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Synthesis,Urease Inhibition and Molecular Modelling Studies of Novel Derivatives of the Naturally Occurring b-Amyrenone

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Natural Products and Bioprospecting 2019年第1期9卷 49-59页

作者： jean j.k.bankeu Hira Sattar Yannick S.F.Fongang Syeda W.Muhammadi Conrad V.Simoben Fidele Ntie-kang Guy R.T.Feuya Marthe A.T.Tchuenmogne Mehreen Lateef Bruno N.Lenta Muhammad S.Ali Augustin S.Ngouela Department of Chemistry Faculty of ScienceThe University of BamendaP.O.Box 39BambiliCameroon International Center for Chemical and Biological Sciences University of KarachiKarachi 75270Pakistan Department of Chemistry Higher Teacher Training CollegeUniversity of MarouaP.O.Box 55MarouaCameroon Department of Pharmaceutical Chemistry Martin-Luther University of Halle-WittenbergWolfgang-Langenbeck-Str.406120 Halle(Saale)Germany Department of Chemistry Faculty of ScienceUniversity of BueaP.O.Box 63BueaCameroon Department of Chemistry Faculty of ScienceScientific and Technical University of MasukuBox 943FrancevilleGabon Department of Chemistry Faculty of ScienceUniversity of Yaounde´IP.O.Box 812Yaounde´Cameroon Multi-Disciplinary Research Laboratory(MDRL) Bahria University Medical and Dental CollegeBahria UniversityKarachiPakistan Department of Chemistry Higher Teacher Training CollegeUniversity of Yaounde´IP.O.Box 47Yaounde´Cameroon

Urease enzyme(UE)has been reported to be a potent virulence factor for Helicobacter pylori(HP)bacteria indicated to be responsible for various gastrointestinal ***,the spread of HP,currently regarded by the World Health Organization as a class 1 carcinogen,could be better controlled by targeting *** is in this line that we have synthesized three new derivatives(2–4)of the naturally occurring olean-12-en-3-one(1),which was previously isolated from the figs of Ficus vallis-choudae Delile(Moraceae).Among the synthesized compounds,3 and 4 contain an indole *** structures were unambiguously assigned by spectroscopic and spectrometric techniques(1D-NMR,2D-NMR and MS).The starting material and the synthesized compounds were screened for UE inhibition activity,and showed significant activities with IC50 values ranging from 14.5 to 24.6 lM,with compound(1)being the most potent as compared to the positive control thiourea(IC50=21.6 lM).Amongst the synthetic derivatives,compound 4 was the most potent(IC50-=17.9 lM),while the others showed activities close to that of the *** addition,molecular docking study of target compounds 2–4 was performed in an attempt to explore their binding mode for the design of more potent UE inhibitors.

关键词： Helicobacter pylori Urease inhibition Docking Olean-12-en-3-one derivatives

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Multi-Model Approach for Assessing the Influence of Calibration Criteria on the Water Balance in Ouémé Basin

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journal of Water Resource and Protection 2024年第3期16卷 207-218页

作者： Aymar Yaovi Bossa Mahutin Aristide Oluwatobi kpossou jean Hounkpè Félicien Djigbo Badou National Institute of Water University of Abomey-Calavi Cotonou Benin Ecole d’Horticulture et d’Aménagement Des Espaces Verts Université Nationale d’Agriculture Kétou Benin

Hydrological models are very useful tools for evaluating water resources, and the hydroclimatic hazards associated with the water cycle. However, their calibration and validation require the use of performance criteria which choice is not straightforward. This paper aims to evaluate the influence of the performance criteria on water balance components and water extremes using two global rainfall-runoff models (HBV and GR4j) over the Ouémé watershed at the Bonou and Savè outlets. Three (3) Efficacy criteria (Nash, coefficient of determination, and kGE) were considered for calibration and validation. The results show that the Nash criterion provides a good assessment of the simulation of the different parts of the hydrograph. kGE is better for simulating peak flows and water balance elements than other efficiency criteria. This study could serve as a basis for the choice of performance criteria in hydrological modelling.

