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Interpenetrating polymers supported on microporous polypropylene membranes for the transport of chromium ions

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Chinese Journal of Chemical Engineering 2017年第7期25卷 938-946页

作者： Yesid Tapiero Julio sánchez BernabéL.Rivas Polymer department Faculty of ChemistryUniversity of ConcepdonCasilla 160-C ConcepcionChile

Modifying polypropylene membranes with interpenetrating polymer networks(IPNs) through the incorporation of poly(glycidyl methacrylate-N-methyl-D-glucamine)(P(GMA-NMG)) was performed by in situ synthesis via radical polymerization. The surface of the polypropylene membrane was activated by hydrophilic grafted polyelectrolyte, and then, pressure injection was used for the impregnation of the reactive solution in the *** types of pore-filled membranes were synthesized, chelating interpenetrating homopolymer networks of P(GMA-NMG), and chelating-ion exchange interpenetrating polymer networks(e.g., P(GMA-NMG)/P(AA),P(GMA-NMG)/P(AMPsA), and P(GMA-NMG)/P(Cl VBTA)). After their synthesis, the modified polypropylene membranes were characterized using techniques such as the electrokinetic potential, sEM, FT-IR, and Donnan dialysis to corroborate the chromium ion transport. The P(GMA-NMG) and complex network membranes exhibited a hydrophilic character with a water-uptake capacity between 20% and 35% and a percentage of modification between 4.0% and 7.0% in comparison with the behavior of the unmodified polypropylene *** chromium ions were efficiently transported from the food chamber at p H 9.0 when the 65.2%MTA1 P(Cl VBTA) homopolymer IPN membrane and 48.5% MTAG P(GMA-NMG)/P(Cl VBTA) IPN membrane were used. similarly, hexavalent chromium ions were removed from the food chamber at pH 3.0 when MTAG(63.30%) and MTA1(35.68%) were used in 1 mol·L^(-1)Na Cl solution as the extraction reagent.

关键词： Polypropylene N-methyI-D-glucamine Ion exchange Donnan dialysis Interpenetrating polymer networks Chromium

Annealing Effects on the structural, Optical, and UV Photoresponse Properties of ZnO Nanostructures Prepared by RF-Magnetron sputtering at Different Deposition Temperatures

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Acta Metallurgica sinica(English Letters) 2015年第2期28卷 230-242页

作者： Husam s.Al-salman M.J.Abdullah school of Physics University Sains Malaysia department of Physics College of Science University of Basrah

Undoped ZnO nanostructures were deposited on siO2/si substrates via radio 11：equency magnetron sputtenng at different deposition temperatures （room temperature, 200, 300, and 400 ℃）. The prepared samples were annealed at 500 ℃ for 2 h under an N2 flow. The structural, surface morphological, optical, and photoresponse characteristics of ZnO nanostructures as deposited and after annealing were then investigated. The energy bandgaps of all samples after annealing （3.22-3.28 eV） decreased compared with those of the as-deposited specimens. The barrier height increased when the deposition temperature increased and reached 0.77 eV at 400 ℃ after annealing with a leakage current of 0.17 ga at a 5 V bias. The UV photodetector device which was deposited at the optimal temperature of 300 ℃, has 12.51 × 10^3% pho- tosensitivity, 2.259 pA dark current, 0.508 s response time, and 0.466 s recovery time. The dark current significantly decreased for all samples after annealing. The proposed UV photodetectors exhibit high performance, high photosensi- tivity, shorter response and recovery times, and excellent stability at lower bias voltages of 5 and 2 V.

关键词： Undoped ZnO UV photoresponse Deposition temperatures Annealing effect

Optimization of assembly line balancing using genetic algorithm

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Journal of Central south univers.ty 2015年第10期22卷 3957-3969页

作者： N.Barathwaj P.Raja s.Gokulraj school of Mechanical Engineering SASTRA University Rane (Madras) Ltd. Deputy Manager (Manufacturing Engineering System Design Department)

In a manufacturing industry, mixed model assembly line(MMAL) is preferred in order to meet the variety in product demand. MMAL balancing helps in assembling products with similar characteristics in a random fashion. The objective of this work aims in reducing the number of workstations, work load index between stations and within each station. As manual contribution of workers in final assembly line is more, ergonomics is taken as an additional objective function. Ergonomic risk level of a workstation is evaluated using a parameter called accumulated risk posture(ARP), which is calculated using rapid upper limb assessment(RULA) check sheet. This work is based on the case study of an MMAL problem in Rane(Madras) Ltd.(India), in which a problem based genetic algorithm(ga) has been proposed to minimize the mentioned objectives. The working of the genetic operators such as selection, crossover and mutation has been modified with respect to the addressed MMAL problem. The results show that there is a significant impact over productivity and the process time of the final assembled product, i.e., the rate of production is increased by 39.5% and the assembly time for one particular model is reduced to 13 min from existing 18 min. Also, the space required using the proposed assembly line is only 200 m2 against existing 350 m2. Further, the algorithm helps in reducing workers fatigue(i.e., ergonomic friendly).

