Analysis of Artificial Lighting Design Fixture on the Indoor Night Time Illuminance

Human beings depend on a lighting system in their indoor environment for visual tasks and to function appropriately. With daylight absent during the night, artificial lighting becomes the only lighting source for illuminance. This study evaluated the effect of lighting design fixtures on the artificial lighting illuminance adequacy of students’ private rooms. The illuminance level was measured using the Sunche model HS1010 digital luxmeter with a sampling frequency of 2 times per second and a high precision wide measurement range of 1 - 1200,000 lux at nine (9) grid points. Analysis of illuminance data obtained showed that the lamp capacities (5, 10, 50, 100, and 200 Watts) and the lighting fixtures array (single light point source (centred), double (opposite array) and quadruple (double opposite layout)) affect the adequacy of the indoor space illuminance. The wall paint colour (cream, pink and blue) did not affect the reflection ability of the illuminance as they were all emulsion paints. Analysis of the side effect of the lighting design fixtures showed that the lamp capacities, the lighting fixtures design, and the wall paint colour did not affect the thermal conditions of the indoor environment. Therefore, this study concluded that the higher the lamp capacities and the lighting fixtures array the better the nighttime artificial illuminance

Calibration of arterial spin labeling data—potential pitfalls in post‐processing

PurposeTo assess the impact of the different post‐processing options in the calibration of arterial spin labeling (ASL) data on perfusion quantification and its reproducibility.Theory and MethodsAbsolute quantification of perfusion measurements is one of the promises of ASL techniques. However, it is highly dependent on a calibration procedure that involves a complex processing pipeline for which no standardized procedure has been fully established. In this work, we systematically compare the main ASL calibration methods as well as various post‐processing calibration options, using 2 data sets acquired with the most common sequences, pulsed ASL and pseudo‐continuous ASL.ResultsSignificant and sometimes large discrepancies in ASL perfusion quantification were obtained when using different post‐processing calibration options. Nevertheless, when using a set of theoretically based and carefully chosen options, only small differences were observed for both reference tissue and voxelwise methods. The voxelwise and white matter reference tissue methods were less sensitive to post‐processing options than the cerebrospinal fluid reference tissue method. However, white matter reference tissue calibration also produced poorer reproducibility results. Moreover, it may also not be an appropriate reference in case of white matter pathology.ConclusionPoor post‐processing calibration options can lead to large errors in perfusion quantification, and a complete description of the calibration procedure should therefore be reported in ASL studies. Overall, our results further support the voxelwise calibration method proposed by the ASL white paper, particularly given the advantage of being relatively simple to implement and intrinsically correcting for the coil sensitivity profile

A systematic study of the sensitivity of partial volume correction methods for the quantification of perfusion from pseudo-continuous arterial spin labeling MRI

Arterial spin labeling (ASL) MRI is a non-invasive technique for the quantification of cerebral perfusion, and pseudo-continuous arterial spin labeling (PCASL) has been recommended as the standard implementation by a recent consensus of the community. Due to the low spatial resolution of ASL images, perfusion quantification is biased by partial volume effects. Consequently, several partial volume correction (PVEc) methods have been developed to reduce the bias in gray matter (GM) perfusion quantification. The efficacy of these methods relies on both the quality of the ASL data and the accuracy of partial volume estimates. Here we systematically investigate the sensitivity of different PVEc methods to variability in both the ASL data and partial volume estimates using simulated PCASL data and in vivo PCASL data from a reproducibility study. We examined the PVEc methods in two ways: the ability to preserve spatial details and the accuracy of GM perfusion estimation. Judging by the root-mean-square error (RMSE) between simulated and estimated GM CBF, the spatially regularized method was superior in preserving spatial details compared to the linear regression method (RMSE of 1.2 vs 5.1 in simulation of GM CBF with short scale spatial variations). The linear regression method was generally less sensitive than the spatially regularized method to noise in data and errors in the partial volume estimates (RMSE 6.3 vs 23.4 for SNR = 5 simulated data), but this could be attributed to the greater smoothing introduced by the method. Analysis of a healthy cohort dataset indicates that PVEc, using either method, improves the repeatability of perfusion quantification (within-subject coefficient of variation reduced by 5% after PVEc)