关键词： Hydrological Modelling Performance Criteria Water Balance Ouémé Basin

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Carbon storage and net primary productivity in Canadian boreal mixedwood stands

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journal of Forestry Research 2019年第5期30卷 1667-1678页

作者： Nicholas j.Payne D.Allan Cameron jean-Denis Leblanc Ian k.Morrison Canadian Forest Service Great Lakes Forestry Centre

Canadian boreal mixedwood forests are extensive,with large potential for carbon sequestration and storage;thus,knowledge of their carbon stocks at different stand ages is needed to adapt forest management practices to help meet climate-change mitigation *** stocks were quantified at three Ontario boreal mixedwood sites.A harvested stand,a juvenile stand replanted with spruce seedlings and a mature stand had total carbon stocks(±SE)of 133±13 at age 2,130±13 at age 25,and 207±15 Mg C ha^-1 at age 81 *** the clear-cut site,stocks were reduced by about 40%or 90 Mg C ha^-1 at *** held 27,34 and 62%of stocks,while detritus held 34,29 and 13%of stocks at age 2,25 and 81,*** soil carbon stocks averaged 51 Mg C ha^-1,and held 38,37 and 25%of *** net primary productivity(±SE)in the harvested and juvenile stand was 2.1±0.2 and 3.7±0.3 Mg C ha^-1 per annum(p.a.),compared to 2.6±2.5 Mg C ha^-1 *** the mature *** mature canopies studied had typical boreal mixedwood composition and mean carbon densities of 208 Mg C ha^-1,which is above average for managed Canadian boreal forest ecosystems.A comparison of published results from Canadian boreal forest ecosystems showed that carbon stocks in mixedwood stands are typically higher than coniferous stands at all ages,which was also true for stocks in vegetation and ***,aboveground net primary productivity was typically found to be higher in mixedwood than in coniferous boreal forest stands over a range of *** from this study,together with those published from the other boreal forest stands demonstrate the potential for enhanced carbon sequestration through modified forest management practices to take advantage of Canadian boreal mixedwood stand characteristics.

关键词： Aboveground net primary productivity Boreal mixedwood forest Carbon stocks Mixedwood stand management Stand age

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A unified electrical model based on experimental data to describe electrical transport in carbon nanotube-based materials

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Nano Research 2020年第6期13卷 1764-1779页

作者： Yoann Dini jérôme Faure-Vincent jean Dijon Univ.Grenoble-Alpes CEALITENDTNMF-38000GrenobleFrance Univ.Grenoble-Alpes CEACNRSIRIGSyMMESF-38000GrenobleFrance

Understanding the electrical transport in carbon nanotube(CNT)materials is one key to reach very high electrical *** CNT material resistivity(ρ(T))as function of the temperature are fully apprehended by their reduced activation W(T)=dln(ρ)/dln(T)*** to now,no model accurately fits W(T)curves,thus preventing from precisely describing the CNT material electrical *** present a new electrical transport model that perfectly fits all W(T)curves found in the literature and in our own *** material resistivities are modeled byρ(T)=ρ0(T^−α+M(1+βTγT^2)).Our model has few enough parameters(α,M,β,γ)to relate them to the CNT *** 70 k,we experimentally show that CNT material resistivity follows the Luttinger Liquid theory justifying the T^−αterm in our *** 70 k,the polynomial part becomes dominant and depends on the two different CNT fabrication techniques which lead to two very different yarn *** yarns made from floating catalyst chemical vapor deposition CNTs,the polynomial is explained by the percolation of metallic CNT ***,the polynomial of yarns spun from CNT arrays is explained by the electrical transport in CNT bundles which are the basic building blocks of this type of yarns.

关键词： carbon nanotube carbon-based materials electrical conductivity electrical transport model Luttinger Liquid

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Type II Fuzzy Logic Based Cluster Head Selection for Wireless Sensor Network

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Computers, Materials & Continua 2022年第1期70卷 801-816页

作者： j.jean justus M.Thirunavukkarasan k.Dhayalini G.Visalaxi Adel khelifi Mohamed Elhoseny Department of Computer Science&Engineering St.Joseph’s College of EngineeringChennai600119India School of Computing Science and Engineering Galgotias UniversityUttar Pradesh203201India Department of Electrical and Electronics Engineering K.Ramakrishnan College of EngineeringTiruchirappalli621112India Department of Computer Science&Engineering Bharath Institute of Higher Education and ResearchChennai600073India Department of Computer Science and Information Technology Abu Dhabi UniversityAbu Dhabi59911United Arab Emirates College of Computer Information Technology American University in the EmiratesDubaiUnited Arab Emirates Faculty of Computers and Information Mansoura UniversityEgypt

