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Evaluation of phytochemical properties and in-vitro antibacterial activity of the aqueous extracts of leaf,seed and root of Abrus precatorius Linn. against Salmonella and Shigella

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Asian Pacific Journal of Tropical Biomedicine 2016年第9期6卷 755-759页

作者： ojo joseph sunda. Shola Kola Babatunde Adeyinka Elizabeth Ajiboye Racheal Majekodunmi Adedayo Mufutau Adeyemi Ajao Busayo Isreal Ajuwon Department of Biosciences and Biotechnology Kwara State University

Objective:To investigate the phytochemical components of Abrus precatorius(***) and the in-vitro susceptibility of Salmonella typhi and Shigella dysenteriae to the aqueous extracts of *** leaf,seed and ***:The leaf,seed and root of *** were collected and homogenized separately after drying at 40℃ for seven days in hot-air *** aqueous extracts of each of the parts were prepared and subjected to phytochemical *** of 400,300,200,100 mg/mL,of each of the extracts were used for broth dilution in minimum inhibitory concentration(MIC) determination against clinical isolates of Salmonella typhi and Shigella dysenteriae,while 50,40,30,20,and 10 mg/mL dilutions were used for the agar diffusion test and 100 mg/mL and 10 mg/mL of gentamycin were used as controls for broth dilution in MIC determination and agar diffusion test,***:Qualitative study reveals that tannin,saponins,alkaloids,flavonoids,terpenoids,steroids and phenols were present in all of the plant *** leaf has the highest quantities of tannin and *** root generally showed the lowest quantity of all the *** pathogens were susceptible to aqueous extracts of the leaf,stem and root of *** at 50 mg/*** concentrations of 40,30 and 20 mg/mL,all the aqueous extracts of *** showed variation in MIC,but produced no minimum bactericide effect upon *** were variations in diameter of zone of inhibition against the organisms at lower ***:These findings suggest that *** is a valuable source of phytochemicals with promising antibacterial *** this bioactivity,*** could be probed further for toxicity,and to obtain some novel antibacterial molecules.

关键词： Abrus precatorius Phytochemicals Antibacterial susceptibility Salmonella Shigella

Resonant-Inductive Wireless Power Transfer for Autonomous Mobile Robots

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Instrumentation 2019年第1期6卷 55-84页

作者： joseph ojo Xianke LIN Haoxiang LANG University of Ontario Institute of Technology Oshawa Ontario LlH 7K4Canada

Due to the increasing commercial interest in autonomy and sustainability,this paper reviews and presents a comprehensive summary of the resonant-inductive power transmission(RPT)technology for autonomous mobile *** outlines historic and recent research activities in wireless power transmission,covering the fundamental operation of microwave,capacitive and inductive power transfer technologies,state-of-the-art developments in RPT for high-power applications,current design and health standards,technological drawbacks,and possible future *** this paper,coupling-enhanced pad designs,adaptive tuning techniques,compensation network designs,and control techniques are *** design issues such as coupling variation,frequency splitting,and bifurcation are *** difference between maximum power transfer and maximum energy efficiency is *** exposure guidelines are summarized from documentations provided by the Institute of Electrical and Electronics Engineers(IEEE)and the International Commission on Non-ionizing Radiation Protection(ICNIRP).Other standards like WPC’s Qi and Airfuel design standards are also ***,the possible trends of the relevant research and development,particularly dynamic charging,are *** intention of this review is to encourage designs that will relieve robot operators of the burden of frequent manual recharging,and to reduce downtime and increase the productivity of autonomous mobile robots in industrial environments.

关键词： Wireless Power Transfer Wireless Charging Resonant coupling Mobile Robots AMRs AGVs

Analysis of Vertical Profiles of Precipitable Liquid Water Content in a Tropical Climate Using Micro Rain Radar

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Journal of Geoscience and Environment Protection 2019年第2期7卷 140-155页

作者： joseph S. ojo Omololu O. Daodu Olalekan L. ojo Department of Physics Federal University of Technology Akure Nigeria Department of Physics Elizade University Ilara-Mokin Nigeria

