Temperature dependency of the group interaction parameters in the AGSM and UNIFAC models for the prediction of heats of mixing

A four-parameter group-contribution model (UNIFAC) has been developed for the prediction of heats of mixing of non-electrolyte mixtures. Both the UNIFAC and AGSM models are evaluated over a wide range of temperature dependencies of the group interaction parameters. The UNIFAC model has been chosen over the AGSM model and an optimum parameter-temperature relationship has been established. Adopting the optimum temperature dependency, group inter-action parameters have been calculated using UNIFAC for the prediction of four types of mixtures: n-Alcohols/n-Alkanes; Benzene/n-Alkanes; Nitriles/n-Alkanes; Amines/n-Alkanes

DETERMINING POWER SYSTEM FAULT LOCATION USING NEURAL NETWORK APPROACH

Fault location remains an extremely pivotal feature of the electric power grid as it ensures efficient operation of the grid and prevents large downtimes during fault occurrences. This will ultimately enhance and increase the reliability of the system. Since the invention of the electric grid, many approaches to fault location have been studied and documented. These approaches are still effective and are implemented in present times, and as the power grid becomes even more broadened with new forms of energy generation, transmission, and distribution technologies, continued study on these methods is necessary. This thesis will focus on adopting the artificial neural network method for fault location for a high-impedance grounded system, where fault currents are small for single phase to ground faults. This approach will be performed on a single 2-terminal distribution network. This thesis will also give a comprehensive explanation on the process of developing artificial neural networks (ANN) using MATLAB’s neural network app designers. The main objective of the experimental approach is to investigate the effects of different variations in ANN structures (such as number of neurons, number of hidden layers, input features, and data preprocessing) on predicting fault locations. Study results from the simulations have been presented to show performance of each ANN structure for fault location on the sample distribution system

Relationship between admission serum C-reactive protein and short term outcome following acute ischaemic stroke at a tertiary health institution in Nigeria

Background: There is evidence of an association between mediators of inflammation, particularly C-reactive protein (CRP), and outcome of acute ischaemic stroke. This provides a potential opportunity for interventions aimed at improving outcome. There is sparse data exploring the role of inflammatory markers such as CRP and stroke outcome in Africans. The study objective was to determine the association between admission serum CRP levels and short-term outcome in the Nigerian patient presenting with acute ischaemic stroke.Materials and Methods: Consecutive patients hospitalized for first-ever acute ischaemic stroke at the Lagos University Teaching Hospital, Lagos, Nigeria, were prospectively enrolled between October 2007 and June 2008. Stroke severity was assessed using the National Institutes of Health Stroke Scale (NIHSS). Serum CRP was determined on samples obtained within 7 days of stroke onset. All stroke patients were followed up till day 30 post-stroke. Outcome measures were 30 day Glasgow outcome scale score and functional impairment on the modified Rankin Scale (mRS). An age- and gender-matched healthy control group had serum CRP determined at inclusion. Elevated CRP was defined as any level above the cutoff (mean +2 x standard deviation of CRP level of controls).Results: Eighty patients with acute ischaemic stroke (47 men and 33 women) and 40 controls (27 male and 13 female) (P = 0.47) were studied. Mean age in cases was 59.1 ± 15.0 years. Mean CRP was significantly higher in stroke cases than controls (17.7 ± 14.4 mg/L versus 1.1 ± 1.7 mg/L respectively) (P < 0.00001). The frequency of elevated CRP (>4.5 mg/L) was 76.3% in stroke (N = 61) and 5% (N = 2) in controls (P < 0.0001). The case fatality rate in stroke with elevated CRP (32.8%) was significantly higher than stroke with normal admission CRP (0%; P= 0.015). The association of higher admission CRP with fatality () was statistically significant (P < 0.0001). Amongst survivors, mean CRP levels were markedly higher in the patients with unfavorable motor outcome (moderate/severe disability; n = 22; 21.5 ± 11.1) compared to those with favorable outcome (mild disability; n = 38; 6.5 ± 6.2) (P < 0.00001). In multivariate regression analysis, only high NIHSS score (P = 0.004) and admission CRP (P = 0.008) were independently associated with case fatality.Conclusions: Elevated admission CRP and high NIHSS score are independent predictors of short-term case fatality and adverse functional outcome following acute ischaemic stroke in Nigerians.Key words: C-reactive protein, ischaemic stroke, outcom

