2,955 research outputs found
Quantum Hall induced currents and the magnetoresistance of a quantum point contact
We report an investigation of quantum Hall induced currents by simultaneous
measurements of their magnetic moment and their effect on the conductance of a
quantum point contact (QPC). Features in the magnetic moment and QPC resistance
are correlated at Landau-level filling factors nu=1, 2 and 4, which
demonstrates the common origin of the effects. Temperature and non-linear sweep
rate dependences are observed to be similar for the two effects. Furthermore,
features in the noise of the induced currents, caused by breakdown of the
quantum Hall effect, are observed to have clear correlations between the two
measurements. In contrast, there is a distinct difference in the way that the
induced currents decay with time when the sweeping field halts at integer
filling factor. We attribute this difference to the fact that, while both
effects are sensitive to the magnitude of the induced current, the QPC
resistance is also sensitive to the proximity of the current to the QPC
split-gate. Although it is clearly demonstrated that induced currents affect
the electrostatics of a QPC, the reverse effect, the QPC influencing the
induced current, was not observed
Public Sentiment and Discourse on Domestic Violence During the COVID-19 Pandemic in Australia: Analysis of Social Media Posts.
Background: Measuring public response during COVID-19 is an important way of ensuring the suitability and effectiveness of epidemic response efforts. An analysis of social media provides an approximation of public sentiment during an emergency like the current pandemic. The measures introduced across the globe to help curtail the spread of the coronavirus have led to the development of a situation labeled as a âperfect storm,â triggering a wave of domestic violence. As people use social media to communicate their experiences, analyzing public discourse and sentiment on social platforms offers a way to understand concerns and issues related to domestic violence during the COVID-19 pandemic.
Objective: This study was based on an analysis of public discourse and sentiment related to domestic violence during the stay-at-home periods of the COVID-19 pandemic in Australia in 2020. It aimed to understand the more personal self-reported experiences, emotions, and reactions toward domestic violence that were not always classified or collected by official public bodies during the pandemic.
Methods: We searched social media and news posts in Australia using key terms related to domestic violence and COVID-19 during 2020 via digital analytics tools to determine sentiments related to domestic violence during this period.
Results: The study showed that the use of sentiment and discourse analysis to assess social media data is useful in measuring the public expression of feelings and sharing of resources in relation to the otherwise personal experience of domestic violence. There were a total of 63,800 posts across social media and news media. Within these posts, our analysis found that domestic violence was mentioned an average of 179 times a day. There were 30,100 tweets, 31,700 news reports, 1500 blog posts, 548 forum posts, and 7 comments (posted on news and blog websites). Negative or neutral sentiment centered on the sharp rise in domestic violence during different lockdown periods of the 2020 pandemic, and neutral and positive sentiments centered on praise for efforts that raised awareness of domestic violence as well as the positive actions of domestic violence charities and support groups in their campaigns. There were calls for a positive and proactive handling (rather than a mishandling) of the pandemic, and results indicated a high level of public discontent related to the rising rates of domestic violence and the lack of services during the pandemic.
Conclusions: This study provided a timely understanding of public sentiment related to domestic violence during the COVID-19 lockdown periods in Australia using social media analysis. Social media represents an important avenue for the dissemination of information; posts can be widely dispersed and easily accessed by a range of different communities who are often difficult to reach. An improved understanding of these issues is important for future policy direction. Heightened awareness of this could help agencies tailor and target messaging to maximize impact
The influence of the long-lived quantum Hall potential on the characteristics of quantum devices
Novel hysteretic effects are reported in magneto-transport experiments on
lateral quantum devices. The effects are characterized by two vastly different
relaxation times (minutes and days). It is shown that the observed phenomena
are related to long-lived eddy currents. This is confirmed by torsion-balance
magnetometry measurements of the same 2-dimensional electron gas (2DEG)
material. These observations show that the induced quantum Hall potential at
the edges of the 2DEG reservoirs influences transport through the devices, and
have important consequences for the magneto-transport of all lateral quantum
devices.Comment: 5 pages, 4 figure
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Offering statins to a population attending health checks with a 10-year cardiovascular disease risk between 10% and 20.
