747 research outputs found
Stereospecific four-bond phosphorus-phosphorus spin couplings in phosphazenyl-phosphazenes
Four-bond phosphorus-phosphorus coupling constants have been measured from the 31P NMR spectra of phosphazenylcyclophosphazenes. Their magnitude appears to be related to the conformation adopted by the phosphazenyl-group relative to the phosphazene ring
Temperature, Stress, and Corrosive Sensing Apparatus Utilizing Harmonic Response of Magnetically Soft Sensor Element (s)
A temperature sensing apparatus including a sensor element made of a magnetically soft material operatively arranged within a first and second time-varying interrogation magnetic field, the first time-varying magnetic field being generated at a frequency higher than that for the second magnetic field. A receiver, remote from the sensor element, is engaged to measure intensity of electromagnetic emissions from the sensor element to identify a relative maximum amplitude value for each of a plurality of higher-order harmonic frequency amplitudes so measured. A unit then determines a value for temperature (or other parameter of interst) using the relative maximum harmonic amplitude values identified. In other aspects of the invention, the focus is on an apparatus and technique for determining a value for of stress condition of a solid analyte and for determining a value for corrosion, using the relative maximum harmonic amplitude values identified. A magnetically hard element supporting a biasing field adjacent the magnetically soft sensor element can be included
Analysis of endometrial blood flow with color Doppler energy in predicting outcome in GnRH antagonist down regulated ICSI/IVF cycles: a prospective cohort study setting
Background: The study was conducted to assess the association between endometrial blood flow pattern assessed with colour Doppler around the day of HCG administration and IVF outcome following GnRH antagonist down regulated cycles.Methods: It was a prospective, cohort study. Total of sixty-eight patients undergoing IVF-ET/ICSI were recruited in the study. All the patients underwent controlled ovarian stimulation with a step-up protocol, and GnRH antagonists were used for down-regulation. Transvaginal ultrasound measurements of all patients were performed on the day of HCG injection. A 6.5 MHz pulsed Doppler system was used for blood flow analysis. Bilateral uterine arteries, pulsatility index and resistance index were calculated along with uterine artery peak systolic velocity on both sides. Endometrial blood flow was analysed by detecting flow in the intra-endometrial or the adjacent sub-endometrial regions.Results: Baseline FSH in pregnant group was lower (6.29) than non-pregnant group (7.36). The overall pregnancy rate was 45.6% (n=31) and the ongoing pregnancy rate was 41.1% (n=28). Total of 57 patients out of 68 patients had both good endometrial and sub-endometrial blood flow. The overall pregnancy rate in this group was 47.3%. Similarly, in patients who had minimal endometrial and sub-endometrial blood flow the pregnancy rate was 37.5%. There was no significant correlation between pregnancy outcomes and the color flow Doppler parameters such as average uterine PI, average uterine RI and right/left uterine peak systolic velocity.Conclusion: Uterine artery PI, RI and PSV has no role in predicting endometrial receptivity and thus pregnancy outcome in IVF-ET cycle, however those patient with good endometrial and sub-endometrial flow have higher pregnancy rate than those with minimal flow rate
The relationship between hormone replacement therapy (HRT) and memory performance in women: Influences of HRT type and APOE E4 allele status
Cryopreservation of Human Adipose Tissues and Adipose-Derived Stem Cells with DMSO and/or Trehalose: A Systematic Review.
