Evaluative assessment of a five-phase and three-phase permanent magnet synchronous machine at varied loads and fault conditions.

Multiphase machines are very essential for industrial applications that require high reliability of operation. In this paper, a comparative study of three-phase and five-phase inverter fed permanent magnet synchronous motors (PMSMs) was evaluated with respect to their performance characteristics under a healthy state and during transient disturbances such as varied load and double line to ground faults. To avert inherent high oscillations in speed and torque ripples during fault condition, the machine load was significantly reduced to 1/4th of the full load and a post fault current limiting series dynamic braking resistance (SDBR) with a bypassed switch was introduced to enhance the machine fault tolerant level and improve its operational performance.

Evaluating the efficacy of cognitive restructuring and exposure therapies on secondary school chemistry students' test anxiety: A randomized trial.

Background: This study explored how cognitive restructuring (CR) and cognitive exposure therapy (CET) impacted test anxiety in chemistry students from Nsukka, Enugu State. Three research questions and hypotheses guided the investigation.

Method: A quasi-experimental design with a pretest, posttest, and 2 experimental groups was employed.

Effectiveness of pedometer-based walking programmes in improving some modifiable risk factors of stroke among community-dwelling older adults: a systematic review, theoretical synthesis and meta-analysis.

Background: Pedometer-based walking programs hold promise as a health promotion strategy for stroke prevention in community-dwelling older adults, particularly when targeted at physical activity-related modifiable risk factors. The question arises: What is the effectiveness of pedometer-based walking program interventions in improving modifiable stroke risk factors among community-dwelling older adults?

Method: Eight databases were searched up to December 2, 2023, following the Preferred Reporting Items for Systematic Review and Meta-Analysis protocol. Inclusion criteria focused on randomized controlled trials (RCTS) involving community-dwelling older adults and reported in English.

Longitudinal Studies of Aging in Sub-Saharan Africa: Review, Limitations, and Recommendations in Preparation of Projected Aging Population.

Background And Objectives: The United Nations has projected a 218% increase in older people in Sub-Saharan Africa (SSA) between 2019 and 2050, underscoring the need to explore changes that would occur over this time. Longitudinal studies are ideal for studying and proffering solutions to these changes. This review aims to understand the breadth and use of longitudinal studies on aging in the SSA regions, proffering recommendations in preparation for the projected aging population.

Dynamics analysis of permanent magnet synchronous motor speed control with enhanced state feedback controller using a linear quadratic regulator.

This paper presents a robust speed regulation and control of a permanent magnet synchronous motor (PMSM). A linear quadratic regulator (LQR) based state feedback controller was developed to achieve a successful suppression of periodic disturbance of speed and torque. Sliding mode observer in conjunction with the disturbance observer was deployed in the control of motor speed.

Torque ripples enhancement of a PMBLDC motor propelled through quadratic DC-DC boost converter at varying load.

The characteristic effects of a permanent magnet brushless dc (PMBLDC) motor which is propelled by a quadratic DC-DC boost converter was investigated in this paper. The boost converter applied inductor coupling with semi-conductor switches which operate concurrently to produce a high conversion voltage ratio. Modeling of the PMBLDC motor was presented while simulation was performed using a closed loop control system with different controllers for the enhancement of torque-speed performance at varied load.

Active versus expectant management for premature rupture of membranes at term: A randomized, controlled study.

Objective: To compare the effects on feto-maternal outcomes of expectant versus active management for premature rupture of membranes (PROM) at term.

Methods: This was a prospective randomized (1:1) controlled study involving 86 pregnant-women who received either expectant management (n = 43) or active management with misoprostol (n = 43) for PROM at term. Primary outcome was route of delivery.

Behavioural oncology research in Africa: Lessons from the last two decades and key considerations moving forward.

Objective: To analyse the state of behavioural oncology research in Africa and outline key considerations for future research.

Methods: Five bibliographic databases were searched to identify original English-language articles published between January 2000 and August 2020. The Behavioural Epidemiology Framework was applied to studies with data/findings from Africa to delineate their current state.

Setting priorities for ageing research in Africa: A systematic mapping review of 512 studies from sub-Saharan Africa.

Background: In 2040, the older population's growth rate in sub-Saharan Africa (SSA) will be faster than those experienced by developed nations since 1950. In preparation for this growth, the National Institute on Aging commissioned the National Academies' Committee on Population to organize a workshop on advancing aging research in Africa. This meeting provided a platform for discussing some areas requiring improvement in aging research in SSA regions.

Effects of physical exercises on inflammatory biomarkers and cardiopulmonary function in patients living with HIV: a systematic review with meta-analysis.

Background: Pro-inflammatory cytokines expressed in human immune deficiency virus (HIV) infection, may induce oxidative stress likely to compromise the patency of the airways or damage the lung tissues/cardiac function. However, physical (aerobic and/or resistance) exercise-induced release of heat shock protein, immune function alteration or reduced tissue hypoxia, have been highlighted as possible mechanisms by which increasing physical activity may reduce plasma pro-inflammatory cytokines in uninfected individuals and should be appraised in the literature for evidence of similar benefits in people living with HIV (PLWH). Therefore, we evaluated the effects of physical exercises on 1) inflammatory biomarkers and 2) cardiopulmonary function (VO Max) in PLWH.