关键词： optimization line balancing genetic algorithm product family assembly line

A wonderful time - exciting progress made in the past 20 years in genetics powered by the Human Genome Project

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Quantitative biology 2021年第4期9卷 366-370页

作者： Zhaohui s.Qin department of Biostatistics and Bioinformatics Rollins School of Public HealthEmory UniversityAtlantaGA 30322USA

This year marks the 20-year anniversary of the publication of the draft human *** this article,I review the fundamental impact the Human Genome Project(HGP)has made in biomedical research,especially in the genetics field.I also offer some perspective from the viewpoint of a bioinformatics and quantitative genetics researcher,what the future looks like for the next 20 years and beyond.

关键词： Human wonderful anniversary

Obsolescence optimization of electronic and mechatronic components by considering dependability and energy consumption

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Journal of Central south univers.ty 2013年第5期20卷 1221-1225页

作者： M.A.Mellal s.Adjerid D.Benazzouz s.Berrazouane E.J.Williams solid Mechanics and system Laboratory Faculty of Engineering Sciences (FSI)M'Hamed Bougara University Faculty of Engineering sciences (FsI) M'Hamed Bougara University Decision sciences College of BusinessUniversity of Michigan Industrial and Manufacturing systems Engineering department College of Engineering and Computer ScienceUniversity of Michigan

Nowadays, rapid technological progress influences the dependability of equipments and also causes rapid obsolescence. The mechatronic and electronic equipment components are mostly affected by obsolescence. A new challenger unit possesses identical functionalities, but with higher performances. This work aims to find the optimal number of components which should be replaced by new-type units, under budgetary constraints. In this work, the new challenger unit is characterized by lower energy consumption and the optimization steps are based on genetic algorithm (ga). The result shows the importance of this type of replacement in order to economize energy consumption and to deal with obsolescence.

关键词： obsolescence lower energy consumption mechatronic and electronic components genetic algorithm

Epidemiological and Clinical Profile and Immediate Outcome of Neonates Transferred from the Maternity Unit to the Neonatology Unit of the CsREF in Commune V of Bamako District, Mali

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Open Journal of Pediatrics 2024年第3期14卷 547-557页

作者： Maimouna Kante Ya Traoré Balilé Harber Beydari Mamadou Traoré Issiaka Koné Diéneba sacko Maimouna Haidara Korotoumou Bamba Assitan Farota Abdoulaye Kassogué Mohamed Diarra Dramane Touré Abdoul salam Diarra Leyla Maïga Dicko Fatoumata Paediatric Ward CSR&#233f CV Bamako Mali Paediatric Ward of Nianankoro Fomba Hospital S&#233gou Mali Paediatric Ward of Kalaban CoroCsREF Bamako Mali Pediatric department of the Mopti Reference Health Center Mopti Mali National Centre for scientific and Technological Research Bamako Mali Paediatrics department Mohamed VI Perinatal Clinic Bamako Mali department of Paediatrics Gabriel Tour&#233 University Hospital Bamako Mali

Introduction: Neonatal mortality remains a major public health concern. According to the World Health Organisation (WHO), the number of newborns dying each year has fallen from 5 million in 1990 to 2.4 million in 2019. The aim of our study was to describe the main morbid conditions and their lethality in newborns admitted to the paediatric ward of the CsREF in Commune V. Methodology: We conducted a 12-month prospective descriptive and analytical study from August 2020 to July 2021. Results: During the 12 months of the study, out of 2654 neonates admitted to hospital, 216 met our inclusion criteria, i.e. 8%. Newborns admitted in the first few hours of life represented 99.54% of cases. Full-term newborns accounted for 65.74% of the total. Forty-eight percent of newborns had hypothermia on admission. The most common diagnosis was asphyxia in 55.56% of cases, followed by neonatal infection in 27.78% and prematurity in 10.65%. Death was recorded in 22.2% of cases. Asphyxia was the main cause of neonatal death, followed by prematurity in our context. Conclusion: Improving the prognosis of newborn babies will require a thorough understanding of neonatal pathologies and the implementation of a pre- and perinatal prevention policy.

