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Competition between Liquid-liquid De-mixing, Crystallization, and Glass Transition in Solutions of PLA of Different Stereochemistry and DEET

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Chinese Journal of Polymer Science 2020年第2期38卷 174-178,I0007页

作者： Chanita Sungkapreecha walter WFocke Rene Androsch Interdisciplinary Center for Transfer-oriented Research in Natural Sciences Martin Luther University Halle-Wittenberg06099 Halle/SaaleGermany University of Pretoria Institute for Sustainable Malaria Control and MRC Collaborating Centre for Malaria Research Department of Chemical EngineeringUniversity of PretoriaPrivate Bag X20Hatfield 0028South Africa

Liquid-liquid(L-L)de-mixing and vitrification of solutions of either crystallizable poly(L-lactic acid)(PLLA)or non-crystallizable poly(D/L-lactic acid)(PDLLA)with 50 m%N,N-diethyl-3-methylbenzamide(DEET)were analyzed by calorimetry and cloud-point measurements,which allows drawing conclusions about the effect of polymer stereochemistry on the phase *** of the PLA stereochemistry,vitrification of the solutions on fast cooling,hindering crystallization of PLLA,occurred below-20℃ and suppressed prior L-L *** experimental results prove that crystallization in samples containing crystallizable PLLA,observed at around 55℃ on slow cooling,is not preceded by L-L de-mixing.

关键词： Crystallization PLA DEET Liquid-liquid phase separation Thermally-induced phase separation(TIPS)

Evaluating the Impact of the Universal Test and Treat Strategy on the Survival of Patients in the Northwest Region of Cameroon

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World Journal of AIDS 2024年第3期14卷 45-60页

作者： Emmanuel Mboh Nshom Bereynuy Jude Cholong Kum Kang walter Khan Eveline Mboh Keng Vitalis Noela F. Ijang Gwendoline Nkenu Nsom Mirabel Mbueh Vifeme Esther Bonje Kuni Monju Johnson Vishi Gladys Enih Fosah Pius Muffih Tih AIDS Care and Prevention Program Cameroon Baptist Convention Health Services Bamenda Cameroon Regional Technical Group for the Fight against HIV and AID Northwest Region Cameroon

Introduction: The main outcome of efficiently implemented universal test and treat (UTT) program is improved survival. UTT implementation has been ongoing in Cameroon since 2016 but evaluation data are scarce. This study aims to assess the survival of antiretroviral therapy (ART) patients initiated under UTT in Northwest region of Cameroon. Methods: This retrospective cohort study included HIV-positive patients initiated in 2016 at 27 purposefully selected sites and followed until 2021. Data was anonymously abstracted from ART registers and patients’ charts. Kaplan-Meier survival estimates and Cox model were used to compare the survival of patients initiated under UTT with those initiated otherwise, using stata version 14.0. Results: In total, 2490 HIV-positive patients (median age 42.7 years, 94.7% adults, and 69.0% female) participated in the study. Of 1389 patients with viral load (VL) test results, 55% were initiated on ART late. The VL suppression rate of patients initiated late and those initiated early were similar. During follow-up, 1020 (40.9%) participants censored. The survival curves of patients initiated early on ART and those initiated late were similar during the first 2.5 years of follow-up but significantly (p Conclusions: This study confirms the expected impact of UTT. Programs only need to close existing implementation gaps along the critical pathways (diagnosis and treatment) of UTT, focusing more on males.

关键词： Universal Test and Treat Viral Load Survival Northwest Cameroon

The Rewards of Fundamental Atomic Spectrometry Research

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光谱学与光谱分析 2000年第2期20卷 156-159页

作者： walter Slavin Bonaire Technologies Ridgefield,CT 06877 USA Bonaire Technologies Ridgefield CT 06877 United States

Atomic spectrometry research is the life blood of the atomic spectrometry instrument *** instrument designer can be expected to innovate in the execution of instrumentation and should be expected to be the expert in optical,electronic and software *** new technology has required too long a period of gestation to be compatible with commercial time scales and *** in the past decade,the pressure from stockholders for increased return on investments has put increasingly strong pressure on management to reduce expenses and focus increasingly on projects that guarantee a fast *** pressure falls particularly heavily on the larger companies;the same companies that a decade or more ago were the ones that brought the more far reaching and expensive new concepts to market. Fundamental research in atomic spectrometry has been accomplished in the past several decades mostly in the academic environment and in research institutions that are Federally *** of the Federally funded research institutions have been forced to alter their missions to more tangible and immediate goals,and many have also seen severe financial reductions.

