730 research outputs found

    The influence of beam position and swimming direction on fish target strength

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    Fish orientation is consistently identified as a major influence on fish target strength (TS). Generally, orientation is defined as the tilt angle of the fish with respect to the acoustic transducer, whereas a more accurate definition includes tilt, roll, and yaw. Thus far, the influences of roll and yaw on fish TS have only been examined cursorily. We used in situ single-target data to create fish tracks, to estimate fish tilt and yaw, and correlated these estimates with TS. The results show that tilt, yaw, and beam position have a significant influence on fish TS. To investigate further how yaw and beam position affect TS, we calculated the expected backscatter from each fish within simulated fish aggregations using a backscatter model. The TS of individual fish at 38 and 120 kHz varied by as much as 11 and 19 dB with changes in yaw and beam position. Altering the fish\u27s tilt, yaw, and beam position resulted in TS differences of 14 and 26 dB at 38 and 120 kHz, respectively. Orientation had a minimal influence on an aggregation\u27s average TS if the aggregation had a variable tilt-angle distribution and was dispersed throughout the acoustic beam

    Short-term effects of deep ploughing on soil C stocks following renewal of a dairy pasture in New Zealand

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    In New Zealand’s high producing permanent pastures the topsoil constitutes a large reservoir of soil organic carbon (SOC), which shows a marked stratification with depth. As consequence, sub-surface layers can contain 10 times less carbon than the surface soil. In permanent pastures with high carbon inputs, the formation and decomposition of these surface SOC stocks are often at equilibrium and C storage shows little change over time. Pastoral based dairy systems utilising ryegrass plus clover cultivars require renewal every 7-10 years to avoid reversion to less productive grasses. This may involve spring cultivation (either no-till, shallow till or full cultivation), summer forage cropping and autumn re-grassing. It has been hypothesised that SOC stocks can be increased by inverting the soil profile at pasture renewal through infrequent (once in 25-30 years) deep mouldboard ploughing (up to 30 cm depth). Increased C sequestration occurs when the new grass quickly rebuilds SOC stocks in the new topsoil (exposed low C sub-soil) at a rate faster than the decomposition of SOC in the rich former topsoil transferred to depth (now below 15 cm). However, benefits form accelerated C storage may be offset if crop and pasture production is adversely affected by the ploughing event (e.g., as result of compaction or excessive drainage). Hence, the aim of this work was to assess the short-term effects of infrequent inversion tillage of long-term New Zealand pastoral-based dairy soils under summer crop management and autumn re-grassing. An imperfectly drained Typic Fragiaqualf under dairy grazing was deep ploughed (approx. 25 cm) and re-sown with turnip in October 2016; other treatments included were shallow (< 10 cm) cultivation and no-till. The site was core sampled (0-40 cm) before cultivation and after 5 months of turnip growth to assess changes in SOC. Plant growth, herbage quality, and nutrient leaching were monitored during the 5-month period; root growth was assessed at the end of the crop rotation. Full cultivation transferred SOC below 10 cm depth, as expected. Soil bulk density decreased whereas root mass increased (10-20 cm depth; P < 0.05) under deep cultivation only. Besides, losses of mineral N were attenuated under deep tillage, resulting in a relative increase in crop yield. The potential for infrequent inversion tillage increasing soil C sequestration as a greenhouse gas (GHG) mitigation tool is currently being tested at other sites in New Zealand

    Autophagy and mitochondrial metabolism: insights into the role and therapeutic potential in chronic myeloid leukaemia

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    Despite the development of selective BCR‐ABL‐targeting tyrosine kinase inhibitors (TKIs) transforming the management of chronic myeloid leukaemia (CML), therapy‐resistant leukaemic stem cells (LSCs) persist after TKI treatment and present an obstacle to a CML cure. Recently, we and others have made significant contributions to the field by unravelling survival dependencies in LSCs to work towards the goal of eradicating LSCs in CML patients. In this review, we describe these findings focusing on autophagy and mitochondrial metabolism, which have recently been uncovered as two essential processes for LSCs quiescence and survival, respectively. In addition, we discuss the therapeutic potential of autophagy and mitochondrial metabolism inhibition as a strategy to eliminate CML cells in patients where the resistance to TKI is driven by BCR‐ABL‐independent mechanism(s)

    The impact of a supplementary medication review and counselling service within the oncology outpatient setting