关键词： Newborns Morbidity Mortality

A Novel Radial Basis Function Neural Network Approach for ECG signal Classification

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Intelligent Automation & soft Computing 2023年第1期35卷 129-148页

作者： s.sathishkumar R.Devi Priya department of Information Technology Adhiyamaan College of EngineeringHosur621004India department of Information Technology Kongu Engineering CollegeErode638060India

ions in the ECG *** cardiologist and medical specialistfind numerous difficulties in the process of traditional *** specified restrictions are eliminated in the proposed *** fundamental aim of this work is tofind the R-R *** analyze the blockage,different approaches are implemented,which make the computation as facile with high *** information are recovered from the MIT-BIH *** retrieved data contain normal and pathological ECG *** obtain a noiseless signal,gaborfilter is employed and to compute the amplitude of the signal,DCT-DOsT(Discrete cosine based Discrete orthogonal stock well transform)is *** amplitude is computed to detect the cardiac *** R peak of the underlying ECG signal is noted and the segment length of the ECG cycle is *** Genetic algorithm(ga)retrieves the primary highlights and the classifier integrates the data with the chosen attributes to optimize the *** addition,the ga helps in performing hereditary calculations to reduce the problem of multi-target ***,the RBFNN(Radial basis function neural network)is applied,which diminishes the local minima present in the *** shows enhancement in characterizing the ordinary and anomalous ECG signals.

关键词： Electrocardiogram signal gaborfilter discrete cosine based discrete orthogonal stock well transform genetic algorithm radial basis function neural network

Pluripotent stem Cells Models for Huntington's Disease:Prospects and Challenges

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Journal of Genetics and Genomics 2012年第6期39卷 253-259页

作者： Richard L. Carter Anthony W.s.Chan Yerkes National Primate Research Center 954 Gatewood Rd.N.E.AtlantaGA 39329USA Genetic and Molecular biology Program Graduate Division of Biologieal and Biomedical SciencesEmory UniversityAtlantaGA 30322USA department of Human Genetics Emory University School of Medicine615 Michael St.AtlantaGA 30322USA

Pluripotent cellular models have shown great promise in the study of a number of neurological disorders. several advantages of using a stem cell model include the potential for cells to derive disease relevant neuronal cell types, providing a system for researchers to monitor disease progression during neurogenesis, along with serving as a platform for drug discovery. A number of stem cell derived models have been employed to establish in ~,itro research models of Huntington＇s disease that can be used to investigate cellular pathology and screen lk^r drug and cell-based therapies. Although some progress has been made, there are a number of challenges and limitations that must be overcome before the true potential of this research strategy is achieved. In this article we review current stem cell models that have been reported, as well as discuss the issues that impair these studies. We also highlight the prospective application of Huntington＇s disease stem cell models in the development of novel therapeutic strategies and advancement of personalized medicine.

关键词： stem cell models Huntington's disease Induced pluripotent stem cells Drug discovery

Comparing children＇s Homo sapiens and chimpanzees＇ Pan troglodytes quantity judgments of sequentially presented sets of items

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Current Zoology 2011年第4期57卷 419-420,421-428页

作者： Michael J. BERAN Julie s. JOHNsON-PYNN Christopher READY Language Research Center Georgia State University Atlanta GA 30302 USA department of Psychology Berry College Mount Berry GA 30149 USA

We presented a quantity judgment task that involved comparing two sequentially presented sets of items to preschoolers and chimpanzees using nearly identical procedures that excluded verbal instructions to children. Trial difficulty in this task reflected the ratio difference between sets of discrete items where larger ratios （e.g., 0.80 as from comparing 4 to 5） were more difficult than smaller ones （e.g., 0.50 as from comparing 4 to 8）. Children also completed verbal-based tasks probing the relationskip between counting proficiency and performance on the quantity judgment task of sequentially presented identical sized items. Both species＇ performance was best when ratios between comparison sets were small regardless of set size in all types of tasks. Generally, chimpanzees and older children performed better than younger children except at larger ratios. Children＇s counting proficiency was not related to success in choosing the larger of two quantities of identical-sized items. These results indicate that chimpanzees and children share an approximate number sense that is reflected through analog magnitude estimation when comparing quantities [Current Zoology 57 （4）： 419-428, 2011].

关键词： Numerical cognition Quantity judgments Children Chimpanzees Pan troglodytes