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Tanning capacityof Tessmannia burttii extracts:thepotentialeco-friendlytanning agents fortheleatherindustry

journal of Leather Science and engineering 2021年第1期3卷 149-157页

作者： Cecilia R.China Stephen S.Nyandoro joan j.e.munissi Mihayo M.Maguta Michael Meyer Michaela Schroepfer Division of Textile and Leather Technologies Tanzania Industrial Research and Development OrganizationP.O.Box 2355Dar es SalaamTanzania Chemistry Department College of Natural and Applied SciencesUniversity of Dar es SalamP.O.Box 35061Dar es SalaamTanzania Department of environmental Planning Institute of Rural Development Planning(IRDP)P.O.Box 138DodomaTanzania FILK-Research Institute of Leather and Plastic Sheeting Meißner Ring 1-509599 FreibergGermany

In the present study,the tannins from stem and root barks of Tessmannia burttii Harms(Caesalpiniaceae),a plant species abundantly growing in Tanzania and other parts of Africa,were investigated for their suitability in hides *** powder was extracted at selected temperatures(30,50 and 80°C)and the influence of each temperature on the crosslinking capacity was *** interaction mechanism between hide powder collagen and the tannins was studied by Differential Scanning Calorimetry(DSC),trinitrobenzensulfonic(TNBS)acid assay and amino acid hydrolysis *** temperatures showed low influence on crosslinking capacity of the ***,extract obtained at 50°C exhibited best performance in terms of gap size between T onset and T *** stem bark extract yield was higher than that from the root bark,but both were within the recommended *** tannin content(61%)of *** stem bark extract was above recommended value(10%),whereas its total phenolic content and total flavonoic content were found to be above that of commercial Acacia mearnsii *** study of cross-linking parameters as a function of pH showed cross-linking to occur via a covalent mechanism at the basic amino ***,the bonds were not resistant to acid *** observed interaction mechanism indicated that tannins from stem and root barks of *** belong to the condensed tannin,similar to ***(black wattle),a commercial tannin source that was used in this study as a *** from this study depict that *** extracts are auspicious eco-friendly alternative source of vegetable tannins to overcome the use of chromium salts in the leather industry.

关键词： Tessmannia burttii Caesalpiniaceae Leather industry Vegetable tanning Tanning capacity

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evaluation of Antimycobacterial Activity of Higenamine Using Galleria mellonella as an In Vivo Infection Model

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Natural Products and Bioprospecting 2018年第1期8卷 63-69页

作者： Paul erasto Richard Sunguruma joan j.munissi Victor Wiketye Charles de Konig Atallah F.Ahmed National Institute for Medical Research P.O.Box 9653Dar Es SalaamTanzania Department of Chemistry University of Dar es SalaamDar Es SalaamTanzania School of Chemistry Witwatersrand UniversityJohannesburgRepublic of South Africa Department of Pharmacognosy College of PharmacyKing Saud UniversityP.O.Box 2457Riyadh 11451Saudi Arabia

The Phytochemical investigation on MeOH extract on the bark of Aristolochia brasiliensis Mart.&Zucc(Aristolochi-aceae)led to the isolation of major compound(1)as light brown grainy *** compound was identified as 1-(4-hydroxybenzyl)-1,2,3,4-tetrahydroisoquinoline-6,7-diol(higenamine)on the basis of spectroscopic analysis,including 1D and 2D NMR *** compound was evaluated for its antimycobacterial activity against Mycobacterium indicus pranii(MIP),using Galleria mellonella larva as an in vivo infection *** survival of MIP infected larvae after a single dose treatment of 100 mg/kg body weight of higenamine was 80%after 24 *** the compound exhibited a dose dependent activity,as evidenced by the reduction of colony density from 10^(5) to 10^(3) CFU for test concentrations of 50,100,150 and 200 mg/kg body weight *** IC50 value for higenamine was 161.6 mg/kg body weight as calculated from a calibration *** analysis showed that,a complete inhibition of MIP in the *** could be achieved at 334 mg/kg body *** the fact that MIP has been found to be highly resistant against isoniazid(INH)in an in vitro assay model,in this study the microbe was highly susceptible to this standard anti-TB *** isolation of higenamine from the genus Aristolochia and the method used to evaluate its in vivo antimycobacterial activity in *** are herein reported for the first time.