In this paper, some distinctive features of the vertical profile of precipitable liquid water content (LWC) with considerable respect to rain rates (R) and radar reflectivity (Z) obtained in a tropical location are presented. Assessment of LWC allows applications in the specific area of flight icing severity, aviation safety as well as signals traversing through the atmosphere. The parameters were typically measured using vertically-pointing Micro Rain Radar (MRR) over a period of 2 years (2011-2012) at Akure, a tropical location of Nigeria. The radar scanned at every 10 seconds and integrated over one minute samples to reduce event logging error associated with the instrument. The vertical profile of the LWC typically reveals a prominent seasonal variation. However, majority of the LWC profiles has low LWC, less than 0.1 gm?3 while the maximum observed LWC is about 3.18 gm?3. A strong like hood relation was observed between the melting layer height and the LWC, with the LWC reaches peak at the considerable height of about 4160 m which coincides precisely with the freezing height level (rain height of ~4520 m) of the study location. Good correlation was also observed between the LWC and R in most of the heights considered. The results obtained will assist system engineers to assess the level of absorption, reflection and attenuation of electromagnetic signals as a result of precipitable LWC along the transmitting paths. The novelty of the present work is in the area of linking LWC and Z as against usual relation between Z and R.

关键词： Liquid Water Content Micro Rain Radar Vertical Profile Tropical Climate Radar Reflectivity Factor

N-杂环卡宾催化碳-碳/杂原子键构筑的机理和区域/化学选择性理论研究

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N-杂环卡宾催化碳-碳/杂原子键构筑的机理和区域/化学选择性理论...

作者： ojo joseph Busayo 东北师范大学

学位级别：硕士

N-杂环卡宾(NHC)有机催化已成为现代有机合成中一种强有力的策略。基于NHC的有机催化剂已经开发出许多重要的合成反应,实现了碳-碳和碳-杂原子键的构筑。特别是在化学和区域选择性有机合成领域,NHCs催化剂显示出催化效率高、选择性好、... 详细信息

N-杂环卡宾(NHC)有机催化已成为现代有机合成中一种强有力的策略。基于NHC的有机催化剂已经开发出许多重要的合成反应,实现了碳-碳和碳-杂原子键的构筑。特别是在化学和区域选择性有机合成领域,NHCs催化剂显示出催化效率高、选择性好、环境友好及性能优异等优点引起了广泛的研究兴趣。如今,计算化学已经成为一种研究有机催化机理的强大工具,特别是有机催化剂已经成为计算有机化学中一个重要而活跃的领域。因此,本论文运用密度泛函理论(DFT)研究了两类具有代表性的N-杂环卡宾催化碳-碳/杂原子键构筑的反应机理和区域/化学选择性,旨在阐明NHC催化剂高催化活性的来源及反应条件对反应机理的影响。本论文的主要研究内容如下:在B3LYP-D3/6-31G**水平上详细研究了NHC和DBU对催化烯烃与醛氧化环氧化反应的可能机理和区域选择性的影响。NHC催化的反应包括四个步骤:形成苯甲酰溴和Breslow中间体,碳-碳偶联,环氧化及催化剂再生。计算结果表明C–C键的形成是非对映选择性的决定步骤。NCI分析表明π…π堆积和C–H…O相互作用是产生非对映选择性的主要原因。应用前线分子轨道揭示了NHCs是如何通过极性反转策略促进反应的。NHC通过显著增加HOMO轨道能量和适度增加LUMO轨道能量来增强底物的亲核性。DBU作为强碱促进真实催化剂NHC的生成,及α-C(sp)-H脱质子生成关键Breslow中间体。利用M062X/6-31G**对最近报道的芳醛与烷胺的化学选择性分子间S2亲核取代反应提出了可能的催化机理。计算结果表明,催化循环经历了活性NHC对底物醛的亲核进攻、形成Breslow中间体、NBS和醇胺的氧化加成、S2的亲核取代、NHC的再生和产物的形成五个阶段。双分子烷醇胺协助的氧化加成是该反应的化学选择性决定步骤。我们的结果表明,N-溴胺中间体在热力学和动力学上都比次溴酸盐有利14.2 kcal/mol,这与实验中只观察到N-酰化产物的事实一致。此外,我们还发现醇胺不仅可以作为反应物,还可以作为质子传递体和稳定剂,通过多重N?H…N和N?H…O氢键相互作用来稳定化学选择性优势过渡态的结构。EtN首先作为碱促进活性催化剂NHC的形成,然后质子化的EtN作为质子传递体加速Breslow中间体的形成并降低活化势垒。对关键物种进行Parr函数和前线分子轨道分析表明,NHC显著提高底物芳醛的亲核性,并导致HOMO显著增加和LUMO适度增加。我们希望这项工作能对EtN辅助NHC催化的S2取代反应的基本机理提供更深入的理解。

