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Applied mathematics(A Journal of Chinese Universities) 2018年第2期33卷 163-176页

作者： hector J.Gomez Neveka m.Olmos hector Varela Heleno Bolfarine Departamento de Ciencias matematicas y Ffsicas Facultad de IngenierlaUniversidad Catolica de TemucoTemucoChile Departamento de matematicas Facultad de Ciencias BasicasUniversidad de AntofagastaAntofagastaChile Departamento de Estatfstica IMEUniversidade de Sao PauloSao PauloBrazil

The main object of this paper is to study an extension of the half normal distribution defined by adding a positive truncation to it. The new model is more flexible than the half-normal distribution and contains the half normal distribution as a special case. Properties of this distribution, such as moments, hazard function and entropy are studied and parameters estimation is dealt with by using inoinents and inaxiinuin likelihood. A real data application indicates good fit performance of the new model when compared to other competitors in litera- tures.

关键词： half-normal distribution maximum likelihood truncation

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先天性长QT综合征的新进展

中国心脏起搏与心电生理杂志 2011年第5期25卷 377-381页

作者：胡丹阮磊张存泰白融 hector m.barajas.martinez Charles Antzelevitch masonic medical Research Laboratory Uticanyusa13501 华中科技大学同济医学院附属同济医院心内科(老年科) 湖北武汉430030

先天性长QT综合征(LQTS)是发病率在1/2 500左右的恶性遗传性心脏疾病。LQTS的典型心脏表现包括可导致心脏骤停和心脏猝死的晕厥发作,以及包括QT间期延长和T波异常在内的心电图异常。90年代中期,LQTS的治病基因被首次发现,至今已有13型... 详细信息

先天性长QT综合征(LQTS)是发病率在1/2 500左右的恶性遗传性心脏疾病。LQTS的典型心脏表现包括可导致心脏骤停和心脏猝死的晕厥发作,以及包括QT间期延长和T波异常在内的心电图异常。90年代中期,LQTS的治病基因被首次发现,至今已有13型被确认。致病基因主要是离子通道和转运相关蛋白。对于具有典型特征的患者,医生并无诊断困难。对于模棱两可的病例,需要参照特殊诊断标准,比如心电图,病史和家族史等等。此外,基因扫描正日益成为诊断过程的一部分。除非有明确的禁忌证,治疗上还是要首选β受体阻滞剂。若在接受足量β受体阻滞剂期间,还有1次以上的晕厥,需立即采取左侧交感神经切除术,并根据病人特征(年龄、性别、临床病史、24 h Holter在内的心电图特征、基因表型等)考虑安装埋藏式心脏转复除颤器。病人接受适当治疗后,一般预后较好。但是LQTS8(Timothy综合征)病人,携带KCNQ1突变的Jervel Lange-Nielsen综合征患者,以及伴有2∶1房室传导阻滞,病窦综合征或Brugada综合征的LQT3病患的预后极其不容乐观。

关键词：心脏猝死长QT综合征综述基因表型危险分层治疗

Atrial-selective Inhibition of Sodium Channel Current by Wenxin Keli is Effective in Suppressing Atrial Fibrillation

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Atrial-selective Inhibition of Sodium Channel Current by Wen...

Geodesic Vulnerability Approach for Identification of Critical Buses in Power Systems

2014中国医师协会中西医结合医师大会

作者： Alexander Burashnikov Alyssa Petroski Dan Hu hector barajas-martinez Charles Antzelevitch masonic medical Research Laboratory

Background—Wenxin Keli is a Chinese herb extract reported to be of benefit in the treatment of cardiac arrhythmias,cardiac inflammation and heart *** and Results—We evaluated the electrophysiologic effects of Wenxin Keli in isolated canine arterially-perfused right atrial preparations with a rim of right ventricular tissue(n = ll).Transmembrane action potentials and a pseudo-electrocardiogram were simultaneously ***(ACh,1 μm) was used to induce atrial fibrillation(AF) and to test the anti-AF potential of Wenxin Keli(5 g/L).Wenxin Keli produced preferential abbreviation of action potential duration(APD90) in atria,but caused atrial-selective prolongation of effective refractory period,due to development of post-repolarization *** maximum rate of rise of the action potential upstroke(Vmax)was preferentially reduced in *** threshold of excitation increased in both atria and ventricles,but much more in *** duration of the "P wave"(index of atrial conduction time)was prolonged to a much greater extent than the duration of the "QRS complex"(index of ventricular conduction time).Wenxin Keli significantly reduced INa and shifted steady-state inactivation to more negative potentials in HEK293 cells stably expressing SCN5 *** Keli prevented induction of persistent AF in 100%atria(6/6)and,in another experimental series was found to terminate persistent ACh-mediated AF in 100%of atria(3/3).Conclusions—Wenxin Keli produces atrial-selective depression of INa-dependent parameters in canine isolated coronary perfused preparations via a unique mechanism and is effective in suppressing AF and preventing its induction,with minimal effects on ventricular electrophysiology.