Wireless Sensor Network(WSN)forms an essential part of *** is embedded in the target environment to observe the physical parameters based on the type of *** nodes inWSN are constrained by different features such as memory,bandwidth,energy,and its processing *** WSN,data transmission process consumes the maximum amount of energy than sensing and processing of the ***,diverse clustering and data aggregation techniques are designed to achieve excellent energy efficiency in *** this view,the current research article presents a novel Type II Fuzzy Logic-based Cluster Head selection with Low Complexity Data Aggregation(T2FLCH-LCDA)technique for *** presented model involves a two-stage process such as clustering and data ***,three input parameters such as residual energy,distance to Base Station(BS),and node centrality are used in T2FLCH technique for CH selection and cluster ***,the LCDA technique which follows Dictionary Based Encoding(DBE)process is used to perform the data aggregation at ***,the aggregated data is transmitted to the BS where it achieves energy *** experimental validation of the T2FLCH-LCDAtechnique was executed under three different scenarios based on the position of *** experimental results revealed that the T2FLCH-LCDA technique achieved maximum energy efficiency,lifetime,Compression Ratio(CR),and power saving than the compared methods.

关键词： Clustering data aggregation energy consumption cluster head selection wireless sensor networks

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To forage or hide？ Threat-sensitive foraging behaviour in wild, non-reproductive passerine birds

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Current Zoology 2014年第6期60卷 719-728页

作者： Shaun TURNEY jean-Guy j. GODIN Department of Biology Carleton University Ottawa ON K1 S 5B6 Canada Department of Biology McGill University Montreal QC H3A 1B 1 Canada

Because antipredator behaviours are costly, the threat-sensitive predator avoidance hypothesis predicts that individual animals should express predator-avoidance behaviour proportionally to the perceived threat posed by the predator. Here, we experimentally tested this hypothesis by providing wild passerine birds supplemental food （on a raised feeding platform） at either 1 or 4 m from the edge of forest cover （potential refuge）, in either the presence or absence of a nearby simulated predation threat （a sharp-shinned hawk Accipiter striatus model）. Compared with the control treatment, we observed proportionally fewer bird visits to the food patch, and the birds took longer to re-emerge from forest refuge and return to feed at the food patch, after the hawk presentation than before it. The observed threat-sensitive latency-to-return response was stronger when the food patch was further away from the nearest refuge. Overall, our results are consistent with the predictions of the threat-sensitive predator avoidance hypothesis in that wild passerine birds （primarily black-capped chickadees Poecile atricapillus） exhibited more intense antipre- dator behavioural responses with increasing level of apparent threat. The birds were thus sensitive to their local perceived threat of predation and traded-off safety from predation （by refuging） and foraging gains in open habitat in a graded, threat-sensitive manner [Current Zoology 60 （6）： 719-728, 2014].

关键词： Foraging Predation risk Threat sensitivity Risk taking Distance-to-refuge Birds

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Hybridization of Metaheuristics Based Energy Efficient Scheduling Algorithm for Multi-Core Systems

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Computer Systems Science & Engineering 2023年第1期44卷 205-219页

作者： j.jean justus U.Sakthi k.Priyadarshini B.Thiyaneswaran Masoud Alajmi Marwa Obayya Manar Ahmed Hamza Department of Computer Science&Engineering St.Joseph’s College of EngineeringChennai600119India Department of Computer Science and Engineering Saveetha School of EngineeringSIMATSChennai602105India Department of Electronics and Communication Engineering K.Ramakrishnan College of EngineeringTiruchirappalli621112India Department of Electronics and Communication Engineering Sona College of TechnologySalem636005India Department of Computer Engineering College of Computers and Information TechnologyTaif UniversityTaif21944Saudi Arabia Department of Biomedical Engineering College of EngineeringPrincess Nourah bint Abdulrahman UniversityRiyadh11671Saudi Arabia Department of Computer and Self Development Preparatory Year DeanshipPrince Sattam bin Abdulaziz UniversityAlKharjSaudi Arabia

The developments of multi-core systems(MCS)have considerably improved the existing technologies in thefield of computer *** MCS comprises several processors that are heterogeneous for resource capacities,working environments,topologies,and so *** existing multi-core technology unlocks additional research opportunities for energy minimization by the use of effective task *** the same time,the task scheduling process is yet to be explored in the multi-core *** paper presents a new hybrid genetic algorithm(GA)with a krill herd(kH)based energy-efficient scheduling techni-que for multi-core systems(GAkH-SMCS).The goal of the GAkH-SMCS tech-nique is to derive scheduling tasks in such a way to achieve faster completion time and minimum energy *** GAkH-SMCS model involves a multi-objectivefitness function using four parameters such as makespan,processor utilization,speedup,and energy consumption to schedule tasks *** performance of the GAkH-SMCS model has been validated against two datasets namely random dataset and benchmark *** experimental outcome ensured the effectiveness of the GAkH-SMCS model interms of makespan,pro-cessor utilization,speedup,and energy *** overall simulation results depicted that the presented GAkH-SMCS model achieves energy effi-ciency by optimal task scheduling process in MCS.

