Software-Engineering Process Simulation (SEPS) model

The Software Engineering Process Simulation (SEPS) model is described which was developed at JPL. SEPS is a dynamic simulation model of the software project development process. It uses the feedback principles of system dynamics to simulate the dynamic interactions among various software life cycle development activities and management decision making processes. The model is designed to be a planning tool to examine tradeoffs of cost, schedule, and functionality, and to test the implications of different managerial policies on a project's outcome. Furthermore, SEPS will enable software managers to gain a better understanding of the dynamics of software project development and perform postmodern assessments

Current rectification in a single molecule diode: the role of electrode coupling

We demonstrate large rectification ratios (> 100) in single-molecule junctions based on a metal-oxide cluster (polyoxometalate), using a scanning tunneling microscope (STM) both at ambient conditions and at low temperature. These rectification ratios are the largest ever observed in a single-molecule junction, and in addition these junctions sustain current densities larger than 10^5 A/cm^2. By following the variation of the I-V characteristics with tip-molecule separation we demonstrate unambiguously that rectification is due to asymmetric coupling to the electrodes of a molecule with an asymmetric level structure. This mechanism can be implemented in other type of molecular junctions using both organic and inorganic molecules and provides a simple strategy for the rational design of molecular diodes

Finite element analysis of gradient coil deformation and vibration in NMR microscopy

Resolution degradation due to gradient coil deformation and vibration in NMR microscopy is investigated using finite element analysis. From the analysis, deformations due to the Lorentz force can be as large as 1-10 μm depending on the gradient strength and coil frame material. Thus, these deformations can be one of the major resolution limiting factors in NMR microscopy. Coil vibration, which depends on the input current waveform and resolution degradation due to time-variant deformation and time-invariant deformation are investigated by numerical simulations

Serological and Molecular Identification of Brucella spp. in Pigs from Cairo and Giza Governorates, Egypt

Brucellosis is considered as endemic disease of animals and humans since thousands of years in Egypt. However, brucellosis in pigs has never been reported in Egypt. Thus, serological and molecular assays were applied to detect anti-Brucella antibodies and DNA in serum samples collected from pigs. In total 331 blood samples collected from male and female pigs at slaughterhouses of Cairo and Giza governorates were investigated using Brucella c- and i-ELISA and Brucella real-time PCR. Anti-Brucella antibodies were detected in 16 (4.83%) and 36 (10.8%) sera by i-ELISA and c-ELISA, respectively. Brucella DNA was detected in 10 (3.02%) seropositive samples and identified as Brucella melitensis (7/10) and Brucella suis (3/10). A higher prevelance was found in boars. This is the first study investigating pig brucellosis in Egypt. The results of this study will raise awareness for brucellosis in these farm animals and will help to develop effective control strategies

Universality in movie rating distributions

In this paper histograms of user ratings for movies (1,...,10) are analysed. The evolving stabilised shapes of histograms follow the rule that all are either double- or triple-peaked. Moreover, at most one peak can be on the central bins 2,...,9 and the distribution in these bins looks smooth `Gaussian-like' while changes at the extremes (1 and 10) often look abrupt. It is shown that this is well approximated under the assumption that histograms are confined and discretised probability density functions of L\'evy skew alpha-stable distributions. These distributions are the only stable distributions which could emerge due to a generalized central limit theorem from averaging of various independent random avriables as which one can see the initial opinions of users. Averaging is also an appropriate assumption about the social process which underlies the process of continuous opinion formation. Surprisingly, not the normal distribution achieves the best fit over histograms obseved on the web, but distributions with fat tails which decay as power-laws with exponent -(1+alpha) (alpha=4/3). The scale and skewness parameters of the Levy skew alpha-stable distributions seem to depend on the deviation from an average movie (with mean about 7.6). The histogram of such an average movie has no skewness and is the most narrow one. If a movie deviates from average the distribution gets broader and skew. The skewness pronounces the deviation. This is used to construct a one parameter fit which gives some evidence of universality in processes of continuous opinion dynamics about taste.Comment: 8 pages, 5 figures, accepted for publicatio

Anxious/depressed symptoms are related to microstructural maturation of white matter in typically developing youths

AbstractThere are multiple recent reports of an association between anxious/depressed (A/D) symptomatology and the rate of cerebral cortical thickness maturation in typically developing youths. We investigated the degree to which anxious/depressed symptoms are tied to age-related microstructural changes in cerebral fiber pathways. The participants were part of the NIH MRI Study of Normal Brain Development. Child Behavior Checklist A/D scores and diffusion imaging were available for 175 youths (84 males, 91 females; 241 magnetic resonance imagings) at up to three visits. The participants ranged from 5.7 to 18.4 years of age at the time of the scan. Alignment of fractional anisotropy data was implemented using FSL/Tract-Based Spatial Statistics, and linear mixed model regression was carried out using SPSS. Child Behavior Checklist A/D was associated with the rate of microstructural development in several white matter pathways, including the bilateral anterior thalamic radiation, bilateral inferior longitudinal fasciculus, left superior longitudinal fasciculus, and right cingulum. Across these pathways, greater age-related fractional anisotropy increases were observed at lower levels of A/D. The results suggest that subclinical A/D symptoms are associated with the rate of microstructural development within several white matter pathways that have been implicated in affect regulation, as well as mood and anxiety psychopathology.</jats:p

