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Matlab-based simulations of a three-phase induction motor for dynamic studies
No full textThe aim of this paper is to develop a generalized MATLAB program to study the dynamic behavior of a three-phase induction motor. The d-q axis transformation theory is applied in rotor reference frame to study the motor dynamics. A general-purpose MATLAB program is developed and used for the dynamic simulation of a 5HP, 460V, 60Hz, 4-poles induction motor. The developed program is used to study the effect of variation of Stator Resistance (Rs), Moment of Inertia (J), and Load Torque (TL) at t=0.7sec during transient state. The results obtained show that, the torque-speed characteristic curve and mechanical rotor speed-time characteristics of induction motor depend upon the rotor resistance and the moment of inertia. Also, during the simulation of the motor under loaded torque at t=0.7sec, the results showed an increase in the initial starting torque and it reduces from 2000Nm – 0Nm as the operating time progressed. A sudden residual increase occurred in the torque from 0-1000Nm at the loaded time t=0.7sec, and the mechanical rotor speed increased at starting time from 0-1800rpm with respect to operating time and suddenly experienced a drop from 1800rpm to about 1700rpm at the loaded time of t=0.7 sec. The developed program is particularly useful for machine designers in the manufacture of various types of induction machines
Impact of social media marketing on entrepreneurial orientation and economic sustainability of architectural firms in Nigeria
No full textThe concept that architecture is not market driven profession, as stated in the Architect's Code of Conduct on the advertisement and marketing of professional services, is a misconception in today's reality. Given how competitive the design and construction sectors are, planning and implementing strategic marketing in an architectural business is becoming increasingly unavoidable. The use of social media marketing (SMM) as an entrepreneurial marketing technique has increased in recent years, resulting in multitudinous economic benefits for both customers/clients and firms. Despite this situation, there is competitive economic pressure on organizations' survival, and there is little research on the impact of social media marketing on architectural firms' entrepreneurial orientation and economic sustainability. However, the study aimed to close a research gap in Nigeria's competitive economic environment. The study employed a quantitative research approach and structural equation modelling (SEM) used for the inference analysis which focused causal relationship between the variables. The data was collected from the architects in Nigeria's registered architectural firms through a purposive sample technique and a structured questionnaire. The research findings confirmed that social media marketing predict the entrepreneurial orientation and economic sustainability of architectural businesses in Nigeria. The outcome of this research influence educational curriculum development and the realignment of the professional code of conduct on advertising and marketing to reflect contemporary practice
Gestational Trophoblastic Disease In Irrua Specialist Teaching Hospital, Nigeria: A 5-year Review
No full textBackground: Gestational Trophoblastic Diseases (GTD) is a group of interrelated heterogeneous disease of trophoblastic tissue resulting from abnormal fertilization, characterized by abnormal tissue proliferation. Characteristically, prognosis positively correlates with early diagnosis and treatment.
Objective: The objective was to determine the burden, clinical presentation, management and outcomesof GTD at Irrua Specialist Teaching Hospital, Irrua, Edo State, Nigeria.
Methodology: A five-year descriptive (retrospective) study of histologically confirmed cases of st th GTD managed in ISTH between 1 July, 2016 and 30 June, 2021 was undertaken. Inclusion criteria: patient that were management at the study site, histology confirmation and availability of the case-file for review. Women managed for other gynaecological disorders or those with suspected GTD but no histologic confirmation were excluded from the study. Statistical analysis was done using SPSS version 20.0 and the results were presented in tables.
Results: There were 21 cases of GTD and 4703 deliveries with an incidence of 4.5 per 1000 deliveries. The mean age of participants was 32.9±7.5 years. Partial mole was the commonest histologic type (47.4%), choriocarcinoma (31.6%), complete mole (10.5%), invasive mole and placenta site trophoblastic tumor-PSTT (5.3%) respectively. Abnormal vaginal bleeding was the commonest presenting symptom 89.5% (17/19); others were excessive vomiting 52.6% (10/19) and abdominal pain 36.8% (7/19 ). The treatment modalities included suction curettage (42.1%) , suction curettage and chemotherapy (36.8%), total abdominal hysterectomy and cytotoxic chemotherapy only (15.8%).Serum Beta hCG returned to normal within 4 weeks for molar pregnancy and an average of 6 months for choriocarinoma. Default rate from surveillance was 10/19 (52.6%) while two participants (10.5%) died as cases of choriocarcinoma with advanced disease from late presentation.
