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Advancements in Polymer Science: Synthesis, Characterization, and Biomedical Applications of Homopolymers and Copolymers

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Open Journal of Polymer Chemistry 2024年第3期14卷 167-198页

作者： Anaif M. Alhewaitey ishrat khan Emmanuel Ramsey Buabeng Department of Chemistry Clark Atlanta University Atlanta USA Department of Chemistry University of Tabuk Tabuk Saudi Arabia Department of Chemistry Georgia State University Atlanta GA USA

Polymer science encompasses a different range of materials critical to industries spanning from packaging to biomedicine. Understanding the synthesis, characterization, and applications of common homopolymers and copolymers is fundamental to advancing polymer research and development. In this comprehensive review, we explore various preparation methods, including free radical, anionic, and cationic polymerization, utilized for synthesizing homopolymers and copolymers. Furthermore, we investigate solvent choices commonly employed for polymer characterization, ranging from neat conditions, polar protic and polar aprotic solvents. We also explored characterization techniques, including Fourier Transform Infrared Spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR), Atomic Force Microscopy (AFM), Differential Scanning Calorimetry (DSC), and Thermogravimetric Analysis (TGA). In addition to industrial applications, we highlight the diverse biological applications of homopolymers, poly(2-hydroxyethyl methacrylate) (pHEMA) and polystyrene, which find its extensive use in biomedicine. By synthesizing and analyzing this wealth of information, this review aims to provide a comprehensive understanding of the synthesis, characterization, and applications of homopolymers and copolymers, with a particular focus on their biological applications. This holistic approach not only contributes to advancements in polymer science and technology but also fosters innovation in biomedicine, ultimately benefiting human health and well-being.

关键词： Homopolymer Copolymer Poly(2-hydroxyethyl methacrylate) (pHEMA) Polystyrene Free Radical Polymerization Atomic Force Microscopy Solvent Polarity

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Synthesis and Characterization of Poly Styrene-Co-Poly 2-Hydroxyethylmethacrylate (HEMA) Copolymer and an Investigation of Free-Radical Copolymerization Propagation Kinetics by Solvent Effects

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Open Journal of Polymer Chemistry 2024年第1期14卷 63-93页

作者： Anaif M. Alhewaitey ishrat khan Naif M. Alhawiti Department of Chemistry Clark Atlanta University Atlanta USA Department of Chemistry University of Tabuk Tabuk Saudi Arabia CAHFS University of California Davis Davis California

A series of homo and copolymers of styrene (ST) and 2-hydroxyethyl methacrylate (HEMA) in three different media (bulk, tetrahydrofuran, and benzene) have been investigated by free radical polymerization method. The samples obtained from the synthesis were characterized by Fourier Transform-Infrared spectroscopy (FT-IR), proton nuclear magnetic resonance spectroscopy (1H NMR), atomic force microscopy (AFM), and differential scanning calorimetry (DSC). The results show that the synthesis of the polymers is more feasible under neat conditions rather than solvent directed reaction. Moreover, the DSC data shows that the polystyrene obtained is amorphous in nature and therefore displayed only a glass transition signal rather than crystallization and melting peaks. In addition, this study indicates that homolopolymerization of styrene via free radical polymerization tends to be preferable in less polar solvents like THF than in non-polar solvents like benzene. Benzene might destabilize the formation of the reactive radicals leading to the formation of the products. In summary, the homolpolymerization of styrene is more feasible than the homopolymerization 2-hydroxyethyl methacrylate under the experimental setup used. Styrene is more reactive than 2-hydroxyethyl methacrylate than free radical polymerization reaction due in part of the generation of the benzylic radical intermediate which is more stable leading to the formation of products than alkyl radical which are less stable. Furthermore, polymerization of styrene under neat conditions is preferable in solvent-assisted environments. The choice of solvent for the synthesis of these polymers is crucial and therefore the selection of solvent that leads to the formation of a more stable reaction intermediate is more favorable. It is worth noting that the structure of the proposed copolymer consists of a highly polar and hydrophilic monomer, 2-hydroxyethyl methacrylate and a highly non-polar and hydrophobic monome

关键词： 2-Hydroxyethyl Methacrylate Polymerization

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X-ray Image-Based COVID-19 Patient Detection Using Machine Learning-Based Techniques

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Computer Systems Science & Engineering 2022年第11期43卷 671-682页