Nuclear Medium Effects in the Relativistic Treatment of Quasifree Electron Scattering

Non-relativistic reduction of the S-matrix for the quasifree electron scattering process $A\left(~e, e'p~\right)A-1$ is studied in order to understand the source of differences between non-relativistic and relativistic models. We perform an effective Pauli reduction on the relativistic expression for the S-matrix in the one-photon exchange approximation. The reduction is applied to the nucleon current only; the electrons are treated fully relativistically. An expansion of the amplitude results in a power series in the nuclear potentials. The series is found to converge rapidly only if the nuclear potentials are included in the nuclear current operator. The results can be cast in a form which reproduces the non-relativistic amplitudes in the limit that the potentials are removed from the nuclear current operator. Large differences can be found between calculations which do and do not include the nuclear potentials in the different orders of the nuclear current operator. In the high missing momentum region we find that the non-relativistic calculations with potentials included in the nuclear current up to second order give results which are close to those of the fully relativistic calculation. This behavior is an indication of the importance of the medium modifications of the nuclear currents in this model, which are naturally built into the relativistic treatment of the reaction.Comment: Latex, 26 pages including 5 uuencoded postscript figures. accepted for publication in Phys. Rev. C

Oral progesterone for the prevention of recurrent preterm birth: systematic review and metaanalysis

Objective The purpose of this study was to perform a systematic review and metaanalysis of randomized controlled trials on oral progesterone compared with placebo or other interventions for preterm birth prevention in singleton pregnancies with previous spontaneous preterm birth. The primary outcome was preterm birth at <37 weeks gestation; the secondary outcomes included preterm birth rate at <34 weeks gestation, neonatal morbidity/death, and maternal side-effects. Study Searches were performed in PubMed, Scopus, ClinicalTrials.gov, PROSPERO, EMBASE, and the Cochrane Register with the use of a combination of words related to “preterm birth,” “preterm delivery,” “progesterone,” “progestogens,” and “oral” from inception of each database to April 2018. Additionally, systematic reviews on progesterone for preterm birth prevention that were identified in our search were also reviewed for additional studies. We included all randomized trials of asymptomatic singleton gestations with previous spontaneous singleton preterm birth that had been randomized to prophylactic treatment with oral progesterone vs placebo, no treatment, or other preterm birth intervention. Exclusion criteria included quasirandomized trials, trials that involved women with preterm labor/membrane rupture at the time of randomization or multiple gestations. Study Appraisal and Synthesis Methods The risk of bias and quality of evidence were assessed for each study. All analyses were done with an intention-to-treat approach. The primary outcome was incidence of preterm birth at 30% was used to identify heterogeneity. Results The search strategy identified 79 distinct studies. Three trials on oral progesterone vs placebo (involved 386 patients: 196 in oral progesterone and 190 in placebo) met the inclusion criteria; there were no studies on oral progesterone vs other intervention that met inclusion criteria. Metaanalysis demonstrated a significantly decreased risk of preterm birth at <37 weeks gestation (42% vs 63%; P=.0005; relative risk, 0.68; 95% confidence interval, 0.55–0.84), preterm birth at <34 weeks gestation (29% vs 53%; P<.00001; relative risk, 0.55; 95% confidence interval, 0.43–0.71), and increased gestational age of delivery (mean difference, 1.71 weeks; 95% confidence interval, 1.11–2.30) with oral progesterone compared with placebo. There was a significantly lower rate of perinatal death (5% vs 17%; P=.001; relative risk 0.32; 95% confidence interval, 0.16–0.63), neonatal intensive care admission (relative risk, 0.39; 95% confidence interval, 0.25–0.61), respiratory distress syndrome (relative risk, 0.21; 95% confidence interval, 0.05–0.93), and higher birthweight (mean difference, 435.06 g; 95% confidence interval, 324.59–545.52) with oral progesterone. There was a higher rate of maternal adverse effects with oral progesterone that included dizziness (relative risk, 2.95; 95% confidence interval, 1.47–5.90), somnolence (relative risk, 2.06; 95% confidence interval, 1.29–3.30), and vaginal dryness (relative risk, 2.37; 95% confidence interval, 1.10–5.11); no serious adverse effects were noted. Conclusion Oral progesterone appears to be effective for the prevention of recurrent preterm birth and a reduction in perinatal morbidity and mortality rates in asymptomatic singleton gestations with a history of previous spontaneous preterm birth compared with placebo. There were also increased adverse effects with oral progesterone therapy compared with placebo, although none were serious. Further randomized study on oral progesterone compared with other established therapies for the prevention of recurrent preterm birth are warranted

The Impact of the Extent of Lymphadenectomy on Oncologic Outcomes in Patients Undergoing Radical Cystectomy for Bladder Cancer : A Systematic Review

Copyright © 2014 European Association of Urology. Published by Elsevier B.V. All rights reserved.Peer reviewedPostprin