Elevated risk of pre-diabetes and diabetes in people with past history of COVID-19 in northeastern Nigeria.

BACKGROUND: An increased risk of diabetes mellitus (DM) after COVID-19 has been reported in the United States, Europe, and Asia. The burden of COVID-related DM has yet to be described in Africa, where the overall risk of DM has been increasing rapidly. Our objective was to compare the prevalence of pre-DM and DM in Nigerian individuals with a history of COVID-19 to individuals without known COVID-19 infection. METHODS: We undertook a retrospective cohort study with 256 individuals with a past medical history of COVID-19 with no history of pre-DM or DM and 256 individuals without a history of COVID-19 or pre-DM/DM. Participants were categorized as pre-DM (fasting capillary glucose 100-125 mg/dL) or DM (fasting capillary glucose ≥ 126 mg/dL). We employed univariate and multivariable logistic regression to identify key predictors and adjust for confounders related to hyperglycaemia risk factors. Additionally, we used multinomial logistic regression to analyze the relationship between COVID-19 history and diabetes status, distinguishing between normal, pre-diabetic, and diabetic glucose levels. All models were adjusted for age, gender, hypertension, physical activity, central adiposity, and family history of DM. RESULTS: Compared to the control group, those with a history of COVID-19 had a similar median age (38 vs. 40 years, p = 0.84), had a higher proportion of men (63% vs. 49%), and had a lower prevalence of central adiposity (waist: hip ratio ≥ 0.90 for males and WHR ≥ 0.85 for females) (48% vs. 56.3%, p = 0.06). Of the 256 with a history of COVID-19, 44 (17%) required in-patient care. The median (interquartile range) time interval between COVID-19 diagnosis and the glycaemic assessment was 19 (IQR: 14, 24) months. Pre-DM prevalence was 27% in the post-COVID-19 group and 4% in the control group, whereas the prevalence of DM was 7% in the post-COVID-19 group and 2% in the control group. After multivariable adjustment, the odds of pre-DM were 8.12 (95% confidence interval (CI): 3.98, 16.58; p < 0.001) higher, and the odds of DM were 3.97 (95% CI: 1.16, 13.63) higher in those with a history of COVID-19 compared to controls. In the adjusted multinomial logistic regression analysis, individuals with a history of COVID-19 exhibited significantly elevated risks for pre-diabetes (RRR = 7.55, 95% CI: 3.76-15.17) and diabetes (RRR = 3.44, 95% CI: 1.01-11.71) compared to those without COVID-19. CONCLUSION: Previous COVID-19 was found to be a risk factor for prevalent pre-diabetes and diabetes mellitus in Nigeria. More intensive screening for DM in those with a history of COVID-19 should be considered.

Efficacy and safety of pyronaridine-artesunate versus artemether-lumefantrine in the treatment of acute uncomplicated malaria in children in South-West Nigeria: an open-labelled randomized controlled trial.

BACKGROUND: In Nigeria, declining responsiveness to artemether-lumefantrine (AL), the artemisinin-based combination therapy (ACT) of choice since 2005, has been reported. Pyronaridine-artesunate (PA) is a newer fixed-dose ACT recently prequalified by the WHO for the treatment of uncomplicated falciparum malaria. However, PA data from the Nigerian pediatric population is scarce. Therefore, the efficacy and safety of PA and AL using the WHO 28-day anti-malarial therapeutic efficacy study protocol in Ibadan, southwest Nigeria, were compared. METHODS: In an open-labelled, randomized, controlled clinical trial, 172 children aged 3-144 months with a history of fever and microscopically confirmed uncomplicated Plasmodium falciparum malaria were enrolled in southwest Nigeria. Enrollees were randomly assigned to receive PA or AL at standard dosages according to body weight for 3 days. Venous blood was obtained for hematology, blood chemistry, and liver function tests on days 0, 3, 7, and 28 as part of the safety evaluation. RESULTS: 165 (95.9%) of the enrolled individuals completed the study. About half (52.3%; 90/172) of enrollees were male. Eighty-seven (50.6%) received AL, while 85 (49.4%) received PA. Day 28, adequate clinical and parasitological response for PA was 92.7% [(76/82) 95% CI 83.1, 95.9] and 71.1% [(59/83) 95% CI 60.4, 79.9] for AL (0.001). Fever and parasite clearance were similar in both groups. Two of six and eight of 24 parasite recurrences were observed among PA- and AL-treated children, respectively. PCR-corrected Day-28 cure rates for PA were 97.4% (76/78) and 88.1% (59/67) for AL (= 0.04) in the per-protocol population after new infections were censored. Hematological recovery at day 28 was significantly better among PA-treated patients (34.9% 2.8) compared to those treated with AL (33.1% 3.0) (0.002). Adverse events in both treatment arms were mild and similar to the symptoms of malaria infection. Blood chemistry and liver function tests were mostly within normal limits, with an occasional marginal rise. CONCLUSION: PA and AL were well-tolerated. PA was significantly more efficacious than AL in both the PCR-uncorrected and PCR-corrected per-protocol populations during this study. The results of this study support the inclusion of PA in the anti-malarial treatment guidelines in Nigeria. RETROSPECTIVE TRIAL REGISTRATION: Clinicaltrials.gov: NCT05192265.

