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Extraction of a novel tanning agent from indigenous plant bark and its application in leather processing

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Journal of Leather Science and Engineering 2022年第1期4卷 253-267页

作者： Raju Kumar Das Al Mizan fatema Tuj zohra Sobur Ahmed Khondoker Shahin Ahmed Hemayet Hossain Institute of Leather Engineering and Technology(ILET) University of Dhaka44-50HazaribaghDhaka 1209Bangladesh Department of Leather Engineering Khulna University of Engineering&Technology(KUET)Khulna 9203Bangladesh Department of Leather Engineering Faculty of EngineeringEge University35100 BornovaIzmirTurkey BCSIR Laboratories Chemical Research DivisionBangladesh Council of Scientific and Industrial Research(BCSIR)DhanmondiDhaka 1205Bangladesh

The use of vegetable tanning materials in leather processing has drawn attention as an alternative to basic chromium sulphate for its natural abundance and environmental aspects. In this work, an attempt has been made to extract veg-etable tannins from Xylocarpus granatum bark using different solvents (e.g., water, methanol, ethanol, and chloroform) and compare with conventional vegetable tanning agents such as mimosa and quebracho. The highest extraction efficiency was observed 31.22% by methanol. The presence of tannin content and polyphenolic compounds, e.g. (-)epicatechin (503 mg/100 g dry extract), catechin hydrate (218 mg/100 g dry extract), catechol (29 mg/100 g dry extract) were ensured by UV-Vis, FT-IR spectroscopy and HPLC. Again, condensed tannins, moisture content, and pH of the methanol extracted tannin were found 47.80%, 5.82%, and 3.97 respectively. The leather tanned by Xylocar-pus granatum tannin showed a shrinkage temperature of 86.34 ± 1.52 °C. Other properties such as tensile strength, tear strength, grain cracking load, and distention at grain cracking were comparable to conventional vegetable- tanned leather. The cross-sectional morphology of the tanned leathers was also characterized by scanning electron microscopy (SEM) which revealed a compact structure of the leather fibers. In light of the findings from the study, X. granatum bark tannin could be a well alternative to chromium and a new source of vegetable tannin for the leather industry.

关键词： Vegetable tanning agent Strength properties Shrinkage temperature Chrome-free leather Alternative tannin Xylocarpus granatum

Harnessing machine learning tools for water quality assessment in the Kebili shallow aquifers,Southwestern Tunisia

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Acta Geochimica 2024年第6期43卷 1065-1086页

作者： zohra Kraiem Kamel Zouari Rim Trabelsi Laboratory of Radio-Analyses and Environment National Engineering SchoolUniversity of Sfax11733038 SfaxTunisia

An integrated method that implements multivariate statistical analysis and ML methods to evaluate groundwater quality of the shallow aquifers of the Djerid and Kebili district,Southern Tunisia,was *** evaluation of their suitability for irrigation and/or drinking purposes is necessary.A comprehensive hydrochemical assessment of 52 samples with entropy weighted water quality index(EWQI)was also *** water parameters were calculated to ascertain the potential use of those resources in irrigation and *** analysis showed two main components with Dim1(variance=62.3%)and Dim.2(variance=22%),due to the bicarbonate,dissolution,and evaporation and the intrusion of drainage *** evaluation of water quality has been carried out using EWQI *** calculated EWQI for the Djerid and Kebili waters(i.e.,52 samples)varied between 7.5 and 152.62,indicating a range of 145.12.A mean of 79.12 was lower than the median(88.47).From the calculation of EWQI,only 14 samples are not suitable for irrigation because of their poor to extremely poor quality(26.92%).The bivariate plot showed high correlation for EWQI~TH(r=0.93),EWQI~SAR(r=0.87),indicating that water quality depended on those *** erent ML algorithms were successfully applied for the water quality classifi *** results indicated high prediction accuracy(SVM>LDA>ANN>kNN)and perfect classifi cation for kNN,LDA and Naive *** the purposes of developing the prediction models,the dataset was divided into two groups:training(80%)and testing(20%).To evaluate the models’performance,RMSE,MSE,MAE and R^(2) metrics were ***(R^(2)=0.9359,MAE=6.49,MSE=79.00)and LDA(accuracy=97.56%;kappa=96.21%)achieved high ***,linear regression indicated high correlation for both training(R^(2)=0.9727)and testing data(0.9890).This well confi rmed the validity of LDA algorithm in predicting water *** validation showed a high accuracy(92.31%),high sensitivity(89.47%)an

关键词： Water-resources management Multivariate analysis Machine learning Kebili and Djerid shallow aquifers EWQI Water classification

Partially Overlapping Channel Assignment Using Bonded and Non-Bonded Channels in IEEE 802.11n WLAN

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Computers, Materials & Continua 2022年第5期71卷 3161-3178页

作者： MdSelim Al Mamun fatema Akhter Graduate School of Natural Science and Technology Okayama UniversityOkayama700-8530Japan Computer Science and Engineering Jatiya Kabi Kazi Nazrul Islam UniversityMymensingh2224Bangladesh

