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The Journal of Biomedical Research 2023年第2期37卷 100-114页

作者： Solomon E.owumi uche o.arunsi Moses T.otunla Imisioluwa o.oluwasuji Cancer Research and Molecular Biology Laboratories Department of BiochemistryFaculty of Basic Medical SciencesUniversity of IbadanIbadanOyo State 200004Nigeria Department of Cancer Immunology and Biotechnology School of MedicineUniversity of NottinghamNottingham NG72RDUK

Lead(Pb) and furan are toxic agents, and persistent exposure may impair human and animal reproductive function. We therefore explored the effects of Pb and furan on male rat hypothalamic-pituitary-gonadal reproductive status, oxidative stress, inflammation, and genomic integrity. We found that co-exposure to Pb and furan reduced the activities of testicular function enzymes, endogenous antioxidant levels, total sulfhydryl group,and glutathione. Sperm abnormality, biomarkers of oxidative stress, inflammation, and p53 expression were increased in a dose-dependent manner by treatment with furan and Pb. Typical rat gonad histoarchitecture features were also damaged. Conclusively, co-exposure to Pb and furan induced male reproductive function derangement by decreasing the antioxidant defences in rats, increasing abnormalities in spermatozoa morphology, and reducing reproductive hormone in circulation. These pathophysiological alterations, if persistent, might provide a permissive environment for potentiating reproductive dysfunction and infertility.

关键词： infertility furan lead acetate oxidative stress DNA damage inflammation

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optimization of bio-oil production parameters from the pyrolysis of elephant grass (Pennisetum purpureum) using response surface methodology

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Clean Energy 2024年第5期8卷 241-251页

作者： Sunday C.Ikpeseni Samuel o.Sada Ufuoma J.Efetobor Henry o.orugba Mathias Ekpu Hilary I.owamah Jeremiah L.Chukwuneke Solomon oyebisi uche P.onochie Department of Mechanical Engineering Delta State UniversityP.M.B.1AbrakaNigeria Department of Mechanical Engineering Delta State PolytechnicP.M.B.3Otefe-OgharaNigeria Department of Chemical Engineering Delta State UniversityP.M.B.1AbrakaNigeria Department of Civil Engineering Delta State UniversityP.M.B.1AbrakaNigeria Department of Mechanical Engineering Nnamdi Azikiwe UniversityP.M.B.2025AwkaNigeria Department of Civil Engineering Covenant UniversityP.M.B.1023OttaNigeria Department of Civil Engineering The University of the South PacificP.M.B.9072SuvaFiji Department of Mechanical Engineering Delta State University of Science and TechnologyP.M.B.5OzoroNigeria

The need to increase bio-oil yield from biomass and enhance its fuel properties has driven research into optimizing the pyrolysis *** study investigated the influence of three key process parameters—temperature,heating rate,and nitrogen flow rate—on the pyrolysis of elephant grass(Pennisetum purpureum)in a fixed-bed *** surface methodology was used to study the im-pact of the aforementioned variables on bio-oil yield to improve its production *** analysis of the biomass revealed 79.24 wt%volatile matter,14.22 wt%fixed carbon,and 5.86%ash,with ultimate analysis showing 45.44%carbon,5.59%hydrogen,and 40.95%*** high volatile matter content and favourable carbon and hydrogen percentages indicate that elephant grass is a vi-able energy source due to its potential for high bio-oil yield and energy *** resulting bio-oil exhibited a higher heating value of 20.9 MJ/kg,indicating its suitability for various heating applications.A second-order regression model was developed for bio-oil yield,with optimal conditions identified as a temperature of 550°C,a heating rate of 17°C/min,and a nitrogen flow rate of 6 ml/*** study achieved an optimal bio-oil yield of 59.03 wt%,and the model’s high R²value of 0.8683 from analysis of variance analysis confirmed its predictive *** research highlights elephant grass as a sustainable feedstock for bio-oil production,offering valuable insights into optimizing pyrolysis conditions to enhance bio-oil yield,thus advancing biofuel technology.

关键词： renewable energy biomass sustainable feedstock regression model fixed-bed reactor

Morphometry and Significance of Collodiaphyseal Angle among Bini Tribe in Southern Nigeria

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Journal of Forensic Science and Medicine 2024年第1期10卷 20-23页

作者： Dayo Rotimi omotoso uche Christiana okwuonu Emmanuel olusola Yawson Paul olugbemiga Awoniran Department of Human Anatomy Redeemer’s UniversityEdeOsun StateNigeria Department of Anatomy Igbinedion UniversityOkadaEdo StateNigeria

Introduction:The collodiaphyseal angle(CDA)is an angle formed between the femoral neck and femoral shaft *** is a vital determinant of femoral neck fracture as narrower angle is often used as a predictor of stress *** is also important in orthopedic treatment planning,especially hip replacement ***:This study was carried out to evaluate the CDA values among the Bini tribe and elucidate its ***:This study employed 200 anterior-posterior pelvic radiographs of the Bini tribe(100 males and 100 females)aged between 25 and 55 years obtained from selected radiological diagnostic centers in Benin City,Nigeria,after obtaining the Institutional Ethical *** were used to evaluate the right and left CDA as an angle formed by intersection of the femoral neck and shaft axes and measured using the *** were statistically analyzed using IBM-SPSS(version 20)with the mean,standard deviation,and range evaluated,and side and gender comparisons were done using t-test,and Powed significant gender differences bilaterally(Powever,the bilateral differences in the CDA were not statistically significant among either male or female Binis(P>0.05).Conclusion:The CDA can be employed as a morphometric indicator of sexual differences and for other clinical applications.