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    The impact on the care of breast cancer patients, of a pharmacy technician-led medication review and counselling clinic, provided in an outpatient setting, was investigated using a controlled randomised study. Compared to the controls, clinic patients showed a significantly improved level of understanding of their chemotherapy support medication (95% CI for difference in mean knowledge rating scores=2.165–2.826, P<0.001) and a significant reduction in the median number of support items required (two compared to five in the control, P<0.001). This resulted in a significant reduction in mean medication expenditure per patient (£26.70 vs £10.20, 95% CI for the mean difference in cost £6.72–£26.26, P<0.001). The clinic was also associated with significant reductions in chemotherapy delays (P<0.001) and dose reductions due to side effects (P=0.003). Other benefits from the clinic were a reduction in pharmacy dispensing time and a highly significant reduction in pharmacy time spent resolving post-clinic prescription queries (P<0.001). Taking into account the initial technician training cost, the scheme represented an annual saving to the Trust of over £15 000. The clinic serves as a model for those wishing to improve outpatient services to breast cancer patients

    Vulnerable Users’ Perceptions of Transport Technologies

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    As the global population continues to grow, age and urbanize, it is vital to provide accessible transport so that neither ageing nor disability constitute barriers to social inclusion. While technology can enhance urban access, there is a need to study the ways by which transport technologies - real-time information, pedestrian navigation, surveillance, and road pricing - could be more effectively adopted by users. The reason for this is that some people, and particularly vulnerable populations, are still likely to reluctantly use (or even avoid using) technologies perceived as 'unknown' and 'complicated'. Based on evidence from British and Swedish case studies on older people's perceptions of the aforementioned transport technologies, as well as on a Swedish case study of visually impaired people's perceptions, this article makes the case that technology is only one tool in a complex socio-technical system, and one which brings challenges. The authors also suggest that although vulnerable populations are not homogeneous when expressing attitudes towards transport technologies, their assessment criteria tend to be 'pro-social' as they usually consider that the societal benefits outweigh the personal benefits. Emphasising aspects linked to the technologies' pro-social potential or relevance to the individual user could increase acceptance

    A drop-in clinic for patients with poorly-controlled diabetes: a community pharmacy feasibility study

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    Background Preparatory work suggests that there may be a role for the pharmacist in managing sub-optimal medication adherence and dose titration of prescribed medicines in patients with type 2 diabetes. Patients have reported that they are receptive towards pharmacists becoming involved in their care providing that this is integrated into the care received from their medical practice. Objective To determine whether a community pharmacy diabetes drop-in clinic is feasible and acceptable to patients with poorly controlled type 2 diabetes. Setting Five community pharmacies in Norfolk, UK. Method Poorly controlled patients, as defined by a national General Practitioner incentive scheme, were invited to participate in the study by a letter posted by their medical practice. One four-hour, pharmacist clinic, where participants were able to "drop-in", was conducted in five pharmacies every week for four to six weeks. Questionnaires before and after the consultation were used to determine the clinic's effect on satisfaction with, and beliefs about, medicines and adherence along with participant satisfaction. Pharmacists had the opportunity to provide feedback via "debrief" interviews. Main outcome measure As a feasibility study, a combination of outcomes were explored including informationsatisfaction and adherence. Results Thirty-three (9.6%) of the 342 patients with type 2 diabetes posted letters were recruited from four pharmacies. Follow-up questionnaire completion rate was 88%. The clinic demonstrated little change in the parameters measured over three months. All of the participants rated their general impression of the service as good or very good and all would be happy to recommend the service to others with diabetes. Sixteen participants (59%) stated that it would make them more likely to consult their pharmacist in the future. Pharmacists enjoyed providing the service as it allowed them to interact more formally, and for longer, with patients. Conclusion This research has demonstrated that a community pharmacy drop-in clinic is feasible and likely to be acceptable to both patients and pharmacists; however, cost effectiveness of such a service should be explored in future studies. Further thought should also be given to how this service can complement that provided by a nurse in the medical practice and how the pharmacist can provide additional benefit to the NHS

    Laparoscopic treatment of isolated superficial peritoneal endometriosis for managing chronic pelvic pain in women:study protocol for a randomised controlled feasibility trial (ESPriT1)