关键词： The Rewards of Fundamental Atomic Spectrometry Research

High Order Accurate Direct Arbitrary-Lagrangian-Eulerian ADER-MOOD Finite Volume Schemes for Non-Conservative Hyperbolic Systems with Stiff Source Terms

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Communications in Computational Physics 2017年第1期21卷 271-312页

作者： walter Boscheri Raphael Loubere Laboratory of AppliedMathematics Department of CivilEnvironmental and Mechanical EngineeringUniversity of TrentoI-38123 TrentoItaly CNRS and Institut de Mathematiques de Toulouse(IMT)Universite Paul-Sabatier ToulouseFrance

In this paper we present a 2D/3D high order accurate finite volume scheme in the context of direct Arbitrary-Lagrangian-Eulerian algorithms for general hyperbolic systems of partial differential equations with non-conservative products and stiff source *** scheme is constructed with a single stencil polynomial reconstruction operator,a one-step space-time ADER integration which is suitably designed for dealing even with stiff sources,a nodal solver with relaxation to determine the mesh motion,a path-conservative integration technique for the treatment of non-conservative products and an a posteriori stabilization procedure derived from the so-called Multidimensional Optimal Order Detection(MOOD)*** this work we consider the seven equation Baer-Nunziato model of compressible multi-phase flows as a representative model involving non-conservative products as well as relaxation source terms which are allowed to become *** new scheme is validated against a set of test cases on 2D/3D unstructured moving meshes on parallel machines and the high order of accuracy achieved by the method is demonstrated by performing a numerical convergence *** Riemann problems and explosion problems with exact solutions are simulated in 2D and *** overall numerical code is also profiled to provide an estimate of the computational cost required by each component of the whole algorithm.

关键词： Direct Arbitrary-Lagrangian-Eulerian a posteriori MOOD stabilization Baer-Nunziato model stiff source terms non-conservative products unstructured mesh ADER high order of accuracy in space and time high performance computing(HPC) hyperbolic conservation laws

A Resilient Control Strategy for Cyber-Physical Systems Subject to Denial of Service Attacks:A Leader-Follower Set-Theoretic Approach

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IEEE/CAA Journal of Automatica Sinica 2020年第5期7卷 1204-1214页

作者： Giuseppe Franzè Domenico Famularo walter Lucia Francesco Tedesco DIMES Department Universitàdella CalabriaVia Pietro Bucci 87036Italy CIISE Department Concordia UniversityMontrealQuebec H3G-1M8Canada IEEE

Multi-agent systems are usually equipped with open communication infrastructures to improve interactions efficiency,reliability and *** technologically costeffective,this makes them vulnerable to cyber-attacks with potentially catastrophic *** this end,we present a novel control architecture capable to deal with the distributed constrained regulation problem in the presence of time-delay attacks on the agents’communication *** basic idea consists of orchestrating the interconnected cyber-physical system as a leader-follower configuration so that adequate control actions are computed to isolate the attacked unit before it compromises the system *** on a multi-area power system confirm that the proposed control scheme can reconfigure the leader-follower structure in response to denial ofservice(DoS)attacks.

关键词： Denial-of-service(DoS)attacks distributed model predictive control leader-follower paradigm resilient control

Potential of Zimbabwean commercial probiotic products and strains of Lactobacillus plantarum as prophylaxis and therapy against diarrhoea caused by Escherichia coli in children

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Asian Pacific Journal of Tropical Medicine 2017年第1期10卷 57-62页

作者： walter Chingwaru Jerneja Vidmar Department of Biological Sciences Faculty of ScienceBindura University Science EducationP.Bag 1020BinduraZimbabwe Maribor Institute of Biomedical Sciences Žitna ulica 102000 MariborSlovenia Institute Ceres/Zavod Ceres Lahovna 163000 CeljeSlovenia Department of Plastic and Reconstructive Surgery University Medical Centre MariborLjubljanska 52000 MariborSlovenia

