244 research outputs found
Afshar's Experiment does not show a Violation of Complementarity
A recent experiment performed by S. Afshar [first reported by M. Chown, New
Scientist {\bf 183}, 30 (2004)] is analyzed. It was claimed that this
experiment could be interpreted as a demonstration of a violation of the
principle of complementarity in quantum mechanics. Instead, it is shown here
that it can be understood in terms of classical wave optics and the standard
interpretation of quantum mechanics. Its performance is quantified and it is
concluded that the experiment is suboptimal in the sense that it does not fully
exhaust the limits imposed by quantum mechanics.Comment: 6 pages, 6 figure
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A feasibility randomised controlled trial of a motivational interviewing-based intervention for weight loss maintenance in adults
Background
Obesity has significant health and NHS cost implications. Relatively small reductions in weight have clinically important benefits, but long-term weight loss maintenance (WLM) is challenging. Behaviour change interventions have been identified as key for WLM. Motivation is crucial to supporting behaviour change, and motivational interviewing (MI) has been identified as a successful approach to changing health behaviours. The study was designed as an adequately powered, pragmatic randomised controlled trial (RCT); however, owing to recruitment issues, the study became a feasibility trial.
Objectives
To assess recruitment, retention, feasibility, acceptability, compliance and delivery of a 12-month intervention to support WLM. Secondary objectives were to assess the impact of the intervention on body mass index (BMI) and other secondary outcomes.
Design
Three-arm individually randomised controlled trial comprising an intensive arm, a less intensive arm and a control arm.
Setting
Community setting in South Wales and the East Midlands.
Participants
Individuals aged 18�70 years with a current or previous BMI of ??30 kg/m2 who could provide evidence of at least 5% weight loss during the previous 12 months.
Intervention
Participants received individually tailored MI, which included planning and self-monitoring. The intensive arm received six face-to-face sessions followed by nine telephone sessions. The less intensive arm received two face-to-face sessions followed by two telephone sessions. The control arm received a leaflet advising them on healthy lifestyle.
Main outcome measures
Feasibility outcomes included numbers recruited, retention and adherence. The primary effectiveness outcome was BMI at 12 months post randomisation. Secondary outcomes included waist circumference, waist-to-hip ratio, physical activity, proportion maintaining weight loss, diet, quality of life, health service resource usage, binge eating and well-being. A process evaluation assessed intervention delivery, adherence, and participants� and practitioners� views. Economic analysis aimed to assess cost-effectiveness in terms of quality-adjusted life-years (QALYs).
Results
A total of 170 participants were randomised. Retention was good (84%) and adherence was excellent (intensive, 83%; less intensive, 91%). The between-group difference in mean BMI indicated the intensive arm had BMIs 1.0?kg/m2 lower than the controls [95% confidence interval (CI) �2.2 kg/m2 to 0.2?kg/m2]. Similarly, a potential difference was found in weight (average difference of 2.8?kg, 95% CI �6.1 kg to 0.5?kg). The intensive arm had odds of maintaining on average 43% [odds ratio(OR) 1.4, 95% CI 0.6 to 3.5] higher than controls. None of these findings were statistically significant. Further analyses controlling for level of adherence indicated that average BMI was 1.2?kg/m2 lower in the intensive arm than the control arm (95% CI �2.5?kg/m2 to 0.0?kg/m2). The intensive intervention led to a statistically significant difference in weight (mean �3.7?kg, 95% CI �7.1?kg to �0.3?kg). The other secondary outcomes showed limited evidence of differences between groups. The intervention was delivered as planned, and both practitioners and participants were positive about the intervention and its impact. Although not powered to assess cost-effectiveness, results of this feasibility study suggest that neither intervention as currently delivered is likely to be cost-effective in routine practice.
