Time-Delay Interferometry

Equal-arm interferometric detectors of gravitational radiation allow phase measurements many orders of magnitude below the intrinsic phase stability of the laser injecting light into their arms. This is because the noise in the laser light is common to both arms, experiencing exactly the same delay, and thus cancels when it is differenced at the photo detector. In this situation, much lower level secondary noises then set overall performance. If, however, the two arms have different lengths (as will necessarily be the case with space-borne interferometers), the laser noise experiences different delays in the two arms and will hence not directly cancel at the detector. In order to solve this problem, a technique involving heterodyne interferometry with unequal arm lengths and independent phase-difference readouts has been proposed. It relies on properly time-shifting and linearly combining independent Doppler measurements, and for this reason it has been called Time-Delay Interferometry (or TDI). This article provides an overview of the theory and mathematical foundations of TDI as it will be implemented by the forthcoming space-based interferometers such as the Laser Interferometer Space Antenna (LISA) mission. We have purposely left out from this first version of our ``Living Review'' article on TDI all the results of more practical and experimental nature, as well as all the aspects of TDI that the data analysts will need to account for when analyzing the LISA TDI data combinations. Our forthcoming ``second edition'' of this review paper will include these topics.Comment: 51 pages, 11 figures. To appear in: Living Reviews. Added conten

Wide variation in susceptibility of transmitted/founder HIV-1 subtype C Isolates to protease inhibitors and association with in vitro replication efficiency

© 2016 The Author(s).The gag gene is highly polymorphic across HIV-1 subtypes and contributes to susceptibility to protease inhibitors (PI), a critical class of antiretrovirals that will be used in up to 2 million individuals as second-line therapy in sub Saharan Africa by 2020. Given subtype C represents around half of all HIV-1 infections globally, we examined PI susceptibility in subtype C viruses from treatment-naïve individuals. PI susceptibility was measured in a single round infection assay of full-length, replication competent MJ4/gag chimeric viruses, encoding the gag gene and 142 nucleotides of pro derived from viruses in 20 patients in the Zambia-Emory HIV Research Project acute infection cohort. Ten-fold variation in susceptibility to PIs atazanavir and lopinavir was observed across 20 viruses, with EC50 s ranging 0.71-6.95 nM for atazanvir and 0.64-8.54 nM for lopinavir. Ten amino acid residues in Gag correlated with lopinavir EC50 (p < 0.01), of which 380 K and 389I showed modest impacts on in vitro drug susceptibility. Finally a significant relationship between drug susceptibility and replication capacity was observed for atazanavir and lopinavir but not darunavir. Our findings demonstrate large variation in susceptibility of PI-naïve subtype C viruses that appears to correlate with replication efficiency and could impact clinical outcomes

Depression, Emotional Eating and Food Choice

The prevalence of depression has been steadily growing throughout the years, especially among college students. Depression has been rated third amongst the presenting problems in college counseling centers (Drum & Baron, 1998) and studies have indicated that as much as 80% of college students say they have experienced some form of depression throughout college (Westefeld & Furr, 1987). Not only does depression affect college students, but positive affect does as well. Evidence that suggests that those with a history of depression may get the most benefit from having positive affect, given a negative relationship between positive affect and depressive symptoms has been found to be stronger when people are under stress, which may be common in college students (Pruchno & Meeks, 2004). Levels of negative or positive moods, which may lead to higher or levels of emotional eating, may also affect food choice. Language use also affects health, where positive emotion words are linearly related to improved health, and negative emotion words are curvilinearly related and have an inverse-U function (Pennebaker, Mayne & Francis, 1997). In this current research, I examined the relationship between negative/positive affect and their relationship to emotional eating and food choice. Hypotheses include that higher levels of depressed affect will result in higher levels of emotional eating, which in turn will increase sweet food eating, especially in women. Higher levels of positive affect are hypothesized to decrease levels of emotional eating, which in turn will decrease sweet food eating. Results indicated that emotional eating played a role in depressed/positive affect and sweet food eating. The findings of the study supported the hypotheses, suggesting that mood plays a role in food choice

Positive and negative well-being and objectively measured sedentary behaviour in older adults: evidence from three cohorts