What are the drivers of recurrent cholera transmission in Nigeria? Evidence from a scoping review

Background: The 2018 cholera outbreak in Nigeria affected over half of the states in the country, and was characterised by high attack and case fatality rates. The country continues to record cholera cases and related deaths to date. However, there is a dearth of evidence on context-specific drivers and their operational mechanisms in mediating recurrent cholera transmission in Nigeria. This study therefore aimed to fill this important research gap, with a view to informing the design and implementation of appropriate preventive and control measures. / Methods: Four bibliographic literature sources (CINAHL (Plus with full text), Web of Science, Google Scholar and PubMed), and one journal (African Journals Online) were searched to retrieve documents relating to cholera transmission in Nigeria. Titles and abstracts of the identified documents were screened according to a predefined study protocol. Data extraction and bibliometric analysis of all eligible documents were conducted, which was followed by thematic and systematic analyses. / Results: Forty-five documents met the inclusion criteria and were included in the final analysis. The majority of the documents were peer-reviewed journal articles (89%) and conducted predominantly in the context of cholera epidemics (64%). The narrative analysis indicates that social, biological, environmental and climatic, health systems, and a combination of two or more factors appear to drive cholera transmission in Nigeria. Regarding operational dynamics, a substantial number of the identified drivers appear to be functionally interdependent of each other. / Conclusion: The drivers of recurring cholera transmission in Nigeria are diverse but functionally interdependent; thus, underlining the importance of adopting a multi-sectoral approach for cholera prevention and control

Descriptive epidemiology of cholera outbreak in Nigeria, January-November, 2018: implications for the global roadmap strategy

Background: The cholera outbreak in 2018 in Nigeria reaffirms its public health threat to the country. Evidence on the current epidemiology of cholera required for the design and implementation of appropriate interventions towards attaining the global roadmap strategic goals for cholera elimination however seems lacking. Thus, this study aimed at addressing this gap by describing the epidemiology of the 2018 cholera outbreak in Nigeria. Methods: This was a retrospective analysis of surveillance data collected between January 1st and November 19th, 2018. A cholera case was defined as an individual aged 2 years or older presenting with acute watery diarrhoea and severe dehydration or dying from acute watery diarrhoea. Descriptive analyses were performed and presented with respect to person, time and place using appropriate statistics. Results: There were 43,996 cholera cases and 836 cholera deaths across 20 states in Nigeria during the outbreak period, with an attack rate (AR) of 127.43/100,000 population and a case fatality rate (CFR) of 1.90%. Individuals aged 15 years or older (47.76%) were the most affected age group, but the proportion of affected males and females was about the same (49.00 and 51.00% respectively). The outbreak was characterised by four distinct epidemic waves, with higher number of deaths recorded in the third and fourth waves. States from the north-west and north-east regions of the country recorded the highest ARs while those from the north-central recorded the highest CFRs. Conclusion: The severity and wide-geographical distribution of cholera cases and deaths during the 2018 outbreak are indicative of an elevated burden, which was more notable in the northern region of the country. Overall, the findings reaffirm the strategic role of a multi-sectoral approach in the design and implementation of public health interventions aimed at preventing and controlling cholera in Nigeri

Interventions for acute stroke management in Africa: a systematic review of the evidence

