13 research outputs found

    A New Beta Power Generator for Continuous Random Variable: Features and Inference to Model Asymmetric Data

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    Statistical methodologies have broad applications in sports and other exercise sciences. These methods can be used to predict the winning probability of a team or individual in a match. Due to the applicability of the statistical methods in sports, this paper introduces a new method of obtaining statistical distributions. The new method is called a novel beta power-L family of distributions. Some mathematical characteristics of the new family are obtained. Based on the novel beta power-L family, a special model, namely, a novel beta power Weibull model is studied. Finally, the applicability/usefulness of the novel beta power Weibull distribution is shown by analyzing the time-to-even data taken from different football matches during 1964-2018. The data consist of seventy-eight observations and is representing the waiting time duration of the fastest goal scored ever in the history of football. The fitting results of the novel beta power Weibull distribution are compared with other models. Based on three model selection criteria, it is observed that the proposed novel beta power Weibull model provides a close fit to the waiting time data

    Periodic trends and easy estimation of relative stabilities in 11-vertex nido-p-block-heteroboranes and -borates

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    Density functional theory computations were carried out for 11-vertex nido-p-block-hetero(carba)boranes and -borates containing silicon, germanium, tin, arsenic, antimony, sulfur, selenium and tellurium heteroatoms. A set of quantitative values called “estimated energy penalties” was derived by comparing the energies of two reference structures that differ with respect to one structural feature only. These energy penalties behave additively, i.e., they allow us to reproduce the DFT-computed relative stabilities of 11-vertex nido-heteroboranes in general with good accuracy and to predict the thermodynamic stabilities of unknown structures easily. Energy penalties for neighboring heteroatoms (HetHet and HetHet′) decrease down the group and increase along the period (indirectly proportional to covalent radii). Energy penalties for a five- rather than four-coordinate heteroatom, [Het5k(1) and Het5k(2)], generally, increase down group 14 but decrease down group 16, while there are mixed trends for group 15 heteroatoms. The sum of HetHet′ energy penalties results in different but easily predictable open-face heteroatom positions in the thermodynamically most stable mixed heterocarbaboranes and -borates with more than two heteroatoms

    Structural basis of metallo-β-lactamase, serine-β-lactamase and penicillin-binding protein inhibition by cyclic boronates

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    β-Lactamases enable resistance to almost all β-lactam antibiotics. Pioneering work revealed that acyclic boronic acids can act as ‘transition state analogue’ inhibitors of nucleophilic serine enzymes, including serine-β-lactamases. Here we report biochemical and biophysical analyses revealing that cyclic boronates potently inhibit both nucleophilic serine and zinc-dependent β-lactamases by a mechanism involving mimicking of the common tetrahedral intermediate. Cyclic boronates also potently inhibit the non-essential penicillin-binding protein PBP 5 by the same mechanism of action. The results open the way for development of dual action inhibitors effective against both serine- and metallo-β-lactamases, and which could also have antimicrobial activity through inhibition of PBPs

    An SNF2 Protein Associated with Nuclear RNA Silencing and the Spread of a Silencing Signal between Cells in Arabidopsis[W][OA]

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    The silencing phenotype in Arabidopsis thaliana lines with an inverted repeat transgene under the control of a phloem-specific promoter was manifested in regions around veins due to a mobile signal of silencing. Genetic analysis implicates RNA-DEPENDENT RNA POLYMERASE2 (RDR2) and an RNA polymerase IVa subunit gene (NRPD1a) in the signaling mechanism. We also identified an SNF2 domain–containing protein (CLASSY1) that acts together with RDR2 and NRPD1a in the spread of transgene silencing and in the production of endogenous 24-nucleotide short interfering RNAs (siRNAs). Cytochemical analysis indicates that CLASSY1 may act in the nucleus with NRPD1a and RDR2 in the upstream part of RNA silencing pathways that generate a double-stranded RNA substrate for Dicer-like (DCL) nucleases. DCL3 and ARGONAUTE4 act in a downstream part of the pathway, leading to endogenous 24-nucleotide siRNA production, but are not required for intercellular signaling. From genetic analysis, we conclude that another downstream part of the pathway associated with intercellular signaling requires DCL4 and at least one other protein required for 21-nucleotide trans-acting siRNAs. We interpret the effect of polymerase IVa and trans-acting siRNA pathway mutations in terms of a modular property of RNA silencing pathways

    An SNF2 Protein Associated with Nuclear RNA Silencing and the Spread of a Silencing Signal between Cells in Arabidopsis[W][OA]

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    The silencing phenotype in Arabidopsis thaliana lines with an inverted repeat transgene under the control of a phloem-specific promoter was manifested in regions around veins due to a mobile signal of silencing. Genetic analysis implicates RNA-DEPENDENT RNA POLYMERASE2 (RDR2) and an RNA polymerase IVa subunit gene (NRPD1a) in the signaling mechanism. We also identified an SNF2 domain–containing protein (CLASSY1) that acts together with RDR2 and NRPD1a in the spread of transgene silencing and in the production of endogenous 24-nucleotide short interfering RNAs (siRNAs). Cytochemical analysis indicates that CLASSY1 may act in the nucleus with NRPD1a and RDR2 in the upstream part of RNA silencing pathways that generate a double-stranded RNA substrate for Dicer-like (DCL) nucleases. DCL3 and ARGONAUTE4 act in a downstream part of the pathway, leading to endogenous 24-nucleotide siRNA production, but are not required for intercellular signaling. From genetic analysis, we conclude that another downstream part of the pathway associated with intercellular signaling requires DCL4 and at least one other protein required for 21-nucleotide trans-acting siRNAs. We interpret the effect of polymerase IVa and trans-acting siRNA pathway mutations in terms of a modular property of RNA silencing pathways

    Incidence, trends and morphology of ovarian cancer in Karachi (1995-2002).