Conclusion: Abnormal vaginal bleeding was the commonest presentation of GTD with high default and mortality rates. Therefore, efforts should be geared towards education and awareness to improve early presentation, surveillance and prompt treatment. 
Re: Notice of fifteen (15) days ultimatum and commencement of an indefinite strike action by the Joint Healh Sector Union (JOHESU): Matters arising
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Comparative study of the effect of Ginkgo biloba extract and vitamin c on lead induced hippocampal toxicity in adult male Wistar rats
No full textPharmaceutical and industrial preparations contain lead and exposure to it has been associated to be the cause of neurodegenerative diseases. Therefore, in this current study, we investigated the comparative neuroprotective potentials of graded dose of Ginkgo biloba and Vitamin C in lead-induced alterations in the hippocampus of Wistar rats. Six groups of six adult Wistar rats each contained 36 animals in total. Group A served as the control and received normal tap water. Group B received 100mg/kg body weight of lead only. Group C received 100mg/kg body weight of lead and 200mg/kg body weight of Ginkgo biloba. Group D received 100mg/kg of lead and 250mg/kg of Ginkgo biloba. Group E received 100mg/kg of lead and 1192mg/kg of vitamin C, Group F received 200mg/kg of Ginkgo biloba only. For twenty-one days, all administrations were done orally. The Data were expressed as mean ± SEM and were analyzed. Statistical significance between the means was analyzed using one-way analysis of variance (ANOVA) followed Tukey post-hoc test. P-value < 0.05 was considered statistically significant. There is statistically significant (P= 0.0004) reduction in the percentage body/weight (0.6217±0.05566) of the Vitamin C treated group when compared to the control. The Biochemical analysis revealed that there is a statistically significant (P<0.0001) reduction in the concentration of superoxide dismutase, SOD (25.00 ± 0.6952) and catalase, CAT (25.00 ± 0.2728) in the lead only group when compared with the control. Additionally, treatment with Vitamin C causes a statistically significant (P<0.0001) increase (30.00±0.8021) in the CAT level when compared to the lead group. The histology of the dendate gyrus in lead only group shows distortion with fragmented hippocampal layer. Groups that were treated with Ginkgo biloba and Vitamin C shows gradually normalized cellular assortment of hippocampal layers. However, the group treated with Ginkgo biloba has more healthy cells. Also, the histology of the regions of the hippocampus in lead only group reveals several pyknotic changes, including disorganized pyramidal and grandular neurons within severed fragmented layers. Treatment with Ginkgo biloba and Vitamin C normalized DG architecture with cellular features that is similar to that of the control groups. Furthermore, the group treated with Ginkgo biloba appears healthier. Similarly, treatment with Ginkgo biloba and Vitamin C prevents degeneration of pyramidal neurons and shows pyramidal neurons with normal cell bodies with dendritic and axonal processes. This present study shows that Ginkgo biloba and Vitamin C have similar neuroprotective effects on lead-induced neurotocity in Wistar rats in a dose-dependent manner, with Ginkgo biloba being more effective
Forest Security Appraisal of Community Management Interventions Against Threats of Forest Commons at Offinso North District in Ghana
No full textThe paper examines the viability of community forestry and how community participation affects the effectivenessof forest resource security and management. Both qualitative and quantitative techniques with stakeholders’observations and perceptions of managers’ responses to major threats of forest commons were employed in thisstudy. The paper establishes forest security through comparative analysis and discourse of solely governmentmanagement intervention, solely community (private) management intervention and government-communitypartnership for forest management arrangements which are occurring in the Offinso Forest District of Ghana.The paper concludes that, community involvement in forest management interventions delivers better protectionof forest commons; and the extent and autonomy of local community to participate actively in forest resourcemanagement significantly influences resilience against threats of forest commons. Hence, stronger communityparticipation enhances the effectiveness of forest security efforts. Nevertheless, viability of communityparticipation to deliver effective forest resource security is influenced by adequacy of resources in support ofcommunity forestry, empowerment and sense of ownership of communities for forest common management
Characterization of idempotent elements in a variant of the finite full transformation semigroup