BACKGROUND: In 2014 the UK National Institute for Health and Care Excellence recommended reducing the threshold for offering statin therapy to patients from a 10-year modelled risk of cardiovascular disease (CVD) of 20% to 10%. AIM: To describe the response of patients in UK primary care with a CVD risk between 10% and 20% to an invitation to attend a consultation to discuss statins. DESIGN AND SETTING: Review of electronic medical records at one GP practice in the East of England. METHOD: We invited all patients who had attended an NHS Health Check at the practice, had a QRisk(ÂŽ) score between 10% and 20%, and were not prescribed statins to attend designated clinics in the practice to discuss starting statins. We reviewed the medical records to identify those who had attended the clinics and those who had chosen to start a statin. RESULTS: Of 410 patients invited, 100 (24.4%) patients attended the designated clinics and 45 (11%) chose to start a statin. Those who chose to start a statin were older and with a higher QRisk(ÂŽ) than those who did not. Among those who attended, individuals who started a statin had a higher QRisk(ÂŽ) than those who did not and were more likely to be current or ex-smokers. CONCLUSIONS: The proportion choosing to start a statin was substantially lower than previously estimated. Large population-based studies with long-term follow-up are needed to assess the impact on health and workload of this change in guidance.JU-S is funded by a National Institute of Health Research Clinical Lectureship. The views expressed in this publication are those of the authors and not necessarily those of the NHS, the National Institute for Health Research, or the Department of Health.This is the author accepted manuscript. The final version is available from Wiley via http://dx.doi.org/10.1111/ijcp.1274
Pathological mechanisms and therapeutic outlooks for arthrofibrosis
Arthrofibrosis is a fibrotic joint disorder that begins with an inflammatory reaction to insults such as injury, surgery and infection. Excessive extracellular matrix and adhesions contract pouches, bursae and tendons, cause pain and prevent a normal range of joint motion, with devastating consequences for patient quality of life. Arthrofibrosis affects people of all ages, with published rates varying. The risk factors and best management strategies are largely unknown due to a poor understanding of the pathology and lack of diagnostic biomarkers. However, current research into the pathogenesis of fibrosis in organs now informs the understanding of arthrofibrosis. The process begins when stress signals stimulate immune cells. The resulting cascade of cytokines and mediators drives fibroblasts to differentiate into myofibroblasts, which secrete fibrillar collagens and transforming growth factor-β (TGF-β). Positive feedback networks then dysregulate processes that normally terminate healing processes. We propose two subtypes of arthrofibrosis occur: active arthrofibrosis and residual arthrofibrosis. In the latter the fibrogenic processes have resolved but the joint remains stiff. The best therapeutic approach for each subtype may differ significantly. Treatment typically involves surgery, however, a pharmacological approach to correct dysregulated cell signalling could be more effective. Recent research shows that myofibroblasts are capable of reversing differentiation, and understanding the mechanisms of pathogenesis and resolution will be essential for the development of cell-based treatments. Therapies with significant promise are currently available, with more in development, including those that inhibit TGF-β signalling and epigenetic modifications. This review focuses on pathogenesis of sterile arthrofibrosis and therapeutic treatments
Structure and play: rethinking regulation in the higher education sector
This paper explores possible tactics for academics working within a context of increasing regulation and constraint. One suggested tactic is to move outside of a creativity-conformity binary. Rather than understanding creativity and conformity as separable, where one is seen as excluding the other, the authors consider the potential of examining the relationships between them. The theme of 'structure and play' illustrates the argument. In the first part of the paper, using various examples from art and design - fields generally associated with creativity - the authors explore the interrelatedness of creativity and conformity. For example, how might design styles, which are generally understood as creative outcomes, constrain creativity and lead to conformity within the design field? Is fashion producing creativity or conformity? Conversely, the ways in which conformity provides the conditions for creativity are also examined. For example, the conformity imposed by the state on artists in the former communist bloc contributed to a thriving underground arts movement which challenged conformity and state regulation. Continuing the theme of 'structure and play', the authors recount a story from an Australian university which foregrounds the ongoing renegotiation of power relations in the academy. This account illustrates how programmatic government in a university, with its aim of regulating conduct, can contribute to unanticipated outcomes. The authors propose that a Foucauldian view of distributed power is useful for academics operating in a context of increasing regulation, as it brings into view sites where power might begin to be renegotiated
