检索结果-南通市图书馆

Effect of Lateritic Stone Aggregate and Coconut Husk Fiber on the Properties of Concrete

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Civil Engineering 2024年第2期14卷 240-257页

作者： Edmund Borbi Humphrey Danso emmanuel Appiah-Kubi Department of Construction Technology and Management Education Akenten Appiah-Menka University of Skills Training and Entrepreneurial Development Kumasi Ghana Department of Architecture and Civil Engineering Akenten Appiah-Menka University of Skills Training and Entrepreneurial Development Kumasi Ghana

Natural stone aggregate forms the bulk volume of concrete and has contributed to the increased cost of concrete production. This has led to the search for alternate aggregates such as lateritic stone for concrete production. This paper investigates the engineering properties of concrete produced with lateritic aggregate (LA) as the coarse aggregate replacement and coconut husk fibre (CHF) as reinforcement. Natural stone aggregate was replaced by LA at 0%, 10%, 20%, 30%, 40%, and 50%, with 0.25% constant CHF by weight. A mix proportion of 1:1.5:3 with a water-cement ratio of 0.6 was used for producing concrete. A total of 162 specimens (90 cubes and 72 beams) were prepared and tested at the 7, 14, 21, and 28 days of curing. The highest compressive strength was 43.36 N/mm2 (10% LA replacement) as compared to the control of 41.51 N/mm2. The 10% LA replacement obtained the highest flexural strength of 5.35 N/mm2 as compared with the 5.29 N/mm2 for the control. The water absorption of the concrete increased from 2.8% (control) to 3.57% (50% replacement LA). Scanning electron microscopy (SEM) revealed micro gaps between CHF and LA concrete. The study, therefore, concludes that the use of LA and CHF positively influenced the strength properties of concrete. 10% LA replacement of coarse aggregate and 0.25% CHF is recommended to practitioners for use.

关键词： Concrete Coarse Aggregate Compressive Strength Flexural Strength Natural Stone Aggregate SEM

Antimicrobial Activities of Extracts of Macrosphyra longistyla against Gram-Positive Oral Biofilm-Formers from School Children in Southwestern Nigeria and Toxicity Studies Using Brine Shrimps

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Microbiology 2024年第3期14卷 163-174页

作者： Chukwuemeka emmanuel Nwankwo Onikepe Folarin Adeleke Osho Department of Biological Sciences Faculty of Natural Sciences Redeemer’s University Ede Nigeria African Centre of Excellence for Genomics of Infectious Diseases (ACEGID) Redeemer’s University Ede Nigeria

The world will benefit from more effective antimicrobial agents against oral conditions arising from the actions of biofilm forming bacteria. Also, information is lacking on the oral biofilm-forming bacterial diversity in Southwestern Nigeria. In this study, we isolate and characterize oral biofilm producing bacteria in the oral cavities of schoolchildren in Southwestern Nigeria. We also investigate the antimicrobial properties of Macrosphyra longistyla extracts against the biofilm-formers and the toxicity of potent extracts. Samples were obtained from 109 schoolchildren aged 4 - 14 years from Lagos, Oyo and Osun States. Agar well diffusion technique was used in the antimicrobial susceptibility testing. Toxicity testing was done using brine shrimps (Artemia salina). Biofilm-formers in this study are Klebsiella sp., Streptococcus sp., Staphylococcus sp., and Micrococcus sp. Ethanol leaf extracts had the highest activity against all biofilm-producing bacteria. Ethanol stem bark extract, which elicited activity against Klebsiella only, was found to be less toxic than the ethanol leaf extract. Staphylococcus showed >10 mm susceptibility to the ethanol and aqueous extracts of Macrosphyra longistyla. Streptococcus and Micrococcus were susceptible to the antimicrobial actions of the ethanolic leaf extracts. Although the ethanol extracts of the leaves had lower minimum inhibitory concentrations than the ethanol extracts of the stem bark, toxicity studies showed ethanol extracts of the stem-bark to be more toxic than the ethanol extracts of the leaves. In conclusion, ethanolic extracts of Macrosphyra longistyla show potential as sources of antimicrobials against gram-positive, oral biofilm-forming bacteria.