Background: Sedentary behaviour is related to poorer health independently of time spent in moderate to vigorous physical activity. The aim of this study was to investigate whether wellbeing or symptoms of anxiety or depression predict sedentary behaviour in older adults. Method: Participants were drawn from the Lothian Birth Cohort 1936 (LBC1936) (n = 271), and the West of Scotland Twenty-07 1950s (n = 309) and 1930s (n = 118) cohorts. Sedentary outcomes, sedentary time, and number of sit-to-stand transitions, were measured with a three-dimensional accelerometer (activPAL activity monitor) worn for 7 days. In the Twenty-07 cohorts, symptoms of anxiety and depression were assessed in 2008 and sedentary outcomes were assessed ~ 8 years later in 2015 and 2016. In the LBC1936 cohort, wellbeing and symptoms of anxiety and depression were assessed concurrently with sedentary behaviour in 2015 and 2016. We tested for an association between wellbeing, anxiety or depression and the sedentary outcomes using multivariate regression analysis. Results: We observed no association between wellbeing or symptoms of anxiety and the sedentary outcomes. Symptoms of depression were positively associated with sedentary time in the LBC1936 and Twenty-07 1950s cohort, and negatively associated with number of sit-to-stand transitions in the LBC1936. Meta-analytic estimates of the association between depressive symptoms and sedentary time or number of sit-to-stand transitions, adjusted for age, sex, BMI, long-standing illness, and education, were β = 0.11 (95% CI = 0.03, 0.18) and β = − 0.11 (95% CI = − 0.19, −0.03) respectively. Conclusion: Our findings indicate that depressive symptoms are positively associated with sedentary behavior. Future studies should investigate the causal direction of this association

Regulation of neutrophil senescence by microRNAs

Neutrophils are rapidly recruited to sites of tissue injury or infection, where they protect against invading pathogens. Neutrophil functions are limited by a process of neutrophil senescence, which renders the cells unable to respond to chemoattractants, carry out respiratory burst, or degranulate. In parallel, aged neutrophils also undergo spontaneous apoptosis, which can be delayed by factors such as GMCSF. This is then followed by their subsequent removal by phagocytic cells such as macrophages, thereby preventing unwanted inflammation and tissue damage. Neutrophils translate mRNA to make new proteins that are important in maintaining functional longevity. We therefore hypothesised that neutrophil functions and lifespan might be regulated by microRNAs expressed within human neutrophils. Total RNA from highly purified neutrophils was prepared and subjected to microarray analysis using the Agilent human miRNA microarray V3. We found human neutrophils expressed a selected repertoire of 148 microRNAs and that 6 of these were significantly upregulated after a period of 4 hours in culture, at a time when the contribution of apoptosis is negligible. A list of predicted targets for these 6 microRNAs was generated from http://mirecords.biolead.org and compared to mRNA species downregulated over time, revealing 83 genes targeted by at least 2 out of the 6 regulated microRNAs. Pathway analysis of genes containing binding sites for these microRNAs identified the following pathways: chemokine and cytokine signalling, Ras pathway, and regulation of the actin cytoskeleton. Our data suggest that microRNAs may play a role in the regulation of neutrophil senescence and further suggest that manipulation of microRNAs might represent an area of future therapeutic interest for the treatment of inflammatory disease

IPTF Search for An Optical Counterpart to Gravitational-Wave TransientT GW150914

The American Astronomical Society. All rights reserved..The intermediate Palomar Transient Factory (iPTF) autonomously responded to and promptly tiled the error region of the first gravitational-wave event GW150914 to search for an optical counterpart. Only a small fraction of the total localized region was immediately visible in the northern night sky, due both to Sun-angle and elevation constraints. Here, we report on the transient candidates identified and rapid follow-up undertaken to determine the nature of each candidate. Even in the small area imaged of 126 deg2, after extensive filtering, eight candidates were deemed worthy of additional follow-up. Within two hours, all eight were spectroscopically classified by the Keck II telescope. Curiously, even though such events are rare, one of our candidates was a superluminous supernova. We obtained radio data with the Jansky Very Large Array and X-ray follow-up with the Swift satellite for this transient. None of our candidates appear to be associated with the gravitational-wave trigger, which is unsurprising given that GW150914 came from the merger of two stellar-mass black holes. This end-to-end discovery and follow-up campaign bodes well for future searches in this post-detection era of gravitational waves

Barriers and facilitators to adherence to group exercise in institutionalized older people living with dementia: a systematic review

