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Microexplosion behavior of water in biodiesel emulsion droplets was studied by suspending a single droplet on a wire type thermocouple. Water in biodiesel emulsion droplets with 9%, 12%, 15%, and 18% water by volume was observed in the Leiden frost regime using a hot plate as the heat source maintained at two different temperatures of 400 °C and 500 °C. The evolution of microexplosion was recorded with a high-speed camera synchronized with a temperature data logger. The emulsions were prepared by an electrical stirrer fitted with customized made blades rotating at 1500 rpm for 15 min. The emulsions were stabilized with two different hydrophilic–lipophilic balance (HLB) values, which were prepared by mixing two different commercial surfactants. It is found that the microexplosion time and temperature were influenced by emulsion stability, water content, surfactant dosage, base plate temperature, and HLB value. All the unstable emulsions developed microexplosion at both plate temperatures. Emulsions stabilized with an HLB value of 6.31 and 18% water content did exhibit microexplosion at both base plate temperatures. Also, the waiting time was found to decrease with increasing surfactant concentrations for a 500 °C plate temperature compared to 400 °C. [ABSTRACT FROM AUTHOR]

Water-in-diesel emulsion (WiDE) is an alternative fuel for CI engines that can be employed with the existing engine setup with no additional engine retrofitting. It has benefits of simultaneous reduction of both NOx and particulate matters in addition to its impact in the combustion efficiency improvement, although this needs further investigation. This reviewpaper addresses the type of emulsion, the microexplosion phenomenon, emulsion stability and physiochemical improvement, and effect of water content on the combustion and emissions of WiDE fuel.The review also covers the recent experimentalmethodologies used in the investigation of WiDE for both transport and stationary engine applications. In this review, the fuel injection pump and spray nozzle arrangement has been found to be the most critical components as far as the secondary atomization is concerned and further investigation of the effect of these components in the microexplosion of the emulsion is suggested to be center of focus. [ABSTRACT FROM AUTHOR]

Wireless body area network (WBAN) is a promising candidate for future health monitoring system. Nevertheless, the path to mature solutions is still facing a lot of challenges that need to be overcome. Energy efficient scheduling is one of these challenges given the scarcity of available energy of biosensors and the lack of portability. Therefore, researchers from academia, industry and health sectors are working together to realize practical solutions for these challenges. The main difficulty in WBAN is the uncertainty in the state of the monitored system. Intelligent learning approaches such as a Markov Decision Process (MDP) were proposed to tackle this issue. A Markov Decision Process (MDP) is a form of Markov Chain in which the transition matrix depends on the action taken by the decision maker (agent) at each time step. The agent receives a reward, which depends on the action and the state. The goal is to find a function, called a policy, which specifies which action to take in each state, so as to maximize some utility functions (e.g., the mean or expected discounted sum) of the sequence of rewards. A partially Observable Markov Decision Processes (POMDP) is a generalization of Markov decision processes that allows for the incomplete information regarding the state of the system. In this case, the state is not visible to the agent. This has many applications in operations research and artificial intelligence. Due to incomplete knowledge of the system, this uncertainty makes formulating and solving POMDP models mathematically complex and computationally expensive. Limited progress has been made in terms of applying POMPD to real applications. In this paper, we surveyed the existing methods and algorithms for solving POMDP in the general domain and in particular in Wireless body area network (WBAN). In addition, the papers discussed recent real implementation of POMDP on practical problems of WBAN. We believe that this work will provide valuable insights for the newcomers who would like to pursue related research in the domain of WBAN. [ABSTRACT FROM AUTHOR]

Background: Hepatitis B virus (HBV) and neonatal tetanus infections remain endemic in Nigeria despite the availability of safe, effective vaccines. We aimed to determine health facilities' capacity for hepatitis B vaccine birth dose (HepB-BD) and maternal tetanus-diphtheria (Td) vaccination and to assess knowledge, attitudes, and practices of HepB-BD and maternal Td vaccine administration among health facility staff in Nigeria., Materials and Methods: This was a cross-sectional study assessing public primary and secondary health facilities in Adamawa and Enugu States. A multistage sampling approach was used to select 40 facilities and 79 health-care workers (HCWs) from each state. A structured facility assessment tool and standardized questionnaire evaluated facility characteristics and HCW knowledge, attitudes, and practices related to HepB-BD and maternal Td vaccination. Frequencies and proportions were reported as descriptive statistics., Results: The survey of 80 facilities revealed that 73.8% implemented HepB-BD and maternal Td vaccination policies. HepB-BD was administered within 24 h of birth at 61.3% of facilities and at all times at 57.5%. However, administration seldom occurred in labor and delivery (35%) or maternity wards (16.3%). Nearly half of the facilities (46.3%) had HCWs believing there were contraindications to HepB-BD vaccination. Among 158 HCWs, 26.5% believed tetanus could be transmitted through unprotected sex, prevented by vaccination at birth (46.1%), or by avoiding sharing food and utensils. 65% of HCWs knew HBV infection had the worst outcome for newborns., Conclusions: The limited implementation of national policies on HepB-BD and maternal Td vaccination, coupled with knowledge gaps among HCWs, pose significant challenges to timely vaccination, necessitating interventions to address these gaps., (Copyright © 2024 Copyright: © 2024 Annals of African Medicine.)