Influence of Age and Neurotoxic HAART Use on Frequency of HIV Sensory Neuropathy

Background. Sensory neuropathy (SN) is one of the most common AIDS-associated neurologic disorders especially in the era of highly active antiretroviral therapy (HAART). The aim of this study was to determine the prevalence of SN among highly-active-antiretroviral-therapy- (HAART-) experienced and HAART-naïve HIV-positive individuals and to investigate the relationship to demographic, clinical, and laboratory factors. Methods. 323 patients with HIV infection (142 on HAART and 181 HAART naïve) were enrolled in a cross-sectional neuropathy screening program. Data was collected using structured questionnaires which contained the brief peripheral neuropathy screening tool of AIDS Clinical Trial Group protocol. Neuropathy was defined by the presence of at least 1 clinical sign in a distal, symmetrical pattern. Patients were classified as symptomatic if they described aching, stabbing, or burning pain, paresthesia, or numbness in a similar distribution. Demographic, clinical, and laboratory details were documented as risk factors. Result. The prevalence of sensory neuropathy was 39.0% (126/323), (of which 29/126 (23%)) were symptomatic. Amongst those on HAART, 60/142 (42.3%) had SN compared to 66/181 (36.5%) HAART-naïve individuals (P = 0.29). On multivariate analyses, the independent associations with SN were increasing age (P = 0.03) and current exposure to stavudine (P = 0.00). Gender (P = 0.99) height (P = 0.07) use of HAART (P = 0.50), duration of HAART treatment (P = 0.10), and lower CD4 count (P = 0.12) were not associated with an increased SN risk. Conclusion. HIV SN remains common despite improved immunologic function associated with HAART and decreased neurotoxic HAART use. In this cross-sectional analysis, age and stavudine-based therapies were the independent risk factors

Comparison of the Minimental State Examination Scale and the International HIV Dementia Scale in Assessing Cognitive Function in Nigerian HIV Patients on Antiretroviral Therapy

Introduction. HIV-associated neurocognitive disorder (HAND) remains common despite the availability of antiretroviral therapy. Routine screening will improve early detections. Objective. To compare the performance of the minimental state examination (MMSE) and international HIV dementia scale (IHDS) in assessing neurocognitive function in HIV/AIDS patients on antiretroviral therapy. Methods. A case-control study of 208 HIV-positive and 121 HIV-negative individuals. Baseline demographic data were documented and cognitive function assessed using the two instruments. CD4 cell counts were recorded. Results. Cases comprised 137 females and 71 males. Controls were 86 females and 35 males. Mean MMSE score of cases was 27.7 ± 1.8 compared to 27.8 ± 1.3 in controls (P = 0.54). Mean IHDS score in cases was 8.36 ± 3.1 compared to 10.7 ± 0.9 in controls (P < 0.001). Using the MMSE scale, 6 cases but no controls had HAND (P = 0.09). Using the IHDS, 113 (54.3%) had HAND compared with 10 (8.3%) controls (P < 0.0001). Using IHDS, 56.5% cases with CD4 count > 200 had HAND compared with 92.5% with CD4 count < 200 (P < 0.001). Conclusion. These findings indicate that the IHDS detects higher rates of HAND and may identify HIV/AIDS patients who require further cognitive assessment using more robust assessment batteries