Abstract Background The past decades have witnessed a rapid evolution of research on evidence-based acute stroke care interventions worldwide. Nonetheless, the evidence-to-practice gap in acute stroke care remains variable with slow and inconsistent uptake in low-middle income countries (LMICs). This review aims to identify and compare evidence-based acute stroke management interventions with alternative care on overall patient mortality and morbidity outcomes, functional independence, and length of hospital stay across Africa. Methods This review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. An electronic search was conducted in six databases comprising MEDLINE, Embase, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Web of Science, Academic Search Complete and Cochrane Library for experimental and non-experimental studies. Eligible studies were abstracted into evidence tables and their methodological quality appraised using the Joanna Briggs Institute checklist. Data were analysed and presented narratively with reference to observed differences in patient outcomes, reporting p values and confidence intervals for any possible relationship. Results Initially, 1896 articles were identified and 37 fully screened. Four non-experimental studies (three cohort and one case series studies) were included in the final review. One study focused on the clinical efficacy of a stroke unit whilst the remaining three reported on thrombolytic therapy. The results demonstrated a reduction in patient deaths attributed to stroke unit care and thrombolytic therapy. Thrombolytic therapy was also associated with reductions in symptomatic intracerebral haemorrhage (SICH). However, the limited eligible studies and methodological limitations compromised definitive conclusions on the extent of and level of efficacy of evidence-based acute stroke care interventions across Africa. Conclusion Evidence from this review confirms the widespread assertion of low applicability and uptake of evidence-based acute stroke care in LMICs. Despite the limited eligible studies, the overall positive patient outcomes following such interventions demonstrate the applicability and value of evidence-based acute stroke care interventions in Africa. Health policy attention is thus required to ensure widespread applicability of such interventions for improved patients’ outcomes. The review findings also emphasises the need for further research to unravel the reasons for low uptake. Systematic review registration PROSPERO CRD4201605156

Estimating the burden of selected non-communicable diseases in Africa: a systematic review of the evidence