Paleolimnological evaluation of metal(loid) enrichment from oil sands and gold mining operations in northwestern Canada.

Abundant reserves of metals and oil have spurred large-scale mining developments across northwestern Canada during the past 80 years. Historically, the associated emissions footprint of hazardous metal(loid)s has been difficult to identify, in part, because monitoring records are too short and sparse to have characterized their natural concentrations before mining began. Stratigraphic analysis of lake sediment cores has been employed where concerns of pollution exist to determine pre-disturbance metal(loid) concentrations and quantify the degree of enrichment since mining began. Here, we synthesize the current state of knowledge via systematic re-analysis of temporal variation in sediment metal(loid) concentrations from 51 lakes across four key regions spanning 670 km from bitumen mining in the Alberta Oil Sands Region (AOSR) to gold mining (Giant and Con mines) at Yellowknife in central Northwest Territories. Our compilation includes upland and floodplain lakes at varying distances from the mines to evaluate dispersal of pollution-indicator metal(loid)s from bitumen (vanadium and nickel) and gold mining (arsenic and antimony) via atmospheric and fluvial pathways. Results demonstrate 'severe' enrichment of vanadium and nickel at near-field sites (≤20 km) within the AOSR and 'severe' (near-field; ≤ 40 km) to 'considerable' (far-field; 40-80 km) enrichment of arsenic and antimony due to gold mining at Yellowknife via atmospheric pathways, but no evidence of enrichment of vanadium or nickel via atmospheric or fluvial pathways at the Peace-Athabasca Delta and Slave River Delta. Findings can be used by decision makers to evaluate risks associated with contaminant dispersal by the large-scale mining activities. In addition, we reflect upon methodological approaches to be considered when evaluating paleolimnological data for evidence of anthropogenic contributions to metal(loid) deposition and advocate for proactive inclusion of paleolimnology in the early design stage of environmental contaminant monitoring programs.

High prevalence of persistent residual parasitemia on days 3 and 14 after artemether-lumefantrine or pyronaridine-artesunate treatment of uncomplicated Plasmodium falciparum malaria in Nigeria.

BACKGROUND: Microscopic evaluation of parasite clearance is the gold standard in antimalarial drug efficacy trials. However, the presence of sub-microscopic residual parasitemia after artemisinin-based combination therapy (ACT) needs to be investigated. METHODS: One hundred and twenty (AL: n = 60, PA: n = 60) days 3 and 14 dried blood spots, negative by microscopy were analysed for residual parasitemia using nested PCR. Isolates with residual parasitemia on days 3 and 14 were further genotyped with their corresponding day-0 isolates using merozoite surface proteins msp-1, msp-2, and glurp genes for allelic similarity. RESULTS: Persistent PCR-determined sub-microscopic residual parasitemia at day 3 post ACT treatment was 83.3 (AL) and 88.3% (PA), respectively (ρ = 0.600), while 63.6 and 36.4% (ρ = 0.066) isolates were parasitemic at day 14 for AL and PA, respectively. Microscopy-confirmed gametocytemia persisted from days 0 to 7 and from days 0 to 21 for AL and PA. When the alleles of day 3 versus day 0 were compared according to base pair sizes, 59% of parasites shared identical alleles for glurp, 36% each for 3D7 and FC27, while K1 was 77%, RO33 64%, and MAD20 23%, respectively. Similarly, day 14 versus day 0 was 36% (glurp), 64% (3D7), and 32% (FC27), while 73% (K1), 77% (RO33), and 41% (MAD20), respectively. CONCLUSION: The occurrence of residual parasitemia on days 3 and 14 following AL or PA treatment may be attributable to the presence of either viable asexual, gametocytes, or dead parasite DNAs, which requires further investigation.