作者： Shabana Habib Saleh Alyahya Aizaz Ahmed Muhammad Islam Sheroz khan ishrat khan Muhammad Kamil Department of Information Technology College of ComputerQassim UniversityBuraidah52571Saudi Arabia Department of Electrical Engineering College of Engineering&Information TechnologyOnaizah CollegesOnaizah51911Saudi Arabia Digital Image Processing Lab Islamia CollegePeshawar25120KPKPakistan Department of Computer Science College of Computer and Information SciencesPrince Sultan UniversityRiyadh11586Saudi Arabia Department of Electrical Engineering National University of Computer and Emerging SciencesPeshawarPakistan

In early December 2019,the city of Wuhan,China,reported an outbreak of coronavirus disease(COVID-19),caused by a novel severe acute respiratory syndrome coronavirus-2(SARS-CoV-2).On January 30,2020,the World Health Organization(WHO)declared the outbreak a global pandemic *** the face of the COVID-19 pandemic,the most important step has been the effective diagnosis and monitoring of infected *** COVID-19 using Machine Learning(ML)technologies can help the health care unit through assistive diagnostic suggestions,which can reduce the health unit's burden to a certain *** paper investigates the possibilities of ML techniques in identifying/detecting COVID-19 patients including both conventional and exploring from chest X-ray images the effect of viral *** approach includes preprocessing,feature extraction,and ***,the features are extracted using the Histogram of Oriented(HOG)and Local Binary Pattern(LBP)feature ***,for the extracted features classification,six ML models of Support Vector Machine(SVM)and K-Nearest Neighbor(KNN)is *** results show that the diagnostic accuracy of random forest classifier(RFC)on extracted HOG plusLBP features is as high as 94%followed by SVM at 93%.The sensitivity of the K-nearest neighbour model has reached an accuracy of 88%.Overall,the predicted approach has shown higher classification accuracy and effective diagnostic *** is a highly useful tool for clinical practitioners and radiologists to help them in diagnosing and tracking the cases of COVID-19.

关键词： Image pre-processing detection classification x-ray images filter

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Connective tissue growth factor expression hints at aggressive nature of colorectal cancer

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World Journal of Gastroenterology 2022年第5期28卷 547-569页

作者： ishrat Parveiz Bhat Tahseen Bilal Rather Irfan Maqbool Gowhar Rashid Kulsum Akhtar Gulzar A Bhat Fazl Q Parray Besina Syed ishrat Younas khan Mohsin Kazi Muhammad D Hussain Mudassar Syed Department of Clinical Biochemistry Sher-I-Kashmir Institute of Medical SciencesSrinagar 190011Jammu and KashmirIndia Department of General Surgery Sher-I-Kashmir Institute of Medical SciencesSrinagar 190011Jammu and KashmirIndia Department of Pathology Sher-I-Kashmir Institute of Medical SciencesSrinagar 190011Jammu and KashmirIndia Department of Pharmaceutics College of PharmacyKing Saud UniversityPO Box 2457Riyadh 11451Saudi Arabia Department of Pharmaceutical and Biomedical Sciences California Health Sciences UniversityCaliforniaCA 93612United States

BACKGROUND Connective tissue growth factor(CTGF)is a mediator of transforming growth factor-beta signaling and plays a key role in connective tissue remodeling,inflammatory processes and fibrosis in various illnesses including *** To investigate the role of CTGF in colorectal cancer(CRC)progression and to compare the CTGF expression with different clinicopathological *** Real-time polymerase chain reaction,immunohistochemistry and Western blotting was performed to evaluate the CTGF expression and the results were statistically analyzed against the clinicopathological variables of patient data using STATA software version *** CTGF expression levels in tumor specimens were significantly higher than their paired normal *** higher protein expression levels showed a significant association with smoking,staging,tumor grade,invasion depth,necrosis of tumor tissue,and both lymphovascular and perineural *** per the cox regression model and classification tree analysis,tumor-nodemetastasis stage and perineural invasion were important predictors for CTGF expression and prognosis of CRC *** analysis indicated that CTGF overexpression was associated with poorer overall and disease-free *** Expression of CTGF was increased in CRC and was linked with poor overall and disease-free survival of CRC *** findings support prior observations and thus CTGF may be a possible prognostic marker in CRC.

关键词： Connective tissue growth factor Quantitative real time polymerase chain reaction Immunohistochemistry Western blotting Colorectal cancer

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Modulation of p75 neurotrophin receptor mitigates brain damage following ischemic stroke in mice

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Neural Regeneration Research 2024年第10期19卷 2093-2094页

作者： Golnoush Mirzahosseini Tauheed ishrat Department of Anatomy and Neurobiology College of MedicineThe University of Tennessee Health Science CenterMemphisTNUSA Pharmaceutical Sciences College of PharmacyThe University of Tennessee Health Science CenterMemphisTNUSA Neuroscience Institute The University of Tennessee Health Science CenterMemphisTNUSA

Stroke is a significant leading cause of death and disability in the United States(Tsao et al.,2022).Approximately 87% of strokes fall into the ischemic category,mainly caused by arterial blockage(Jayaraj et al.,2019).Although the only FDA-approved effective medication is tissue plasminogen activator(tPA),it should be administrated within 4.5 hours of ischemic ***,tPA has been an integral part of managing acute ischemic stro ke.

