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Chemically Modified Uridine Molecules Incorporating Acyl Residues to Enhance Antibacterial and Cytotoxic Activities

International Journal of Organic Chemistry 2015年第4期5卷 232-245页

作者： Sark.r M. A. k.wsar Hamida A. Ara Sheik. Aftab Uddin mohammed k. hossain Shagir A. Chowdhury Abul F. M. Sanaullah Mohammad A. Manchur Imtiaj Hasan Yuk.k. Ogawa Yuk. Fujii Yasuhiro k.ide Yasuhiro Ozek. Laboratory of Carbohydrate and Protein Chemistry Department of Chemistry Faculty of Science University of Chittagong Chittagong Bangladesh The Institute of Marine Science Faculty of Science University of Chittagong Chittagong Bangladesh Department of Pharmacy Faculty of Biological Science University of Chittagong Chittagong Bangladesh Department of Microbiology Faculty of Biological Science University of Chittagong Chittagong Bangladesh Laboratory of Glycobiology and Marine Biochemistry Department of Life and Environmental System Science Graduate School of NanoBio Sciences Yokohama City University Yokohama Japan Divisions of Microbiology Graduate School of Pharmaceutical Science Nagasaki International University Nagasaki Japan

A new N-acetylsulfanilylation series of uridine have been synthesized in good yield using direct acylation method and afforded the 5’-O-N-acetylsulfanilyluridine. In order to obtain newer products, the 5’-O-N-acetylsulfanilyluridine derivative was further transformed to a series of 2’,3’-di-O-acyl derivatives containing a wide variety of functionalities in a single molecular framework. The chemical structures of the newly synthesized compounds were confirmed on the basis of their FTIR, 1H-NMR spectroscopy, physicochemical properties and elemental analysis. All the synthesized uridine derivatives were tested for their in vitro antibacterial activity against six human pathogenic bacterial strains and for comparison standard antibiotic Ampicillin was also determined. The study revealed that the selectively acylated deriva-tives 5’-O-N-acetylsulfanilyl-2’,3’-di-O-lauroyluridine and 5’-O-N-acetylsulfanilyl-2’,3’-di-O-pivaloyluridine showed highest inhibition against Staphylococcus aureus and Bacillus cereus, respectively. We also observed that the introduction of hexanoyl, decanoyl, lauroyl, myristoyl and pivaloyl groups, the antibacterial functionality of the compound uridine increases. Another noteworthy observation was that the uridine derivatives were found comparatively more effective against Gram-positive microorganisms than those of Gram-negative microorganisms. In addition, the test chemicals were also tested for cyto-toxicity by brine shrimp lethality bioassay and compounds showed different rate mortality with different concentrations.

关键词： Uridine Synthesis Structure Spectroscopy Antibacterial Cytotoxicity

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The use of grass as an environmentally friendly additive in water-based drilling fluids

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Petroleum Science 2016年第2期13卷 292-303页

作者： M.Enamul hossain mohammed Wajheeuddin Department of Petroleum Engineering College of Petroleum Engineering and GeosciencesKing Fahd University of Petroleum & Minerals(KFUPM)

Excellent drilling fluid techniques are one of the significant guaranteed measures to insure safety, qual- ity, efficiency, and speediness of drilling operations. Dril- ling fluids are generally discarded after the completion of drilling operations and become waste, which can have a large negative impact on the environment. Drilling mate- rials and additives together with drill cuttings, oil, and water constitute waste drilling fluids, which ultimately are dumped onto soil, surface water, groundwater, and air. Environmental pollution is found to be a serious threat while drilling complex wells or high-temperature deep wells as these types of wells involve the use of oil-based drilling fluid systems and high-performance water-based drilling fluid systems. The preservation of the environment on a global level is now important as various organizations have set up initiatives to drive the usage of toxic chemicals as drilling fluid additives. This paper presents an approach where grass is introduced as a sustainable drilling fluid additive with no environmental problems. Simple water- based drilling fluids were formulated using bentonite, powdered grass, and water to analyze the rheological and filtration characteristics of the new drilling fluid. A particle size distribution test was conducted to determine the par- ticle size of the grass sample by the sieve analysis method. Experiments were conducted on grass samples of 300, 90, and 35 μm to study the characteristics and behavior of the newly developed drilling fluid at room temperature. The results show that grass samples with varying particle sizes and concentrations may improve the viscosity, gel strength, and filtration of the bentonite drilling fluid. These obser- vations recommend the use of grass as a rheological modifier, filtration control agent, and pH control agent to substitute toxic materials from drilling fluids.