Introduction: rubella poses a significant public health threat, particularly in developing countries, where congenital rubella remains a preventable concern. This cross-sectional study examined rubella seroprevalence among children aged 10 and under from May to September 2016 in Jos, Nigeria., Methods: using a multistage sampling method, eligible participants who had not been vaccinated against the rubella virus and consented to participate in the study were recruited across schools in the city. Rubella-specific IgG and IgM antibodies were detected from eluted serum collected from the participants using the enzyme-linked immunosorbent assay (ELISA). Data analysis and visualization was done using the R software version 4.3.1., Results: of the 405 participants investigated in this study, 336 (82.96%) tested positive for rubella IgG, while 9 (2.22%) tested positive for rubella IgM. Factors such as age ≥ 5 years and lack of Western education showed significant associations with rubella seropositivity., Conclusion: this study highlights the seroprevalence of rubella IgG and IgM antibodies among children aged 10 and under in Jos, Nigeria. The significant associations between rubella seropositivity and factors such as age ≥ 5 years and lack of Western education underscore the necessity for an effective rubella vaccination program to prevent congenital rubella syndrome (CRS)., Competing Interests: The authors declare no competing interests., (Copyright: Hyelshilni Samuel Waziri et al.)

Context: Coronavirus disease 2019 (COVID-19) is the greatest global health catastrophe of the century, with its vaccine hesitancy compounding the woes. Relevant stakeholders, including pharmacy students (whose education was disrupted) are important bulwarks against these catastrophes, but their COVID-19-related information are scarce., Aims: We assessed COVID-19 knowledge, its vaccine uptake intentions, and the influence of personality traits among pharmacy undergraduates in a Nigerian university., Settings and Design: This was a post-lockdown cross sectional study conducted at the Faculty of Pharmaceutical Sciences, Usmanu Danfodiyo University, Sokoto., Subjects and Methods: A 61-item questionnaire was used to collect data among pharmacy undergraduates who attended Usmanu Danfodiyo University, Sokoto, Nigeria, in May 2021., Statistical Analysis Used: Summary statistics- mean (±standard deviation), range, frequency, proportion; inferential statistics- Chi square statistics, binary logistic regression., Results: The response rate was 88% (168/191). The average COVID-19 knowledge score, the frequency of acceptance, and hesitancy to take COVID-19 vaccine among study participants were 42.9% (95% confidence interval [CI] = 42.1-43.7), 39.1% (95% CI = 37.3%-41.8%), and 61.9% (95% CI = 58.0%-64.2%), respectively. In addition, of the 168 study participants, 73 (43.5%) considered themselves to have high self-esteem, 67 (39.9%) were highly extroverted, 91 (54.2%) highly privately self-conscious, 96 (57.1%) highly publicly self-conscious, and 60 (35.7%) highly self-restrained, with 57 (34.0%) not believing in the existence of COVID-19. COVID-19 knowledge varied significantly by level of study ( F [2,165] = 5.539; P = 0.005; η 2 = 0.06). Similarly, those with high self-esteem were twice as knowledgeable regarding COVID-19 as those with low self-esteem (odds ratio [OR]: 2.02; 95% CI: 1.08-3.78; P = 0.03) with gleaning COVID-19-related information from social media platforms predicting COVID-19 vaccine hesitancy (CVH) (OR: 0.37; 95% CI: 0.16-0.85; P = 0.02)., Conclusions: The observed suboptimal COVID-19 knowledge was associated with participants' low level of self-esteem, and the prevalent CVH was associated with obtaining COVID-19-related information from social media platform., (Copyright © 2024 Copyright: © 2024 Annals of African Medicine.)

Nigeria is estimated to have the largest number of children worldwide, living with chronic hepatitis B virus (HBV) infection, the leading cause of liver cancer. Up to 90% of children infected at birth develop chronic HBV infection. A birth dose of the hepatitis B vaccine (HepB-BD) followed by at least two additional vaccine doses is recommended for prevention. This study assessed barriers and facilitators of HepB-BD administration and uptake, using structured interviews with healthcare providers and pregnant women in Adamawa and Enugu States, Nigeria. The Consolidated Framework for Implementation Sciences Research (CFIR) guided data collection and analysis. We interviewed 87 key informants (40 healthcare providers and 47 pregnant women) and created a codebook for data analysis. Codes were developed by reviewing the literature and reading a subsample of queries line-by-line. The overarching themes identified as barriers among healthcare providers were: the lack of hepatitis B knowledge, limited availability of HepB-BD to vaccination days only, misconceptions about HepB-BD vaccination, challenges in health facility staffing capacity, costs associated with vaccine transportation, and concerns related to vaccine wastage. Facilitators of timely HepB-BD vaccination included: vaccine availability, storage, and hospital births occurring during immunization days. Overarching themes identified as barriers among pregnant women were lack of hepatitis B knowledge, limited understanding of HepB-BD importance, and limited access to vaccines for births occurring outside of a health facility. Facilitators were high vaccine acceptance and willingness for their infants to receive HepB-BD if recommended by providers. Findings indicate the need for enhanced HepB-BD vaccination training for HCWs, educating pregnant women on HBV and the importance of timely HepB-BD, updating policies to enable HepB-BD administration within 24 hours of birth, expanding HepB-BD availability in public and private hospital maternity wards for all facility births, and outreach activities to reach home births., Competing Interests: The authors have declared that no competing interests exist., (Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.)

