8,807 research outputs found
Space-mapping techniques applied to the optimization of a safety isolating transformer
Space-mapping optimization techniques allow to allign low-fidelity and high-fidelity models in order to reduce the computational time and increase the accuracy of the solution. The main idea is to build an approximate model from the difference of response between both models. Therefore the optimization process is computed on the surrogate model. In this paper, some recent approaches of space-mapping techniques such as agressive-space-mapping, output-mapping and manifold-mapping algorithms are applied to optimize a safety insulating transformer. The electric, magnetic and thermal phenomena of the device are modeled by an analytical model and a 3D finite element model. It is considered as a benchmark for multi-level optimization to test different algorithms
Addressing multiple modifiable risks through structured community-based Learning Clubs to improve maternal and infant health and infant development in rural Vietnam: protocol for a parallel group cluster randomised controlled trial
Introduction: Optimal early childhood development is an international priority. Risks during pregnancy and early childhood have lasting effects because growth is rapid. We will test whether a complex intervention addressing multiple modifiable risks: maternal nutrition, mental health, parenting capabilities, infant health and development and gender-based violence, is effective in reducing deficient cognitive development among children aged two in rural Vietnam. Methods and analysis: The Learning Clubs intervention is a structured programme combining perinatal stage-specific information, learning activities and social support. It comprises 20 modules, in 19 accessible, facilitated groups for women at a community centre and one home visit. Evidence-informed content is from interventions to address each risk tested in randomised controlled trials in other resource-constrained settings. Content has been translated and culturally adapted for Vietnam and acceptability and feasibility established in pilot testing. We will conduct a two-arm parallel-group cluster-randomised controlled trial, with the commune as clustering unit. An independent statistician will select 84/112 communes in Ha Nam Province and randomly assign 42 to the control arm providing usual care and 42 to the intervention arm. In total, 1008 pregnant women (12 per commune) from 84 clusters are needed to detect a difference in the primary outcome (Bayley Scales of Infant and Toddler Development Cognitive Score \u3c1āSD below standardised norm for 2 years of age) of 15% in the control and 8% in the intervention arms, with 80% power, significance 0.05 and intracluster correlation coefficient 0.03. Ethics and dissemination: Monash University Human Research Ethics Committee (Certificate Number 20160683), Melbourne, Victoria, Australia and the Institutional Review Board of the Hanoi School of Public Health (Certificate Number 017-377IDD- YTCC), Hanoi, Vietnam have approved the trial. Results will be disseminated through a comprehensive multistranded dissemination strategy including peer-reviewed publications, national and international conference presentations, seminars and technical and lay language reports
Toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in the developing male Wistar(Han) rat II: chronic dosing causes developmental delay
We have investigated whether fetal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) causes defects in the male reproductive system of the rat, using chronically exposed rats to ensure continuous exposure of the fetus. 5-6 week old rats were exposed to control diet, or diet containing TCDD, to attain an average dose of 2.4, 8 and 46 ng TCDD kg-1 day-1 for twelve weeks, whereupon the rats were mated, and allowed to litter; rats were switched to control diet after parturition. Male offspring were allowed to develop until kills on PND70 (25 per group), or PND120 (all remaining animals). Offspring from the high dose group showed an increase in total litter loss, and the number of animals alive on post-natal day (PND) 4 in the high dose group was ~26% less than control. The high and medium dose offspring showed decreased weights at various ages. Balano-preputial separation was significantly delayed in all three dose groups, compared to control. There were no significant effects of maternal treatment when the offspring were subjected to a functional observational battery, or learning tests, with the exception that the high dose group showed a deficit in motor activity. 20 rats per group were mated to females, and there were no significant effects of maternal treatment on the fertility of these rats, nor on the F1 or F2 sex ratio. Sperm parameters at PND70 and 120 showed no significant effect of maternal treatment, with the exception that there was an increase in the proportion of abnormal sperm in the high dose group at PND70; this is associated with the developmental delay in puberty in this dose group. There were no remarkable findings of maternal treatment on organ weights, with the exception that testis weights were reduced by ~10% at PND70 (but not PND120), and although the experiment was sufficiently powered to detect small changes, ventral prostate weight was not reduced. There were no significant effects of maternal treatment upon histopathological comparison of high dose and control group organs. These data confirm that developmental exposure to TCDD shows no potent effect on adult sperm parameters or accessory sexual organs, but show that delay in BPS occurs after exposure to low doses of TCDD, and this is dependent upon whether TCDD is administered acutely or chronically
Multiple column high-throughput e-beam inspection (EBI)
Single-column e-beam systems are used in production for the detection of electrical defects, but are too slow to be used for the detection of small physical defects, and can't meet future inspection requirements. This paper presents a multiple-column e-beam technology for high throughput wafer inspection.