Objective: To evaluate the potential of commercial fermented products sold in the country,and strains of Lactobacillus plantarum(L,plantarum)as prophylaxis and therapy against diarrhoea in children,Methods: The antimicrobial potential of cultures of lactobacilli enriched from 4 Zimbabwean commercial food/beverage products: Dairibord Lacto sour milk(DLSM),Probrand sour milk(PSM),Kefalos Vuka cheese(KVC) and Chibuku opaque beer(COB); and four strains of L,plantarum obtained from Balkan traditional cheeses against clinical strains of Escherichia coli(E,coli) was assayed using the well diffusion method,Three commercial paediatric antidiarrhoeal drug products: Biogaia(BG),Prolife(PL) and Probio Junior(PJ) and a mutant strain of E,coli [strain 11105(ATCC)- a vitamin B-12 auxotroph and penicillin G acylase-producing strain] were used as controls,An agar diffusion assay and a competitive exclusion assay were carried out on Mueller Hinton agar,Results: Crude cultures of putative lactobacillus strains obtained from Zimbabwean dairy products(Probrand sour milk,Kefalos Vuka vuka cheese and Chibuku opaque beer) had significantly higher antimicrobial activities against clinical strains of E,coli than strains of L,plantarum isolated from Balkan cheeses(CLP1,CLP2 or CLP3) and crude microbial cultures from commercial paediatric probiotic products(BG,PJ and PL) of a culture of Lactobacillus rhamnosus LGG(P<0.05),Conclusions: The putative Lactobacilli from four commercial Zimbabwean dairy products(Probrand sour milk,Kefalos Vuka vuka cheese and Chibuku opaque beer),and three strains of L,plantarum from Balkan cheeses(CLP1,CLP2 or CLP3) exhibited high antibacterial activities that can be harnessed to control paediatric diarrhoea that is caused by pathogenic strains of E,coli,Studies to characterise the probiotic potential of the live cultures in the products and the new strains of L,plantarum are underway.

关键词： Probiotic Inhibition Escherichia coli Lactobacillus plantarum Diarrhoea Paediatric

A chaotic neural network mimicking an olfactory system and its application on image recognition

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Journal of Bionic Engineering 2004年第3期1卷 191-198页

作者： walter J. Freeman Department of Molecular & Cell Biology UCB LSA 142 Berkeley CA 94720-3200 USA

Based on the research of a biological olfactory system, a novel chaotic neural network model - K set model has been es- tablished. This chaotic neural network not only simulates the real brain activity of an olfactory system, but also presents a novel chaotic concept for signal processing and pattern recognition. The characteristics of the K set models are investigated and show that a KIII model can be used for image pattern classification.

关键词： olfactory system pattern recognition neural networks image classification

Terahertz Spectroscopic Characterization and Thickness Evaluation of Internal Delamination Defects in GFRP Composites

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Chinese Journal of Mechanical Engineering 2023年第1期36卷 190-210页

作者： walter Nsengiyumva Shuncong Zhong Manting Luo Bing Wang Fujian Provincial Key Laboratory of Terahertz Functional Devices and Intelligent Sensing School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou350108China Institute of Precision Instrument and Intelligent Measurement&Control Fuzhou UniversityFuzhou350108P.R.China School of Mechanical and Electrical Engineering Putian UniversityPutian351100China

The use of terahertz time-domain spectroscopy(THz-TDS)for the nondestructive testing and evaluation(NDT&E)of materials and structural systems has attracted significant attention over the past two decades due to its superior spatial resolution and capabilities of detecting and characterizing defects and structural damage in non-conducting *** this study,the THz-TDS system is used to detect,localize and evaluate hidden multi-delamination defects(i.e.,a three-level multi-delamination system)in multilayered GFRP composite *** obtain accurate results,a wavelet shrinkage de-noising algorithm is used to remove the noise from the measured time-of-flight(TOF)*** thickness and location of each delamination defect in the z-direction(i.e.,through-the-thickness direction)are calculated from the de-noised TOF signals considering the interaction between the pulsed THz waves and the different interfaces in the GFRP composite laminates.A comparison between the actual and the measured thickness values of the delamination defects before and after the wavelet shrinkage denoising process indicates that the latter provides better results with less than 3.712%relative error,while the relative error of the non-de-noised signals reaches 16.388%.Also,the power and absorbance levels of the THz waves at every interface with different refractive indices in the GFRP composite laminates are evaluated based on analytical and experimental *** present study provides an adequate theoretical analysis that could help NDT&E specialists to estimate the maximum thickness of GFRP composite materials and/or structures with different interfaces that can be evaluated by the ***,the accuracy of the obtained results highlights the capabilities of the THz-TDS for the NDT&E of multilayered GFRP composite laminates.

关键词： Glass-fiber-reinforced polymer-matrix(GFRP)composites Terahertz time-domain spectroscopy(THz-TDS) Nondestructive testing and evaluation(NDT&E) Stationary wavelet transform(SWT) Thickness evaluation Delamination defects

The mysteries of eccentric muscle action

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运动与健康科学（英文） 2018年第3期7卷 253-254页

作者： walter Herzog Human Performance Laboratory Faculty of KinesiologyUniversity of Calgary

Muscle actions are typically divided into 3 categories：concentric,isometric,and *** active muscle that is shortening and produces positive mechanical work is said to work concentrically;an active muscle that is not changing its length,and thus does not produce net work,is said to work isometrically;and an active muscle that is elongated by external forces,and thus absorbs work,or produces negative work,is said to work eccentrically．

关键词：运动科学健康科学个人休闲运动