Nowadays,wireless local area network(WLAN)has become prevalent Internet access due to its low-cost gadgets,flexible coverage and hasslefree simple wireless *** facilitates wireless Internet services to users with mobile devices like smart phones,tablets,and laptops through deployment of multiple access points(APs)in a network *** AP operates on a frequency band called *** wireless standard such as IEEE 802.11n has a limited number of channels where frequency spectrum of adjacent channels overlaps partially with each *** a crowded environment,users may experience poor Internet services due to channel collision i.e.,interference from surrounding APs that affects the performance of the WLAN ***,it becomes a challenge to maintain expected performance in a crowded environment.A mathematical model of throughput considering interferences from surrounding APs can play an important role to set up a WLAN system *** set up,assignment of channels considering interference can maximize network *** this paper,we investigate the signal propagation of APs under interference of partially overlapping channels for both bonded and non-bonded ***,a throughput estimation model is proposed using difference of operating channels and received signal strength indicator(RSSI).Then,a channel assignment algorithm is introduced using proposed throughput estimation ***,the efficiency of the proposal is verified by numerical experiments using *** results show that the proposal selects the best channel combination of bonded and non-bonded channels that maximize the performance.

关键词： Wireless local area network partially overlapping channel throughput estimation model channel assignment algorithm

Prerequisite Relations among Knowledge Units:A Case Study of Computer Science Domain

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Computer Modeling in Engineering & Sciences 2022年第12期133卷 639-652页

作者： fatema Nafa Amal Babour Austin Melton Department of Computer Science Salem State UniversitySalemMA 01970USA Information Systems Department Faculty of Computing and Information TechnologyKing Abdulaziz UniversityJeddah21589Saudi Arabia Department of Computer Science Kent State UniversityKentOH 44240USA

The importance of prerequisites for education has recently become a promising research *** work proposes a statistical model for measuring dependencies in learning resources between knowledge *** are expected to present knowledge units in a semantically well-organized manner to facilitate students’understanding of the *** proposed model reveals how inner concepts of a knowledge unit are dependent on each other and on concepts not in the knowledge *** help understand the complexity of the inner concepts themselves,WordNet is included as an external knowledge base in *** goal is to develop a model that will enable instructors to evaluate whether or not a learning regime has hidden relationships which might hinder students’ability to understand the *** evaluation,employing three textbooks,shows that the proposed model succeeds in discovering hidden relationships among knowledge units in learning resources and in exposing the knowledge gaps in some knowledge units.

关键词： Knowledge graph text mining knowledge unit graph mining

Risk estimation of chronic kidney disease in a leptospirosis endemic area: A case-control study from south Andaman Islands of India

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Asian Pacific Journal of Tropical Medicine 2023年第10期16卷 463-471页

作者： Ambreen fatema Manjunatha Ramu Paluru Vijayachari ICMR-Regional Medical Research Centre Port BlairPost Bag No.13DollygunjPort Blair 744101Andaman&Nicobar IslandsIndia

Objective:To estimate the risk of chronic kidney disease in patients with ***:All reported(41890)and later confirmed leptospirosis(1990)cases from 2010-2020 were traced by universal sampling.386 Laboratory-confirmed leptospirosis cases were enrolled and 413 age,gender,area,and occupation matched healthy persons were included as *** including socio-demographic characteristics,medical history,and health-related behaviours were compared between the two groups and association between these variables and reduced estimated glomerular filtration rate(eGFR)was analyzed with multiple linear ***:The median of eGFR was 49.0(27.0,75.0)mL/min/1.73 m^(2) in the cases and 96.0(72.0,121.0)mL/min/1.73 m^(2) in the controls,showing significant differences(P<0.001).Bivariate analysis showed that leptospirosis seropositivitiy,repeat leptospirosis infection,diabetes,male gender,working in field(sun exposure),COVID-19 infection and smoking had statistically significant association with reduced *** seropositivity had negative effects on *** linear regression confirmed that leptospirosis seropositivity had negative effects on eGFR(unstandardised β coefficients=−30.86,95%CI−49.7 to−11.9,P<0.001).Conclusions:Chronic kidney disease is a complex disease with multiple risk factors *** to leptospirosis is one of the essential factors in accelerating its progression.