关键词： Biofilms Plant Extracts Toxicity Bacteria Susceptibility Antimicrobial

Persicaria lanigera (Polygonaceae) leaf extract exhibits antiulcerogenic and antiproliferative activities against acetic acid-induced ulcerative colitis and cotton pellet-induced granuloma tissue in rats

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Biomedicine 2024年第7期14卷 269-278页

作者： Meshack Antwi-Adjei Ernest Obese emmanuel Awintiig Adakudugu Benjamin Aboagye Daniel Anokwah Akua Afriyie Karikari Roberta Antwi-Adjei Elvis Ofori Ameyaw Department of Pharmacology School of Medical SciencesUniversity of Cape CoastCape CoastGhana Department of Pharmacotherapeutics and Pharmacy Practice School of Pharmacy and Pharmaceutical SciencesUniversity of Cape CoastCape CoastGhana Department of Forensic Sciences School of Biological SciencesUniversity of Cape CoastCape CoastGhana Department of Pharmacognosy and Herbal Medicine School of Pharmacy and Pharmaceutical SciencesUniversity of Cape CoastCape CoastGhana Department of Biomedical Sciences School of Allied Health SciencesCollege of Agriculture and Natural SciencesUniversity of Cape CoastCape CoastGhana

Objective:To assess the effect of leaf extract of Persicaria lanigera on cotton pellet-induced granuloma tissue formation and acetic acid-induced ulcerative ***:Rats were randomly divided into six groups:normal control,negative control,positive control(dexamethasone or sulfasalazine)as well as Persicaria lanigera(100-600 mg/kg)-treated *** effects of the extracts on body weight,antioxidant,and hematological parameters,as well as mast cell proliferation,were *** addition,a histological evaluation was ***:Persicaria lanigera extract significantly decreased the mean exudate amount and suppressed granuloma tissue formation in a concentration-dependent manner in rats(P<0.05).Additionally,the extract significantly increased body weight,improved hematological profile,reduced the disease activity index score and malondialdehyde level,as well as enhanced catalase and superoxide dismutase activities(P<0.05).Histological evaluation showed Persicaria lanigera extract alleviated acetic acid-induced colonic damages,as evidenced by decreased cell necrosis,edema,and inflammatory cell ***:Persicaria lanigera extract possesses antiproliferative,antioxidative,and anti-colitis ***,its underlying mechanisms of action need further investigation.

关键词： Colitis Persicaria lanigera Antioxidant Cotton pellets Mast cells Granuloma tissue formation

Oral Hygiene in the Presence of Orthodontic Therapy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Biosciences and Medicines 2024年第2期12卷 98-110页

作者： emmanuel John Aryeetey Hicham Benyahia Fatima Zaoui Faculty of Dental Medicine Mohammed University in Rabat Rabat Morocco

Orthodontic treatment offers great advantages in improving facial and smile aesthetics, self-confidence and the function of the stomatognathic apparatus. The pursuit of these advantages makes use of orthodontic appliances that could be fixed or removable. However, it’s worth stating that these appliances interfere with tooth brushing, making it more difficult to brush teeth effectively. Orthodontics appliances therefore promote the accumulation of dental plaque, which results in both quantitative and qualitative changes in the oral microbiota, hence, exposing patients to several adverse effects such as White spot lesions, dental caries, periodontal pathologies and halitosis. For this reason, oral assessment of patients before, during and after treatment is necessary as well as oral hygiene instructions and motivation. Orthodontists therefore, should educate patients on oral and periodontal hygiene in order to control dental and periodontal complications. Prescriptions of plaque control materials adapted to each patient are done in order to optimize the final result and minimize unwanted complications.

关键词： Orthodontic Treatment Oral Microbiome Oral Hygiene Periodontitis Gingivitis Orthodontic Fixed Appliances Orthodontic Removable Appliances White Spot Lesions (WSL)

Multi-site Passivation of ZnO Metal Oxides via Biomolecules for Efficient and Highly Stable Organic Solar Cells