Conclusion
This is the first trial of an intervention for WLM in the UK, the intervention is feasible and acceptable, and retention and adherence were high. The main effectiveness outcome showed a promising mean difference in the intensive arm. Owing to the small sample size, we are limited in the conclusions we can draw. However, findings suggest that the intensive intervention may facilitate long-term weight maintenance and, therefore, further testing in an effectiveness trial may be indicated. Research examining WLM is in its infancy, further research is needed to develop our understanding of WLM and to expand theory to inform the development of interventions to be tested in rigorously designed RCTs with cost-effectiveness assessed
Time-dependent visibility modelling of a relativistic jet in the X-ray binary MAXI J1803-298
Tracking the motions of transient jets launched by low-mass X-ray binaries
(LMXBs) is critical for determining the moment of jet ejection, and identifying
any corresponding signatures in the accretion flow. However, these jets are
often highly variable and can travel across the resolution element of an image
within a single observation, violating a fundamental assumption of aperture
synthesis. We present a novel approach in which we directly fit a single
time-dependent model to the full set of interferometer visibilities, where we
explicitly parameterise the motion and flux density variability of the emission
components, to minimise the number of free parameters in the fit, while
leveraging information from the full observation. This technique allows us to
detect and characterize faint, fast-moving sources, for which the standard time
binning technique is inadequate. We validate our technique with synthetic
observations, before applying it to three Very Long Baseline Array (VLBA)
observations of the black hole candidate LMXB MAXI J1803-298 during its 2021
outburst. We measured the proper motion of a discrete jet component to be
mas/hr, and thus we infer an ejection date of MJD
, which occurs just after the peak of a radio flare
observed by the Australia Telescope Compact Array (ATCA) and the Atacama Large
Millimeter/Sub-Millimeter Array (ALMA), while MAXI J1803-298 was in the
intermediate state. Further development of these new VLBI analysis techniques
will lead to more precise measurements of jet ejection dates, which, combined
with dense, simultaneous multi-wavelength monitoring, will allow for clearer
identification of jet ejection signatures in the accretion flow.Comment: 15 pages, 9 figures, 4 tables; Accepted for publication in MNRA
Significant ophthalmoarthropathy associated with ectodermal dysplasia in a child with Marshall-Stickler overlap: a case report
© 2008 Al Kaissi et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens
‘Something that helped the whole picture’: Experiences of parents offered rapid prenatal exome sequencing in routine clinical care in the English National Health Service
Objectives: In October 2020, rapid prenatal exome sequencing (pES) was introduced into routine National Health Service (NHS) care in England. This study aimed to explore parent experiences and their information and support needs from the perspective of parents offered pES and of health professionals involved in its delivery. Methods: In this qualitative study, semi-structured interviews were conducted with 42 women and 6 male partners and 63 fetal medicine and genetic health professionals. Interviews were transcribed verbatim and analysed using thematic analysis. Results: Overall views about pES were positive and parents were grateful to be offered the test. Highlighted benefits of pES included the value of the additional information for pregnancy management and planning for future pregnancies. An anxious wait for results was common, often associated with the need to make decisions near to 24Â weeks in pregnancy when there are legal restrictions for late termination. Descriptions of dealing with uncertainty were also common, even when results had been returned. Many parents described pES results as informing decision-making around whether or not to terminate pregnancy. Some professionals were concerned that a non-informative result could be overly reassuring and highlighted that careful counselling was needed to ensure parents have a good understanding of what the result means for their pregnancy. Emotional support from professionals was valued; however, some parents felt that post-test support was lacking. Conclusion: Parents and professionals welcomed the introduction of pES. Results inform parents' decision-making around the termination of pregnancy. When there are no diagnostic findings or uncertain findings from pES, personalised counselling that considers scans and other tests are crucial. Directing parents to reliable online sources of information and providing emotional support throughout could improve their experiences of care
Delivery of a national prenatal exome sequencing service in England: a mixed methods study exploring healthcare professionals’ views and experiences
Copyright \ua9 2024 Peter, Mellis, McInnes-Dean, Daniel, Walton, Fisher, Leeson-Beevers, Allen, Baple, Beleza-Meireles, Bertoli, Campbell, Canham, Cilliers, Cobben, Eason, Harrison, Holder-Espinasse, Male, Mansour, McEwan, Park, Smith, Stewart, Tapon, Vasudevan, Williams, Wu, Chitty and Hill.Introduction: In October 2020, rapid prenatal exome sequencing (pES) was introduced into routine National Health Service (NHS) care in England, requiring the coordination of care from specialist genetics, fetal medicine (FM) and laboratory services. This mixed methods study explored the experiences of professionals involved in delivering the pES service during the first 2 years of its delivery in the NHS. Methods: A survey (n = 159) and semi-structured interviews (n = 63) with healthcare professionals, including clinical geneticists, FM specialists, and clinical scientists (interviews only) were used to address: 1) Views on the pES service; 2) Capacity and resources involved in offering pES; 3) Awareness, knowledge, and educational needs; and 4) Ambitions and goals for the future. Results: Overall, professionals were positive about the pES service with 77% rating it as Good or Excellent. A number of benefits were reported, including the increased opportunity for receiving actionable results for parental decision-making, improving equity of access to genomic tests and fostering close relationships between FM and genetics departments. Nonetheless, there was evidence that the shift to offering pES in a clinical setting had brought some challenges, such as additional clinic time, administrative processes, perceived lack of autonomy in decision-making regarding pES eligibility and difficulty engaging with peripheral maternity units. Concerns were also raised about the lack of confidence and gaps in genomics knowledge amongst non-genetics professionals - especially midwives. However, the findings also highlighted value in both FM, obstetric and genetics professionals benefiting from further training with a focus on recognising and managing prenatally diagnosed genetic conditions. Conclusion: Healthcare professionals are enthusiastic about the benefits of pES, and through multi-collaborative working, have developed relationships that have contributed to effective communication across specialisms. Although limitations on resources and variation in knowledge about pES have impacted service delivery, professionals were hopeful that improvements to infrastructure and the upskilling of all professionals involved in the pathway would optimise the benefits of pES for both parents and professionals
A restricted spectrum of missense KMT2D variants cause a multiple malformations disorder distinct from Kabuki syndrome
Purpose: To investigate if specific exon 38 or 39 KMT2D missense variants (MVs) cause a condition distinct from Kabuki syndrome type 1 (KS1).
