effects of exercise on multiple myeloma patients fatigue, quality of life and physical outcomes. All participants consented to an observational cohort study of lifestyle factors, but were unaware of subsequent randomisation to remain in cohort only group or be offered an exercise intervention requiring second consent. RESULTS: Due to lower than expected uptake rate to the exercise offered group (57%), the length of recruitment increased from 24 to 29 months to ensure power was reached. At enrolment patients were unaware of the potential increased commitment and as a result 62% of participants allocated to the intervention declined due to the extra time/travel commitment required. This emulates clinical settings and suggests improvements in intervention delivery are required. Dropout rates from the cohort only group were similar to designs that provide the control with the intervention. Our results from the main study do not suggest contamination occurred despite some anecdotal evidence. CONCLUSION: Future use of this design warrants careful consideration of the study resources and recruitment time frames required but holds potential value in reducing contamination, control group dissatisfaction and resulting drop out. Adapted-Zelen design reduces selection bias and therefore gives clinicians a better understanding of acceptability in clinical settings. Future studies should evaluate control group experiences of the design and formally record contamination throughout the study to confirm its acceptability
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