关键词： Bini tribe collodiaphyseal angle human morphometry Nigeria

Marriage-Age and Fertility Pattern among Reproductive Age Women in Abakaliki, Ebonyi State, South East Nigeria

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open Journal of obstetrics and Gynecology 2024年第9期14卷 1449-1462页

作者： Johnson Akuma obuna Nkiruka Bridget uche-Nwidagu Department of obstetrics and Gynaecology Ebonyi State University Abakaliki Nigeria National obstetric Fistula Centre Abakaliki Nigeria

Introduction: In Nigeria, one of the major reasons for marriage is procreation and married couples look forward to having children within a year or two of marriage. The age of marriage is on the increase in this part of the world. Many women are now increasingly getting engulfed in career and academic pursuits at the detriment of early marriage. Many men are also not interested in marrying women who have no job. There is age-related acceleration of primordial follicle depletion which is of great clinical importance because it is associated with a significant decrease in fecundity. objective: This study assessed the ages of the marriage of women who attended Fertility and Antenatal clinics at the National obstetric Fistula Centre and Smile Specialist Hospital, Abakaliki, and their relationship with the fertility pattern of these women. Methods: This was a cross-sectional study of 352 consenting married women who sought and received fertility and Antenatal care at the National obstetric Fistula Centre and Smile Specialist Hospital Abakaliki, South-East Nigeria between February 1, 2022 and January 31, 2024. Semi-structured questionnaires were administered to the participants over a two-year period. Data was analyzed using IBM SPSS version 20. A test of statistical significance was done using Chi Square. Results: The age group with the highest education was 26 - 30. This was statistically significant (X2 = 90.893, P-value 2 = 294.555, P-value 2 = 173.007, p-value 2 = 129.494, P-value 2 = 169.300, p-value 2 = 279.230, p-value Conclusion: There is increased difficulty at conception at marriage age above 25 years. The major reasons for delayed marriage were academic pursuit and lack of gainful employment. Education of the masses and inclusion of biological dynamics of the female reproductive behaviours as part of the core school curriculum will help enlighten the female and the male folks alike to enable them to make informed decisions with regard to the timing of marriage

关键词： Fertility Reproductive Age Women Marriage-Age Conception-Age

Evaluation of Phytochemical Contents and Antimicrobial Activities of Pandiaka heudelotii

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Advances in Biological Chemistry 2024年第2期14卷 55-63页

作者： Ikenna obiora Alaekwe uche Eunice Ekpunobi Vincent Ishmel Egbulefu Ajiwe Chinedu Chris Aguoma Jamilu Ahmad Department of Chemistry Federal University Gusau Gusau Nigeria Department of Pure and Industrial Chemistry Nnamdi Azikiwe University Awka Awka Nigeria

The work investigated the secondary metabolites present in different parts of the Pandiaka heudelotii plant harvested from Ezira, orumba south local government area of Anambra state, southeastern Nigeria as well as their antimicrobial activity. The objectives were to extract, determine the phytochemicals present, evaluate the antimicrobial potential and determine the zones of inhibition of the root, stem and leaf extracts of the plant. The emergence of antibiotics has decreased the spread and severity of a wide range of diseases. Plant extracts were tested for antibacterial and antifungal activities against Staphylococcus aureus, Escherichia coli, Proteus vulgaris, Streptococcus pyogenes, Bacillus subtelis, Pseudomonas aerogenes, Salmonella typhi, Aspergillus flavus, Aspergillus niger and Candida albicans. The zone of inhibition of extracts was compared with that of standard drugs like Erythromycin, Ciprofloxacin, Fulcin and Fluconazole. The result revealed the inhibition of bacterial and fungal growth with some test organisms. The microbial activity of the plant parts may be due to the presence of various secondary metabolites. The ethyl acetate extracts of Pandiaka heudelotii stood out with a minimum inhibitory concentration (MIC) range of 5 - 10 mg/mL and a minimum bactericidal concentration (MBC)/minimum fungicidal concentration (MFC) of 10 - 20 mg/ml against some test organisms. The plant can thus be worked upon to discover biologically active natural products that may serve as a prelude to the development of new pharmaceutical research undertakings.