Background The burden of non-communicable diseases (NCDs) is rapidly increasing globally, and particularly in Africa, where the health focus, until recently, has been on infectious diseases. The response to this growing burden of NCDs in Africa has been affected owing to a poor understanding of the burden of NCDs, and the relative lack of data and low level of research on NCDs in the continent. Recent estimates on the burden of NCDs in Africa have been mostly derived from modelling based on data from other countries imputed into African countries, and not usually based on data originating from Africa itself. In instances where few data were available, estimates have been characterized by extrapolation and over-modelling of the scarce data. It is therefore believed that underestimation of NCDs burden in many parts of Africa cannot be unexpected. With a gradual increase in average life expectancy across Africa, the region now experiencing the fastest rate of urbanization globally, and an increase adoption of unhealthy lifestyles, the burden of NCDs is expected to rise. This thesis will, therefore, be focussing on understanding the prevalence, and/or where there are available data, the incidence, of four major NCDs in Africa, which have contributed highly to the burden of NCDs, not only in Africa, but also globally. Methods I conducted a systematic search of the literature on three main databases (Medline, EMBASE and Global Health) for epidemiological studies on NCDs conducted in Africa. I retained and extracted data from original population-based (cohort or cross sectional), and/or health service records (hospital or registry-based studies) on prevalence and/or incidence rates of four major NCDs in Africa. These include: cardiovascular diseases (hypertension and stroke), diabetes, major cancer types (cervical, breast, prostate, ovary, oesophagus, bladder, Kaposi, liver, stomach, colorectal, lung and non-Hodgkin lymphoma), and chronic respiratory diseases (chronic obstructive pulmonary disease (COPD) and asthma). From extracted crude prevalence and incidence rates, a random effect meta-analysis was conducted and reported for each NCD. An epidemiological model was applied on all extracted data points. The fitted curve explaining the largest proportion of variance (best fit) from the model was further applied. The equation generated from the fitted curve was used to determine the prevalence and cases of the specific NCD in Africa at midpoints of the United Nations (UN) population 5-year age-group population estimates for Africa. Results From the literature search, studies on hypertension had the highest publication output at 7680, 92 of which were selected, spreading across 31 African countries. Cancer had 9762 publications and 39 were selected across 20 countries; diabetes had 3701 publications and 48 were selected across 28 countries; stroke had 1227 publications and 19 were selected across 10 countries; asthma had 790 publications and 45 were selected across 24 countries; and COPD had the lowest output with 243 publications and 13 were selected across 8 countries. From studies reporting prevalence rates, hypertension, with a total sample size of 197734, accounted for 130.2 million cases and a prevalence of 25.9% (23.5, 34.0) in Africa in 2010. This is followed by asthma, with a sample size of 187904, accounting for 58.2 million cases and a prevalence of 6.6% (2.4, 7.9); COPD, with a sample size of 24747, accounting for 26.3 million cases and a prevalence of 13.4% (9.4, 22.1); diabetes, with a sample size of 102517, accounting for 24.5 million cases and a prevalence of 4.0% (2.7, 6.4); and stroke, with a sample size of about 6.3 million, accounting for 1.94 million cases and a prevalence of 317.3 per 100000 population (314.0, 748.2). From studies reporting incidence rates, stroke accounted for 496 thousand new cases in Africa in 2010, with a prevalence of 81.3 per 100000 person years (13.2, 94.9). For the 12 cancer types reviewed, a total of 775 thousand new cases were estimated in Africa in 2010 from registry-based data covering a total population of about 33 million. Among women, cervical cancer and breast cancer had 129 thousand and 81 thousand new cases, with incidence rates of 28.2 (22.1, 34.3) and 17.7 (13.0, 22.4) per 100000 person years, respectively. Among men, prostate cancer and Kaposi sarcoma closely follows with 75 thousand and 74 thousand new cases, with incidence rates of 14.5 (10.9, 18.0) and 14.3 (11.9, 16.7) per 100000 person years, respectively. Conclusion This study suggests the prevalence rates of the four major NCDs reviewed (cardiovascular diseases (hypertension and stroke), diabetes, major cancer types, and chronic respiratory diseases (COPD and asthma) in Africa are high relative to global estimates. Due to the lack of data on many NCDs across the continent, there are still doubts on the true prevalence of these diseases relative to the current African population. There is need for improvement in health information system and overall data management, especially at country level in Africa. Governments of African nations, international organizations, experts and other stakeholders need to invest more on NCDs research, particularly mortality, risk factors, and health determinants to have evidenced-based facts on the drivers of this epidemic in the continent, and prompt better, effective and overall public health response to NCDs in Africa

Subdural Empyema: Clinical Presentations and Management Options for an Uncommon Neurosurgical Emergency in a Developing Country

Background: Controversy regarding the best management strategy for subdural empyema (SDE) attests to the persisting poor outcomes for this uncommon life threatening intracranial suppurative process. Late presentation confounds the problem in developed countries. While craniotomy is commonly recommended, it is not always possible in late presentation with advanced morbidity. The aim of this study was to identify the pattern of clinical presentation and explore the outcomes following management of SDE using burr hole, aspiration, and drainage (BAAD) in resource poor settings. Materials and Methods: This is a retrospective review of prospectively collected data of 18 patients presenting with SDE over a period of 10 years from two neurosurgical centers. Data was abstracted on patients’ demographic characteristics, sources of SDE, clinical presentation and site of infection, methods of diagnosis, organisms isolated, treatments received, and outcome. Collected data was entered into the Statistical Package for the Social Sciences version 17 software and subjected to descriptive analysis for all variables. Results: Majority of the patients presented late with Glasgow Coma Scale score GCS of 9/15. Altered sensorium was noted in 14 (77.8%) of the patients, 11 (61.1%) out of the 14 patients had ≤ grade 3 of Bannister and Williams level of consciousness. The mainstay of treatment for all patients was BAAD of abscess and administration of appropriate antibiotics. Fourteen patients (77.8%) were discharged on grade A of H.W. Mauser’s grading system. Three mortalities were recorded only in patients who had grade 4 Bannister and Williams grading.Conclusion: BAAD is the near approximated option to standard craniotomy management in a limited resource facility and it has a very good clinical outcome. However, more studies are required to draw the final conclusion.Keywords: Burr hole, drainage, outcome, presentation, SD

