13 research outputs found
A Mathematical Model and Sensitivity Analysis of Lassa Fever with Relapse and Reinfection Rate
In this research paper, we depict an unprecedented four-dimensional ordinary differential equation modeling the dynamic transmission of the Lassa fever virus incorporating relapse and reinfection rate. Recent studies showed that the recovered individuals from Lassa fever can again be susceptible; which contradicted the common assumptions made by different researchers on modeling of Lassa fever. So, this article corrects and states the implications of the assumptions on the population density. The numerical simulations unveil the effect of relapse, reinfection, and treatment rate in the affected population. Performing sensitivity analysis suggests all new incorporated parameters can impact the infection dynamics substantially. The stability analysis was carefully estimated where expression for each compartmentalized variable was calculated at both disease-free and persistence (endemic) equilibrium. Also, the basic reproduction number of the novel model was calculated using the Next Generation Matrix. The analytical results justify that the persistence (endemic) and the disease-free equilibrium are locally and globally asymptotically stable using both Routh Hurwitz Criterion and Comparison Theorem.
Keywords: Lassa fever, Reinfection rate, Relapse rate, Treatment rate, Sensitivity analysis.
 
A Susceptible Exposed Infected Recovered Susceptible (SEIRS) Model for the Transmission of Tuberculosis
In this paper, a deterministic mathematical model was proposed and analyzed to understand the dynamics of tuberculosis based on the SEIRS model. The disease-free equilibrium, the endemic equilibrium, and their stabilities were examined. The R0 (basic reproduction number) was derived using the Next Generation Matrix method and its sensitivity analysis showed that the birth rate and infectious rate were the most sensitive parameters of R0. The behaviour of exposed individuals at the latent period with varied treatment rates were examined through numerical simulation. From the analysis carried out, the effect of variations of the treatments of latent TB shows that it affects the disease burden. This implies that testing and treatment of latent TB are important in preventing it from becoming infectious. The re-infection rate was examined to see the effect it had both on the recovered and susceptible populations. The study concludes by recommending the extension of the model to an age structured model with co-infection with another respiratory infectious disease like COVID-19.
Keywords: Epidemiology; Latent TB treatment; Basic Reproduction Number; sensitivity analysis; numerical simulatio
Evaluation of patients' adherence to chemotherapy for breast cancer
The study aimed to establish the common reasons for non-adherence to
drug treatment among breast cancer patients at the Obafemi Awolowo
University Teaching Hospitals Complex, Ile-Ife, Nigeria over a ten-year
period (Jan 1993 - Dec 2002). Patients' adherence and reasons for
non-adherence to chemotherapy were evaluated using descriptive
statistics. Two hundred and twenty-five breast cancer patients
including 199 females and 6 males with breast cancer were recruited.
12(5.3%) patients had Stage I disease while 126 (56%) were in stage IV.
The non-adherence rate was 80.9% and 111(73%) of the non-adherent
patients were eventually not seen again. Of the one hundred and one
patients who gave reasons for non-adherence, 45% complained of
financial difficulties; 18% thought they were well enough; 15% were
fearful of subsequent operation and 11% were unable to further bear the
drug side effects. In conclusion, the study demonstrated poor economic
status of the patients as one of the major reasons for non-adherence to
cancer chemotherapy in Nigeria. Government subsidy of breast cancer
treatment, improved health education and advocacy complemented by home
visiting to encourage hospital attendance would be required for better
adherence to chemotherapy
Experimental Characterization of Maize Cob and Stalk Based Pellets for Energy Use
The quest for alternative energy sources is gradually shifting from natural fossil fuel to alternative bio-resources especially agricultural waste products due to their reduced pollution risk and sustainability. This study seeks to investigate the suitability of plant residue pellets to produce biomass. The plant residues investigated include corn cob and corn stalk. Three samples produced include 100% granulated corn cob residues, 100% granulated stalks and a composite of 50:50% granulated corn cobs and stalk residues. The mixed residues were pelletized using cassava starch as a binder. The pellets were experimentally analyzed using ultimate, proximate and calorimetry analyses. Among three sets of maize residue pellets investigated, the result of the cob-stalk 50:50% combination show that it has 0.64% nitrogen, 48.57% carbon, 0.38% Sulphur, 6.22% hydrogen, 55.81% oxygen, 3.25% moisture content, 2.20% ash content, 80.0% volatile matter, 17.80% fixed carbon percentage, HHV of 32.9 kJ/kg, an average CO2 value of 563±50 PPM, an average CO value of 100±50 PPM, an average value of 69±4% relative humidity and an average temperature of 27.5±0.5%. The study reiterates that corn stalk is a good bio-fuel and should be encouraged to address the current energy shortfalls in the country
Evaluation of patients' adherence to chemotherapy for breast cancer
The study aimed to establish the common reasons for non-adherence to
drug treatment among breast cancer patients at the Obafemi Awolowo
University Teaching Hospitals Complex, Ile-Ife, Nigeria over a ten-year
period (Jan 1993 - Dec 2002). Patients' adherence and reasons for
non-adherence to chemotherapy were evaluated using descriptive
statistics. Two hundred and twenty-five breast cancer patients
including 199 females and 6 males with breast cancer were recruited.
12(5.3%) patients had Stage I disease while 126 (56%) were in stage IV.