Adipose tissue senescence is implicated as a major player in obesity- and ageing-related disorders. There is a growing body of research studying relevant mechanisms in age-related diseases, as well as the use of adipose-derived stem cells in regenerative medicine. The cell banking of tissue by utilising cryopreservation would allow for much greater flexibility of use. Dimethyl sulfoxide (DMSO) is the most commonly used cryopreservative agent but is toxic to cells. Trehalose is a sugar synthesised by lower organisms to withstand extreme cold and drought that has been trialled as a cryopreservative agent. To examine the efficacy of trehalose in the cryopreservation of human adipose tissue, we conducted a systematic review of studies that used trehalose for the cryopreservation of human adipose tissues and adipose-derived stem cells. Thirteen articles, including fourteen studies, were included in the final review. All seven studies that examined DMSO and trehalose showed that they could be combined effectively to cryopreserve adipocytes. Although studies that compared nonpermeable trehalose with DMSO found trehalose to be inferior, studies that devised methods to deliver nonpermeable trehalose into the cell found it comparable to DMSO. Trehalose is only comparable to DMSO when methods are devised to introduce it into the cell. There is some evidence to support using trehalose instead of using no cryopreservative agent
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An evaluation of clouds and precipitation in convection-permitting forecasts for South Africa
Since 2016, the South African Weather Service (SAWS) has been running convective-scale simulations to assist with forecast operations across southern Africa. These simulations are run with a tropical configuration of the Met Office Unified Model (UM), nested in the Met Office global model, but without data assimilation. For November 2016, convection-permitting simulations at 4.4-km and 1.5-km grid length are compared against a simulation at 10-km grid length with convection parametrization (the current UM global atmosphere configuration) to identify the benefits of increasing model resolution for forecasting convection across southern Africa. The simulations are evaluated against satellite rainfall estimates, CloudSat vertical cloud profiles, and SAWS radar data. In line with previous studies using the UM, on a monthly time scale, the diurnal cycle of convection and the distribution of rainfall rates compare better against observations when convection-permitting model configurations are used. The SAWS radar network provides a three-dimensional composite of radar reflectivity for northeast South Africa at 6-minute intervals, allowing the evaluation of the vertical development of precipitating clouds and of the timing of the onset of deep convection. Analysis of four case study days indicates that the 4.4-km simulations have a later onset of convection than the 1.5-km simulations, but there is no consistent bias of the simulations against the radar observations across the case studies
The British Society for Rheumatology Biologics Registers in Ankylosing Spondylitis (BSRBR-AS) study: Protocol for a prospective cohort study of the long-term safety and quality of life outcomes of biologic treatment
This is the final version of the article. Available from BioMed Central via the DOI in this record.BACKGROUND: Axial spondyloarthropathy typically has its onset in early adulthood and can impact significantly on quality of life. In the UK, biologic anti-tumour necrosis factor therapy is recommended for patients who are unresponsive to non-steroidal anti-inflammatory drugs. There remain several unresolved issues about the long-term safety and quality of life outcomes of biologic treatment in axial spondyloarthropathy. Long-term "real-world" surveillance data are required to complement data from randomised controlled trials. METHODS/DESIGN: We are conducting a UK-wide prospective cohort study of patients with axial spondyloarthropathy who are naïve to biologic therapy at the time of recruitment. Those about to commence anti-tumour necrosis factor biologic therapy will enter a "biologic" sub-cohort with other patients assigned to a "non-biologic" sub-cohort. The primary objective is to determine whether the use of biologic therapy is associated with an increased risk of serious infection, while secondary objectives are to assess differences in malignancy, serious comorbidity, all-cause mortality but also assess impact on specific clinical domains (physical health, mental health and quality of life) including work outcomes between biologic and non-biologic patient cohorts. Patients will be followed-up for up to 5 years. Data are obtained at baseline and at standard clinical follow-up visits - at 3, 6 and 12 months and then annually for the biologic cohort and annually for the non-biologic cohort. This study will also collect biological samples for genetic analysis. DISCUSSION: Although biologic therapy is widely used for ankylosing spondylitis patients who are unresponsive to non-steroidal anti-inflammatory drugs, the majority of the available safety information comes from rheumatoid arthritis, where increased infection risk has consistently been shown. However, given the typical demographic differences between rheumatoid arthritis and axial spondyloarthropathy patients, it is important to develop an epidemiologically rigorous cohort of patients receiving biologic therapy to effectively evaluate outcomes with regard not only to safety but also to quantify benefits