Subdural empyema: Clinical presentations and management options for an uncommon neurosurgical emergency in a developing country

Background: Controversy regarding the best management strategy for subdural empyema (SDE) attests to the persisting poor outcomes for this uncommon life threatening intracranial suppurative process. Late presentation confounds the problem in developed countries. While craniotomy is commonly recommended, it is not always possible in late presentation with advanced morbidity. The aim of this study was to identify the pattern of clinical presentation and explore the outcomes following management of SDE using burr hole, aspiration, and drainage (BAAD) in resource poor settings.Materials and Methods: This is a retrospective review of prospectively collected data of 18 patients presenting with SDE over a period of 10 years from two neurosurgical centers. Data was abstracted on patients’ demographic characteristics, sources of SDE, clinical  presentation and site of infection, methods of diagnosis, organisms isolated, treatments received, and outcome. Collected data was entered into the Statistical Package for the Social Sciences version 17 software and subjected to descriptive analysis for all variables.Results: Majority of the patients presented late with Glasgow Coma Scale score GCS of 9/15. Altered sensorium was noted in 14 (77.8%) of the patients, 11 (61.1%) out of the 14 patients had ≤ grade 3 of Bannister and Williams level of consciousness. The mainstay of treatment for all patients was BAAD of abscess and administration of appropriate antibiotics. Fourteen patients (77.8%) were discharged on grade A of H.W. Mauser’s grading system. Three mortalities were recorded only in patients who had grade 4 Bannister and Williams grading.Conclusion: BAAD is the near approximated option to standard craniotomy management in a limited resource facility and it has a very good clinical outcome. However, more studies are required to draw the final conclusion. Keywords: Burr hole, drainage, outcome, presentation, SDE

Pattern of Presentation and Surgical Management of Spine Tumors in Southeast Nigeria over a 10‑Year Period

Background: Spine tumors could affect the bony elements and/or its neural contents. Clinical manifestations are underlined by their biological behaviors. Aim: This study aims to identify the pattern of presentation and surgical management of spine tumors in southeast Nigeria over a 10-year period. Patients and Methods: A retrospective analysis of patients who were managed surgically for the spine and spinal cord neoplastic lesions over a 10-year period. All patients had pre-and post-operative magnetic resonance imaging (MRI) and histological diagnosis. Relevant clinical, radiological, and histological data were extracted and analyzed using Statistical Package for the Social Sciences (SPSS) for windows version 21. Results: Four hundred and seventy-two spine procedures performed within the study period, 39 cases of histologically proven primary spinal cord tumors (PSCT) and non-PSCT were identified. These represented 8.3% of spine procedures. Seventeen were PSCT (3.6% of spine procedures), while 22 (4.7%) had non-PSCT, mean age for the PSCT group was 45 yrs and non-PSCT 59.5 years. A total of 56.5% of tumors are involved in the thoracic region, 43.7% in the cervical region. PSCT was likely to affect the cervical spine; while bony spine tumors, thoracic spine [odds ratio (OR) 4.9, P value 0.019]. A total of 84.6% of non-PSCT affected the bony spine, mainly the vertebral body. The histological result showed metastatic adenocarcinoma to be the most common tumor (33.3%). PSCT was likely to be benign than non-PSCT (P value < 0.00001). Gross total resection (GTR) was done in 100% of PSCT, and 50% in non-PSCT. Thirteen (40.6%) patients improved and 11 (34.4%) patients remained the same. Conclusions: Metastatic adenocarcinoma was the most common tumor of the spine. There was restricted ability at a GTR for non-PSCT compared to PSCT. Grossly 75% had improved/same neurological status, as such adjudged as a good outcome