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    Background: Endometriosis (where endometrial-like tissue is found outside the uterus) affects ~ 176 million women worldwide and can lead to debilitating pelvic pain. Three subtypes of endometriosis exist, with ~ 80% of women having superficial peritoneal endometriosis (SPE). Endometriosis is diagnosed by laparoscopy and, if SPE is found, gynaecologists usually remove it surgically. However, many women get limited pain relief from surgical removal of SPE. We plan to undertake a future large trial where women who have only SPE found at initial laparoscopy are randomly allocated to have surgical removal (excision or ablation) of SPE, or not. Ultimately, we want to determine whether surgical removal improves overall symptoms and quality of life, or whether surgery is of no benefit, exacerbates symptoms, or even causes harm. The primary objective of this feasibility study is to determine what proportion of women with suspected SPE undergoing diagnostic laparoscopy will agree to randomisation. The secondary objectives are to determine if there are differences in key prognostic parameters between eligible women that agree to be randomised and those that decline; how many women having laparoscopy for investigation of chronic pelvic pain are eligible for the trial; the range of treatment effects and variability in outcomes and the most acceptable methods of recruitment, randomisation and assessment tools. Methods: We will recruit up to 90 women with suspected SPE undergoing diagnostic laparoscopy over a 9-month recruitment period in four Scottish hospitals and randomise them 1:1 to either diagnostic laparoscopy alone (with a sham port to achieve blinding of the allocation) or surgical removal of endometriosis. Baseline characteristics, e.g. age, index of social deprivation, ethnicity, and intensity/duration of pain will be collected. Participants will be followed up by online questionnaires assessing pain, physical and emotional function at baseline, 3 months, 6 months and 12 months. Discussion: Recruitment to a randomised controlled trial to assess the effectiveness of surgery for endometriosis may be challenging because of preconceived ideas about treatment success amongst patients and clinicians. We have designed this study to assess feasibility of recruitment and to inform the design of our future definitive trial. Trial registration: ClincicalTrials.gov, NCT04081532 Status: Recruiting

    De Broglie Wavelength of a Nonlocal Four-Photon

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    Superposition is one of the most distinct features of quantum theory and has been demonstrated in numerous realizations of Young's classical double-slit interference experiment and its analogues. However, quantum entanglement - a significant coherent superposition in multiparticle systems - yields phenomena that are much richer and more interesting than anything that can be seen in a one-particle system. Among them, one important type of multi-particle experiments uses path-entangled number-states, which exhibit pure higher-order interference and allow novel applications in metrology and imaging such as quantum interferometry and spectroscopy with phase sensitivity at the Heisenberg limit or quantum lithography beyond the classical diffraction limit. Up to now, in optical implementations of such schemes lower-order interference effects would always decrease the overall performance at higher particle numbers. They have thus been limited to two photons. We overcome this limitation and demonstrate a linear-optics-based four-photon interferometer. Observation of a four-particle mode-entangled state is confirmed by interference fringes with a periodicity of one quarter of the single-photon wavelength. This scheme can readily be extended to arbitrary photon numbers and thus represents an important step towards realizable applications with entanglement-enhanced performance.Comment: 19 pages, 4 figures, submitted on November 18, 200

    Issues potentially affecting quality of life arising from long-term medicines use: a qualitative study

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    Background Polypharmacy is increasing and managing large number of medicines may create a burden for patients. Many patients have negative views of medicines and their use can adversely affect quality of life. No studies have specifically explored the impact of general long-term medicines use on quality of life. Objective To determine the issues which patients taking long-term medicines consider affect their day-to-day lives, including quality of life. Setting Four primary care general practices in North West England Methods Face-to-face interviews with adults living at home, prescribed four or more regular medicines for at least 1 year. Interviewees were identified from primary care medical records and purposively selected to ensure different types of medicines use. Interviews were recorded, transcribed and analysed thematically. Results Twenty-one interviews were conducted and analysed. Patients used an average of 7.8 medicines, 51 % were preventive, 40 % for symptom relief and 9 % treatment. Eight themes emerged: relationships with health professionals, practicalities, information, efficacy, side effects, attitudes, impact and control. Ability to discuss medicines with health professionals varied and many views were coloured by negative experiences, mainly with doctors. All interviewees had developed routines for using multiple medicines, some requiring considerable effort. Few felt able to exert control over medicines routines specified by health professionals. Over half sought additional information about medicines whereas others avoided this, trusting in doctors to guide their medicines use. Patients recognised their inability to assess efficacy for many medicines, notably those used for prophylaxis. All were concerned about possible side effects and some had poor experiences of discussing concerns with doctors. Medicines led to restrictions on social activities and personal life to the extent that, for some, life can revolve around medicines. Conclusion There is a multiplicity and complexity of issues surrounding medicines use, which impact on day-to-day lives for patients with long-term conditions. While most patients adapt to long-term medicines use, others did so at some cost to their quality of life
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