关键词： Task scheduling energy efficiency multi-core systems fitness function makespan

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Targeted therapy for capillary-venous malformations

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Signal Transduction and Targeted Therapy 2024年第7期9卷 3024-3039页

作者： Lola Zerbib Sophia Ladraa Antoine Fraissenon Charles Bayard Marina Firpion Quitterie Venot Sanela Protic Clément Hoguin Amandine Thomas Sylvie Fraitag jean-Paul Duong Sophie kaltenbach Estelle Balducci Coline Lefevre Patrick Villarese Vahid Asnafi Christine Broissand Nicolas Goudin Ivan Nemazanyy Gwennhael Autret Bertrand Tavitian Christophe Legendre Nadia Arzouk Veronique Minard-Colin Caroline Chopinet Michael Dussiot Denise MAdams Tristan Mirault Laurent Guibaud Paul Isenring Guillaume Canaud UniversitéParis Cité ParisFrance INSERM U1151 Institut Necker-Enfants MaladesParisFrance Service d’Imagerie Pédiatrique Hôpital Femme-Mère-EnfantHCLBronFrance CREATIS UMR 5220 Villeurbanne 69100France Service de Radiologie Mère-Enfant Hôpital NordSaint EtienneFrance Service d’Anatomie pathologique Hôpital Necker-Enfants MaladesAP-HPParisFrance Laboratoire d’Oncohématologie Hôpital Necker-Enfants MaladesAP-HPParisFrance Pharmacie Hôpital Necker-Enfants MaladesAP-HPParisFrance Necker Bio-Image Analysis INSERM US24/CNRS UMS 3633ParisFrance Platform for Metabolic Analyses Structure Fédérative de Recherche NeckerINSERM US24/CNRS UMS 3633ParisFrance Plateforme Imageries du Vivant Universitéde ParisPARCCINSERMParisFrance Service de Néphrologie Transplantation AdultesHôpital Necker-Enfants MaladesAP-HPParisFrance Service de Transplantation Hôpital La PitiéSalpétrièreAP-HPParisFrance Department of Pediatric and Adolescent Oncology INSERM 1015Gustave RoussyUniversitéParis-SaclayVillejuifFrance Service de Physiologie&Explorations Fonctionnelles Cardiovasculaires CHU de LilleLille 59000France INSERM U1163 Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutic ImplicationsLaboratoire d’Excellence GR-ExParisFrance Division of Oncology Comprehensive Vascular Anomalies ProgramChildren’s Hospital of PhiladelphiaPhiladelphiaPAUSA Service de Médecine Vasculaire hôpital Européen Georges-PompidouParisFrance Nephrology Research Group L’Hôtel-Dieu de Québec Research CenterDepartment of MedicineFaculty of MedicineLaval UniversityQuebecQC G1R2J6Canada Unitéde médecine translationnelle et thérapies ciblées Hôpital Necker-Enfants MaladesAP-HPParisFrance CNRS UMR8253 Institut Necker-Enfants MaladesParisFrance

Sporadic venous malformations are genetic conditions primarily caused by somatic gain-of-function mutation of PIk3CA or TEk,an endothelial transmembrane receptor signaling through *** malformations are associated with pain,bleedings,thrombosis,pulmonary embolism,esthetic deformities and,in severe cases,life-threatening *** authorized medical treatment exists for patients with venous ***,we created a genetic mouse model of PIk3CA-related capillary venous malformations that replicates patient *** showed that these malformations only partially signal through AkT *** compared the efficacy of different drugs,including rapamycin,a mTORC1 inhibitor,miransertib,an AkT inhibitor and alpelisib,a PI3kαinhibitor at improving the lesions seen in the mouse *** demonstrated the effectiveness of alpelisib in preventing vascular malformations’occurrence,improving the already established ones,and prolonging *** these findings,we were authorized to treat 25 patients with alpelisib,including 7 children displaying PIk3CA(n=16)or TEk(n=9)-related capillary venous malformations resistant to usual therapies including sirolimus,debulking surgical procedures or percutaneous *** assessed the volume of vascular malformations using magnetic resonance imaging(MRI)for each *** demonstrated improvement in all 25 *** malformations previously considered intractable were reduced and clinical symptoms were *** showed a decrease of 33.4%and 27.8%in the median volume of PIk3CA and TEk malformations respectively,over 6 months on *** conclusion,this study supports PI3kαinhibition as a promising therapeutic strategy in patients with PIk3CA or TEk-related capillary venous malformations.

