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Purpose Faecal sludge (FS) and organic market waste (MW) have resources that could be recovered by co-composting though not fully explored under changing climatic conditions in Nigeria. This study explored the characteristics and nutrient quality of co-composts produced from pre-treated FS and MW feedstocks in Nigeria. Methods The study was exploratory and analytical in design and co-composting was purposively selected for resource-recovery. The raw faecal sludge (FS) was harvested from septic tanks of households (50%) and institutions (50%) through mechanical evacuation service trucks and dewatered using 0.1% gradient sand filter. The biodegradable MW was sorted and used for further studies. The dewatered FS (DFS) and MW were mixed in ratios 1:3, 1:5 and 1:7, respectively with DFS and MW as controls. Each of the mixes was made into 1m3 heap and co-composted using the windrow method. The experiments were monitored for 88 days with fortnight composite sampling from each mix (13-weeks). The samples were analyzed for temperature, pH, moisture-contents, micronutrients, macronutrients and pollutants using Standard Methods. Results At maturity, N:P:K (%) indicate good composts at 9: 5: 4, 18: 7: 19 and 3: 3: 1 in the 1: 3, 1: 5 and 1: 7 mixes, respectively, while those of controls were: 19:12:12 (DFS) and 17:14:11(MW) with no significant differences between experimental and control mixes. Also, four factors extracted (pollutants, agronomic, macronutrients and micronutrients), explained 78.2% variability. Conclusion The matured co-compost satisfied nutrients and pollutants quality for agricultural use, recovered organic fertiliser from raw domestic and institutional faecal sludge and market waste.

Studies have shown that organic fertilizer, a product of biodegradable organic matter, is not popular among Nigerian farmers because of its low quality. To alleviate this problem, this study was designed to explore the effect of nutrient-rich materials on quality of fertilizer made from market organic wastes. It adopted an experimental study design, comprising organic fertilizer preparation, fortification with natural fortifiers, farm plot experiments and laboratory analyses. The experiment was laid out in a randomized complete block design with factorial arrangement and three replications. The main plots comprised three crops - maize (cereal), soybean (legume) and yam (tuber) while five different fortified organic fertilizers at three rates of applications -2.0, 2.5, and 3.0 ton/ha and control (organic fertilizers without fortification) - formed subplots. Nutrient-rich materials sourced from animal, plant and rock changed the chemical composition of organic fertilizer made from market wastes and yielded better agronomic performances than the synthetic fertilizer. Hence, fortification of organic fertilizer with natural materials which are readily available and environmentally friendly should be promoted among the farmers.

The purpose of this study was to assess the knowledge of prostate cancer and screening and its associated factors in young Black men aged 18 to 40 years. This was a cross-sectional study conducted in a convenience sample of 267 young Black men in Austin, Texas. Knowledge about prostate cancer and screening was operationalized through 14 items, including 12 items from the Knowledge about Prostate Cancer Screening Questionnaire (PC knowledge), and two items assessing dietary knowledge and prostate cancer screening controversy. PC knowledge scores were regressed on age, cues to action, health screening experience, and demographic/personal factors. Most participants were African American men of American origin (65.3%) and were college freshmen (18.9%). PC knowledge scores were low, with mean correct responses of 28.5%, mean knowledge score of 5.25 ± 3.81 (possible score range of 0 to 14, with higher scores indicating higher PC knowledge) and a median score of 5.00. On average, 47% of the respondents replied “Don’t Know” to the questions. Overall, PC knowledge scores were low among these young Black men, especially in domains related to risk factors, screening age guidelines, limitations, and diet. It is thus important that these men be educated more on these important domains of prostate cancer and screening so that the decision to screen or not will be an informed one. Health screening experience, residence area, major field of study, and academic classification were significant predictors of knowledge.

This study was conducted to identify the salient behavioral beliefs of young Black men toward prostate cancer screening, and to identify the issues surrounding their comfortability with prostate examinations. A total of 20 Black men, aged between 18 and 40 years, participated in three focus group sessions between June 2013 and July 2013 in Austin, Texas. Participants were asked open-ended questions about: (a) the advantages and disadvantages of screening to identify salient behavioral beliefs about screening and (b) issues that would make prostate examinations comfortable or uncomfortable to identify comfortability factors. Focus group discussions were tape-recorded, transcribed, and content analyzed to identify emerging themes of salient beliefs and comfortability. Also, nine salient behavioral beliefs toward prostate cancer screening were identified, and eight factors were linked to comfortability with prostate examinations. Given the increase of prostate cancer disparity as a public health issue, understanding the beliefs of Black men of prescreening age (18-40 years) may be crucial to the effectiveness of future interventions to improve screening when recommended at later ages.