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2024年第14期42卷 1582-1592页

作者： Irfan Ismail Maria Khalil Xiaomei Gao Xingze Chen Muhammad Jawad Rong Huang Zhiyun Li emmanuel Acheampong Tsiwah Wei-shi Li Qun Luo Chang-Qi Ma i-Lab&Printable Electronics Research Center Suzhou Institute of Nano-Tech and Nano-Bionics(SINANO)Chinese Academy of Sciences(CAS)SuzhouJiangsu215123 China University of Chinese Academy of Sciences(UCAS) Beijing100040 China School of Nano-Tech and Nano-Bionics University of Science and Technology of China(USTC)HefeiAnhui230027 China Shanghai Institute of Organic Chemistry(SIOC) Chinese Academy of Sciences(CAS)Shanghai200032 China Vacuum Interconnected Nanotech Workstation(Nano-X) SuzhouJiangsu215123 China

ZnO nanoparticles(nps)among metal oxide(MOs)are proven to be essential electron transporting layers(ETLs)applied in organic solar cells(OSCs).However,intrinsic defects,interfacial charge recombination,and catalytic behavior towards the active layer restrict the applications of ZnO nps for efficient and long-term stable *** commonly available biomolecule cytidine 5'-monophosphate(CMP-OH)with phosphonic acid,its salt cytidine 5'-monophosphate disodium salt(CMP-ONa)with a phosphate group as an anchoring group and conjugated terminal functional in both analogous molecules provide carrier transfer bridge at bottom interface of the active *** theoretical investigations and characterizations have discovered the multi-site coordination of CMP-OH towards acceptor molecules and ZnO *** dual-side alignment of CMP analogous molecules hinders interfacial charge recombination and enhances charge transfer potential at ***,PM6:L8-BO-based OSCs with modified ETL obtain 18.13%efficiency,12%higher than that of unmodified *** higher efficiency,CMP-OH-based OSC devices illustrate remarkably improved thermal stability for 500 h at 85℃with 72%of initial PCE and operation stability for 2000 h with 90.1%of initial *** work reveals the passivation mechanism of multi-anchoring groups towards MOs and single-functional groups towards the active layer to optimize the interface for efficient and highly stable OSCs.

关键词： Organic solar cells Nanoparticles Nucleotides Interfacial interactions Surface chemistry Multi-site passivation

检查清单和错误报告系统在提高患者安全和减少医疗差错方面的有效性:叙述性回顾

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Nursing Sciences 2024年第3期11卷 387-398页

作者： emmanuel Aoudi Chance Dia Florence Innocent Sardi Abdoul VID Specialized University BergenNorway Universite de Bertoua Cameroon Univerity of Ngaoundere Cameroon

目的探讨检查清单和错误报告系统对医院患者安全和医疗错误的影响。方法系统检索2013一2023年的学术数据库,对符合纳入标准的同行评议研究进行严谨的方法学评估。该综述强调了支持核对表在减少用药错误、手术并发症和其他不良事件方面... 详细信息

目的探讨检查清单和错误报告系统对医院患者安全和医疗错误的影响。方法系统检索2013一2023年的学术数据库,对符合纳入标准的同行评议研究进行严谨的方法学评估。该综述强调了支持核对表在减少用药错误、手术并发症和其他不良事件方面的有效性证据。错误报告系统提高了透明度,鼓励专业人员报告事件并识别系统漏洞。结果检查表和错误报告系统相互关联,在检查表的实施中强调跨专业合作。文章中使用的不同方法和潜在的发表偏倚可能产生局限性;此外,语言限制可能会排除有价值的非英语研究。虽然积极的影响是显而易见的,但成功取决于组织文化和资源。结论通过查阅相关文献,强调干预措施的重要性,并呼吁进一步研究检查清单和错误报告系统在不同医疗保健和文化背景下的有效性,有助于提高患者安全知识。了解这些动态变化对于医疗保健提供者优化患者安全至关重要。

关键词：患者安全医疗错误检查表错误报告系统健康状况

Unintended Pregnancy Determinants among Antenatal Clinic Attendees: A University of Port Harcourt Teaching Hospital Experience

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Biosciences and Medicines 2024年第4期12卷 229-245页

作者： Ijeoma Chioma Oppah Terhemen Kasso emmanuel Okwudili Oranu Department of Obstetrics and Gynaecology University of Port Harcourt Teaching Hospital Port Harcourt Nigeria Department of Obstetrics and Gynaecology University of Port Harcourt Port Harcourt Nigeria