关键词： damage arterial death p75

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Dredged marine soil stabilization using magnesia cement augmented with biochar/slag

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 1000-1017页

作者： Chikezie Chimere Onyekwena Qi Li Yong Wang ishrat Hameed Alvi Wentao Li Yunlu Hou Xianwei Zhang Min Zhang State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China School of Civil Engineering Architecture and EnvironmentHubei University of TechnologyWuhan430068China School of Urban Construction Wuhan University of Science and TechnologyWuhan430065China School of Civil Engineering and Archtitecture Henan UniversityKaifeng475001China

Dredged marine soils(DMS)have poor engineering properties,which limit their usage in construction *** research examines the application of reactive magnesia(rMgO)containing supplementary cementitious materials(SCMs)to stabilize DMS under ambient and carbon dioxide(CO_(2))curing *** proprietary experimental tests were conducted to investigate the stabilized ***,the carbonation-induced mineralogical,thermal,and microstructural properties change of the samples were *** findings show that the compressive strength of the stabilized DMS fulfilled the 7-d requirement(0.7-2.1 MPa)for pavement and building *** rMgO with SCMs such as biochar or ground granulated blast-furnace slag(GGBS)altered the engineering properties and particle packing of the stabilized soils,thus influencing their *** increased the porosity of the samples,facilitating higher CO_(2) uptake and improved ductility,while GGBS decreased porosity and increased the dry density of the samples,resulting in higher *** addition of SCMs also enhanced the water retention capacity and modified the pH of the *** analysis revealed that the hydrated magnesium carbonates precipitated in the carbonated samples provided better cementation effects than brucite formed during rMgO ***,incorporating SCMs reduced the overall global warming potential and energy demand of the rMgO-based *** biochar mixes demonstrated lower toxicity and energy ***,the rMgO and biochar blend can serve as an environmentally friendly additive for soft soil stabilization and permanent fixation of significant amounts of CO_(2) in soils through mineral carbonation,potentially reducing environmental pollution while meeting urbanization needs.

关键词： Dredged marine soil CO_(2)uptake Reactive magnesia Biochar Ground granulated blast-furnace slag

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Sentiment Analysis of Low-Resource Language Literature Using Data Processing and Deep Learning

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Computers, Materials & Continua 2024年第4期79卷 713-733页

作者： Aizaz Ali Maqbool khan Khalil khan Rehan Ullah khan Abdulrahman Aloraini Department of IT and Computer Science Pak-Austria Fachhochschule:Institute of Applied Sciences and TechnologyHaripur22620Pakistan Software Competence Center Hagenberg Softwarepark 32aHagenberg4232Austria Department of Computer Science School of Engineering and Digital SciencesNazarbayev UniversityAstana010000Kazakhstan Department of Information Technology College of ComputerQassim UniversityP.O.Box 1162BuraydahSaudi Arabia

Sentiment analysis, a crucial task in discerning emotional tones within the text, plays a pivotal role in understandingpublic opinion and user sentiment across diverse *** numerous scholars conduct sentiment analysisin widely spoken languages such as English, Chinese, Arabic, Roman Arabic, and more, we come to grapplingwith resource-poor languages like Urdu literature which becomes a challenge. Urdu is a uniquely crafted language,characterized by a script that amalgamates elements from diverse languages, including Arabic, Parsi, Pashtu,Turkish, Punjabi, Saraiki, and more. As Urdu literature, characterized by distinct character sets and linguisticfeatures, presents an additional hurdle due to the lack of accessible datasets, rendering sentiment analysis aformidable undertaking. The limited availability of resources has fueled increased interest among researchers,prompting a deeper exploration into Urdu sentiment analysis. This research is dedicated to Urdu languagesentiment analysis, employing sophisticated deep learning models on an extensive dataset categorized into fivelabels: Positive, Negative, Neutral, Mixed, and Ambiguous. The primary objective is to discern sentiments andemotions within the Urdu language, despite the absence of well-curated datasets. To tackle this challenge, theinitial step involves the creation of a comprehensive Urdu dataset by aggregating data from various sources such asnewspapers, articles, and socialmedia comments. Subsequent to this data collection, a thorough process of cleaningand preprocessing is implemented to ensure the quality of the data. The study leverages two well-known deeplearningmodels, namely Convolutional Neural Networks (CNN) and Recurrent Neural Networks (RNN), for bothtraining and evaluating sentiment analysis performance. Additionally, the study explores hyperparameter tuning tooptimize the models’ efficacy. Evaluation metrics such as precision, recall, and the F1-score are employed to assessthe effectiv