The blasting operation is one of the technologies used for breaking rock masses and reducing the rock mass into smaller sizes to improve transportation and further particle separation. The improvement of blast fragmentation supports the maximization of mining operation and productivity. Soft computing and regression model has been developed in this study to optimize small-scale dolomite blast operations in Akoko Edo, Nigeria. WipFrag software was used to analyze the results of 35 blasting rounds. As independent variables, one uncontrollable parameter and five controllable blast parameters were chosen to predict blast particle sizes using four mathematically motivated soft computing model approaches. The prediction accuracy of the developed models was tested using various model performance indices. The study revealed that rock strength influences blast fragmentation results, and based on the rock strength properties, the fragmentation block size increases with an increase in rock strength. The results of the model performance indices used for the evaluation of the proposed models showed that the modified Artificial Neural Network (ANN) called Hunter Point (HP-ANN) has the highest predictive accuracy. A new model evaluator was also developed in this study called the decision factor. Its application indicates that the HP-ANN model is the best model suitable for the prediction of blast fragment size distribution. Therefore, the developed models can be used to predict the blast result mean size (X50) and the 80% percentage passing size (X80) for mining engineering blasting practices. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFAS) are a group of man-made chemicals that are widely present in many industries. Monitoring and analyzing PFAS in Africa is challenging due to the limited availability of mass spectrometry (MS), which is an essential technique for detecting PFAS. This review assesses the scope and impact of the shortage of mass spectrometry instruments in Africa, emphasizing the resulting limitations in monitoring environmental and public health threats. The review analyzes the existing PFAS monitoring, the accessibility of MS instruments, and the technical capabilities within the continent. This study suggests that fewer African countries have sufficient MS instruments, resulting in significant underreport of environmental data and related public health issues. The review proposes financial support and programs to address these difficulties to provide necessary MS instruments. The review suggests that it is highly important to develop regional centers of excellence for PFAS monitoring using MS instruments and investing in training programs to address the gap in monitoring efforts. So, enhancing these are crucial for the successful management of the environment and safeguarding public health from the effects of PFAS contamination.

This comprehensive analysis delves into the landscape of Computable General Equilibrium (CGE) models, examining their historical development, key components, applications, strengths, limitations, and future directions. CGE models have become indispensable tools for understanding the intricate dynamics of modern economic systems, offering a holistic perspective that considers the complex interactions among sectors, households, and governments. The study reveals the strengths of CGE models, including their capacity to provide a comprehensive view of the economy, analyse policy interactions, and incorporate behavioural responses. However, challenges such as data limitations and simplifying assumptions pose inherent limitations. The analysis identifies promising future directions, including the integration of machine learning, leveraging big data, and advancing computational power. By addressing current challenges and embracing these innovations, CGE models can continue to play a pivotal role in economic analysis and policymaking, navigating the complexities of a dynamic and evolving economic landscape.

The recent global pandemic has highlighted an increase in the prevalence of communicable diseases caused by pathogens. The swift transmission of these diseases within a short timeframe presents a substantial risk to public health worldwide. The inefficiency of traditional diagnostic instruments, which need a time-consuming and complex process in the laboratory, is a significant obstacle to medical care. Currently, there is a high need for the advancement of early detection in order to rapidly diagnose infectious diseases and provide on-site results. This is crucial for prompt and early intervention to improve treatment outcomes. This also provides rapid testing and high-quality microbiological detection, comparable to laboratory standards, in a matter of minutes. Prompt diagnosis and subsequent treatment optimization aid in controlling the spread of infectious diseases. Currently, ongoing techniques and methods are used in the advancements of early detection through biosensors. This review examines the integration of early diagnostics with biosensors, specifically in relation to emerging and re-emerging infectious diseases, challenges, and the future perspective.