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    Introduction:Cancer ovary is the third most common malignancy diagnosed in women in Karachi, a moderate to high risk region for the disease. Materials and Methods: Three hundred and thirty seven cases of ovarian cancer registered at the Karachi Cancer Registry for the years 1995-2002 were reviewed. Results: The age- standardized incidence rate (ASR) world per 100,000, crude incidence rate per 100,000 (CIR) and frequency of ovarian malignancies in 1995-1997 were 10.9, 5.9 and 6.2% respectively. Corresponding figures for 1998-2002 were 8.1, 5.1 and 4.8%. The mean age at presentation in 1995-1997 was 45.7 years (95%CI 42.9, 48.4, SD∓15.9), range 95 (3 to 98) years and in 1998-2002 it was 45.0 years (95%CI 42.8, 47.3, SD16.1), range 79 (3 to 82) years. Eleven (3.3%) cases of childhood cancers, 13 (3.9%) adolescent cases, 126 (37.4%) reproductive age (20-44 years) and 187 (55.5%) cases in the 45+ age group were registered. Epithelial malignancies were the most common cancers above the age of 20 years (78.4%), the commonest amongst these was serous adenocarcinoma (33.3%). Germ cell tumors were more common (5.6%) in children and adolescents. Microscopic confirmation was 99.0%. Presentation was of a moderately differentiated (grade 2) malignancy with a regional or distant spread of disease in three fourths of the cases. Conclusions: The incidence of cancer ovary, though stable in Karachi, involves a relatively younger age group with a strong family history in a fourth of the cases. The disease presents at an advanced stage. An ageing population over time may translate into a higher incidence of ovarian cancer. The current incidence of cancer ovary in Karachi is an enigma and belies reproductive protective factors. Studies focused on the genetic risk factors in this population are recommended

    Patho-epidemiology of Cancer Cervix in Karachi South

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    Introduction: The present study was conducted with the objective of examining descriptive epidemiological and pathological characteristics of cancer cervix in Karachi South, an all urban district population of Karachi, Pakistan. Methodology: A total of 74 cases of cancer cervix, ICD-10 (International Classification of Diseases 10th Revision) category C53 were registered at the Karachi Cancer Registry, for Karachi South, during a 3 year period, 1st January, 1995 to 31st December 1997. Results: The age standardized incidence rate (ASR) world andcrude incidence rate (CIR) per 100,000 were 6.81 (5.2, 8.43) and 3.22 (2.49 to 3.96). Cancer cervix accounted for approximately 3.6% of all cancers in females and was the sixth malignancy in hierarchy. The mean age of the cancer cases was 53.27 years [standard deviation (SD) 11.6; 95% confidence interval (CI) 50.58, 55.96; range(R) 32-85 years)]. The distribution by religion was Muslims (90.5%), Christians (8.1%) and Hindus (1.4%). There were no cases reported in Parsees. The frequency distribution by ethnicity was Urdu speaking Mohajirs (20.3%), Punjabis (17.6%), Gujrati speaking Mohajirs (4.1%), memon Mohajirs (8.1%), Sindhis (10.8%), Baluchs (8.1%), Pathans (5.4%) and Afghan migrants (2.7%). The ethnicity was not known in approximately a fourth (23.0%) of the cases.The socio-economic distribution was 27.0% financially deprived class, 24.4% lower middle class and 48.7% upper middle and affluent classes. The majority of the women were married (86.5%); a smaller number were unmarried (2.7%) or widows (10.8%). The age-specific curves showed a gradual increase in risk from the fourth up till the seventh decade, followed by an actual apparent decrease in risk after 64 years of age. The peak incidence was observed in the 60-64 year age group. The morphological categorization was squamous cell carcinoma (86.5%), adenocarcinoma (10.9%) and adenosquamous carcinoma (2.6%). The majority of cases presented with moderately differentiated or grade 2 lesions (45.9%). There were no in-situ cases. Approximately half the cancers (58.1%) had spread regionally and 8.1% to a distant site at the time of diagnosis. Odds ratios (OR) were calculated for socioeconomic residential categories, religion, ethnicity, age groups and education. The OR for socioeconomic residential categories ranged between 0.69 and 2.9 with a marginally higher risk in the lower [OR 2.09 (95% CI .97; 4.49)] and lower middle class [OR 2.08 (95%CI 0.95; 4.58)]. Hindus [OR 1.2 (95% CI 0.18; 2.2)] had a slightly higher risk then the Muslims [OR 0.14 (95% CI 0.17; 1.2)]. A higher risk was also observed for Christians [OR 7.76 (95% CI 1.74; 34.5)]. Conclusion: The incidence of cervical cancer in Karachi South (1995-97) reflects a low risk population with a late presentation and a high stage disease at presentation. It is suggested that cervical screening if implemented should focus on once a life time methodology involving 36-45 year old women. This should be combined with HPV vaccination for the young and public health education for all. A regular cervical screening program would require mobilization of considerable financial, structural and human resources along with training for personnel. This may burden the already stretched health resources of a developing country
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