Multibeam has developed all-electrostatic columns for high-resolution imaging. The elimination of magnetic coils enables the columns to be small; e-beam deflection is faster in the absence of magnetic hysteresis. Multiple miniature-columns are assembled in an array. An array of 100 columns covers the entire surface of a 300mm wafer, affording
simultaneous cross-wafer sampling. Column performance simulations and system architecture are presented. Also provided are examples of high throughput, more efficient, multiple-column wafer inspection
Fluorescence quenching studies of structure and dynamics in calmodulin-eNOS complexes
This is the peer reviewed version of the following article: Arnett David C.,Persechini Anthony,Tran Quang-Kim,Black D.J. and Johnson Carey K.(2015), Fluorescence quenching studies of structure and dynamics in calmodulināeNOS complexes, FEBS Letters, 589, doi: 10.1016/j.febslet.2015.03.035, which has been published in final form at http://doi.org/10.1016/j.febslet.2015.03.035. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.Activation of endothelial nitric oxide synthase (eNOS) by calmodulin (CaM) facilitates formation of a sequence of conformational states that is not well understood. Fluorescence decays of fluorescently labeled CaM bound to eNOS reveal four distinct conformational states and single-molecule fluorescence trajectories show multiple fluorescence states with transitions between states occurring on time scales of milliseconds to seconds. A model is proposed relating fluorescence quenching states to enzyme conformations. Specifically, we propose that the most highly quenched state corresponds to CaM docked to an oxygenase domain of the enzyme. In single-molecule trajectories, this state occurs with time lags consistent with the oxygenase activity of the enzyme
Fluorescence quenching studies of structure and dynamics in calmodulin-eNOS complexes
This is the peer reviewed version of the following article: Arnett David C.,Persechini Anthony,Tran Quang-Kim,Black D.J. and Johnson Carey K.(2015), Fluorescence quenching studies of structure and dynamics in calmodulināeNOS complexes, FEBS Letters, 589, doi: 10.1016/j.febslet.2015.03.035, which has been published in final form at http://doi.org/10.1016/j.febslet.2015.03.035. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.Activation of endothelial nitric oxide synthase (eNOS) by calmodulin (CaM) facilitates formation of a sequence of conformational states that is not well understood. Fluorescence decays of fluorescently labeled CaM bound to eNOS reveal four distinct conformational states and single-molecule fluorescence trajectories show multiple fluorescence states with transitions between states occurring on time scales of milliseconds to seconds. A model is proposed relating fluorescence quenching states to enzyme conformations. Specifically, we propose that the most highly quenched state corresponds to CaM docked to an oxygenase domain of the enzyme. In single-molecule trajectories, this state occurs with time lags consistent with the oxygenase activity of the enzyme
Mechanical and durability properties of recycled aggregate concrete with ternary binder system and optimized mix proportion
This study aimed to investigate the mechanical and durability properties of recycled aggregate concrete with a ternary binder system and optimized mix proportion. Two concrete batches were developed using a densified mix design approach (DMDA) to evaluate the required mix proportions. Batch I have GGBS content varied at 0%, 10%, 20%, 30%, 40% and 50% at constant w/b ratio of 0.45, while batch II concrete mix have varied water/binder ratios: 0.3, 0.35, 0.4, 0.45 and 0.5 at constant GGBS replacement level of 30%. The fine aggregate (river sand) of the two batches was blended with fly ash at optimum loose packing density (FA + Sand) and superplasticizer (SP) was incorporated in the mix at a constant level of 1.4%. A control mix comprising of natural aggregate was also developed. The results obtained showcased the feasibility of producing structural concrete with recycled aggregates using GGBS and fly ash. The mechanical and durability properties were best at 30% GGBS content and 0.35 water/binder ratio. The DMDA for mix proportion adopted for RAC contributed significantly to improving its properties when compared to NAC, especially at the optimum observed RAC mix with compressive strength of 52 MPa. Also, the mix demonstrated good permeability resistance in terms of chloride-ion ingress and capillary water absorption
mwr Xer site-specific recombination is hypersensitive to DNA supercoiling
The multiresistance plasmid pJHCMW1, first identified in a Klebsiella pneumoniae strain isolated from a neonate with meningitis, includes a Xer recombination site, mwr, with unique characteristics. Efficiency of resolution of mwr-containing plasmid dimers is strongly dependent on the osmotic pressure of the growth medium. An increase in supercoiling density of plasmid DNA was observed as the osmotic pressure of the growth culture decreased. Reporter plasmids containing directly repeated mwr, or the related cer sites were used to test if DNA topological changes were correlated with significant changes in efficiency of Xer recombination. Quantification of Holliday junctions showed that while recombination at cer was efficient at all levels of negative supercoiling, recombination at mwr became markedly less efficient as the level of supercoiling was reduced. These results support a model in which modifications at the level of supercoiling density caused by changes in the osmotic pressure of the culture medium affects resolution of mwr-containing plasmid dimers, a property that separates mwr from other Xer recombination target sites
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