The progress made in the field of nanotechnology has resulted in the development of nanomedicine agents, which have demonstrated their efficacy as a promising clinical tool in the fight against different types of cancers. Furthermore, Nanomedicine products possess the potential to achieve intricate targeting strategies and multifunctionality. Currently, nanoparticles possess diverse applications across various scientific disciplines and serve as a crucial component in contemporary medical practices. The specimens have undergone analysis for diverse clinical purposes, including serving as drug carriers, delivering tumor genes, and functioning as contrast compounds in imaging. Diverse nanomaterials derived from organic, inorganic, lipid, or glycan compounds, in addition to synthetic polymers, have been employed to advance and enhance novel cancer therapeutics. The present review centers on the utilization of nanoparticles in clinical settings for the purposes of cancer diagnosis and treatment, with a particular emphasis on their function as drug carriers and targeted therapy agents.

The acquisition and analysis of data in digital forensics raise different data privacy challenges. Many existing works on digital forensic readiness discuss what information should be stored and how to collect relevant data to facilitate investigations. However, the cost of this readiness often directly impacts the privacy of innocent third parties and suspects if the collected information is irrelevant. Approaches that have been suggested for privacy-preserving digital forensics focus on the use of policy, non-cryptography-based, and cryptography-based solutions. Cryptographic techniques have been proposed to address issues of data privacy during data analysis. As the utilization of some of these cryptographic techniques continues to increase, it is important to evaluate their applicability and challenges in relation to digital forensics processes. This study provides digital forensics investigators and researchers with a roadmap to understanding the data privacy challenges in digital forensics and examines the various privacy techniques that can be utilized to tackle these challenges. Specifically, we review the cryptographic techniques applied for privacy protection in digital forensics and categorize them within the context of whether they support trusted third parties, multiple investigators, and multi-keyword searches. We highlight some of the drawbacks of utilizing cryptography-based methods in privacy-preserving digital forensics and suggest potential solutions to the identified shortcomings. In addition, we propose a conceptual privacy-preserving digital forensics (PPDF) model that is based on the use of cryptographic techniques and analyze the model within the context of the above-mentioned factors. An evaluation of the model is provided through a consideration of identified factors that may affect an investigation. Lastly, we provide an analysis of how existing principles for preserving privacy in digital forensics are addressed in our PPDF model. Our evaluation shows that the model aligns with many of the existing privacy principles recommended for privacy protection in digital forensics.

Objective: This study was designed to assess the prevalence and associated factors of dental anxiety among adult patients attending a tertiary dental hospital in Nigeria, while also identifying potential predictors of dental anxiety. Method: A total of 177 adult dental patients completed a self -administered questionnaire comprising socio-demographic information and other information relating to medical conditions, pain, health insurance coverage, previous dental visits and self-perception of oral health. Dental anxiety was assessed with the Modified dental anxiety scale. Result: The prevalence of dental anxiety was 10.73% (MDAS=19-25) with overall severity mean score of 13.36±3.41. Age and sex were associated with the level of dental anxiety (p-values of 0.027 and 0.007 respectively). Moreover, age, sex and level of education were associated with mean anxiety levels (p-values of 0.043, 0.009 and 0.015 respectively). Previous dental visits and self-perception of oral health were associated with dental anxiety (p-values of 0.034 and < 0.001 respectively). Sex, marital status, previous dental visits and self-oral health perception were predictors of high dental anxiety (p-values of 0.028, 0.019, 0.033 and 0.001 respectively). Conclusion: Demographic factors, previous dental visits and self-perception of oral health are associated with dental anxiety. Predictors of high dental anxiety are sex, marital status, previous dental visits and self-oral health perception.

Studies have shown that organic fertilizer, a product of biodegradable organic matter, is not popular among Nigerian farmers because of its low quality. To alleviate this problem, this study was designed to explore the effect of nutrientrich materials on quality of fertilizer made from market organic wastes. It adopted an experimental study design, comprising organic fertilizer preparation, fortification with natural fortifiers, farm plot experiments and laboratory analyses. The experiment was laid out in a randomized complete block design with factorial arrangement and three replications. The main plots comprised three crops - maize (cereal), soybean (legume) and yam (tuber) while five different fortified organic fertilizers at three rates of applications -2.0, 2.5, and 3.0 ton/ha and control (organic fertilizers without fortification) - formed subplots. Nutrient-rich materials sourced from animal, plant and rock changed the chemical composition of organic fertilizer made from market wastes and yielded better agronomic performances than the synthetic fertilizer. Hence, fortification of organic fertilizer with natural materials which are readily available and environmentally friendly should be promoted among the farmers. [ABSTRACT FROM AUTHOR]

