131 research outputs found

    Challenges of Profile Likelihood Evaluation in Multi-Dimensional SUSY Scans

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    Statistical inference of the fundamental parameters of supersymmetric theories is a challenging and active endeavor. Several sophisticated algorithms have been employed to this end. While Markov-Chain Monte Carlo (MCMC) and nested sampling techniques are geared towards Bayesian inference, they have also been used to estimate frequentist confidence intervals based on the profile likelihood ratio. We investigate the performance and appropriate configuration of MultiNest, a nested sampling based algorithm, when used for profile likelihood-based analyses both on toy models and on the parameter space of the Constrained MSSM. We find that while the standard configuration is appropriate for an accurate reconstruction of the Bayesian posterior, the profile likelihood is poorly approximated. We identify a more appropriate MultiNest configuration for profile likelihood analyses, which gives an excellent exploration of the profile likelihood (albeit at a larger computational cost), including the identification of the global maximum likelihood value. We conclude that with the appropriate configuration MultiNest is a suitable tool for profile likelihood studies, indicating previous claims to the contrary are not well founded.Comment: 21 pages, 9 figures, 1 table; minor changes following referee report. Matches version accepted by JHE

    Multi-Criteria Evaluation of Quality of Exisiting Urban Parks in Dhaka City - Towards Achieving Livable City

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    Qualitative and quantitative assessment of the quality of major parks in mega city Dhaka have been conducted. Four incommensurate factors: environment, safety and security, landscape and aesthetic value have been considered to qualitatively and quantitatively assesses the quality of the parks. From qualitative analysis it is found that, some parks (located in highly classified residential area of the city) are superior in safety and security and landscape design whereas other parks (located remote from residential area) are inferior in safety and security and environmental factor. It is necessary to address factors of each park lacking behind to ensure better quality of parks. To quantitatively assess the quality of parks, we formulated a new index value calculation to rank all parks in terms of all factors. It is found that the quality of all the parks are dispersed. In addition, investigation of universal accessibility of the parks and direct park user’s opinion has been accumulated to supports findings of this analysis. Based on the major findings of this study a number of recommendations have been provided for the improvement of the quality of parks in Dhaka city such as involvement of local community and establishment of office for the park authority inside the park can be helpful in the quality maintenance of the parks. The findings of this paper can enhance the existing knowledge of city planners a step forward with a-priori knowledge to ensure quality of parks in further city planning. DOI: http://dx.doi.org/10.3126/ije.v3i3.11058 International Journal of Environment Vol.3(3) 2014: 1-15</jats:p

    Novel facultative Methylocella strains are active methane consumers at terrestrial natural gas seeps

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    Natural gas seeps contribute to global climate change by releasing substantial amounts of the potent greenhouse gas methane and other climate-active gases including ethane and propane to the atmosphere. However, methanotrophs, bacteria capable of utilising methane as the sole source of carbon and energy, play a significant role in reducing the emissions of methane from many environments. Methylocella-like facultative methanotrophs are a unique group of bacteria that grow on other components of natural gas (i.e. ethane and propane) in addition to methane but a little is known about the distribution and activity of Methylocella in the environment. The purposes of this study were to identify bacteria involved in cycling methane emitted from natural gas seeps and, most importantly, to investigate if Methylocella-like facultative methanotrophs were active utilisers of natural gas at seep sites

    DESIGN AND PERFORMANCE OF A 300-WATT HELICAL TYPE H-ROTOR WIND TURBINE

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    The Helical Type H-rotor turbine is a modification of the Darrieus turbine by Alexander Gorlov to improve the design of the H-Darrieus so the turbine can self-starting in low wind speed conditions. The purpose of this study is to analyze the pitch angle (5°, 0°, and -5°) when using the symmetrical airfoil (NACA 0018) on the performance of coefficient of power (CP), tip speed ratio (TSR) and coefficient of torque (CT) produced by Helical Type H-rotor turbine. The method used in this research is experimental investigation using wind tunnel.  The Helical Type H-rotor wind turbine is subjected to wind speed of 6 m/s. The results obtained show that the use of 0° pitch angle produces better CP, TSR and CT values than other pitch angles due to the angle of attack produced. this is due to the 0° pitch angle produces an angle of attack that is able to make a more optimal lift force on the turbine blade. At 0° pitch angle the CP value is 0.0337, TSR value is 1.5073 and CT value is 0.0224. While wind turbine that use -5° pitch angle produce better performance than wind turbine that use 5° pitch angle. However, the performance value of both (-5° and 5° pitch angle) is still below the wind turbine with 0° pitch angle

    Gene probing reveals the widespread distribution, diversity and abundance of isoprene-degrading bacteria in the environment