The non-adherence rate was 80.9% and 111(73%) of the non-adherent
patients were eventually not seen again. Of the one hundred and one
patients who gave reasons for non-adherence, 45% complained of
financial difficulties; 18% thought they were well enough; 15% were
fearful of subsequent operation and 11% were unable to further bear the
drug side effects. In conclusion, the study demonstrated poor economic
status of the patients as one of the major reasons for non-adherence to
cancer chemotherapy in Nigeria. Government subsidy of breast cancer
treatment, improved health education and advocacy complemented by home
visiting to encourage hospital attendance would be required for better
adherence to chemotherapy
Evaluation of two methods of preoperative hair removal and their relationship to postoperative wound infection
Evaluation of rural transportation technology: a case study of bicycle and motorcycle trailers
Transportation of goods in rural communities, especially from farms, is one of the major bottlenecks experienced by rural
dwellers. Bicycle and motorcycle trailers have been a major intervention proposed by several studies but, this technology has
not been fully adopted and it has no detailed evaluation report. This study, therefore, evaluates the performance of different
bicycle and motorcycle trailer designs. Three different designs of bicycle trailers (fixed plate design (FPD), convertible
plate design (CPD) and wire mesh design (WMD)) and two designs of motorcycle trailers (FPD and CPD) were developed.
Four performance evaluation tests (laden mass, forward speed, pull and haulage tests and a computer-based simulation of
stress/strain analysis) were carried out. The optimum load capacity (OLC) of WMD bicycle trailer is 100 kg at a speed of 5.2
– 6.3 km/hr, while that of FPD and CPD bicycle trailers are 100 kg at a speed of 3.8 - 4.2 km/hr. The OLC for the FPD and CPD
motorcycle trailer was 200 kg at a speed of 6.2 – 8.4 km/hr. Static structural analysis of the trailer chassis shows that the
maximum stress and strain of the trailers were 2.95 Ă— 106 Pa and 8.22 Ă— 10-6 mm, respectively. This study shows the suitability
of the bicycle and motorcycle trailers in small-scale goods conveyance and its suitability for the rural community
Steri-stripTM versus subcuticular skin closure of paediatric groin wounds: A randomised study
Background: A technique that offers the best chance of an optimal result is most appropriate to be employed for wound closure. Aims: We set out to compare the cosmetic outcome, and wound complication rates associated with clean paediatric groin wounds closed using Steri-Strip™ or subcuticular suturing. Settings and Design: A prospective randomised study. Subjects and Methods: Children of African descent with unilateral and bilateral clean groin wounds were randomised into subcuticular suture skin closure and Steri-Strip™ groups and followed up postoperatively. Cosmetic assessment and outcome were scored based on parents' satisfaction using the visual analogue scale (VAS) and a single Plastic Surgeon assessed pictures of the scars using the Hollander Wound Evaluation Scale (HWES). Statistical analysis was used SPSS version 18. Results: Seventy-five wounds were assessed, (n = 35, Steri-Strips™) and (n = 40, suturing). Closure with Steri-Strips resulted in scars with comparable cosmesis as those with subcuticular suturing. Wound complications were also similar. There was no statistically significant difference between mean VAS scores on the 5th day (P = 0.320), 2nd week (P = 0.080), 4th week (P = 0.070) and 8th week (P = 0.080). The HWES scores were also comparable at those times. Conclusions: We conclude that skin closure of clean paediatric groin wounds with SteriStrips™ gives comparative cosmetic outcomes with subcuticular suturing
Impact of perioperative chemotherapy on Nigerian patients with locally advanced and metastatic gastric cancer.
Adaptation of the Wound Healing Questionnaire universal-reporter outcome measure for use in global surgery trials (TALON-1 study): mixed-methods study and Rasch analysis
BackgroundThe Bluebelle Wound Healing Questionnaire (WHQ) is a universal-reporter outcome measure developed in the UK for remote detection of surgical-site infection after abdominal surgery. This study aimed to explore cross-cultural equivalence, acceptability, and content validity of the WHQ for use across low- and middle-income countries, and to make recommendations for its adaptation.MethodsThis was a mixed-methods study within a trial (SWAT) embedded in an international randomized trial, conducted according to best practice guidelines, and co-produced with community and patient partners (TALON-1). Structured interviews and focus groups were used to gather data regarding cross-cultural, cross-contextual equivalence of the individual items and scale, and conduct a translatability assessment. Translation was completed into five languages in accordance with Mapi recommendations. Next, data from a prospective cohort (SWAT) were interpreted using Rasch analysis to explore scaling and measurement properties of the WHQ. Finally, qualitative and quantitative data were triangulated using a modified, exploratory, instrumental design model.ResultsIn the qualitative phase, 10 structured interviews and six focus groups took place with a total of 47 investigators across six countries. Themes related to comprehension, response mapping, retrieval, and judgement were identified with rich cross-cultural insights. In the quantitative phase, an exploratory Rasch model was fitted to data from 537 patients (369 excluding extremes). Owing to the number of extreme (floor) values, the overall level of power was low. The single WHQ scale satisfied tests of unidimensionality, indicating validity of the ordinal total WHQ score. There was significant overall model misfit of five items (5, 9, 14, 15, 16) and local dependency in 11 item pairs. The person separation index was estimated as 0.48 suggesting weak discrimination between classes, whereas Cronbach's α was high at 0.86. Triangulation of qualitative data with the Rasch analysis supported recommendations for cross-cultural adaptation of the WHQ items 1 (redness), 3 (clear fluid), 7 (deep wound opening), 10 (pain), 11 (fever), 15 (antibiotics), 16 (debridement), 18 (drainage), and 19 (reoperation). Changes to three item response categories (1, not at all; 2, a little; 3, a lot) were adopted for symptom items 1 to 10, and two categories (0, no; 1, yes) for item 11 (fever).ConclusionThis study made recommendations for cross-cultural adaptation of the WHQ for use in global surgical research and practice, using co-produced mixed-methods data from three continents. Translations are now available for implementation into remote wound assessment pathways