Renal dysfunction and 30-day mortality risk in patients with acute stroke

Background: Chronic kidney disease (CKD) and stroke constitute worldwide public health problems with rising incidence, prevalence and poor outcomes. While the link between renal dysfunction and myocardial infarction is well established, the link with stroke has been less well investigated. In this study, the prevalence and prognostic implication of renal dysfunction in patients admitted with acute stroke was assessed.Methods: This was a prospective observational study of 130 patients with first-ever stroke admitted within 7 days of stroke onset and followed up for 30 days. The study outcome measure was 30-day mortality. Stroke subtype was verified by a computerized tomography (CT) scan of the brain. Estimated glomerular filtration rate (eGFR) was calculated from serum creatinine using the 4-variable Modification of Diet in Renal Disease (MDRD) equation. Renal dysfunction was defined as eGFR &lt; 60 mL/min/1.73 m2 and significant proteinuria was defined as urinary protein excretion ≥ 0.5 g in 24 hours. The Cox proportional hazards regression model was used to determine the relationship between GFR, proteinuria and 30-day mortality.Results: The majority of the patients studied (56%) were male and their mean age was 61.3 ± 13.9 years. Ischaemic stroke was the most common stroke subtype, accounting for 74% of all cases. Overall, 38% of patients had reduced eGFR &lt; 60 mL/min/1.72 m2 while 35% had significant proteinuria. eGFR &lt; 60 mL/min/1.73 m2 (hazard ratio, HR 3.59, 95% CI 1.03–13.26, p &lt; 0.001) and proteinuria (HR 1.86, CI 1.00–8.14, p = 0.035) were independent predictors of mortality. Other independent predictors were age &gt; 70 years, haemorrhagic stroke subtype, CNS score &lt; 6.5 and random blood glucose &gt; 7.8 mmol/L.Conclusions:Renal dysfunction is common among adult Nigerian patients with acute stroke. Both reduced eGFR and proteinuria were independent predictors of 30-day mortality in these patients

Prevalence and Potential Risks of Antibiotic Resistance in Streptococcus agalactiae Isolates in Human and Non-Human Models Collected from Ituku-Ozalla, Enugu in South East Nigeria

Streptococcus agalactiae, a pathogen within the Streptococcaceae family, is significant for its role in neonatal infections, bovine mastitis, and zoonotic threats. Initially identified in animals, particularly in cases of bovine mastitis, S. agalactiae has also become a concern for human health, raising alarms about interspecies transmission, especially in regions with close human-animal contact. The extensive use of antibiotics in both human and veterinary medicine has accelerated the emergence of multi-drug-resistant (MDR) strains, complicating treatment efforts. Consequently, the objective of this paper was to investigate the prevalence and potential risks of antibiotic resistance in S. agalactiae isolates in human (pregnant and non-pregnant women) and non-human (cow’s milk and fish tissue of catfish and Tilapia) models collected from Ituku-Ozalla, Enugu in South East Nigeria using appropriate standard procedures. Data obtained show that the percent (%) antibiotic resistance in human and non-human models were Ampicillin 55.6 and30; Penicillin 31.5 and 30; Erythromycin 27.8 and 35; Ceftriaxone 22.2 and 40; Chloramphenicol 46.3 and 20; Tetracycline 20.4 and 50 Gentamicin 42.6 and 40; Ofloxacin 25.9 and 35 and Ciprofloacin16.7 and 40 respectively.  Significant antibiotic resistance was observed, particularly in human isolates against Ampicillin and Penicillin. On the other hand, non-human isolates exhibited higher resistance to Tetracycline, likely due to its widespread use in livestock. These findings indicate varying patterns of resistance between human and non-human isolates. The results emphasize the need for stricter antibiotic stewardship and surveillance to prevent the spread of MDR strains, especially in areas where human-animal interactions are common. Addressing these challenges is critical for public health, particularly in Nigeria, where the risks associated with interspecies transmission are pronounced

Prescription patterns and therapeutic gaps among persons with epilepsy in Southwestern Nigeria

Introduction: Pharmacotherapy with antiseizure medications (ASMs) has been a cornerstone for achieving long-term remissions in persons with epilepsy (PWEs). This study aims to determine the prescription patterns and treatment gaps (TGs) among PWEs.Methods: Accordingly, a descriptive cross-sectional study was conducted with 940 PWEs aged ≥18 years having clinically confirmed diagnosis of epilepsy based on the International League Against Epilepsy (ILAE) criteria. At a scheduled interview with each participant, a previously established questionnaire was used to obtain clinical information relating to epilepsy in terms of the age of onset, etiology, duration of epilepsy, frequency, types, and number of ASMs used.Results: There were fewer male participants [445 (47.4%) vs. 495 (53.6%)] than females, with a higher mean age of onset [(35.19 ± 21.10 vs. 31.58 ± 20.82 years; p = 0.009]. The medication characteristics showed that 336 (35.7%) of the 940 PWEs recruited were not on any ASMs, whereas the remaining 604 (64.3%) patients were on ASMs, with 504 (83.4%) on monotherapy vs. 100 (16.6%) on polytherapy. The PWEs on ASM monotherapy had a higher mean age [40.92 ± 19.40 vs. 33.61 ± 16.51 years; p &lt; 0.001] and higher mean age of onset [34.47 ± 21.80 vs. 25.39 ± 19.78 years; p &lt; 0.001] than those on polytherapy. Furthermore, there were more persons on ASM monotherapy among the participants with seizure duration &lt; 2 years [251 (87.5%) vs. 36 (12.5%)] and seizure duration &gt; 2 years [253 (79.8%) vs 64 (20.2%)].Conclusion: The majority of the participants receiving ASMs were on monotherapy, with carbamazepine being the most frequently prescribed medication. Furthermore, about a third of the participants had TGs; therefore, healthcare providers should focus on alleviating the TGs among PWEs