关键词： Pharmaceuticals Secondary Metabolites Antibiotics Pandiaka heudelotii Bacteria

Stability analysis of a time-delayed Van der Pol–Helmholtz–Duffing oscillator in fractal space with a non-perturbative approach

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Communications in Theoretical Physics 2024年第4期76卷 22-31页

作者： Yusry o El-Dib Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The time-delayed fractal Van der Pol–Helmholtz–Duffing(VPHD)oscillator is the subject of this paper,which explores its mechanisms and highlights its stability *** time-delayed technologies are currently garnering significant attention,the focus of this research remains crucially relevant.A non-perturbative approach is employed to refine and set the stage for the system under *** innovative methodologies introduced yield an equivalent linear differential equation,mirroring the inherent nonlinearities of the ***,the incorporation of quadratic nonlinearity into the frequency formula represents a cutting-edge *** analytical solution's validity is corroborated using a numerical *** conditions are ascertained through the residual Galerkin ***,it is observed that the delay parameter,in the context of the fractal system,reverses its stabilizing influence,impacting both the amplitude of delayed velocity and the *** analytical solution's precision is underscored by its close alignment with numerical ***,the study reveals that fractal characteristics emulate damping *** its applicability across diverse nonlinear dynamical systems,this non-perturbative approach emerges as a promising avenue for future research.

关键词： Van der Pol-Helmholtz-Duffing oscillator fractal space time-delay non-perturbative approach stability analysis El-Dib's frequency formula

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Sensing nanoscale electromagnetic forces when the heat is on

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National Science Review 2024年第7期11卷 64-65页

作者： Eric o.Potma Department of Chemistry University of California

In scanning probe microscopy(SPM),a sharp tip scans across a sample to produce an image with nanometer-scale resolution or better. SPM contrast is derived from the physical interplay between the tip and the sample. A special class of SPM techniques measures forces when the tip–sample junction is illuminated by an external light source. Photo-induced forces can be sensitive to the optical properties of the sample, thus enabling nanoscale imaging with spectroscopic,material-specific contrast.

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Assessment of Heavy Metal Exposure in Soils of Ihwrekreka Communities, Delta State, Nigeria

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Journal of Geoscience and Environment Protection 2024年第3期12卷 279-303页

作者： Adedoyin olubunmi Bankole Akinyemi olufemi ogunkeyede Taofik Adewale Adedosu uche Udeochu Harrison Agboro Efe Jeffery Isukuru Department of Environmental Management and Toxicology College of Science Federal University of Petroleum Resources Effurun Delta State Nigeria Department of Chemistry Faculty of Science Ladoke Akintola University Oyo State Nigeria Chemistry Program Division of Science and Mathematics College of Arts and Sciences University of the District of Columbia Washington District of Columbia USA Department of Biology and Environmental Science College of Arts and Sciences University of New Haven West Haven CT USA

Crude oil pollution in the Niger Delta, perpetrated by both local communities and industrial actors, has brought about soil pollution with its consequent ecological, human health and food challenges. The purpose of this research was to examine the concentration and distribution of heavy metals in soil from communities contaminated by crude oil in Niger Delta, and to evaluate the potential health risks to residents from exposure to these contaminants. To achieve this, soil samples were collected from the Ihwrekreka community and analyzed for heavy metal content using inductively coupled plasma mass spectrometry (ICP-MS). The analytical results in mg/kg revealed a significant metals pollution level derived from the oil spill in the soil ranging from 4.85 - 17,078 (Cu), 1.01 - 16.1 (Cd), 0.22 - 36.8 (Cr), 8.28 - 40.9 (Ni), 7.51 - 6474 (Pb), and 8.84 - 12,851 (Zn) respectively. Most of the metals were above the permissible limits of World Health organization, with Cu, Zn, and Pb as the most contaminating metals. Lead was found to be the main contributor to the hazard index (HI) values for both children and adults in the study area, with its concentration exceeding the permitted limits set by the WHo and the EC. The hazard index (HI) values of Pb, Cu, Zn, Cd, Ni, and Cr were significantly higher than 1. These findings suggest that the release of heavy metals from an oil-contaminated site may pose a risk to human health and the environment.

关键词： Cancer Exposure Pathway Toxic Metals Health Risks

Making topological protein links using enzymatic reactions

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National Science Review 2024年第3期11卷 50-51页

作者： Roger Castells-Graells Todd o.Yeates Department of Chemistry and Biochemistry University of California UCLA-DoE Institute for Genomics and Proteomics

Proteins are exceedingly complex molecules though, at their heart, they are essentially linear polymers. Pull at their ends and one obtains an extended backbone. While that is true in most cases, some natural proteins... 详细信息

关键词： DESIGN

A synthetic microbial community used as a bioinoculant can overcome rice production constraints in acid soils

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Science China(Life Sciences) 2024年第5期67卷 1085-1086页

作者： Maureen o’Callaghan Shengjing Shi Resilient Agriculture Group AgResearchLincolnChristcurch 8140New Zealand

A customised synthetic microbial community(SynCom)composed of carefully selected rhizosphere-competent bacterial strains improved rice growth,yield and resistance to soil acidity and Al toxicity.

关键词： soil soils rhizosphere

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