关键词： Rheology - Filtration - Filter cak. Apparentviscosity Plastic viscosity Gel strength

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Governance of forest conservation and co-benefits for Bangladesh under changing climate

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Journal of Forestry Research 2014年第1期25卷 29-36页

作者： Ronju Ahammad mohammed k.mal hossain Panna Husnain Community Based Adaptation to Climate Change through Coastal Afforestation Project Bhan Bhaban Agargaon Dhaka-1207 Bangladesh. Institute of Forestry & Environmental Sciences University of Chittagong Bangladesh. Urban Planner Solaiman Nagar Minara Maszid Road Khulna Bangladesh.

We focused on k.y aspects of forest governance for biodiver- sity conservation in implementing new climate change policies. The national forest institutions must be adaptive to identify the existing pitfalls of prior conservation policies to tak. advantage of new climate change policies. Strengthening roles and technical capacity of national institutions for systematic biodiversity monitoring and carbon stock.assessment is required in developing and least developed countries. Community participation needs careful analysis to ensure equitable ac- cess of particular social groups to local decision-mak.ng processes and to sustain optional livelihoods. The livelihood options around forest reserves or protected areas must be tak.n into account to enhance forest-based adaptation.

关键词： REDD+ (Reducing Emissions from Deforestation and Forest Degradation in Developing Countries) conservation institution livelihood protected areas

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Microalgae cultivation in photobioreactors:sustainable solutions for a greener future

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Green Chemical Engineering 2024年第4期5卷 418-439页

作者： Shaik. Abdur Razzak.k.airul Bahar k.M.Oajedul Islam Abdul k.aleel Haniffa mohammed Omar Faruque S.M.Zak.r hossain Mohammad M.hossain Chemical Engineering Department King Fahd University of Petroleum and MineralsDhahran31261Saudi Arabia Center for Refining and Advanced Chemicals King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Department of Chemical Engineering University of BahrainZallaqBahrain

Microalgae cultivation in photobioreactors(PBRs)has emerged as a promising and sustainable approach to address various environmental and energy challenges,offering a multitude of benefits across diverse *** developments in microalgae cultivation in photobioreactors have contributed substantially to the development and optimization of sustainable *** review presents a comprehensive analysis of recent innovations and break.hroughs in the field of microalgae cultivation,with a specific focus on their application in photobioreactors,aimed at paving the way for a greener *** study in-depth examines the advantages of microalgae cultivation in photobioreactors,concentrating on its effectiveness in wastewater treatment,CO_(2)bioremediation,and the production of biofuels and high-value *** review evaluates the effects of light,solar irradiation,temperature,nitrogen and phosphorus concentrations in culture media,CO_(2)concentrations,and pH on microalgae growth performance,including specific growth and biomass *** study also examines open systems lik. unstirred ponds,raceway ponds,and circular ponds and closed systems lik. horizontal tubular,vertical bubble-column,airlift,flat panel,and plastic-bag photobioreactors,comparing their pros and *** optimize microalgae cultivation,k.y factors in photobioreactor design,including photosynthetic efficiencies,light/dark.L/D)cycles,CO_(2)concentrations,mass transfer,hydrodynamics behavior,and p H,are extensively *** addition,the review outlines recent developments in large-scale photobioreactors and highlights the challenges and opportunities associated with photobioreactor scale-up and design parameter optimization,including genetic engineering and economic *** article is a vital resource for researchers,engineers,and industry professionals seek.ng sustainable bioprocesses and the application of microalgae-based technologies.

