67 research outputs found
Exact Multiplicities in the Three-Anyon Spectrum
Using the symmetry properties of the three-anyon spectrum, we obtain exactly
the multiplicities of states with given energy and angular momentum. The
results are shown to be in agreement with the proper quantum mechanical and
semiclassical considerations, and the unexplained points are indicated.Comment: 16 pages plus 3 postscript figures, Kiev Institute for Theoretical
Physics preprint ITP-93-32
A False Start in the Race Against Doping in Sport: Concerns With Cycling’s Biological Passport
Professional cycling has suffered from a number of doping scandals. The sport’s governing bodies have responded by implementing an aggressive new antidoping program known as the biological passport. Cycling’s biological passport marks a departure from traditional antidoping efforts, which have focused on directly detecting prohibited substances in a cyclist’s system. Instead, the biological passport tracks biological variables in a cyclist’s blood and urine over time, monitoring for fluctuations that are thought to indirectly reveal the effects of doping. Although this method of indirect detection is promising, it also raises serious legal and scientific concerns. Since its introduction, the cycling community has debated the reliability of indirect biological-passport evidence and the clarity, consistency, and transparency of its use in proving doping violations. Such uncertainty undermines the legitimacy of finding cyclists guilty of doping based on this indirect evidence alone. Antidoping authorities should address these important concerns before continuing to pursue doping sanctions against cyclists solely on the basis of their biological passports
Treatment of bulky lymph nodes in locally advanced cervical cancer:boosting versus debulking
Objective: Treatment strategies for bulky lymph nodes in patients with locally advanced cervical cancer scheduled for definitive chemoradiation include nodal boosting with radiotherapy, surgical debulking, or both. The aim of this retrospective cohort study was to compare survival and toxicity in patients receiving these treatments and to compare them with a group that received neither form of treatment. Methods: Women diagnosed between January 2009 and January 2017 with International Federation of Gynecology and Obstetrics (FIGO) 2009 stage IB2, IIA2-IVA cervical cancer with lymph nodes ≥1.5 cm without upper limit on pretreatment imaging and treated with definitive chemoradiation were selected from the Netherlands Cancer Registry. Patients were categorized by intention-to-treat strategy: boosting, debulking, or neither treatment, with subgroup analysis for patients receiving both treatments, that is, debulking with boosting. Overall and relapse-free survival outcomes were compared by Kaplan-Meier and Cox regression analyses and toxicity by logistic regression analysis. Results: Of 190 patients, 101 (53%) received only nodal boosting, 31 (16%) debulking alone, 29 (15%) debulking combined with boosting, and 29 (15%) received neither treatment. The 5 year overall and relapse-free survival for the treatment groups were 58%, 45% and 45% (p=0.19), and 47%, 44% and 46% (p=0.87), respectively. Multivariable Cox regression analyses demonstrated no differences in overall and relapse-free survival. Combination of debulking with boosting was associated with decreased overall and relapse-free survival compared with debulking alone (HR 2.47, 95% CI 1.22 to 5.00; and HR 2.37, 95% CI 1.14 to 4.93). Nodal boosting was independently associated with a decreased toxicity risk compared with debulking strategy (OR 0.37, 95% CI 0.16 to 0.83). Conclusions: This study showed no survival benefit from either nodal boosting or debulking strategy in patients with suspicious bulky nodes. Nodal boosting might, however, be associated with less toxicity. Dual treatment with debulking and boosting showed a worse survival outcome because this group probably represents patients with poor prognostic factors
Approximate formula for the ground state energy of anyons in 2D parabolic well
We determine approximate formula for the ground state energy of anyons in 2D
parabolic well which is valid for the arbitrary anyonic factor \nu and number
of particles N in the system. We assume that centre of mass motion energy is
not excluded from the energy of the system. Formula for ground state energy
calculated by variational principle contains logarithmic divergence at small
distances between two anyons which is regularized by cut-off parameter. By
equating this variational formula to the analogous formula of Wu near bosonic
limit (\nu ~ 0)we determine the value of the cut-off and thus derive the
approximate formula for the ground state energy for the any \nu and N. We
checked this formula at \nu=1, when anyons become fermions, for the systems
containing two to thirty particles. We find that our approximate formula has an
accuracy within 6%. It turns out, at the big number N limit the ground state
energy has square root dependence on factor \nu.Comment: 7 page
Type D patients report poorer health status prior to and after cardiac rehabilitation compared to non-type D patients
Background: Type D personality is an emerging risk factor in coronary artery disease (CAD). Cardiac rehabilitation (CR) improves outcomes, but little is known about the effects of CR on Type D patients. Purpose: We examined (1) variability in Type D caseness following CR, (2) Type D as a determinant of health status, and (3) the clinical relevance of Type D as a determinant of health status compared to cardiac history. Methods: CAD patients (n = 368) participating in CR completed the Type D Scale, the Short-Form Health Survey 36 pre- and post-CR, and the Hospital Anxiety and Depression Scale pre-CR, to assess health status and depressive and anxious symptomatology, respectively. Results: The prevalence of Type D decreased from 26.6% to 20.7% (p = 0.012) following CR, but Type D caseness remained stable in 81% of patients. Health status significantly improved following CR [F(1,359) = 17.48, p < 0.001], adjusting for demographic and clinical factors and anxious and depressive symptoms. Type D patients reported poorer health status [F(1,359) = 10.40, p = 0.001], with the effect of Type D being stable over time [F(1,359) = 0.49, p = 0.48]. Patients with a cardiac history benefited less from CR [F(1,359) = 5.76, p = 0.02]. The influence of Type D on health status was larger compared to that for cardiac history, as indicated by Cohen's effect size index. Conclusions: Type D patients reported poorer health status compared to non-Type D patients pre- and post-CR. In the majority of patients, CR did not change Type D caseness, with Type D being associated with a stable and clinically relevant effect on outcome. These high-risk patients should