No full textIn this research work, we consider a finite set X with n elements and introduce a systematic discussion of the transformation semigroup on the finite set (namely the full transformation semigroup Tn ) with the aim of studying the variants of this semigroup. There have been many approaches in studying the variant semigroup (i.e Tαn for ∈ Tn ), especially characterizing of Green’s relation and classification of certain Subsemigroups. In this particular work we study and characterize the idempotent elements in a variant of the finite full transformation semigroupTn , and present the findings in the form of results
Correlates of successful transformational educational leadership
No full textThis study investigated the correlates of successful transformational educational leadership th r ough the views and lived experiences of the participants from Talisay City National High School, Cebu, Philippines consisting of two (2) administrative, two (2) non teaching and nine (9) teaching personnel following a qualitative descriptive phenomen ologi c al method utilizing Colaizzi’s (1978) seven steps of data analysis. A s supported by the data extracts of the study, four themes (4) are figured out, to wit: “lead to change,” “harmony amidst diversity,” “profession as passion” and “lead by example”. As revealed, commitment, intra and interrelationship and leader’s influence (lead to change and lead by example) greatly affect the success of transformational educational leadership while financial (profession as passion) aspect revealed to be the least a mong t he five
Chute du prix du pétrole et perspective de l’économie Algérienne en 2022: Oil price drop and perspective of the Algerian economy in 2022
No full textL’article propose de prévoir la structure de l’économie algérienne à l’horizon 2022, suite à la chute du prix mondial de pétrole de 2014 et sa poursuite inégalée en 2020 sous l’effet de COVID 19. La réalisation de cette étude s’est effectuée sur la base des données 1989 – 2018 au moyen du modèle SVARX. La structure de l’économie algérienne post-chute du prix du pétrole se distinguerait, selon nos résultats, par une récession économique. En 2022, le retour, peu probable, à la hausse du prix du pétrole, conjugué à la restriction des importations et par suite de la consommation, augurerait une accalmie de la récession sans plus.
The author proposes to forecast the structure of the Algerian economy by 2022 following the fall in the world price of oil in 2014 and its unequaled continuation in 2020 under the effect of COVID 19. The realization of this study is carried out on the basis of 1989 - 2018 data using the SVARX model. According to our results, the structure of the Algerian economy after the drop in oil prices is characterized by an economic recession. In 2022, the unlikely return to the rise in the price of oil, combined with the restriction of imports and consequently of consumption, would augur a lull in the recession and nothing more
Correlation of serum kisspeptin levels, ovarian kisspeptin expression, and ovarian BMP15 expression in rat model of polycystic ovary syndrome
Get PDFBackground: Kisspeptin is a neuropeptide that has an important role in the female reproductive cycle which is indicated by its role in regulating the hypothalamic-pituitary-gonadal axis.Aims: To analyze the correlation between serum kisspeptin levels, ovarian kisspeptin expression, and ovarian Bone Morphogenic Protein-15 (BMP15) expression in polycystic ovary syndrome (PCOS) model rats.Methods: The research was accurate experimental research with a post-test design-only control group and was carried out from August to October 2022 at the Faculty of Veterinary Medicine Universitas Airlangga. 32 Rattus novergicus rats were divided into a control group and a PCOS model group. Blood serum and ovaries were obtained from all groups. In addition, blood serum was examined for kisspeptin levels by ELISA technique, and kisspeptin expression and BMP15 Ovaries were examined immunohistochemically.Results: Serum kisspeptin levels and ovarian kisspeptin expression of the PCOS model group were not significantly higher than those of the control group (p > 0.05, p > 0.05). The ovarian BMP15 expression of the PCOS model group was not significantly lower (p > 0.05) than that of the control group. Ovarian kisspeptin expression and ovarian BMP15 expression did not significantly correlate with serum kisspeptin levels (p > 0.05). In contrast, there was a significant correlation (p < 0.05) between ovarian kisspeptin expression and ovarian BMP15 expression.Conclusion: Serum kisspeptin levels and ovarian kisspeptin expression of the PCOS model group were not higher than those of the control group, and the ovarian BMP15 expression of the PCOS model group was not lower than that of the control group. There was no correlation between serum kisspeptin levels with ovarian kisspeptin expression and ovarian BMP15 expression. However, a significant correlation was found between ovarian kisspeptin expression and ovarian BMP15 expression