关键词： Chronic kidney disease Endemic leptospirosis Estimated glomerular filtration rate(eGFR)

SEIR-SW, Simulation Model of Influenza Spread Based on the Small World Network

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Tsinghua Science and Technology 2015年第5期20卷 460-473页

作者： Fatima-zohra Younsi Ahmed Bounnekar Djamila Hamdadou Omar Boussaid Department of Computer Science Faculty of SciencesUniversity of Oran the ERIC(Entrepts Reprèsentation et Ingènierie des Connaissances)Lab University of Lumire Lyon 2Lyon 69676 France Polytechnic School University of Claude Bernard Lyon1 Lyon 69622 France

This study modeled the spread of an influenza epidemic in the population of Oran, Algeria. We investigated the mathematical epidemic model, SEIR（Susceptible-Exposed-Infected-Removed）, through extensive simulations of the effects of social network on epidemic spread in a Small World（SW） network, to understand how an influenza epidemic spreads through a human population. A combined SEIR-SW model was built, to help understand the dynamics of infectious disease in a community, and to identify the main characteristics of epidemic transmission and its evolution over time. The model was also used to examine social network effects to better understand the topological structure of social contact and the impact of its properties. Experiments were conducted to evaluate the combined SEIR-SW model. Simulation results were analyzed to explore how network evolution influences the spread of desease, and statistical tests were applied to validate the model. The model accurately replicated the dynamic behavior of the real influenza epidemic data, confirming that the susceptible size and topological structure of social networks in a human population significantly influence the spread of infectious diseases. Our model can provide health policy decision makers with a better understanding of epidemic spread,allowing them to implement control measures. It also provides an early warning of the emergence of influenza epidemics.

关键词： SEIR-SW(Susceptible-Exposed-Infected-Removed within Small World network) statistical analysis methods Social Network Analysis(SNA) visualization of SNA disease outbreaks

Characterization of organic matter deposited in the oriental zone from Moknine hypersaline environment, oriental Tunisia

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Chinese Journal Of Geochemistry 2005年第4期24卷 345-351页

作者： Raja CHAIRI zohra EL ASMI DJELLOULI Laboratoire de Ressources Minerales et Environnement Faculté des Sciences de Tunis 2092 Univ. Tunis El Manar Tunisie Laboratoire de Ressources Minerales et Environnement Faculté des Sciences de Tunis 2092 Univ. Tunis El Manar Tunisie

The geochemistry data show that the total organic carbon (TOC) contents are high in the surface sediments in the eastern part of the Moknine’s Sebkha. Low decreasing of organic matter (OM) with increasing depth indicates the good preservation of OM in modern sediments. “Lignite levels” inserted in the sand sequence and deposited at the edge and in the intermediate zone are considered as lithologic and organic markers. It is characterized by high TOC and poor hydrogen index (HI), indicating a higher plant origin and good preservation of OM in thin beds under anoxic condition.; In all samples low values of HI are typical for strong terrigenous input in the Sebkha. Gas chromatography (GC) of saturate fraction showed that OM in the border zone is provided from plants but in the central zone OM is a mixture of terrestrial fraction and little fraction from microalgae. The study of free lipids indicated that this environment was influenced by intense bacterial and microbial activities, as evidenced by the abundance of n-alkanes and nC-{18}-nC-{22}.

关键词：突尼斯地球化学有机物质褐煤地质条件

Multiple Solutions for an Elliptic Equation with Hardy Potential and Critical Nonlinearity on Compact Riemannian Manifolds

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Journal of Partial Differential Equations 2024年第1期37卷 1-24页

作者： MALIKI Youssef TERKI Fatima zohra Laboratoire Systemes Dynamiques et Applications Department of Mathematics `University Aboubekr Belka¨id of TlemcenTlemcenAlgeria.

We prove the existence of multiple solutions of an elliptic equation with critical Sobolev growth and critical Hardy potential on compact Riemannian manifolds.

关键词： Riemannian manifolds Yamabe equation Hardy potential.

Navigating the genomic instability mine field of osteosarcoma to better understand implications of non-coding RNAs

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BIOCELL 2022年第10期46卷 2177-2193页

作者： KANIZ fatema ZACHARY LARSON JARED BARROTT Biomedical and Pharmaceutical Science Idaho State UniversityPocatello83209USA

Osteosarcoma is one of the most genomically complex cancers and as result,it has been difficult to assign genomic aberrations that contribute to disease progression and patient outcome consistently across *** potential source for correlating osteosarcoma and genomic biomarkers is within the non-coding regions of RNA that are differentially ***,it is unsurprising that a cancer classification that is fraught with genomic instability is likely to have numerous studies correlating non-coding RNA expression and function have been published on the *** review undertakes the formidable task of evaluating the published literature of noncoding RNAs in *** is not the first review on this topic and will certainly not be the *** review is organized with an introduction into osteosarcoma and the epigenetic control of gene expression before reviewing the molecular function and expression of long non-coding RNAs,circular RNAs,and short non-coding RNAs such as microRNAs,piwi RNAs,and short-interfering *** review concludes with a review of the literature and how the biology of non-coding RNAs can be used therapeutically to treat cancers,especially *** conclude that non-coding RNA expression and function in osteosarcoma is equally complex to understanding the expression differences and function of coding RNA and proteins;however,with the added lens of both coding and non-coding genomic sequence,researchers can begin to identify the patterns that consistently associate with aggressive osteosarcoma.

关键词： Osteosarcoma Epigenetics Long non-coding RNA Circular RNA MicroRNA