关键词： Microalgae biomass CO_(2)biofixation Wastewater treatment Biofuel Photobioreactors

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The effects of teak.monoculture on forest soils: a case study in Bangladesh

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Journal of Forestry Research 2018年第4期29卷 1100-1109页

作者： Md.Abdullah Al Mahmud Mohammad Mahfuzur Rahman mohammed k.mal hossain Institute of Forestry and Environmental Sciences University of Chittagong

Teak.plantations date back.to 1871 in Bangladesh. This study was designed to assess how teak.monoculture has impacted the soil properties in Bangladesh. Multiple linear regression and correlation matrices were estimated to evaluate these impacts. The means of soil physicochemical properties were compared across various attributes of the plantations. Older plantations accumulated more organic carbon in the soils than the younger plantations. Excessive removal of litter from the forest floor resulted in reduced levels of N, P, k. and other nutrients in the soils. Since bulk.density was continuously decreasing deeper into the soil, the penetration of mineral nutrients into the soil was low. Furthermore, moisture content in the topsoil was significantly lower than that in the bottom layers due to the exposed and dry condition of the forest floor under teak.plantations. For improving depleted teak.plantation soils, teak.could be planted with other tree species rather than just in monocultures. In addition, the forest floor could be enriched with leguminous herbs and shrubs to improve soil health in these plantations.

关键词： CHTs Monoculture. Organic carbon Soilnutrients Teak.plantation

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Comparative phytochemical,thin layer chromatographic profiling and antioxidant activity of extracts from some Indian herbal drugs

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Journal of Bioresources and Bioproducts 2022年第2期7卷 46-52页

作者： Md Sohail Ak.tar Mohamed Rafiullah Wegdan Aly Shehata Amzad hossain mohammed Ali School of Pharmacy College of Pharmacy and NursingUniversity of NizwaNizwaOman Phytochemistry Research Laboratory Department of Pharmacognosy and PhytochemistryFaculty of PharmacyJamia HamdardNew DelhiIndia Strategic Center for Diabetes Research College of MedicineKing Saud UniversityRiyadhSaudi Arabia

Natural antioxidants play a significant role to prevent cell break.ng and regenerate *** plants native to India named dwarf morning-glory(Evolvulus alsinoides),Indian banyan(Ficus bengalensis)and chicory(Chicorium intybus)are used as medicine in India traditionally to treat *** aim of this study is to evaluate and compare the antioxidant activity as well as to compare phytochemical profiles of the aqueous extracts of the selected three *** dried plant powder was extracted with ethanol individually by using the Soxhlet method for eight hours and the solvent was evaporated under reduced ***,the air-dried powder was ex-tracted with water,and the water was *** thin layer chromatography(TLC)profile of the extracts was determined by using TLC densitometer and the antioxidant activity was deter-mined by the conventional 2,2-diphenyl-1-picrylhydrazyl(DPPH)*** TLC profile shows that there are no similarities of retention factor(R f)values among the plant extracts which means all three plants contain different chemical *** antioxidant activities of the aqueous extracts at different concentrations show different antioxidant *** inhibition is dose dependent,as doses are increasing then percentage inhibition is also increasing for all three plant *** the selected plants,the highest activity was found in *** and the lowest was in *** order of the antioxidant activity among the selected plants was ***<***<*** on the TLC profile and antioxidant activities,the highest activity of the selected plant species was evaluated.