An unintended pregnancy is a pregnancy that is either mistimed or unplanned. The objectives of this study were to determine the prevalence of unintended pregnancy as well as to document the determinant factors among pregnant women attending antenatal clinics at the University of Port Harcourt Teaching Hospital (UPTH), Port Harcourt, Rivers State, Nigeria. It was a descriptive, cross-sectional study of 215 women attending the antenatal clinic of UPTH from July to August 2022. Information on socio-demographic characteristics, reproductive history, desirability of the current pregnancy at the time of conception, knowledge and use of contraceptive methods were collected using a pretested questionnaire and analyzed using SPSS version 26.0. Chi-square test was used for test of associations with the level of significance set at P < 0.05. The prevalence rate of unintended pregnancy from the study was 16.28% (≈16%). The contraceptive awareness was very high (209, 97.21%), however, 101 (46.98%) participants had never used any form of contraceptives. Univariate analysis using Chi-square test showed a statistically significant association between age and unintended pregnancy (P = 0.042), level of education and unwanted pregnancy (P = 0.033) as well as parity and unintended pregnancy (P = 0.019). The prevalence of unintended pregnancy among women attending antenatal clinics was high, possibly due to low contraceptive usage. More efforts should be geared towards ensuring access to comprehensive contraceptive care and contraceptive methods, this will enhance uptake and reduce the rate of unintended pregnancy.

关键词： Unintended Pregnancy Determinants Prevalence Antenatal Attendees

Influence of Production Factors on the Physico-Chemical Characteristics of Fermented Cassava Dough and Sensory Evaluation of Attieke

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Food and Nutrition Sciences 2024年第5期15卷 361-376页

作者： Weiléko Hélène Dougba Djedjro Clément Akmel emmanuel Aya Diane Boudouin Dibi Nogbou emmanuel Assidjo Laboratory of Industrial Processes for Environmental Synthesis and New Energies Institut National Polytechnique F&#233lix Yamoussoukro C&#244te d&#8217Ivoire Department of Agro-Food and Food Industries UFR Agriculture Fisheries Resources and Agro-Industry University of San-Pedro San-Pedro C&#244te d&#8217Ivoire

Attieke is an Ivorian semolina which obtained by fermenting, pressing and steaming cassava dough. Attieke production remains a traditional activity carried out by less literate women. However, perceived differences in measurable factors and attieke qualities require an investigation of their influence on the characteristics of the pressed dough and attieke. The aim of this study is to improve the quality of the dough in relation to that of the attieke produced. The experiment was carried out on 4 production factors, namely the type of boiled or braised ferment, the incorporation rate of the ferment between 8 and 10%, the addition of oil from 0.1 to 1% and the fermentation time from 12 to 15 hours applied to the Improved African Cassava (IAC) variety. A complete experiment design of 16 samples of fermented dough and attieke was employed. These samples underwent physic-chemical analyses for the fermented dough and sensory evaluation for the attieke. It was found that, except for titratable acidity, reducing sugar content and ash content, the physico-chemical characteristics of the dough of IAC variety were significantly influenced by all production factors and their interaction. Fermentation time significantly influences 60% of the physico-chemical characteristics of the fermented dough. The type of ferment, the oil addition and the ferment rate have a significant influence at 40% of these characteristics. At the sensory level, color, acidity and grain binding with an explained variance of 34.60% were essential for the appreciation of the attieke samples. Thus, these production factors could be considered for the improvement of the fermented dough and attieke production process.

关键词： Influence Production Fermented Dough Attieke

A Pragmatic Template for Quadcopter Development

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Aerospace Science and Technology 2024年第2期9卷 61-74页

作者： Iyenagbe Benjamin Ugheoke Abdulhakeem Hassan Nurudeen Olusola Ayodeji Abiire Aniedi Okon Edem emmanuel Adedayo Towoju emmanuel Ogo Onche Department of Mechanical Engineering Faculty of Engineering University of Abuja Abuja Nigeria

This article presents a pragmatic quadcopter development template for parcel delivery in Nigeria. The quadcopter is equipped with a camera, parcel pouch and wireless telecommunication to capture live events and send them back to the control station for real-time delivery feedback. The study also discusses the design methodology adopted as a conceptual design approach vital to product development, it encompasses information gathering and identifying the problem, creating the solutions systematically and eventually evaluating and developing a concept for the drone and its attributes and presenting clear results for design calculations.

关键词： Drone Unmanned Aeriel Vehicles Quadcopter Drone Development Flight