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    Background: Approximately 500 Tg of isoprene are emitted to the atmosphere annually, an amount similar to that of methane, and despite its significant effects on the climate, very little is known about the biological degradation of isoprene in the environment. Isolation and characterisation of isoprene degraders at the molecular level has allowed the development of probes targeting isoA encoding the α-subunit of the isoprene monooxygenase. This enzyme belongs to the soluble diiron centre monooxygenase family and catalyses the first step in the isoprene degradation pathway. The use of probes targeting key metabolic genes is a successful approach in molecular ecology to study specific groups of bacteria in complex environments. Here, we developed and tested a novel isoA PCR primer set to study the distribution, abundance, and diversity of isoprene degraders in a wide range of environments. Results: The new isoA probes specifically amplified isoA genes from taxonomically diverse isoprene-degrading bacteria including members of the genera Rhodococcus, Variovorax, and Sphingopyxis. There was no cross-reactivity with genes encoding related oxygenases from non-isoprene degraders. Sequencing of isoA amplicons from DNA extracted from environmental samples enriched with isoprene revealed that most environments tested harboured a considerable variety of isoA sequences, with poplar leaf enrichments containing more phylogenetically diverse isoA genes. Quantification by qPCR using these isoA probes revealed that isoprene degraders are widespread in the phyllosphere, terrestrial, freshwater and marine environments. Specifically, soils in the vicinity of high isoprene-emitting trees contained the highest number of isoprene-degrading bacteria. Conclusion: This study provides the molecular ecology tools to broaden our knowledge of the distribution, abundance and diversity of isoprene degraders in the environment, which is a fundamental step necessary to assess the impact that microbes have in mitigating the effects of this important climate-active gas

    Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study.

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    Background: Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery. Methods: This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation. Results: A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14·2 per cent (646 of 4544) and the 30-day mortality rate was 1·8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7·61, 95 per cent c.i. 4·49 to 12·90; P < 0·001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0·65). Discussion: Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability

    Guyon's canal syndrome due to tortuous ulnar artery with DeQuervain stenosing tenosynovitis, ligamentous injuries and dorsal intercalated segmental instability syndrome, a rare presentation: a case report

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    The Guyon's canal syndrome is a well known clinical entity and may have significant impact on patient's quality of life. We report a case of 43-year-old male who presented with complaints of pain and numbness in right hand and difficulty in writing for past one month. On imaging diagnosis of Guyon's canal syndrome because of tortuous ulnar artery was made with additional findings of DeQuervain's stenosing tenosynovitis and dorsal intercalated segmental instability syndrome with ligamentous injury and subsequently these were confirmed on surgery

    A Possible Role for Metallic Ions in the Carbohydrate Cluster Recognition Displayed by a Lewis Y Specific Antibody

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    BACKGROUND:Lewis Y (Le(y)) is a blood group-related carbohydrate that is expressed at high surface densities on the majority of epithelial carcinomas and is a promising target for antibody-based immunotherapy. A humanized Le(y)-specific antibody (hu3S193) has shown encouraging safety, pharmacokinetic and tumor-targeting properties in recently completed Phase I clinical trials. METHODOLOGY/PRINCIPAL FINDINGS:We report the three-dimensional structures for both the free (unliganded) and bound (Le(y) tetrasaccharide) hu3S193 Fab from the same crystal grown in the presence of divalent zinc ions. There is no evidence of significant conformational changes occurring in either the Le(y) carbohydrate antigen or the hu3S193 binding site, which suggests a rigid fit binding mechanism. In the crystal, the hu3S193 Fab molecules are coordinated at their protein-protein interface by two zinc ions and in solution aggregation of Fab can be initiated by zinc, but not magnesium ions. Dynamic light scattering revealed that zinc ions could initiate a sharp transition from hu3S193 Fab monomers to large multimeric aggregates in solution. CONCLUSIONS/SIGNIFICANCE:Zinc ions can mediate interactions between hu3S193 Fab in crystals and in solution. Whether metallic ion mediated aggregation of antibody occurs in vivo is not known, but the present results suggest that similar clustering mechanisms could occur when hu3S193 binds to Le(y) on cells, particularly given the high surface densities of antigen on the target tumor cells

    Once-Weekly Insulin Efsitora Alfa Versus Once Daily Insulin in Patients With Type 2 Diabetes: A Systematic Review and Meta-Analysis

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    \ua9 2025 The Author(s). Endocrinology, Diabetes &amp; Metabolism published by John Wiley &amp; Sons Ltd.Background: Once-daily basal insulin is widely used in the management of type 2 diabetes, but poor adherence to daily injections often impairs glycaemic control. Once-weekly efsitora alfa may overcome these limitations, but pooled data assessing its comparative efficacy and safety remain limited. Methods: PubMed/MEDLINE, Google Scholar, and the Cochrane Library were searched up to July 2025 for RCTs comparing once-weekly efsitora with once daily insulin in adults with T2D. Weighted mean differences (MDs), odds ratios (ORs), and risk ratios (RRs) were pooled using a random-effects model, and results were reported with 95% confidence intervals. Results: Six RCTs comprising 3967 participants were included. There were no significant differences between once-weekly efsitora and daily insulin in change in HbA1c (MD –0.04; 95% CI –0.10 to 0.02; p = 0.15), change in fasting plasma glucose (MD 1.94 mg/dL; 95% CI –2.98 to 6.86; p = 0.44), proportion of patients achieving HbA1c &lt; 7%, change in body weight, or time below range. Efsitora was associated with an increase in time in range (MD 0.80 percentage points; 95% CI 0.09 to 1.52; p = 0.03) and a reduction in time above range (MD –1.45 percentage points; 95% CI –2.87 to −0.02; p = 0.05). The risk of treatment-emergent adverse events (TEAEs) was higher with efsitora (RR 1.13; 95% CI 1.05 to 1.20; p = 0.0004), whereas serious adverse events, hypersensitivity reactions, injection-site reactions, and hypoglycaemia events were comparable between the two groups. Conclusion: Once-weekly efsitora provides comparable glycaemic control and improved time-in-range compared to daily insulin, although with a higher rate of TEAEs
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