关键词： Aristolochia brasiliensis Galleria mellonella Higenamine Isoniazid Mycobacterium indicus pranii Antimycobacterial activity

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Introduction to IUMRS World Materials Summits

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Progress in Natural Science:Materials International 2011年第2期21卷 187-188页

作者： joan j.CARVAjAL Physics and Crystallography of Materials and Nanomaterials(FiCMA-FiCNA) Universitat Rovira i Virgili43007TarragonaSpain

The concept of IUMRS World Materials Summits initiated in *** Lian Zhou,president at that time of IUMRS,led several discussions during some informal 1UMRS meetings in Beijing,Xian,Ningbo and Shanghai with the various IUMRS member societies about the future possible developments of the Internationals Union for Materials Research *** one evening boat tour on a lake close to Shanghai in 2005 it emerged the suggestion of organizing conferences on the role of materials for future energy

关键词： World will

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In Silico evaluation of Anti-Malarial Agents from Hoslundia opposita as Inhibitors of Plasmodium falciparum Lactate Dehydrogenase (PfLDH) enzyme

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Computational Molecular Bioscience 2016年第2期6卷 23-32页

作者： Daniel M. Shadrack Stephen S. Nyandoro joan j. e. munissi egid B. Mubofu Chemistry Department Faculty of Natural and Applied Sciences St. John’s University of Tanzania Dodoma Tanzania Chemistry Department College of Natural and Applied Sciences University of Dar es Salaam Dar es Salaam Tanzania

Malaria has continued to be a health and economic problem in Africa and the world at large. Many anti-malarial drugs have been rendered ineffective due to the emergence of resistant strains of Plamodium falciparum. A key malaria parasite enzyme in glycolytic pathway, P. falciparum lactate dehydrogenase (PfLDH) is specially targeted for anti-malarial drugs development. Thus, the aim of this investigation was to determine the in silico inhibition effects of antimalarial compounds from Hoslundia opposita Vahl. namely hoslundin, hoslundal and hoslunddiol on PfLDH enzyme. The compounds were docked to the three-dimensional structure of PfLDH as enzyme using AutoDock Vina in PyRx virtual screening software. Binding affinity and position of the inhibitors were evaluated using PyMol software. The PfLDH enzyme showed two binding sites: the cofactors binding site (Site A) and secondary binding site (Site B). In the absence of the cofactor all ligands showed higher affinity than NADH, and were bound to the cofactors binding site (Site A). When docked in the presence of the cofactor, site B was the preferred binding site. Binding to cofactor site with higher binding energy than NADH suggests that these ligands could act as preferential competitive inhibitors of PfLDH. However, the binding to site B also suggests that they may be non-competitive allosteric inhibitors. Amino acid residues Gly99, Asn140, Phe100 and Thr97 were indicated to form hydrogen bonds with Hoslundin. Hoslunddiol showed hydrogen bonding with Thr97 and Met30, while Hoslundal formed hydrogen bond with Thr101 and Asn140.

关键词： PfLDH Hoslundin Hoslundal Hoslunddiol Anti-Malarial Docking

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An investigation of soil erosion and redistribution in a Mediterranean lowland agricultural catchment using caesium-137

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International journal of Sediment Research 2010年第1期25卷 1-16页

作者： joan eSTRANY Celso GARCIA Desmond e. WALLING Department of earth Sciences University of the Balearic Islands Department of Geography University of ExeterAmory Building

This study sought to contribute to an improved understanding of soil erosion and redistribution on Mediterranean agricultural land, where traditional soil conservation practices have been applied over millennia to provide effective protection of cultivated land. The study was undertaken in the Na Borges catchment, a groundwater-dominated lowland limestone basin (319 km2), located in the northeastern part of Mallorca, Spain. The average sediment yield from the basin, based on river sediment load data, is e 137Cs technique was used to quantify soil redistribution rates over the past 40 years and to identify the key factors involved in soil erosion and redistribution processes. To estimate erosion and deposition rates and to elucidate the main factors affecting soil redistribution, samples were collected from six slope transects representative of the local land use and slope gradients and the presence or absence of soil conservation practices. A mass balance and a profile distribution conversion model were used for cultivated areas and areas of natural vegetation, respectively, to derive point estimates of the soil redistribution rates from the 137Cs inventories measured for individual soil bulk cores. In areas without soil conservation practices, the estimated mean soil erosion rates ranged from 12.7 to 26.4 t/ha·yr, which correspond to the slight and moderate erosion classes. The erosivity of Mediterranean climatic conditions combined with the influence of agricultural practices and slope gradient on soil erosion, represent the main factors responsible for the variation of soil losses documented for the cultivated land located in downslope areas, in the absence of soil conservation practices. Deposition dominated for those transects affected by soil conservation practices, with rates ranging between 18.8 and 96.6 t/ha·yr. However, this situation does not mean that soil conservation measures retain all the sediment, but rather that agriculture and urba