Evaluating Lower Athabasca River Sediment Metal Concentrations from Alberta Oil Sands Monitoring Programs Using Predevelopment Baselines.

Since 1997, sediment metal concentrations have been monitored in the Alberta Oil Sands Region (AOSR) of the Lower Athabasca River by the Regional Aquatics Monitoring Program (RAMP; 1997-2002), the Joint Oil Sands Monitoring Program (JOSM; 2012-2014), and the Oil Sands Monitoring Program (OSM; 2015-present). However, it has remained difficult to differentiate industrial sources from natural sources and quantify the extent of pollution due to inadequate knowledge of predevelopment reference conditions. Here, baselines were constructed using predevelopment (i.e., pre-1967) sediment concentrations of US EPA priority pollutants (Be, Cr, Cu, Ni, Pb) and V, an element elevated in bitumen and associated waste materials, normalized to Al concentration in cores from floodplain and upland lakes within the AOSR to characterize the natural range of variability. The Lower Athabasca River sediment metal monitoring data were examined in the context of the predevelopment baselines. Most metals are below the threshold for minimal enrichment (<1.5x baseline) except for chromium (up to 4.8x) in some RAMP samples. The predevelopment baselines for sediment metal concentrations will be of particular importance as the oil sands industry potentially shifts from a no-release policy to the treatment and release of oil sands process waters directly to the Lower Athabasca River.

Frequency doubling and parametric fluorescence in a four-port aluminum gallium arsenide photonic chip.

In this Letter, we report on the fabrication and characterization of a monolithic III-V semiconductor photonic chip, designed to perform nonlinear parametric optical processes for frequency conversion and non-classical state generation. This chip co-integrates an AlGaAs microdisk that is evanescently coupled to two distinct suspended waveguides designed for light injection and collection around 1600 nm and 800 nm, respectively. Quasi-phase matching provided by the resonator geometry and material symmetry, resonant field enhancement, and confinement ensure efficient nonlinear interactions. We demonstrate second-harmonic generation efficiency of 5%W-1 and a biphoton generation rate of 1.2 kHz/µW through spontaneous down-conversion.

Use of pre-industrial baselines to monitor anthropogenic enrichment of metals concentrations in recently deposited sediment of floodplain lakes in the Peace-Athabasca Delta (Alberta, Canada).

Well-designed monitoring approaches are needed to assess effects of industrial development on downstream aquatic environments and guide environmental stewardship. Here, we develop and apply a monitoring approach to detect potential enrichment of metals concentrations in surficial lake sediments of the Peace-Athabasca Delta (PAD), northern Alberta, Canada. Since the ecological integrity of the PAD is strongly tied to river floodwaters that replenish lakes in the delta, and the PAD is located downstream of the Alberta oil sands, concerns have been raised over the potential transport of industry-supplied metals to the PAD via the Athabasca River. Surface sediment samples were collected in September 2017 from 61 lakes across the delta, and again in July 2018 from 20 of the same lakes that had received river floodwaters 2 months earlier, to provide snapshots of metals concentrations (Be, Cd, Cr, Cu, Ni, Pb, V, and Zn) that have recently accumulated in these lakes. To assess for anthropogenic enrichment, surficial sediment metals concentrations were normalized to aluminum and compared to pre-industrial baseline (i.e., reference) metal-aluminum linear relations for the Athabasca and Peace sectors of the PAD developed from pre-1920 measurements in lake sediment cores. Numerical analysis demonstrates no marked enrichment of these metals concentrations above pre-1920 baselines despite strong ability (> 99% power) to detect enrichment of 10%. Measurements of river sediment collected by the Regional Aquatics- and Oil Sands-Monitoring Programs (RAMP/OSM) also did not exceed pre-1920 concentrations. Thus, results presented here show no evidence of substantial oil sands-derived metals enrichment of sediment supplied by the Athabasca River to lakes in the PAD and demonstrate the usefulness of these methods as a monitoring framework.