Cross-domain recommender systems are known to provide solutions to the cold start and data sparsity problems in recommender systems. This can be achieved by leveraging sufficient ratings and users’ profiles in one domain to enhance accurate recommendations in another domain. However, domains with sufficient ratings are not willing to share their users’ ratings with other recommender systems or domains due to users’ privacy and legal concern. Hence this shows a need for a privacy-preserving mechanism that encourages secure knowledge transfer between different domains. This study proposes a privacy-preserving cross-domain recommender system based on matrix factorization. Specifically, the study formally described the privacy requirements of a cross-domain recommender system, which are different from a single domain recommender system. It designs a new framework for a privacy-preserving cross-domain recommender system and then utilized the somewhat homomorphic encryption (SWHE) scheme to ensure users’ privacy. The SWHE scheme was used to encrypt users’ ratings in different domains, shared latent factor approach was implemented between the domains and extracted knowledge was securely transferred from the source domain to the target domain. We prove that users’ privacy is secured throughout the stages involved in the proposed protocol. Experiments on both synthetic and real datasets demonstrate the efficiency of our protocol.

Opportunistic Networks is a new concept that is increasingly gaining ground since it appears as a concrete example of the Internet of Things, Internet of Vehicles, Industrial Internet of Things, and the Internet of Everything with Mobile ad hoc Networks’ characteristics. An Opportunistic Network starts with a Seed OppNet that sets up the network; expands from the Seed OppNet to an extended Seed OppNet through devices’ discovery. The characteristics of Opportunistic Networks make OppNets more challenging than any other networks. So, a deep understanding of OppNets’ characteristics and demands is an unavoidable precondition before proposing any OppNets related scheme. However, under OppNets’ constraints, the relevance of the Opportunistic Networks related articles in literature is yet to be established. Also, most surveys tackling Opportunistic Networks do not give a complete insight into what Opportunistic Networks stand for. This work reviews state of the art on Opportunistic Networks providing three main contributions. First, resorting to the primary definition of Opportunistic Networks, it elucidates what OppNets are, pointing out the particularities of an OppNet, its domains of applications, and challenges. Second, it provides a comprehensive review that encompasses most Opportunistic Networks’ research areas: routing, intrusion detection, authentication, privacy protection, data aggregation, and the technology for OppNets, organising them in a taxonomy. Third, it evaluates the role of the Seed OppNet in Opportunistic Networks related schemes. Any proposed OppNets related scheme, to be relevant to OppNets’ research, should include OppNets’ characteristics and demands.

The increasing urbanization being experienced in African countries exacerbates their current housing needs and tenure insecurity. Despite the strictness of the formal land market in Ibadan, Nigeria, urban residents find it easier to access land from informal land market in the city, which results in incremental housing development. Based on the Self-help Theory, the study examined the contribution of tenure insecurity to the development of incremental housing in peri-urban Ibadan. A cross-sectional research design (relying on quantitative and qualitative data) was employed in the study. A total of 248 heads of household were selected from six Local Government Areas of Ibadan and each one of them was administered a structured questionnaire. Ethical protocols were followed and informed consent was obtained. The study revealed that the majority of these incremental developers was illiterate. Factors that accounted for the incremental development included fear of eviction (which is associated with tenure insecurity), high rent costs and lack of funds (as associated with income poverty). The study recommended enhancing access to secure land titles as this has multiplier-effects on housing.

This study was conducted to identify the salient behavioral beliefs of young Black men toward prostate cancer screening, and to identify the issues surrounding their comfortability with prostate examinations. A total of 20 Black men, aged between 18 and 40 years, participated in three focus group sessions between June 2013 and July 2013 in Austin, Texas. Participants were asked open-ended questions about: (a) the advantages and disadvantages of screening to identify salient behavioral beliefs about screening and (b) issues that would make prostate examinations comfortable or uncomfortable to identify comfortability factors. Focus group discussions were tape-recorded, transcribed, and content analyzed to identify emerging themes of salient beliefs and comfortability. Also, nine salient behavioral beliefs toward prostate cancer screening were identified, and eight factors were linked to comfortability with prostate examinations. Given the increase of prostate cancer disparity as a public health issue, understanding the beliefs of Black men of prescreening age (18-40 years) may be crucial to the effectiveness of future interventions to improve screening when recommended at later ages. [ABSTRACT FROM AUTHOR]