Empedobacter falsenii is an emerging opportunistic pathogen that has been occasionally implicated in various human infections. In this study, we described the genomic features of a multidrug resistant E. falsenii Q1655 obtained from a patient attending a public hospital in Sokoto, northwest Nigeria. The isolate, E. falsenii Q1655, was isolated from the stool sample of a patient in Sokoto, Nigeria. The identity of the isolate was confirmed by MALDITOF-MS. The disc diffusion test and modified Carba-NP test were used for phenotypic antibiotic susceptibility test and carbapenemase enzyme production test, respectively. The whole genome of the strain was sequenced using the Illumina MiSeq technique. Resistome analysis was done by annotation of the WGS against the ARG-ANNOT database. The isolate was resistant to all β-lactam antibiotics with the exception of cefepime. The MICs of imipenem and ertapenem as determined by E-test were 12 μg/ml and 2 μg/ml, respectively. Modified Carba NP test showed that the strain was carbapenemase producing. Resistome analysis revealed the presence of a novel metallo-β-lactamase, a chromosomal bla EBR-4 , which exhibited 94.92% and 97.02% nucleotide and protein sequence identities respectively with bla EBR-3 gene of E. falsenii 174,820. Seven and eight amino-acid substitutions were observed with the bla EBR-1 and bla EBR-2 , respectively. We reported the first isolation and genomic description of an extensively drug resistant isolate of Empedobacter falsenii in Nigeria. This report broadens our knowledge of carbapenem resistance in E. falsenii and it will serve as a useful guide in the development of antibiotic use policy., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Carbapenemase-producing Alcaligenes species has been described in only few studies, with none so far from the African continent. Here, we report the whole genome sequence of Peanalcaligenes suwonensis bearing bla VIM-5 metallo-β-lactamase and first detection of carbapenemase producing Alcaligenes faecalis isolated from patients attending tertiary healthcare facilities in Nigeria. The isolates were identified by MALDI-TOF Mass Spectrometry. Antibiotic susceptibility assay, modified Carba NP test and genomic investigation revealed that two isolates of Alcaligenes faecalis and an isolate of Paenalcaligenes suwonensis harboured bla VIM-5 gene. The genome sequence analysis of the P. suwonensis 191B isolate, responsible for acute gastroenteritis, reveal the presence of 18 antibiotic resistance genes coding for resistance to five different classes of antibiotics. Three of the genes (bla OXA-368 , bla CARB-4 and bla VIM-5 ) codes for resistance to β-lactam antibiotics. To our best knowledge, we describe here the first genome sequence of P. suwonensis species and the first detection of class B carbapenemase bla VIM-5 in a clinical isolate of P. suwonensis species and Alcaligenes faecalis in Nigeria. The finding of this study is of concern, as lateral dissemination of the genes into clinically important Gram-negative pathogens is highly likely., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Introduction: measles is a vaccine preventable, highly transmissible viral infection that affects mostly children under five years. We reviewed surveillance data on measles from Nigeria over a five-year period to highlights its burden and make recommendations for improvements., Methods: we conducted a secondary data analysis of measles specific Integrated Disease Surveillance and Response (IDSR) records of all states in Nigeria over a five-year period., Results: a total of 131,732 cases were recorded between January 2012 and September 2016. Most cases 57,892 (43.95%) were recorded in 2013 while the least 11,061 (8.4%) were recorded in 2012. A total of 817 deaths were recorded, with a case fatality rate (CFR) of 0.62%. The highest CFR (1.43%) was recorded in 2012 while the least CFR (0.44%) was recorded in 2016. Only 8,916 (6.7%) cases were confirmed by laboratory tests. The trend of measles cases followed the same pattern throughout the years under review, with cases peaking at March, then gradually reducing to lowest level at June, which was maintained throughout the rest of the year. States in northern region of Nigeria recorded the highest attack rate (Yobe: 480.29 cases per 100,000 population, Sokoto: 284.63 cases per 100,000 population and Katsina: 246.07 cases per 100,000 population) compared to States in the southern region (Rivers: 11.72 cases per 100,000 population and Akwa Ibom: 13.59 cases per 100,000 population). Conversely, States in the southern region recorded the highest CFR (Ebonyi: 13.43% and Rivers: 3.27%)., Conclusion: measles infection remains a burden especially in the northern region of Nigeria. Although measles fatalities declined over the years, laboratory confirmation was sub-optimal. We recommended improvement on routine immunization and strengthening of regional laboratories diagnostic capacities, for successful eradication of measles from Nigeria., Competing Interests: The authors declare no competing interests.