A second generation cervico-vaginal lavage device shows similar performance as its preceding version with respect to DNA yield and HPV DNA results
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118480.pdf (publisher's version ) (Open Access)BACKGROUND: Attendance rates of cervical screening programs can be increased by offering HPV self-sampling to non-attendees. Acceptability, DNA yield, lavage volumes and choice of hrHPV test can influence effectiveness of the self-sampling procedures and could therefore play a role in recruiting non-attendees. To increase user-friendliness, a frequently used lavage sampler was modified. In this study, we compared this second generation lavage device with the first generation device within similar birth cohorts. METHODS: Within a large self-sampling cohort-study among non-responders of the Dutch cervical screening program, a subset of 2,644 women received a second generation self-sampling lavage device, while 11,977 women, matched for age and ZIP-code, received the first generation model. The second generation device was different in shape, color, lavage volume, and packaging, in comparison to its first generation model. The Cochran's test was used to compare both devices for hrHPV positivity rate and response rate. To correct for possible heterogeneity between age and ZIP codes in both groups the Breslow-Day test of homogeneity was used. A T-test was utilized to compare DNA yields of the obtained material in both groups. RESULTS: Median DNA yields were 90.4 mug/ml (95% CI 83.2-97.5) and 91.1 mug/ml (95% CI 77.8-104.4, p= 0.726) and hrHPV positivity rates were 8.2% and 6.9% (p= 0.419) per sample self-collected by the second - and the first generation of the device (p= 0.726), respectively. In addition, response rates were comparable for the two models (35.4% versus 34.4%, p= 0.654). CONCLUSIONS: Replacing the first generation self-sampling device by an ergonomically improved, second generation device resulted in equal DNA yields, comparable hrHPV positivity rates and similar response rates. Therefore, it can be concluded that the clinical performance of the first and second generation models are similar. Moreover, participation of non-attendees in cervical cancer screening is probably not predominantly determined by the type of self-collection device
Diabetes self-management arrangements in Europe: a realist review to facilitate a project implemented in six countries
Background: Self-management of long term conditions can promote quality of life whilst delivering benefits to the financing of health care systems. However, rarely are the meso-level influences, likely to be of direct relevance to these desired outcomes, systematically explored. No specific international guidelines exist suggesting the features of the most appropriate structure and organisation of health care systems within which to situate self-management approaches and practices. This review aimed to identify the quantitative literature with regard to diabetes self-management arrangements currently in place within the health care systems of six countries (The United Kingdom, The Netherlands, Norway, Spain, Bulgaria, and Greece) and explore how these are integrated into the broader health care and welfare systems in each country.
Methods: The methodology for a realist review was followed. Publications of interest dating from 2000 to 2013 were identified through appropriate MeSH terms by a systematic search in six bibliographic databases. A search diary was maintained and the studies were assessed for their quality and risk of bias.
Results: Following the multi-step search strategy, 56 studies were included in the final review (the majority from the UK) reporting design methods and findings on 21 interventions and programmes for diabetes and chronic disease self-management. Most (11/21, 52%) of the interventions were designed to fit within the context of primary care. The majority (11/21, 52%) highlighted behavioural change as an important goal. Finally, some (5/21, 24%) referred explicitly to Internet-based tools.
Conclusions: This review is based on results which are derived from a total of at least 5,500 individuals residing in the six participating countries. It indicates a policy shift towards patient-centred self-management of diabetes in a primary care context. The professional role of diabetes specialist nurses, the need for multidisciplinary approaches and a focus on patient education emerge as fundamental principles in the design of relevant programmes. Socio-economic circumstances are relevant to the capacity to self-manage and suggest that any gains and progress will be hard to maintain during economic austerity. This realist review should be interpreted within the wider context of a whole systems approach regarding self-care support and chronic illness management
Viruses: incredible nanomachines. New advances with filamentous phages
During recent decades, bacteriophages have been at the cutting edge of new developments in molecular biology, biophysics, and, more recently, bionanotechnology. In particular filamentous viruses, for example bacteriophage M13, have a virion architecture that enables precision building of ordered and defect-free two and three-dimensional structures on a nanometre scale. This could not have been possible without detailed knowledge of coat protein structure and dynamics during the virus reproduction cycle. The results of the spectroscopic studies conducted in our group compellingly demonstrate a critical role of membrane embedment of the protein both during infectious entry of the virus into the host cell and during assembly of the new virion in the host membrane. The protein is effectively embedded in the membrane by a strong C-terminal interfacial anchor, which together with a simple tilt mechanism and a subtle structural adjustment of the extreme end of its N terminus provides favourable thermodynamical association of the protein in the lipid bilayer. This basic physicochemical rule cannot be violated and any new bionanotechnology that will emerge from bacteriophage M13 should take this into account
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