关键词： Soil erosion 137Cs Traditional soil conservation practices Agricultural land Mediterranean

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Plasmon-induced dual-wavelength operation in a Yb^(3+) laser

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Light(Science & Applications) 2019年第1期8卷 1042-1050页

作者： Laura Sanchez-Garcia Mariola O.Ramirez Rosa Maria Sole joan j.Carvajal Francesc Diaz Luisa e.Bausa Deparment Fisica de Materiales Instituto Nicolas Cabrera and Condensed Matter Physics Center(IFIMAC)Universidad Autonoma de Madrid28049 MadridSpain Universitat Rovira i Virgili Departament Quimica Fisica i InorganicaFisica i Cristal·lografia de Materials i Nanomaterials(FiCMA-FiCNA)-EMaSE-43007 TarragonaSpain

expanding the functionalities of plasmon-assisted lasers is essential for emergent applications in nanoscience and ***,we report on a novel ability of plasmonic structures to induce dual-wavelength lasing in the near-infrared region in a Yb^(3+) solid-state *** means of the effects of disordered plasmonic networks deposited on the surface of a Yb^(3+)-doped nonlinear RTP crystal,room-temperature dual-wavelength lasing,with a frequency difference between the lines in the THz range,is *** dual-wavelength laser is produced by the simultaneous activation of two lasing channels,namely,an electronic-and a phonon-terminated laser *** latter is enabled by the out-of-plane field components that are generated by the plasmonic structures,which excite specific Raman ***,multiline radiation at three different wavelengths is demonstrated in the visible spectral region via two self-frequency conversion processes,which occur in the vicinities of the plasmonic *** results demonstrate the potential of plasmonic nanostructures for inducing drastic modifications in the operational mode of a solid-state laser and hold promise for applications in a variety of fields,including multiplexing,precise spectroscopies,and THz radiation generation via a simple and cost-effective procedure.

关键词： laser lasing dual

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Detection of antibiotic resistance toxigenic Clostridium difficile in processed retail lettuce

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Food Quality and Safety 2018年第1期2卷 37-41页

作者： Yi Han joan King Marlene e.janes School of Nutrition and Food Sciences Louisiana State University Agricultural CenterBaton RougeLouisianaUSA

Objectives:Clostridium difficile is the major cause of infectious diarrhoea in humans after antimicrobial *** difficile has been isolated from food animals and *** main purpose of this study was to characterize *** isolated from retail lettuce and determine the antibiotic resistance using five common clinical-selected antibiotics(metronidazole,vancomycin,clindamycin,erythromycin,and cefotaxime).Materials and Methods:Lettuce samples(grown in California,Arkansas,and Louisiana)were purchased from retail ***:Toxigenic *** was isolated from 13.8 per cent(41/297)of the lettuce *** the toxigenic isolates,only 82.9 per cent(34/41)produced toxin B,17.1 per cent(7/41)produced both toxin A and toxin B,and two of the Louisiana *** isolates were identified as ribotype *** the treatment of the five antibiotics,the virulence *** isolates were identified as having antibiotic resistance to metronidazole,vancomycin,and ***:The present study reports the highest prevalence of toxigenic *** in US retail *** antibiotic resistance to metronidazole,vancomycin,and erythromycin of the isolated *** from retail lettuces could lead to public health concerns.

关键词： Clostridium difficile lettuce toxigenic toxin A toxin B antibiotic.