Methods: Multiple individuals, with MVs in exons 38 or 39 of KMT2D that encode a highly conserved region of 54 amino acids flanked by Val3527 and Lys3583, were identified and phenotyped. Functional tests were performed to study their pathogenicity and understand the disease mechanism.
Results: The consistent clinical features of the affected individuals, from seven unrelated families, included choanal atresia, athelia or hypoplastic nipples, branchial sinus abnormalities, neck pits, lacrimal duct anomalies, hearing loss, external ear malformations, and thyroid abnormalities. None of the individuals had intellectual disability. The frequency of clinical features, objective software-based facial analysis metrics, and genome-wide peripheral blood DNA methylation patterns in these patients were significantly different from that of KS1. Circular dichroism spectroscopy indicated that these MVs perturb KMT2D secondary structure through an increased disordered to É‘-helical transition.
Conclusion: KMT2D MVs located in a specific region spanning exons 38 and 39 and affecting highly conserved residues cause a novel multiple malformations syndrome distinct from KS1. Unlike KMT2D haploinsufficiency in KS1, these MVs likely result in disease through a dominant negative mechanism.This article is freely available via Open Access. Click on the Publisher URL to access it via the publisher's site.16-17/10/Newlife - The Charity for Disabled Children
FS/13/32/30069/BHF_/British Heart Foundation/United Kingdom
72160007/Chile's National Commission for Scientific and Technological Research
MR/K011154/1/MRC_/Medical Research Council/United Kingdom
WT_/Wellcome Trust/United Kingdompre-prin
Olaparib in patients with metastatic castration-resistant prostate cancer with DNA repair gene aberrations (TOPARP-B): a multicentre, open-label, randomised, phase 2 trial
Background
Metastatic castration-resistant prostate cancer is enriched in DNA damage response (DDR) gene aberrations. The TOPARP-B trial aims to prospectively validate the association between DDR gene aberrations and response to olaparib in metastatic castration-resistant prostate cancer.
Methods
In this open-label, investigator-initiated, randomised phase 2 trial following a selection (or pick-the-winner) design, we recruited participants from 17 UK hospitals. Men aged 18 years or older with progressing metastatic castration-resistant prostate cancer previously treated with one or two taxane chemotherapy regimens and with an Eastern Cooperative Oncology Group performance status of 2 or less had tumour biopsies tested with targeted sequencing. Patients with DDR gene aberrations were randomly assigned (1:1) by a computer-generated minimisation method, with balancing for circulating tumour cell count at screening, to receive 400 mg or 300 mg olaparib twice daily, given continuously in 4-week cycles until disease progression or unacceptable toxicity. Neither participants nor investigators were masked to dose allocation. The primary endpoint of confirmed response was defined as a composite of all patients presenting with any of the following outcomes: radiological objective response (as assessed by Response Evaluation Criteria in Solid Tumors 1.1), a decrease in prostate-specific antigen (PSA) of 50% or more (PSA50) from baseline, or conversion of circulating tumour cell count (from ≥5 cells per 7·5 mL blood at baseline to <5 cells per 7·5 mL blood). A confirmed response in a consecutive assessment after at least 4 weeks was required for each component. The primary analysis was done in the evaluable population. If at least 19 (43%) of 44 evaluable patients in a dose cohort responded, then the dose cohort would be considered successful. Safety was assessed in all patients who received at least one dose of olaparib. This trial is registered at ClinicalTrials.gov, NCT01682772. Recruitment for the trial has completed and follow-up is ongoing.
Findings
711 patients consented for targeted screening between April 1, 2015, and Aug 30, 2018. 161 patients had DDR gene aberrations, 98 of whom were randomly assigned and treated (49 patients for each olaparib dose), with 92 evaluable for the primary endpoint (46 patients for each olaparib dose). Median follow-up was 24·8 months (IQR 16·7–35·9). Confirmed composite response was achieved in 25 (54·3%; 95% CI 39·0–69·1) of 46 evaluable patients in the 400 mg cohort, and 18 (39·1%; 25·1–54·6) of 46 evaluable patients in the 300 mg cohort. Radiological response was achieved in eight (24·2%; 11·1–42·3) of 33 evaluable patients in the 400 mg cohort and six (16·2%; 6·2–32·0) of 37 in the 300 mg cohort; PSA50 response was achieved in 17 (37·0%; 23·2–52·5) of 46 and 13 (30·2%; 17·2–46·1) of 43; and circulating tumour cell count conversion was achieved in 15 (53·6%; 33·9–72·5) of 28 and 13 (48·1%; 28·7–68·1) of 27. The most common grade 3–4 adverse event in both cohorts was anaemia (15 [31%] of 49 patients in the 300 mg cohort and 18 [37%] of 49 in the 400 mg cohort). 19 serious adverse reactions were reported in 13 patients. One death possibly related to treatment (myocardial infarction) occurred after 11 days of treatment in the 300 mg cohort.
Interpretation
Olaparib has antitumour activity against metastatic castration-resistant prostate cancer with DDR gene aberrations, supporting the implementation of genomic stratification of metastatic castration-resistant prostate cancer in clinical practice
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