across clinical, psychosocial and work outcomes. CLINICAL TRIAL REGISTRATION: This is an observational cohort study and clinical trial registration was not required or obtained.BSRBR-AS is funded by the BSR, which in turn receives funding from the manufacturers of the biologic therapies included in this study (currently AbbVie, Pfizer and UCB). Pharmaceutical companies providing funds to BSR do not have a role in the oversight of the study, but they do receive advance notice of publications on which they are able to comment. They do not have access to the data collected but can request analyses of the data, for which additional funds are provided. GJM chairs a Pfizer competitive grant committee for which he receives an honorarium. GJM and GTJ have received separate funding from AbbVie and Pfizer to study spondyloarthritis in the Scotland Registry for Ankylosing Spondylitis (SIRAS) study. LK has received an unrestricted educational grant from UCB. AK has received research funding from Abbvie and Pfizer as well as speaker/chairman fees and payments for attending advisory boards from Abbvie, Pfizer and UCB. The remaining authors have no competing interests
Alzheimer’s disease-associated complement gene variants influence plasma complement protein levels
Background: Alzheimer’s disease (AD) has been associated with immune dysregulation in biomarker and genome-wide association studies (GWAS). GWAS hits include the genes encoding complement regulators clusterin (CLU) and complement receptor 1 (CR1), recognised as key players in AD pathology, and complement proteins have been proposed as biomarkers. Main body: To address whether changes in plasma complement protein levels in AD relate to AD-associated complement gene variants we first measured relevant plasma complement proteins (clusterin, C1q, C1s, CR1, factor H) in a large cohort comprising early onset AD (EOAD; n = 912), late onset AD (LOAD; n = 492) and control (n = 504) donors. Clusterin and C1q were significantly increased (p < 0.001) and sCR1 and factor H reduced (p < 0.01) in AD plasma versus controls. ROC analyses were performed to assess utility of the measured complement biomarkers, alone or in combination with amyloid beta, in predicting AD. C1q was the most predictive single complement biomarker (AUC 0.655 LOAD, 0.601 EOAD); combining C1q with other complement or neurodegeneration makers through stepAIC-informed models improved predictive values slightly. Effects of GWS SNPs (rs6656401, rs6691117 in CR1; rs11136000, rs9331888 in CLU; rs3919533 in C1S) on protein concentrations were assessed by comparing protein levels in carriers of the minor vs major allele. To identify new associations between SNPs and changes in plasma protein levels, we performed a GWAS combining genotyping data in the cohort with complement protein levels as endophenotype. SNPs in CR1 (rs6656401), C1S (rs3919533) and CFH (rs6664877) reached significance and influenced plasma levels of the corresponding protein, whereas SNPs in CLU did not influence clusterin levels. Conclusion: Complement dysregulation is evident in AD and may contribute to pathology. AD-associated SNPs in CR1, C1S and CFH impact plasma levels of the encoded proteins, suggesting a mechanism for impact on disease risk
Addressing the human resources crisis: A case study of Cambodia's efforts to reduce maternal mortality (1980-2012)
Objective: To identify factors that have contributed to the systematic development of the Cambodian human resources for health (HRH) system with a focus on midwifery services in response to high maternal mortality in fragile resource-constrained countries. Design: Qualitative case study. Review of the published and grey literature and in-depth interviews with key informants and stakeholders using an HRH system conceptual framework developed by the authors ('House Model'; Fujita et al, 2011). Interviews focused on the perceptions of respondents regarding their contributions to strengthening midwifery services and the other external influences which may have influenced the HRH system and reduction in the maternal mortality ratio (MMR). Setting: Three rounds of interviews were conducted with senior and mid-level managers of the Ministries of Health (MoH) and Education, educational institutes and development partners. Participants: A total of 49 interviewees, who were identified through a snowball sampling technique. Main outcome measures: Scaling up the availability of 24 h maternal health services at all health centres contributing to MMR reduction. Results: The incremental development of the Cambodian HRH system since 2005 focused on the production, deployment and retention of midwives in rural areas as part of a systematic strategy to reduce maternal mortality. The improved availability and access to midwifery services contributed to significant MMR reduction. Other contributing factors included improved mechanisms for decision-making and implementation; political commitment backed up with necessary resources; leadership from the top along with a growing capacity of mid-level managers; increased MoH capacity to plan and coordinate; and supportive development partners in the context of a conducive external environment. Conclusions: Lessons from this case study point to the importance of a systemic and comprehensive approach to health and HRH system strengthening and of ongoing capacity enhancement and leadership development to ensure effective planning, implementation and monitoring of HRH policies and strategies.sch_iih3pub3197pub
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