关键词： Antiarrhythmic drugs atrial fibrillation arrhythmias electrophysiology pharmacology

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Journal of modern Power Systems and Clean Energy 2021年第1期9卷 37-45页

作者： Jesus Beyza Eduardo Garcia-Paricio hector F.Ruiz Jose m.Yusta Instituto Tecnologico de morelia Avenida Tecnologico 1500Lomas de Santiaguito58120Mexico the Department of Electrical Engineering University of ZaragozaC/Maria de Luna 350018Spain

One of the most critical issues in the evaluation of power systems is the identification of critical buses. For this purpose, this paper proposes a new methodology that evaluates the substitution of the power flow technique by the geodesic vulnerability index to identify critical nodes in power *** methods are applied comparatively to demonstrate the scope of the proposed approach. The applicability of the methodology is illustrated using the IEEE 118-bus test system as a case study. To identify the critical components, a node is initially disconnected, and the performance of the resulting topology is evaluated in the face of simulations for multiple cascading faults. Cascading events are simulated by randomly removing assets on a system that continually changes its structure with the elimination of each component. Thus, the classification of the critical nodes is determined by evaluating the resulting performance of 118 different topologies and calculating the damaged area for each of the disintegration curves of cascading failures. In summary, the feasibility and suitability of complex network theory are justified to identify critical nodes in power systems.

关键词： Power system critical node complex network theory cascading failure load flow

Species diversity of thrips (Thysanoptera) in selected avocado orchards from mexico based on morphology and molecular data

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Journal of Integrative Agriculture 2018年第11期17卷 2509-2517页

作者： Daniel Bravo-Perez ma. Teresa Santillbn-Galicia Roberto m. Johansen-Naime hector Gonzalez-Hernandez Obdulia L. Segura-Leon Daniel L, Ochoa-martinez Stephanie Guzman-Valencia Posgrado en Fitosanidad-Entomologia y Acarologia Colegio de Postgraduados Km 36.5 Carretera Mexico-Texcoco Montecillo Texcoco Estado de Mexico 56230 Mexico Instituto de Biologia de la Universidad Nacional Autonoma de mexico (IBUNAm) Circuito exterior s/n Ciudad Universitaria Coyoacan Ciudad de Mexico 04510 Mexico Posgrado en Fitosanidad-Fitopatologia Colegio de Postgraduados Km 36.5 Carretera Mexico-Texcoco Montecillo Texcoco Estado de Mexico 56230 Mexico

Avocado is one of the most important crops in the world, and mexico is the largest producer of this fruit. Several insect pests affect its production, and thrips are amongst the most important. A key step in the design of control methods is accurate species identification. Despite this, formal reports on species diversity of thrips in mexico are very scarce. morphological identification can sometimes be time-consuming and inconclusive. Therefore, we explored the species diversity of thrips in mexican avocado orchards （michoacan state） based on partial sequences of the mitochondrial gene cytochrome oxidase subunit I （COl）. Forty-four specimens were analysed, which represented approximately 8% of all individuals collected from five localities distributed in three municipalities. All specimens were analysed using the COl marker, and specimens within the genera Frankliniella were also analysed using a marker within the D2 domain of the 28S （28SD2） nuclear ribosomal DNA. molecular identifications were confirmed using morphological taxonomy. Overall, six genera were found （Neohydatothrips, Scirtothrips, Frankliniella, Arorathrips, Caliothrips and Leptothrips）. AII genera contained only one species, except Frankliniella, for which there were six species. Data from the two molecular markers suggest the existence of cryptic species within mexican F. occidentalis populations.

关键词： molecular taxonomy morphological identification cytochrome oxidase subunit I 28S nuclear ribosomal DNA.

The implementation and data analysis of an interferometer for intense short pulse laser experiments

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High Power Laser Science and Engineering 2016年第3期4卷 60-66页

作者： Jaebum Park hector A.Baldis Hui Chen Lawrence Livermore National Laboratory University of California

We present an interferometry setup and the detailed fringe analysis method for intense short pulse(SP) laser *** interferometry scheme was refined through multiple campaigns to investigate the effects of pre-plasmas on energetic electrons at the Jupiter Laser Facility at Lawrence Livermore National Laboratory. The interferometer used a frequency doubled(λ=0.527 μm) 0.5 ps long optical probe beam to measure the pre-plasma density, an invaluable parameter to better understand how varying pre-plasma conditions affect the characteristics of the energetic electrons. The hardware of the diagnostic, data analysis and example data are presented. The diagnostic setup and the analysis procedure can be employed for any other SP laser experiments and interferograms, respectively.