III-nitride on silicon electrically injected microrings for nanophotonic circuits.

Nanophotonic circuits using group III-nitrides on silicon are still lacking one key component: efficient electrical injection. In this paper we demonstrate an electrical injection scheme using a metal microbridge contact in thin III-nitride on silicon mushroom-type microrings that is compatible with integrated nanophotonic circuits with the goal of achieving electrically injected lasing. Using a central buried n-contact to bypass the insulating buffer layers, we are able to underetch the microring, which is essential for maintaining vertical confinement in a thin disk. We demonstrate direct current room-temperature electroluminescence with 440 mW/cm2 output power density at 20 mA from such microrings with diameters of 30 to 50 µm. The first steps towards achieving an integrated photonic circuit are demonstrated.

Genetic variants of tumor necrosis factor-α -308G/A (rs1800629) but not Toll-interacting proteins or vitamin D receptor genes enhances susceptibility and severity of malaria infection.

Susceptibility to malaria infection has been associated with host genetic polymorphisms that differs between groups. We hypothesize that Toll-interacting proteins (TOLLIP), vitamin D receptor (VDR) and tumor necrosis factor-α (TNF) genes are significant contributors to susceptibility and disease severity in Plasmodium falciparum (Pf) infection. Our aim is to explore the genomic diversity and haplotype frequency of these genes, as well as extrapolate possible association with markers of severity, between malaria-infected and healthy controls. Genomic DNA samples extracted from the blood of 107 malaria-infected patients and 190 uninfected controls were analyzed, with no difference in genotypic or allelic frequencies of TOLLIP and VDR polymorphisms. However, a significant difference in the genotypic (p = 2.20E-16) and allelic frequencies (p = 2.20E-16) of the TNF-α (snp rs1800629) polymorphism was found. The preponderance of the mutant variant among the malaria-infected show a possible impaired capacity to mount an effective immune response, potentially confirmed by our association results. This result calls for analysis of clearly delineated uncomplicated versus severe disease groups, including serum assays, providing a basis to conclude that susceptibility to malaria infection and potential contribution to disease severity is significantly associated with polymorphisms of the tumor necrosis factor-α but not TOLLIP or VDR genes.

Extensive diversity in the allelic frequency of Plasmodium falciparum merozoite surface proteins and glutamate-rich protein in rural and urban settings of southwestern Nigeria.

BACKGROUND: Nigeria carries a high burden of malaria which makes continuous surveillance for current information on genetic diversity imperative. In this study, the merozoite surface proteins (msp-1, msp-2) and glutamate-rich protein (glurp) of Plasmodium falciparum collected from two communities representing rural and urban settings in Ibadan, southwestern Nigeria were analysed. METHODS: A total of 511 febrile children, aged 3-59 months, whose parents/guardians provided informed consent, were recruited into the study. Capillary blood was obtained for malaria rapid diagnostic test, thick blood smears for parasite count and blood spots on filter paper for molecular analysis. RESULTS: Three-hundred and nine samples were successfully genotyped for msp-1, msp-2 and glurp genes. The allelic distribution of the three genes was not significantly different in the rural and urban communities. R033 and 3D7 were the most prevalent alleles in both rural and urban communities for msp-1 and msp-2, respectively. Eleven of glurp RII region genotypes, coded I-XII, with sizes ranging from 500 to 1100 base pairs were detected in the rural setting. Genotype XI (1000-1050 bp) had the highest prevalence of 41.5 and 38.5% in rural and urban settings, respectively. Overall, 82.1 and 70.0% of samples had multiclonal infection with msp-1 gene resulting in a mean multiplicity of infection (MOI) of 2.8 and 2.6 for rural and urban samples, respectively. Msp-1 and msp-2 genes displayed higher levels of diversity and higher MOI rates than the glurp gene. CONCLUSION: Significant genetic diversity was observed between rural and urban parasite populations in Ibadan, southwestern Nigeria. The results of this study show that malaria transmission intensity in these regions is still high. No significant difference was observed between rural and urban settings, except for a completely different msp-1 allele, compared to previous reports, thereby confirming the changing face of malaria transmission in these communities. This study provides important baseline information required for monitoring the impact of malaria elimination efforts in this region and data points useful in revising current protocols.