关键词： Indian drug Thin layer chromatography(TLC)profile Plant extract Antioxidant activity

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Vegetative propagation of Litsea monopetala, a wild tropical medicinal plant: Effects of indole-3-butyric acid (IBA) on stem cuttings

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Journal of Forestry Research 2011年第3期22卷 409-416页

作者： Tarit k.mar Baul Mohammad Mosharraf hossain Mohammad Mezbahuddin mohammed Mohiuddin School of Environment Natural Resources and Geography Bangor University Bryn Eithin Room K35 St. Mary's Site Bangor LL57 1DZ UK. Institute of Forestry and Environmental Sciences University of Chittagong Chittagong 4331 Bangladesh Research Fellow Graduate School of Engineering Osaka University Suita Osaka 565-0871 Japan Department of Renewable Resources University of Alberta Canada Professor Institute of Forestry and Environmental Sciences University of Chittagong Chittagong 4331 Bangladesh

In this study we investigated the rooting ability and the growth performance of juvenile single-node leafy stem cuttings of Litsea monopetala （Roxb） Pers. collected from two mature mother trees preserved in the hill forest of Chittagong district, Bangladesh. The rooting ability of cuttings was studied under 0%, 0.1%, 0.2% and 0.4% indole-3-butyric acid （IBA） treatments. Significantly better rooting response （p ≤ 0.05） was observed with 0.1% IBA compared to control （0% IBA）. The mean number of roots and the length of the longest root of cuttings in different treatments showed no significant difference （p≤0.05）. After transfer into polythene bags from non-mist propagator, rooted cuttings treated with 0%, 0.1% and 0.2% IBA demonstrated the highest （100 ± 0.00%） survival capacity. The mean number of shoots developed in cuttings in the polythene bags in first three week. varied significantly （p≤0.05） among the treatments. Effects of three fertilizer treatments, viz. T0 （no fertilizer）, T1 （10g Urea, 20g TSP, 10g MOP dissolved in 1 L water） and T2 （10g Urea, 20g TSP, 10g MOP dissolved in 2 L water） on initial growth ofsteck.ings were also measured over a 90-days period. The increment of leaf area of steck.ings was significantly higher （p≤0.05） under T0 compared with that under T1 and T2 while the increment of stem length, collar diameter and root biomass varied insignificantly among different fertilizer treatments. The results suggest that rooting juvenile single-node leafy stem cuttings could be an effective mean of regenerating L. monopetala. The application of 0.1% IBA concentration is recommended for rooting of juvenile leafy stem cuttings and application of fertilizer appeared unnecessary for the subsequent growth of steck.ings in polythene bags.

关键词： IBA Litsea monopetala non-mist propagator rooting stem cutting

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Effect of Multi-Step Tempering on Retained Austenite and Mechanical Properties of Low Alloy Steel

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Journal of Iron and Steel Research International 2011年第12期18卷 49-56页

作者： Hamid Reza Bak.sheshi-Rad Ahmad Monshi hossain Monajatizadeh Mohd Hasbullah Idris mohammed Rafiq Abdul k.dir Hassan Jafari Materials Engineering Department Islamic Azad University Materials Engineering Department Faculty of Mechanical EngineeringUniversity Technology Malaysia Materials Engineering Department Faculty of Mechanical EngineeringShahid Rajaee Teacher Training University

The effect of multi-step tempering on retained austenite content and mechanical properties of low alloy steel used in the forged cold back.up roll was *** evolutions were characterized by optical microscope,X-ray diffraction,scanning electron microscope and Feritscope,while the mechanical properties were determined by hardness and tensile *** results revealed that the content of retained austenite decreased by about 2% after multi-step ***,the content of retained austenite increased from 3.6% to 5.1% by increasing multi-step tempering *** hardness and tensile strength increased as the austenitization temperature changed from 800 to 920 ℃,while above 920 ℃,hardness and tensile strength *** addition,the maximum values of hardness,ultimate and yield strength were obtained via triple tempering at 520 ℃,while beyond 520 ℃,the hardness,ultimate and yield strength decreased sharply.