关键词：有机催化 N-杂环卡宾化学/区域选择性反应机理密度泛函理论

Diurnal and Seasonal Variations of Rain Rate and Rain Attenuation on Ku-Band Satellite Systems in a Tropical Region: A Synthetic Storm Techniques Approach

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Journal of Computer and Communications 2015年第4期3卷 1-10页

作者： joseph S. ojo Okeowo C. Rotimi Department of Physics Federal University of Technology Akure Nigeria Department of Physics College of Education Ikere-Ekiti Nigeria

In this paper, a time-varying rain characterization and diurnal variation in the Ku-band satellite systems simulated with synthetic storm techniques (SST) over a tropical location in Nigeria have been presented. Three years’ rain rate time-series data measured by a raingauge located inside the Federal University of Technology Akure, Nigeria were utilized for the purpose of this work. The analysis is based on the CDF of one-minute rain rate;time-series simulated annual/seasonal and diurnal rain rate, rain attenuation statistics and fade margins observed over four time intervals: 00:00-06:00, 06:00-12:00, 12:00-18:00 and 18:00-24:00. In addition, comparison was also made between the synthesized values and rain attenuation statistics, at 12.245 GHz for a hypothetical downlink from EUTELSAT W4/W7 satellite in the area. It could be observed that at 99.99% link availability, the fade margin as high as ~20 dB may be required at Ku band uplink frequency bands in this area. We also observed that the communication downlinks working in the early morning and early to late in the evening hours must be compensated with an appropriate Down-Link Power Control (DLPC) for optimum performances during severe atmospheric influences in the region.

关键词： Diurnal and Seasonal Ku-Band Frequencies TRODAN Data Synthetic Storm Technique Tropical Location

Effects of heavy metal(Pb) concentration on some growth parameters of plants grown in lead polluted soil under organic fertilizer amendment

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Research in Cold and Arid Regions 2016年第1期8卷 36-45页

作者： ojo M.Oseni Adekunle A.Adelusi Esther O.Dada Abdulfatai B.Rufai Department of Botany Faculty of ScienceObafemi Awolowo University Department of Biological Sciences(Ecology and Environmental Studies Unit) Joseph Ayo Babalola University

This study investigated morphological variation and biomass accumulation that occurred in Sida acuta and Chromolaena odorata plants grown in lead polluted soil under organic fertilizer amendment. The study was carried out in the screen house at the Biological Gardens of the Obafemi Awolowo University, Ile-Ife, Osun State. The experiment was a factorial combination of one heavy metal （Pb） at five levels of concentration （0, 200, 400, 800 and 1,000 mg/kg） in a completely randomized design, and were replicated three times for each of the two plants and two levels （0 g/kg and 9.4 g/kg） of organic fertilizer （OBD-Plus）. Each pot was filled with 5 kg of air-dried and sieved soil and placed on a plastic tray for the collection of excess water. Two weeks after planting, seedlings of uniform height were transplanted from the nursery to experimental pots at the rate of one seedling per pot and grown for 10 weeks. The growth parameters of the plants were biomonitored for 7 weeks. After 10 weeks of treatment, the plants were harvested and dried to calculate the biomass accumulation. The two plant species performed better under fertilizer application than without it. For each of the plant species the growth parameters decreased as the levels of Pb concentration increased. Furthermore, the plants＇ biomass decreased significantly （p 〈0.05） as the levels of Pb concentration increased. The organic fertilizer helped to improve the plants＇ performance in lead-polluted soil.

关键词： morphological variation organic fertilizer lead biomonitored biomass

Presentation of Undescended Testis to a Paediatric Referal Centre in Jos

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Open Journal of Pediatrics 2020年第3期10卷 438-446页

作者： Andrew Haruna Shitta Solomon Danjuma Peter Ezekiel Dido Dung Danaan joseph Shilong Alexander Femi Ale Mercy Wakili Isichei Emmanuel Olorundare ojo Michael Ayedima Misauno Lohfa Bali Chirdan Department of Surgery Jos University Teaching Hospital Jos Nigeria