Objectives Research suggests targeted exercise is important for people living with dementia, especially those living in residential care. The aim of this review was to collect and synthesize evidence on the known barriers and facilitators to adherence to group exercise of institutionalized older people living with dementia. Methods We searched all available electronic databases. Additionally, we searched trial registries (clinicaltrial.gov, and WHO ICTRP) for ongoing studies. We searched for and included papers from January 1990 until September 2017 in any language. We included randomized, non-randomized trials. Studies were not eligible if participants were either healthy older people or people suffering from dementia but not living in an institution. Studies were also excluded if they were not focused on barriers and facilitators to adherence to group exercise. Results Using narrative analysis, we identified the following themes for barriers: bio-medical reasons and mental wellbeing and physical ability, relationships dynamics, and socioeconomic reasons. The facilitators were grouped under the following thematic frames: bio-medical benefits and benefits related to physical ability, feelings and emotions and confidence improvements, therapist and group relationships dynamics and activity related reasons. Conclusions We conclude that institutionalized older people living with dementia, even those who are physically frail, incontinent and/or have mild dementia can demonstrate certain level of exercise adherence, and therefore can respond positively to exercise programs. Tailored, individually-adjusted and supported physical activity, led by a knowledgeable, engaging and well communicating therapist/facilitator improves the adherence to group exercise interventions of institutionalized older people living with dementia

How students perceive medical competences: a cross-cultural study between the Medical Course in Portugal and African Portuguese Speaking Countries

<p>Abstract</p> <p>Background</p> <p>A global effort has been made in the last years to establish a set of core competences that define the essential professional competence of a physician. Regardless of the environment, culture or medical education conditions, a set of core competences is required for medical practice worldwide. Evaluation of educational program is always needed to assure the best training for medical students and ultimately best care for patients. The aim of this study was to determine in what extent medical students in Portugal and Portuguese speaking African countries, felt they have acquired the core competences to start their clinical practice. For this reason, it was created a measurement tool to evaluate self-perceived competences, in different domains, across Portuguese and Portuguese-speaking African medical schools.</p> <p>Methods</p> <p>The information was collected through a questionnaire that defines the knowledge, attitudes and skills that future doctors should acquire. The Cronbach's Alpha and Principal Components Analysis (PCA) were used to evaluate the reliability of the questionnaire. In order to remove possible confounding effect, individual scores were standardized by country.</p> <p>Results</p> <p>The order of the domain's scores was similar between countries. After standardization, Personal Attitudes and Professional Behavior showed median scores above the country global median and Knowledge alone showed median score below the country global median. In Portugal, Clinical Skills showed score below the global median. In Angola, Clinical Skills and General Skills showed a similar result. There were only significant differences between countries in Personal Attitudes (p < 0.001) and Professional Behavior (p = 0.043).</p> <p>Conclusions</p> <p>The reliability of the instrument in Portuguese and Portuguese-speaking African medical schools was confirmed. Students have perceived their level of competence in personal attitudes in a high level and in opposite, knowledge and clinical skills with some weaknesses.</p

Parenting a child with phenylketonuria or galactosemia: implications for health-related quality of life

Parents of children with chronic disorders have an impaired health-related quality of life (HRQoL) compared to parents of healthy children. Remarkably, parents of children with a metabolic disorder reported an even lower HRQoL than parents of children with other chronic disorders. Possibly, the uncertainty about the course of the disease and the limited life expectancy in many metabolic disorders are important factors in the low parental HRQoL. Therefore, we performed a cross-sectional study in parents of children with phenylketonuria (PKU, OMIM #261600) and galactosemia (OMIM #230400), metabolic disorders not affecting life expectancy, in order to investigate their HRQoL compared to parents of healthy children and to parents of children with other metabolic disorders. A total of 185 parents of children with PKU and galactosemia aged 1-19 years completed two questionnaires. Parents of children with PKU or galactosemia reported a HRQoL comparable to parents of healthy children and a significantly better HRQoL than parents of children with other metabolic disorders. Important predictors for parental mental HRQoL were the psychosocial factors emotional support and loss of friendship. As parental mental functioning influences the health, development and adjustment of their children, it is important that treating physicians also pay attention to the wellbeing of the parents. The insight that emotional support and loss of friendship influence the HRQoL of the parents enables treating physicians to provide better support for these parents

Measurement of the cross-section and charge asymmetry of WW bosons produced in proton-proton collisions at s=8\sqrt{s}=8 TeV with the ATLAS detector

This paper presents measurements of the $W^+ \rightarrow \mu^+\nu$ and $W^- \rightarrow \mu^-\nu$ cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13