关键词： mach-Zehnder interferometer optical interferometry picosecond probe plasma density short pulse laser

A Robust, Fully Adaptive Hybrid Level-Set/Front-Tracking method for Two-Phase Flows with an Accurate Surface Tension Computation

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Communications in Computational Physics 2010年第6期8卷 51-94页

作者： hector D.Ceniceros Alexandre m.Roma Aristeu Silveira-Neto millena m.Villar Department of mathematics University of California Santa BarbaraCA 93106USA Departamento de matematica Aplicada Universidade de Sao PauloCaixa Postal 66281CEP 05311-970Sao Paulo-SPBrasil Faculdade de Engenharia mecanica Universidade Federal de UberlandiaCEP 38400-902Uberlandia-MGBrasil

We present a variable time step,fully adaptive in space,hybrid method for the accurate simulation of incompressible two-phase flows in the presence of surface tension in two *** method is based on the hybrid level set/front-tracking approach proposed in[*** and ***,***.,205,391-400,2005].Geometric,interfacial quantities are computed from front-tracking via the immersed-boundary setting while the signed distance(level set)function,which is evaluated fast and to machine precision,is used as a fluid *** surface tension force is obtained by employing the mixed Eulerian/Lagrangian representation introduced in[***,***-Khalik,*** and ***,***.,203,493-516,2005]whose success for greatly reducing parasitic currents has been *** use of our accurate fluid indicator together with effective Lagrangian marker control enhance this parasitic current reduction by several orders of *** resolve accurately and efficiently sharp gradients and salient flow features we employ dynamic,adaptive mesh *** spatial adaption is used in concert with a dynamic control of the distribution of the Lagrangian nodes along the fluid interface and a variable time step,linearly implicit time integration *** present numerical examples designed to test the capabilities and performance of the proposed approach as well as three applications:the long-time evolution of a fluid interface undergoing Rayleigh-Taylor instability,an example of bubble ascending dynamics,and a drop impacting on a free interface whose dynamics we compare with both existing numerical and experimental data.

关键词： Front-tracking immersed boundary method level set method adaptive mesh re-finements semi-implicit methods multilevel multigrid closest point transform semi-backward difference formula

Effectiveness of a home-environmental intervention package and an early child development intervention on child health and development in high-altitude rural communities in the Peruvian Andes: a cluster-randomised controlled trial

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Infectious Diseases of Poverty 2022年第3期11卷 95-96页

作者： Néstor Nuño Daniel mäusezahl Jan Hattendorf hector Verastegui mariela Ortiz Stella m.Hartinger Department of Public Health and Epidemiology Swiss Tropical and Public Health InstituteKreuzstrasse 2CH-4123AllschwilSwitzerland 不详

Background: Unsafe drinking water,poor sanitation and hygiene,exposure to household air pollution and low cognitive and socio-emotional stimulation are risk factors affecting children in low-and middle-income *** implemented an integrated home-environmental intervention package(IHIP),comprising a kitchen sink,hygiene education and a certified improved biomass cookstove,and an early child development(ECD)programme to improve children´s health and developmental outcomes in the rural high-altitude Andes of ***: We conducted a one-year cluster-randomised controlled trial among 317 childrenmonths divided into 4 arms(IHIP+ECD,IHIP,ECD,and Control)and 40 clusters(10 clusters per arm).ECD status(socio-emotional,fine and gross motor,communication,cognitive skills,and an overall performance)measured with the Peruvian Infant Development Scale and the occurrence of self-reported child diarrhoea from caretakers were primary *** outcomes included the occurrence of acute respiratory infections and the presence of thermo-tolerant faecal bacteria in drinking *** trial was powered to compare each intervention against its control arm but it did not allow pairwise comparisons among the four *** analysis followed the intention-to-treat *** the statistical analysis,we employed generalised estimating equation models with robust standard errors and an independent correlation ***: We obtained ECD information from 101 children who received the ECD intervention(individually and combined with IHIP)and 102 *** who received the ECD intervention performed better in all the domains compared to *** found differences in the overall performance(64 vs.39%,odd ratio(OR):2.8;95%confidence interval(CI):1.6–4.9)and the cognitive domain(62 vs 46%,OR:1.9;95%CI:1.1–3.5).Data analysis of child morbidity included 154 children who received the IHIP intervention(individually and combined with ECD)and 156 ***

关键词： Child development Clinical trial Diarrhoea Improved biomass cookstoves Peru WASH

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先天性长QT综合征的新进展

先天性长QT综合征的新进展