关键词： Urdu sentiment analysis convolutional neural networks recurrent neural network deep learning natural language processing neural networks

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A novel fractional case study of nonlinear dynamics via analytical approach

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 276-290页

作者： Hassan khan Adnan khan Rasool Shah Dumitru Baleanu Department of Mathematics Abdul Wali khan UniversityMardan 23200Pakistan Department of Mathematics Faculty of Arts and SciencesCankaya UniversityAnkara 06530Turkey Institute of Space Sciences Magurele-BucharestRomania

The present work describes the fractional view analysis of Newell-Whitehead-Segal equations,using an innovative *** work is carried with the help of the Caputo operator of fractional *** analytical solutions of some numerical examples are presented to confirm the reliability of the proposed *** derived results are very consistent with the actual solutions to the problems.A graphical representation has been done for the solution of the problems at various fractional-order ***,the solution in series form has the desired rate of convergence and provides the closed-form *** is noted that the procedure can be modified in other directions for fractional order problems.

关键词： Homotopy Perturbation method Shehu transform Newell-Whitehead-Segel Equation Caputo operator

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Electronic and thermoelectric properties of YbMg_(2)X_(2)(X=P,As,Sb,Bi)zintl compounds by first-principles method

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Journal of Rare Earths 2024年第1期42卷 147-154,I0006页

作者： Sajid khan Dil Faraz khan R.Neffati Tariq Usman Muhammad Waqar Ahsraf Shamim khan Saeed Ullah Jan G.Murtaza Department of Physics University of Science&Technology BannuBannu28100Pakistan Department of Physics Faculty of ScienceKing Khalid UniversityP.O.Box 9004AbhaSaudi Arabia Laboratoire de Physique de La Matiere Condensee Departement de PhysiqueFaculte des Sciences de TunisUniversite Tunis El ManarCampus Universitaire1060TunisTunisia Department of Physics Shaoxing UniversityShaoxing312000China Department of Mathematics&Natural Sciences Prince Mohammad Bin Fahd UniversityAlkhobar31952Saudi Arabia Materials Modeling Lab Department of PhysicsIslamia College Peshawar25120KhyberPakhtunkhwaPakistan

In this work the structural,electronic and thermoelectric properties of YbMg_(2)X_(2)(X=P,As,Sb,Bi)zintl compounds were investigated comprehensively using first principles *** electronic properties were studied using PBE GGA,TB-mBJ and hybrid(YS-PBE0)*** the structural parameters of optimized structures are in harmonious agreement to the available *** band structure study illustrates that the titled materials manifest metallic and semi metallic nature using PBE and TB-mBJ potentials while they show wide band gap semiconducting behavior by following hybrid(YS-PBE0)*** density of states(TDOS)and partial density of states(PDOS)were also calculated to glimpse the contribution of orbitals of atoms in the formation of *** properties were studied by using BoltzTraP2 code employed to *** get enormous values of Seebeck coefficient(S),power factor(PF)and thermoelectric figure of merit(ZT)for all the samples YbMg_(2)X_(2)(X=P,As,Sb,Bi),Moreover,the overwhelming transport properties for the titled compounds indicate the optimum level of carriers’concentration which pinpoints these materials to be better thermoelectrics in the 1-2-2 zintl family.

关键词： Zintl compounds Hybrid functional Band structure Thermoelectrics Rare earths

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Performance of Text-Independent Automatic Speaker Recognition on a Multicore System

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Tsinghua Science and Technology 2024年第2期29卷 447-456页

作者： Rand Kouatly Talha Ali khan Faculty of Tech and Software Engineering University of Europe for Applied SciencesPotsdam 14469Germany

This paper studies a high-speed text-independent Automatic Speaker Recognition(ASR)algorithm based on a multicore system's Gaussian Mixture Model(GMM).The high speech is achieved using parallel implementation of the feature's extraction and aggregation methods during training and testing *** memory parallel programming techniques using both OpenMP and PThreads libraries are developed to accelerate the code and improve the performance of the ASR *** experimental results show speed-up improvements of around 3.2 on a personal laptop with Intel i5-6300HQ(2.3 GHz,four cores without hyper-threading,and 8 GB of RAM).In addition,a remarkable 100%speaker recognition accuracy is achieved.

关键词： Automatic Speaker Recognition(ASR) Gaussian Mixture Model(GMM) shared memory parallel programming PThreads OpenMP

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