Emotional Intelligence as a Predictor of Research Skills Acquisition Among University Students with Intellectual Disabilities in Calabar, Nigeria

Aim: Intellectual disability is characterized by significant limitations in intellectual functioning and adaptive behavior originating before age 18 (AAIDD, 2010). In higher education, these students often require individualized support, yet inclusive practices in Nigerian universities remain underdeveloped. This study examines the predictive relationship between emotional intelligence and research skills acquisition among university students with intellectual disabilities at the University of Calabar (UNI.CAL) and the University of Cross River (UNICROSS), Cross River State, Nigeria. Five study objectives were stated to guide the research. Five research questions were formulated, and three hypotheses were stated. Literature was reviewed based on the variables under study, as research gaps were also stated. Method: The study adopted a correlational survey research design. The area of the study is Cross River State, South-South, Nigeria. The study population consists of all 20,030 final-year undergraduate students with intellectual disabilities in inclusive departments of the University of Calabar and the University of Cross River State, offering special education or support for students with disabilities. A purposive sampling technique was used to select students identified with intellectual disabilities. A sample size of 401 participants was selected based on accessibility and consent. The instrument for data collection was a questionnaire. Cronbach Alpha reliability coefficient method was used in establishing the reliability index of .82. Results of the research questions were presented using frequency counts, percentages, mean and standard deviation, and Pearson's Product Moment Correlation, Multiple linear regression, and Independent t-test were used to analyze the research question and hypotheses. Results: The results revealed that emotional intelligence significantly contributes to developing research skills in students with intellectual disabilities. Emotional competencies such as self-awareness, motivation, and interpersonal sensitivity are essential tools in enabling these students to participate fully in research activities. Hence, emotional intelligence components collectively predict research skills acquisition. There is a significant difference between male and female students with intellectual disabilities in their level of research skills acquisition. Conclusion: This research concluded that there is a statistically significant relationship between emotional intelligence and the ability to develop and perform research tasks. It affirms the critical role emotional intelligence plays not just in social functioning but also in academic productivity, especially among students who often face exclusion or limited support. Recommendation: Universities should incorporate emotional intelligence training into their special education and general academic programs to build students’ self-efficacy and research competence

Awareness of warning signs among suburban Nigerians at high risk for stroke is poor: A cross-sectional study

<p>Abstract</p> <p>Background</p> <p>Although stroke is a leading cause of morbidity and mortality in Nigeria, there is no information on awareness of its warning signs. This study was designed to assess awareness of stroke warning signs in Nigerians at increased risk.</p> <p>Methods</p> <p>A hospital-based cross-sectional study conducted at Irrua Specialist Teaching Hospital, in southern Nigeria. Patients with a diagnosis of hypertension, diabetes or both were interviewed for the warning signs of stroke in the outpatient clinic by trained interviewers. The main outcome measure was ability to identify at least one stroke warning sign.</p> <p>Results</p> <p>There were 225 respondents with a mean age of 58.0 ± 11.7 years. Only 39.6% could identify at least one stroke warning sign while the commonest sign identified was sudden unilateral limb weakness (24.4%). On multivariate logistic regression analysis, male sex (β = 0.26, 95% CI = 0.14–0.39, p < 0.001) and 11 or more years of education (β = 0.16, 95% CI = 0.03–0.29, p = 0.02) emerged the independent predictors of ability to identify at least one warning sign.</p> <p>Conclusion</p> <p>Awareness of stroke warning signs is poor among Nigerians at increased risk for the disease. Efforts should be made to improve on the level of awareness through aggressive health education.</p