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A corrected formula for uncertainty in estimations of gestational age from fetal head circumference measurements
Numerous publications over recent years have proposed methods for estimation of gestational age (GA) from fetal measurements including biparietal diameter, head circumference, crown-rump length and others. The manuscript of Altman and Chitty1 presented statistical modelling of data from 663 fetuses to define charts and tables for pregnancy dating based upon such measures. The resulting outputs are tables of mean GA estimates based upon each measurement, each with a corresponding standard deviation that encompasses the uncertainty in the prediction. We here address an erroneous result in the appendix of this work, associated with the uncertainty in GA prediction based upon derived head circumference measurements
Checklist of British and Irish Hymenoptera - Braconidae
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The attached file is the published version of the article.NHM Repositor
In Vivo validation of a bioinformatics based tool to identify reduced replication capacity in HIV-1.
Although antiretroviral drug resistance is common in treated HIV infected individuals, it is not a consistent indicator of HIV morbidity and mortality. To the contrary, HIV resistance-associated mutations may lead to changes in viral fitness that are beneficial to infected individuals. Using a bioinformatics-based model to assess the effects of numerous drug resistance mutations, we determined that the D30N mutation in HIV-1 protease had the largest decrease in replication capacity among known protease resistance mutations. To test this in silico result in an in vivo environment, we constructed several drug-resistant mutant HIV-1 strains and compared their relative fitness utilizing the SCID-hu mouse model. We found HIV-1 containing the D30N mutation had a significant defect in vivo, showing impaired replication kinetics and a decreased ability to deplete CD4+ thymocytes, compared to the wild-type or virus without the D30N mutation. In comparison, virus containing the M184V mutation in reverse transcriptase, which shows decreased replication capacity in vitro, did not have an effect on viral fitness in vivo. Thus, in this study we have verified an in silico bioinformatics result with a biological assessment to identify a unique mutation in HIV-1 that has a significant fitness defect in vivo
Exact solutions for supersymmetric stationary black hole composites
Four dimensional N=2 supergravity has regular, stationary, asymptotically
flat BPS solutions with intrinsic angular momentum, describing bound states of
separate extremal black holes with mutually nonlocal charges. Though the
existence and some properties of these solutions were established some time
ago, fully explicit analytic solutions were lacking thus far. In this note, we
fill this gap. We show in general that explicit solutions can be constructed
whenever an explicit formula is known in the theory at hand for the
Bekenstein-Hawking entropy of a single black hole as a function of its charges,
and illustrate this with some simple examples. We also give an example of
moduli-dependent black hole entropy.Comment: 13 pages, 1 figur
J-Class Abelian Semigroups of Matrices on C^n and Hypercyclicity
We give a characterization of hypercyclic finitely generated abelian
semigroups of matrices on C^n using the extended limit sets (the J-sets).
Moreover we construct for any n\geq 2 an abelian semigroup G of GL(n;C)
generated by n + 1 diagonal matrices which is locally hypercyclic but not
hypercyclic and such that JG(e_k) = C^n for every k = 1; : : : ; n, where (e_1;
: : : ; e_n) is the canonical basis of C^n. This gives a negative answer to a
question raised by Costakis and Manoussos.Comment: 10 page
Changes over time in socioeconomic inequalities in breast and rectal cancer survival in England and Wales during a 32-year period (1973-2004): the potential role of health care.
BACKGROUND: Socioeconomic inequalities in cancer survival are well documented but they vary for different cancers and over time. Reasons for these differences are poorly understood. PATIENTS AND METHODS: For England and Wales, we examined trends in socioeconomic survival inequalities for breast cancer in women and rectal cancer in men during the 32-year period 1973-2004. We used a theoretical framework based on Victora's 'inverse equity' law, under which survival inequalities could change with the advent of successive new treatments, of varying effectiveness, which are disseminated with different speed among patients of different socioeconomic groups. We estimated 5-year relative survival for patients of different deprivation quintiles and examined trends in survival inequalities in light of major treatment innovations. RESULTS: Inequalities in breast cancer survival (921,611 cases) narrowed steadily during the study (from -10% to -6%). In contrast, inequalities in rectal cancer survival (187,104 cases) widened overall (form -5% to -11%) with fluctuating periods of narrowing inequality. CONCLUSIONS: Trends in socioeconomic differences in tumour or patient factors are unlikely explanations of observed changes over time in survival inequalities. The sequential introduction into clinical practice of new treatments of progressively smaller incremental benefit may partly explain the reduction in inequality in breast cancer survival
Assessment of Metabolic Parameters For Autism Spectrum Disorders
Autism is a brain development disorder that first appears during infancy or childhood, and generally follows a steady course without remission. Impairments result from maturation-related changes in various systems of the brain. Autism is one of the five pervasive developmental disorders (PDD), which are characterized by widespread abnormalities of social interactions and communication, and severely restricted interests and highly repetitive behavior. The reported incidence of autism spectrum disorders (ASDs) has increased markedly over the past decade. The Centre for Disease Control and Prevention has recently estimated the prevalence of ASDs in the United States at approximately 5.6 per 1000 (1 of 155 to 1 of 160) children. Several metabolic defects, such as phenylketonuria, are associated with autistic symptoms. In deciding upon the appropriate evaluation scheme a clinician must consider a host of different factors. The guidelines in this article have been developed to assist the clinician in the consideration of these factors
Edge Elimination in TSP Instances
The Traveling Salesman Problem is one of the best studied NP-hard problems in
combinatorial optimization. Powerful methods have been developed over the last
60 years to find optimum solutions to large TSP instances. The largest TSP
instance so far that has been solved optimally has 85,900 vertices. Its
solution required more than 136 years of total CPU time using the
branch-and-cut based Concorde TSP code [1]. In this paper we present graph
theoretic results that allow to prove that some edges of a TSP instance cannot
occur in any optimum TSP tour. Based on these results we propose a
combinatorial algorithm to identify such edges. The runtime of the main part of
our algorithm is for an n-vertex TSP instance. By combining our
approach with the Concorde TSP solver we are able to solve a large TSPLIB
instance more than 11 times faster than Concorde alone
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