Directionally induced quasi-phase matching in homogeneous AlGaAs waveguides.

We report on the experimental observation of quasi-phase matching in a homogeneous waveguide. By fabricating a monolithic snake-shaped suspended AlGaAs nanowire on a (001) GaAs wafer, we demonstrate the unraveled version of a χ(2) whispering-gallery-mode microdisk, obtaining second-harmonic generation in the optical telecom wavelength range. With a radius of curvature of 50 µm and four spatial oscillations along the (110) average direction, a splitting of the second-harmonic spectrum occurs around the phase-matching wavelength of the corresponding straight waveguide. This splitting, which increases as the radius of curvature decreases, provides a useful degree of freedom for the design of small-footprint nonlinear photonic devices on-chip.

Near-infrared III-nitride-on-silicon nanophotonic platform with microdisk resonators.

We have developed a nanophotonic platform with microdisks using epitaxial III-nitride materials on silicon. The two-dimensional platform consists of suspended waveguides and mushroom-type microdisks as resonators side-coupled with a bus waveguide. Loaded quality factors up to 80000 have been obtained in the near-infrared spectral range for microdisk diameters between 8 and 15 µm. We analyze the dependence of the quality factors as a function of coupling efficiency. We have performed continuous-wave second harmonic generation experiments in resonance with the whispering gallery modes supported by the microdisks.

Characterizing baseline concentrations, proportions, and processes controlling deposition of river-transported bitumen-associated polycyclic aromatic compounds at a floodplain lake (Slave River Delta, Northwest Territories, Canada).

Inadequate knowledge of baseline conditions challenges ability for monitoring programs to detect pollution in rivers, especially where there are natural sources of contaminants. Here, we use paleolimnological data from a flood-prone lake ("SD2", informal name) in the Slave River Delta (SRD, Canada), ∼ 500 km downstream of the Alberta oil sands development and the bitumen-rich McMurray Formation to identify baseline concentrations and proportions of "river-transported bitumen-associated indicator polycyclic aromatic compounds" (indicator PACs; Hall et al. 2012) and processes responsible for their deposition. Results show that indicator PACs are deposited in SD2 by Slave River floodwaters in concentrations that are 45 % lower than those in sediments of "PAD31compounds", a lake upstream in the Athabasca Delta that receives Athabasca River floodwaters. Lower concentrations at SD2 are likely a consequence of sediment retention upstream as well as dilution by sediment influx from the Peace River. In addition, relations with organic matter content reveal that flood events dilute concentrations of indicator PACs in SD2 because the lake receives high-energy floods and the lake sediments are predominantly inorganic. This contrasts with PAD31 where floodwaters increase indicator PAC concentrations in the lake sediments, and concentrations are diluted during low flood influence intervals due to increased deposition of lacustrine organic matter. Results also show no significant differences in concentrations and proportions of indicator PACs between pre- (1967) and post- (1980s and 1990 s) oil sands development high flood influence intervals (t = 1.188, P = 0.279, d.f. = 6.136), signifying that they are delivered to the SRD by natural processes. Although we cannot assess potential changes in indicator PACs during the past decade, baseline concentrations and proportions can be used to enhance ongoing monitoring efforts.

Source Apportionment of Background PAHs in the Peace-Athabasca Delta (Alberta, Canada) Using Molecular Level Radiocarbon Analysis.

The downstream accumulation of polycyclic aromatic hydrocarbons (PAHs) in the Peace-Athabasca Delta (PAD), an ecologically important landscape, is a key issue of concern given the rapid development of the oil sands industry in Northern Alberta, Canada. In addition to PAHs derived from industrial activity (i.e., oil sands mining) within the Athabasca watershed, however, forest fires and erosion of fossil fuel deposits within both the Athabasca and Peace watersheds are two potentially important natural sources of PAHs delivered to the PAD. Consequently, evaluating the environmental impact of mining activities requires a quantitative understanding of natural, background PAHs. Here, we utilize molecular-level natural-abundance radiocarbon measurements on an amalgamated sediment record from a Peace River flood-susceptible oxbow lake in the northern Peace sector of the PAD to quantitatively discriminate sources of naturally occurring alkylated PAHs (fossil and modern biomass). A radiocarbon mass balance quantified a predominantly natural petrogenic source (93% petrogenic, 7% forest fire) for alkylated PAHs during the past ∼50 years. Additionally, a significant petrogenic component determined for retene, a compound usually considered a biomarker for softwood combustion, suggests that its use as a unique forest fire indicator may not be suitable in PAD sediments receiving Peace watershed-derived fluvial inputs.