Field trial evaluation of the accumulation of omega-3 long chain polyunsaturated fatty acids in transgenic Camelina sativa: making fish oil substitutes in plants
6 pĂĄginas, 2 figurasThe global consumption of fish oils currently exceeds one million tonnes, with the natural de novo source of these important fatty acids forming the base of marine foodwebs. Here we describe the first field-based evaluation of a terrestrial source of these essential nutrients, synthesised in the seeds of transgenic Camelina sativa plants via the heterologous reconstitution of the omega-3 long chain polyunsaturated fatty acid biosynthetic pathway. Our data demonstrate the robust nature of this novel trait, and the feasibility of making fish oils in genetically modified crops. Moreover, to our knowledge, this is the most complex example of plant genetic engineering to undergo environmental release and field evaluation.Rothamsted Research receives grand-aided support from the Biotechnology and Biological Sciences Research Council (BBSRC), UK. This study was supported via the Strategic Programme Grant BBS/E/C/00005207. We thank the staff of the Rothamsted Experimental Farm for their help in the management of this experimental trial. We acknowledge BASF Plant Sciences for generous provision of the vector system used in this study.Peer reviewe
Risk prediction models for colorectal cancer in people with symptoms: a systematic review
Abstract
Background
Colorectal cancer (CRC) is the fourth leading cause of cancer-related death in Europe and the United States. Detecting the disease at an early stage improves outcomes. Risk prediction models which combine multiple risk factors and symptoms have the potential to improve timely diagnosis. The aim of this review is to systematically identify and compare the performance of models that predict the risk of primary CRC among symptomatic individuals.
Methods
We searched Medline and EMBASE to identify primary research studies reporting, validating or assessing the impact of models. For inclusion, models needed to assess a combination of risk factors that included symptoms, present data on model performance, and be applicable to the general population. Screening of studies for inclusion and data extraction were completed independently by at least two researchers.
Results
Twelve thousand eight hundred eight papers were identified from the literature search and three through citation searching. 18 papers describing 15 risk models were included. Nine were developed in primary care populations and six in secondary care. Four had good discrimination (AUROCâ>â0.8) in external validation studies, and sensitivity and specificity ranged from 0.25 and 0.99 to 0.99 and 0.46 depending on the cut-off chosen.
Conclusions
Models with good discrimination have been developed in both primary and secondary care populations. Most contain variables that are easily obtainable in a single consultation, but further research is needed to assess clinical utility before they are incorporated into practice
Transgenic plants as a sustainable, terrestrial source of fish oils
An alternative, sustainable source of omega-3 long chain polyunsaturated fatty acids is widely recognized as desirable, helping to reduce pressure on current sources (wild capture fisheries) and providing a de novo source of these health beneficial fatty acids. This review will consider the efforts and progress to develop transgenic plants as terrestrial sources of omega-3 fish oils, focusing on recent developments and the possible explanations for advances in the field. We also consider the utility of such a source for use in aquaculture, since this industry is the major consumer of oceanic supplies of omega-3 fish oils. Given the importance of the aquaculture industry in meeting global requirements for healthy foodstuffs, an alternative source of omega-3 fish oils represents a potentially significant breakthrough for this production system. Transgenic Camelina seeds engineered to accumulate the omega-3 fatty acids EPA and DHA, represent a sustainable alternative to fish oils
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