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Assembly and electrochemical testing of renewable carbon-based anodes in SIBs:A practical guide

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journal of energy Chemistry 2022年第12期75卷 457-477,I0012页

作者： Darío Alvira Daniel Antorán joan jManyà Aragón Institute of engineering Research(I3A) Thermochemical Processes GroupUniversity of ZaragozaEscuela Politécnica Superior22071 HuescaSpain

Sodium-ion batteries(SIBs)are considered as a promising candidate to replace lithium-ion batteries(LIBs)in large-scale energy storage *** sodium resources and similar working principles make this technology attractive to be implemented in the near ***,the development of high-performance carbon anodes is a focal point to the upcoming success of SIBs in terms of power density,cycling stability,and *** knowledge in electrochemical and physicochemical techniques is required to properly evaluate the anode performance and move it in the right *** review aims at providing a comprehensive guideline to help researchers from different backgrounds(e.g.,nanomaterials and thermochemistry)to delve into this *** main components,lab configurations,procedures,and working principles of SIBs are ***,a detailed description of the most used electrochemical and physicochemical techniques to characterize electrochemically active materials is provided.

关键词： Sodium-ion battery Anode Hard carbon electrochemical techniques Carbon characterization

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Feasibility of using pedometers in a state-based surveillance system：2014 Arizona Behavioral Risk Factor Surveillance System

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journal of Sport and Health Science 2018年第1期7卷 34-41页

作者： Alberto Flórez-Pregonero janet e.Fulton joan M.Dorn Barbara e.Ainsworth School of Nutrition and Health Promotion College of Health Solutions Arizona State University Phoenix AZ 85004 USA Pontificia Universidad javeriana Bogot6 110231 Colombia Physical Activity and Health Branch Division of Nutrition Physical Activity and Obesity Center for Chronic Disease Prevention and Health Promotion U.S. Centers for Disease Control and Prevention Atlanta GA 30340 USA Department of Community Health and Social Medicine City University of New York (CUNY) School of Medicine New York NY 10031 USA

Background: Despite their utility in accessing ambulatory movement, pedometers have not been used consistently to monitor physical activity in U.S. surveillance systems. This study was designed to determine the feasibility of using pedometers to assess daily steps taken in a sub-sample of adults from Maricopa County who completed the 2014 Arizona Behavioral Risk Factor Surveillance System ***: Respondents were sent an Omron Hj324 U pedometer, a logbook to record steps taken, and a walking questionnaire. The pedometer was worn for 7 days. Feasibility was assessed for acceptability(interest in study), demand(procedures followed correctly), implementation(time to complete study), and practicality(cost).Results: Acceptability was modest with 23.9%(830/3476) agreeing to participate. Among those participating(92.9%; 771/830), 50.1%(386/771)returned the logbook. Demand was modest with 39.3%(303/771) of logbooks returned with valid data. Implementation represented 5 months to recruit participants. The cost to obtain valid step-count data was USD61.60 per person. An average of 6363 ± 3049 steps/day were taken with most participants classified as sedentary(36.0%) or low active(35.6%).Conclusion: The feasibility of using pedometers in a state-based surveillance system is modest at best. Feasibility may potentially be improved with easy-to-use pedometers where data can be electronically downloaded.

关键词： Assessment Measurement Physical activity Public health

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脊髓切片中运动神经元的膜片箝技术研究:一种分析药物作用的高效工具(英文)

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Acta Pharmacologica Sinica 2000年第6期21卷 29-37页

作者： joan j KeNDIG CA 94305 Department of Anesthesia Stanford University School of Medicine USA

AIM: To develop a tool for detailed analysis of spirally acting anesthetic and analgesic agents. MeTHODS: Studies were done on visually identified motor neurons in 400 uuuuuuuum thick spinal cord slices from 14-23 d old rats using patch clamp techniques. ethanol was used as a prototype general anesthetic agent. ReSULTS: Cell bodies in the ventrolateral horn identified as motor neurons by retrograde fluorescent labeling had a mean dimension of 32 ± 5 /Mm (x ± s, n = 25). Mean resting potential was - 62. 8 ± 2. 4 mV; input resistance was 44±24 MΩ (n = 19). Threshold was -44± 7 mV, and action potential amplitude 101 ± 9 mV from baseline. ethanol concentrations at and below 50-200 mmol/L decreased motor neuron excitability to the injected current; there was no effect on resting potential, but a variable reversible increase in input resistance. ethanol re-versibly depressed the excitatory postsynaptic potential, with a dose-response relationship similar to that previously observed for the population e

关键词：脊髓运动神经元乙醇醇类全身麻醉突触后机制

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