Science-policy processes for transboundary water governance.

In this policy perspective, we outline several conditions to support effective science-policy interaction, with a particular emphasis on improving water governance in transboundary basins. Key conditions include (1) recognizing that science is a crucial but bounded input into water resource decision-making processes; (2) establishing conditions for collaboration and shared commitment among actors; (3) understanding that social or group-learning processes linked to science-policy interaction are enhanced through greater collaboration; (4) accepting that the collaborative production of knowledge about hydrological issues and associated socioeconomic change and institutional responses is essential to build legitimate decision-making processes; and (5) engaging boundary organizations and informal networks of scientists, policy makers, and civil society. We elaborate on these conditions with a diverse set of international examples drawn from a synthesis of our collective experiences in assessing the opportunities and constraints (including the role of power relations) related to governance for water in transboundary settings.

Relations between water physico-chemistry and benthic algal communities in a northern Canadian watershed: defining reference conditions using multiple descriptors of community structure.

Defining reference conditions is central to identifying environmental effects of anthropogenic activities. Using a watershed approach, we quantified reference conditions for benthic algal communities and their relations to physico-chemical conditions in rivers in the South Nahanni River watershed, NWT, Canada, in 2008 and 2009. We also compared the ability of three descriptors that vary in terms of analytical costs to define algal community structure based on relative abundances of (i) all algal taxa, (ii) only diatom taxa, and (iii) photosynthetic pigments. Ordination analyses showed that variance in algal community structure was strongly related to gradients in environmental variables describing water physico-chemistry, stream habitats, and sub-watershed structure. Water physico-chemistry and local watershed-scale descriptors differed significantly between algal communities from sites in the Selwyn Mountain ecoregion compared to sites in the Nahanni-Hyland ecoregions. Distinct differences in algal community types between ecoregions were apparent irrespective of whether algal community structure was defined using all algal taxa, diatom taxa, or photosynthetic pigments. Two algal community types were highly predictable using environmental variables, a core consideration in the development of Reference Condition Approach (RCA) models. These results suggest that assessments of environmental impacts could be completed using RCA models for each ecoregion. We suggest that use of algal pigments, a high through-put analysis, is a promising alternative compared to more labor-intensive and costly taxonomic approaches for defining algal community structure.

DETERMINANTS OF SPECIALTY CHOICE OF RESIDENT DOCTORS; CASE STUDY--AMONG RESIDENT DOCTORS IN NIGERIA.

OBJECTIVE: This study examined medical specialty selection by Nigerian resident doctors using a marketing research approach to determine the selection criteria and the role of perceptions, expected remuneration, and job placement prospects of various specialties in the selection process. METHODS: Data were from the Community of residents from April 2014 to July 2014. The cohort included 200 residents, but only 171 had complete information. Data were obtained from a cross section of resident doctors in the Lagos State University Teaching Hospital and at the 2014 Ordinary General Meeting of the National Association of Resident Doctors(NARD) where representatives from over 50 Teaching hospitals in Nigeria attended. Using a client behaviour model as a framework, a tripartite questionnaire was designed and administered to residents to deduce information on their knowledge about and interests in various specialties, their opinions of sixteen specialties, and the criteria they used in specialty selection. RESULTS: A total of 171 (85.5%) questionnaires were returned. ln many instances, consistency between selection criteria and perceptions of a specialty were accompanied by interest in pursuing the specialty. Job security, job availability on completion of programme, duration of training and qualifying examinations were highly correlated with p value < 0.05. Results of the Principal Component Analysis show two components (with Eigen values greater than one) explaining 65.3% of the total variance. The first component had placement and training and practice related variables loaded on it while the second component was loaded with job security and financial remuneration related variables. CONCLUSIONS: Using marketing research concepts for medical specialty selection (Weissmanet al 2012) stipulates that choice of speciality is influenced by criteria and perception. This study shows that job security expected financial remuneration, and examination requirements for qualification are major determinants of the choice of speciality for residents.

Child pedestrian injury and fatality in a developing country.