Background: Undescended testis is the commonest disorder affecting the male urogenital tract. Late presentation has significant socio-medical impact on the individual’s quality of life. Aim: To evaluate the presentation of undescended testis and age at surgery in our centre. Methods: A 9-year retrospective analysis of the clinical records of patients Results: A total of 73 records were analysed, 58 (79.5%) presented > 1 year. Median age at presentation was 4 years, range 1 day - 16 years. Males 73 (100%), only 17 (23.3%) were referred by health personnel, while 56 (76.7%) self-referred. Commonest site involved was the left 33 (45.2%), 29 (39.7%) right and 11 (15.1%) bilateral. There were 13 (17.4%) who had associated congenital malformations. Hypospadias 7 (53.8%), isolated micropenis 4 (30.8%) and 1 each (7.7%) had myelomeningocele and hernia. Median age at presentation for bilateral involvement was 30 days, with associated hypospadias was 12 days, while those with isolated micropenis was 7.5 years. Median age at surgery for bilateral involvement was 2 years, overall median age at surgery was 4 years. Surgery Findings: Supra-scrotal testis 47, canalicular 25 (34.2%), and bilateral abdominal 1 (1.4%). Outcome: Wound infections 4 (5.5%), scrotal wound breakdown 1, Recurrence 3 and testicular atrophy 1. <

关键词： Undescended Testis Age at Presentation Orchidopexy

Endometriosis Misdiagnosed as a Metastatic Ovarian Tumour

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Case Reports in Clinical Medicine 2019年第7期8卷 189-195页

作者： J. O. Imaralu M. A. Ajani M. A. Adesina N. K. ojo Department of Obstetrics and Gynaecology Babcock University Teaching Hospital Ilishan-Remo Nigeria Department of Pathology Babcock University Teaching Hospital Ilishan-Remo Nigeria Department of Surgery Babcock University Teaching Hospital Ilishan-Remo Nigeria Department of Radiology Babcock University Teaching Hospital Ilishan-Remo Nigeria

Endometriosis is a debilitating problem with pain in the short term and high risk of infertility later. It is an oestrogen-dependent condition found in about 10% of women of reproductive age, about 1/3 of infertile women and as high as 80% of women with chronic pelvic pain. The condition is not well understood and thus associated with misdiagnosis and delayed diagnosis. Higher rates of misdiagnosis occur in blacks and this is especially for pelvic tumors-fibroids and ovarian tumors. We present here the case of a 30-year-old nullipara, who had an umbilical nodule (Sister Mary joseph’s) and was found on imaging to have a pelvic tumor which was suspected to be an ovarian cancer. Diagnostic laparoscopy during the menstrual phase however revealed endometriosis in early stage. Misdiagnosis of endometriosis has potential to distort the course of the disease and endanger fertility prospects;early laparoscopic evaluation of patients with unclear pelvic pathologies would help to prevent this occurrence.

关键词： Diagnosis Endometriosis Pelvis Tumour Treatment Imaging

Possible Aquaculture Development in Nigeria： Evidence for Commercial Prospects

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Journal of Agricultural Science and Technology(B) 2017年第3期7卷 194-205页

作者： Amosu Albert Oluwatobi Hammed Ayofe Mutalib Togunde Kasaliyu Adeniyi joseph Olufemi Olabode Adekoya Adeyemi Department of Biodiversity and Conservation Biology Faculty of Natural Sciences University of the Western Cape Private BagX17 Bellville 7535 South Africa Department of Agricultural Science School of Vocational and Technical Education Adeniran Ogunsanya College of EducationOtto/ljanikin PMB 007 Festac Town Lagos Nigeria Department of Fisheries Faculty of Science Lagos State University P.O. Box 0001 LASU Post Office Ojo Lagos Nigeria

The cultivation of desirable aquatic organisms is becoming increasingly important as one of the fastest-growing agro-industrial activities in the world. Nigeria, over the years, practised traditional methods of aquaculture in tidal pools and floodplains of inland waters. Recently, the coastal region has been the focus of aquaculture development with introduction of cage culture system. Nigeria is one of the top aquaculture producers in Africa with numerous opportunities for large-scale production, and 80% of production is from small-scale farmers who involve in brackish and freshwater cultivation, except mariculture which has several setbacks. Nigeria is yet to show feasible interest in non-fed aquaculture （macroalgae） which is among the world＇ s most efficient mass producer of proteins and other products. Constraints to production in the industry have been identified, while the prospects can be achieved by expanding aquaculture zones, enhancing management practices of production systems and improving product quality with the resultant creation of jobs, regular income and investment, etc.. This paper explores the status of aquaculture in Nigeria, and the components and the systems of commercial aquaculture were elucidated.

关键词： Aquaculture commercial fish fanning macroalgae mariculture industry.