关键词： cold back.up roll retained austenite mechanical property austenite grain size

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Forecasting Mental Stress Using Machine Learning Algorithms

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Computers, Materials & Continua 2022年第9期72卷 4945-4966页

作者： Elias hossain Abdulwahab Alazeb Naif Almudawi Sultan Almak.i mohammed Alshehri M.Gazi Golam Faruque Wahidur Rahman Department of Software Engineering Daffodil UniversityDhakaBangladesh Collage of Computer Science and Information System University of NajranNajranSaudi Arabia Department of Computer Science and Engineering Khwaja Yunus Ali UniversitySirajganj 6751Bangladesh

Depression is a crippling affliction and affects millions of individuals around the *** general,the physicians screen patients for mental health disorders on a regular basis and treat patients in collaboration with psychologists and other mental health experts,which results in lower costs and improved patient ***,this strategy can necessitate a lot of buy-in from a large number of people,as well as additional training and logistical ***,utilizing the machine learning algorithms,patients with depression based on information generally present in a medical file were analyzed and *** methodology of this proposed study is divided into six parts:Proposed Research Architecture(PRA),Data Pre-processing Approach(DPA),Research Hypothesis Testing(RHT),Concentrated Algorithm Pipeline(CAP),Loss Optimization Stratagem(LOS),and Model Deployment Architecture(MDA).The Null Hypothesis and Alternative Hypothesis are applied to test the *** addition,Ensemble Learning Approach(ELA)and Frequent Model Retraining(FMR)have been utilized for optimizing the loss ***,the Features Importance Interpretation is also delineated in this *** forecasts could help individuals connect with expert mental health specialists more quick.y and *** to the findings,71%of people with depression and 80%of those who do not have depression can be appropriately *** study obtained 91%and 92%accuracy through the Random Forest(RF)and Extra Tree *** after applying the Receiver operating characteristic(ROC)curve,79%accuracy was found on top of RF,81%found on Extra Tree,and 82%recorded for the eXtreme Gradient Boosting(XGBoost)***,several factors are identified in terms of predicting depression through statistical data *** the additional effort is needed to develop a more accurate model,this model can be adjustable in the healthcare sector for diagnosing depression.

关键词： Depression analysis mental health machine learning model deployment XGBoost ROC-AUC

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Composition analysis and antimicrobial activity of essential oil from leaves of Laurus nobilis grown in Oman

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Journal of Bioresources and Bioproducts 2022年第4期7卷 328-334页

作者： Siham Saleh Al-Abri Sadri Abdullah Said Salem Said Al Touby mohammed Amzad hossain Jamal Nasser Al-Sabahi School of Pharmacy College of Pharmacy and NursingUniversity of NizwaPB 33PO 616NizwaNizwa 616Oman School of Nursing College of Pharmacy and NursingUniversity of NizwaNizwa 616Oman Central Instrument Laboratory College of Agriculture and Marine SciencesSultan Qaboos UniversityMuscat 123Oman

Traditionally,Laurus nobilis is used for the treatment of earaches and sk.n rashes as well as *** most common technique to isolate the oil is hydro-distillation and *** investigation presented in this paper was aimed to unravel the antimicrobial activity and chemical composition of essential oil in the leaves of *** grown in *** essential oil was extracted from the leave of the selected plant species by hydro distillation using Clevenger type *** antimicrobial assay was done by disc diffusion methods against three bac-terial strains,Staphylococcus aureus,Pseudomonas aeruginosa and Escherichia coli,and one fungal strain:Candida *** isolated essential oil was analyzed by gas chromatography-mass spectrometry(GC-MS).The percentage yield of the essential oil was 0.064%(w/w).The essen-tial oil was found actively against the applied bacterial and fungal *** highest activity was found against *** and the lowest was against ***,and the order was ***>***>*** essential oil was also active against the fungus *** range of inhibition zones was 6-14 *** results of GC-MS analysis showed(E)-𝛽-caryophyllene to be the major component about 59.62%.Other major components included𝛼-selinene(14.03%),𝛼-humulene(8.65%),𝛽-selinene(4.99%),and𝛼-pinene(4.98%).In addition,several minor com-ponents were found in the essential oil of *** on the experimental results,it showed that the plant species that grown in Oman were a potential source of therapeutic *** con-clusion,the essential oil and the plant could be used as natural and potential therapeutic agents to treat earaches,sk.n rashes,and rheumatism.

关键词： Laurus nobilis Clevenger apparatus Essential oil Antimicrobial activity Gas chromatography-mass spectrometry(GC-MS)

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