PURPOSE: Child pedestrian injuries and fatalities in developing countries continue to increase. We examined child pedestrian injuries and fatalities in the most populated urban agglomeration in Africa in order to develop control measures. METHODS: Two-year prospective study of injured child pedestrians (≤15 years) at the Surgical Emergency Room (SER) to determine demography, vehicles involved, road location, injury mechanism, pre-hospital transport, injury-arrival time, regions injured, injury severity and fatalities was done. RESULTS: Some 226 pedestrians (114 boys and 112 girls) comprising 42 children aged ≤4 years, 91 aged 5-9 years and 93 aged 10-15 years were seen with car collisions (83 pedestrians, 36.7%), motorcycles (76, 33.6%), buses (41, 18.1%), others (15, 6.6%) and 11 undetermined vehicles. Injuries on the highways were 147 (65%); inner-city roads 77 (34.1%) and two undetermined roads. Crossing the road was responsible for 168 (74.3%) pedestrian injuries; while three other mechanisms produced 58 (25.7%) patients. Regions injured were head (42.9%), lower limbs (35.4%) and others (21.7%). Relatives, bystanders and police/ambulance brought 186 (82.3%), 31 (13.7%) and eight (3.5%) children, respectively; and within 6 h (43.4, 11.5 and 2.2%) and after (38.9, 2.2 and 1.3%). Nineteen deaths (10 brought-in-dead, nine SER deaths) occurred; 15 of them girls, 15 had severe head injury, 15 were brought by relatives. However, fatality risks were truck collisions (OR 5.97), female child (OR 4.25), head injury (OR 4.18) and age ≤4 years (OR 3.7). CONCLUSION: The equal sex incidence, worse female fatality despite similar exposure and injury severity with male, deserve further research. Improved pre-hospital and SER care is needed.

A novel model for predicting the productivity index of horizontal/vertical wells based on Darcy's law, drainage radius, and flow convergence.

The Productivity Index (PI) of oil wells is essential to developing a field's production plan, and previous studies report different models for predicting the PI of horizontal or vertical wells. However, predicting the PI of horizontal and vertical wells using a single cost-effective model remains unaccomplished. The models only predict results for either box-shaped or circular reservoirs. Thus, this study reports a new model for predicting the PI of horizontal and vertical wells in any reservoir type. The model incorporates the length of the horizontal section and formation thickness to Darcy's equation, and forms empirically the external drainage radius using vertical and horizontal radii. It includes both geometric pseudoskin (accounting for fluid convergence) and empirically determined correction parameters. The derived PI is validated using data from box-shaped and circular reservoirs, and the results showed that changes in permeability, well length, or well radius affect the PI for both reservoir types. In addition, the drainage radius of the horizontal well increased non-linearly with the PI. Sensitivity analyses of 20,000 runs and 20,000 trials, carried out with the Crystal Ball software, showed that the viscosity and formation volume factor were the most important variables that affected the PI, for both reservoir types.

Creating a novel method for chicken primordial germ cell health monitoring using the fluorescent ubiquitination-based cell cycle indicator reporter system.

The most current in vitro genetic methods, including gene preservation, gene editing and developmental modelling, require a significant number of healthy cells. In poultry species, primordial germ cells (PGCs) are great candidates for all the above-mentioned purposes, given their easy culturing and well-established freezing method for chicken. However, the constant monitoring of cultures can be financially challenging and consumes large amounts of solutions and accessories. This study aimed to introduce the Fluorescent Ubiquitination-based Cell Cycle Indicator (FUCCI) complex into the chicken PGCs. FUCCI is a powerful transgenic tool based on the periodic protein expression changes during the cell cycle. It includes chromatin licensing and DNA replication factor 1 attached monomeric Kusabira-Orange and Geminin-attached monomeric Azami-Green fluorescent proteins, that cause the cells to express a red signal in the G1 phase and a green signal in S and G2 phases. Modification of the chicken PGCs was done via electroporation and deemed to be successful according to confocal microscopy, DNA sequencing and timelapse video analysis. Stable clone cell lines were established, cryopreserved, and injected into recipient embryos to prove the integrational competency. The cell health monitoring was tested with medium change experiments, that proved the intended reactions of the FUCCI transgene. These results established the future for FUCCI experiments in chicken, including heat treatment and toxin treatment.