关键词： PIk3CA malformations venous

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Testicular fine-needle aspiration for the assessmen＇ of intratesticular hormone concentrations

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Asian journal of Andrology 2016年第1期18卷 21-24页

作者： Ada P Lee Mara Y Roth jean-jacques Nya-Ngatchou kat Lin Thomas j Walsh Stephanie T Page Alvin M Matsumoto William j Bremner john k Amory Bradley D Anawalt Department of Medicine University of California San Francisco San Francisco CA USA Department of Medicine and Center for Research in Reproduction and Contraception University of Washington Seattle WA USA Department of Obstetrics and Gynecology University of Washington Seattle WA USA Department of Urology University of Washington Seattle WA USA Department of Medicine Geriatric Research Education and Clinical Center VA Puget Sound Health Care System Seattle WA USA.

Measurement of intratesticular sex steroid concentrations in men informs both the development of male hormonal contraceptives and the understanding of male infertility. Given the challenges of using invasive techniques to measure testicular hormone physiology, our group has used a minimally-invasive fine-needle aspiration technique to measure intratesticular hormones in normal healthy men. Herein, we present a post-hoc analysis of the safety and efficacy of testicular fine-needle aspiration （FNA） completed as part of six clinical trials. From 2001 through 2011, a total of 404 procedures were conducted among 163 research volunteers, 85.9% of which were successful in obtaining sufficient fluid for the measurement of intratesticular steroid concentrations. Pain was the most common side effect, with 36.8% of procedures associated with moderate procedural pain and 4.7% with severe procedural pain. Postprocedural pain was uncommon and abated within a few days. Mild local bruising occurred with 14.9% of procedures. Two serious adverse events （0.5%） required surgical intervention. The risk of an adverse event was not associated with age, body mass index, testicular size, or the volume of fluid aspirated. Testicular FNA to obtain fluid for measurement of intratesticular steroid concentrations frequently causes mild to moderate procedural pain, but serious adverse events occur rarely. Testicular FNA has been instrumental for defining human intratesticular hormone physiology and is a minimally-invasive, safe, effective method for obtaining fluid for research on testicular physiology and pathology.

关键词： male contraception physiology reproductive and urinary testis

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Synthesis, Molecular Structure, Anti-Plasmodial, Antimicrobial and Anti-Oxidant Screening of (E)-1-(Phthalazin-1-yl)-1-[(Pyridin-2-yl)Ethylidene]Hydralazine and 1-[2-(1-(pyridine-3- yl)ethylidene)hydrazinyl]phthalazine

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International journal of Organic Chemistry 2021年第3期11卷 91-105页

作者： Angelbert F. Awantu Godfred A. Ayimele jean jules k. bankeu Edouard A. Nantia Patrick V. T. Fokou Fabrice F. Boyom Emmanuel N. Nfor Bruno N. Lenta Silvère A. Ngouela Department of Chemistry The University of Bamenda Bambili Cameroon Department of Chemistry University of Buea Buea Cameroon Department of Biochemistry The University of Bamenda Bambili Cameroon Department of Biochemistry University of Yaoundé I Yaoundé Cameroon Department of Chemistry Higher Teachers’ Training College University of Yaoundé I Yaoundé Cameroon Department of Organic Chemistry Faculty of Science University of Yaoundé I Yaoundé Cameroon

Two new hydralazine hydrochloride-derived Schiff bases: (E)-1-(Phthalazin- 1-yl)-1-[(Pyridin-2-yl)Ethylidene]Hydralazine (PPEH), and 1-[2-(1-(pyridine- 3-yl)ethylidene)hydrazinyl]phthalazine (PEHP), were synthesized and partially characterized by spectroscopic and crystallographic methods including IR and X-ray. The single-crystal X-ray diffraction (SCXRD) analysis of PEHP indicates that the hydralazine moiety of both ligands possesses the exocyclic C=N bond. Both, PPEH and PEHP were tested as antimicrobials and antiparasites. Just PEHP could be considered as slightly antiplasmodial and antibacterial agent. In effect, PPEH showed low antimicrobial activity against one bacterial strain with Minimum Inhibitory Concentration (MIC) value of 250 μg/ml while PEHP showed very interesting activity against 18 out of 19 bacterial strains with MIC of 31.25 - 250 μg/ml compared to the standard drug, amoxicillin. PPEH and PEHP showed higher reducing activity on ferric ions compared to Vitamin C. On the other hand, both hidrazaline synthetized derivatives showed as better reducing agents than Vitamin C on ferric io

关键词： Schiff Base Hydralazine Hydrochloride Anti-Plasmodial Activity Antimicrobial Activity Anti-Oxidant Activity

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