Unripe cardaba banana and plantain slices were processed into flour. The effects of treatment (blanching/unblanched) and drying method (sun, 50ºC and 70ºC) were recorded. The antioxidant properties of the flour samples, sensory evaluation and minerals content were all determined. DPPH, TPC, FRAP and Metal chelating abilities were higher in cardaba flour (89.77 to 99.18%, 15.00 to 46.00 μgGAE/100g, 0.28 to 0.69 AAEμg/g and 38.90 to 96.53%) than in plantain (91.32 to 98.17%, 10.00 to 34.00 μgGAE/100g, 0.28 to 0.52 AAEμg/g and 33.71 to 94.98%) samples. Calcium, zinc and phosphorus were lower in cardaba banana flour compared to plantain flour. In overall acceptability, amala (a traditional South-western Nigerian meal) from blanched and unblanched cardaba banana flour was preferred to amala from blanched and unblanched plantain flour. Amala from oven-dried samples was considered better than sun-dried samples.

The Niger Delta is one of the most prolific hydrocarbon provinces in the world, but information on basinal hydrogeology is scanty. Oilfield brines from nine producer wells in the Miocene reservoirs (2,472.25–3,532.48 m.b.s.l.), offshore Niger Delta, have been investigated along with two seawater samples to understand their hydrogeochemical characteristics in relation to the host rock mineralogy. Chemical analysis revealed that the waters are slightly alkaline and can be generally classified as saline water of the Na–Cl type based on their total dissolved solids (TDS). On the basis of bicarbonate, chloride, and sulphate ions, they are shown to be of connate origin. Relative abundance of major ions is in the following order: Na > Ca > Mg > K and Cl > HCO3 > SO4. Saturation indices (SI) of selected mineral phases calculated using PHREEQC indicate that the dissolution of iron oxide and carbonate minerals may contribute major ions in the formation water. The preponderance of alkali elements suggests the presence of feldspars, which could have resulted from sediments through which the water flows. An inverse relationship is observed between the resistivity of formation water and its TDS, which could be used to calculate resistivity values of formation waters in the area if the TDS contributions are known. Chemical data suggest that the formation waters were derived from seawater, dominantly altered by reverse ion-exchange processes and subsequently by water-rock interactions. Multivariate statistical analyses (correlation and factor analysis) indicate multiple sources of enrichment of ions in the formation waters.

Population sequencing was performed for persons identified with persistent low-level viremia in 2 clinical trials. Persistent low-level viremia (defined as plasma HIV-1 RNA level >50 and <1000 copies/mL in at least 2 determinations over a 24-week period, after at least 24 weeks of antiretroviral therapy) was observed in 65 (5.6%) of 1158 patients at risk. New resistance mutations were detected during persistent low-level viremia in 37% of the 54 evaluable cases. The most common mutations were M184I/V (14 cases), K103N (9), and M230L (3). Detection of new mutations was associated with higher HIV-1 RNA levels during persistent low-level viremia. [ABSTRACT FROM AUTHOR]

Edible plants such as sweet potato are sources of natural antioxidants that can be exploited in the management and treatment of insulin resistance. This present study investigated the effects of the extracts of an orange-fleshed sweet potato on oxidative stress biomarkers (glutathione status and lipid peroxidation) and activities of antioxidant enzymes (catalase, CAT and glutathione peroxidase, GPx) in palmitate-induced insulin resistant C2C12 cells. The intracellular antioxidant status of the cells was also measured using Ferric reducing antioxidant power (FRAP) and Trolox equivalent antioxidant capacity (TEAC) assays. Furthermore, this study determined the effect of the extracts on the regulation of some type 2 diabetes associated genes; glucose transporter 4 (glut4), Nuclear respiratory factor 1 (nrf1), Myocyte enhanced factor 2A (mef2a), Carnitine palmitoyltransferase 1 (cpt1) and Acetyl-CoA carboxylase 2 (acc2). The results showed a significant (p < 0.05) increase in intracellular GSH level, a significant reduction in the level of malonaldehyde and a significant improvement in the intracellular antioxidant status upon treatment of the insulin resistant cells with the extracts. The extracts were also able to positively modulate the expression levels of the type 2 diabetes associated genes. On the other hand, HPLC-MS analysis of the extracts showed the presence of polyphenols which could have contributed to the bioactivity of the extracts through their antioxidant effects.

The increasing demand for natural products as an alternative therapy for chronic diseases has encouraged research into the pharmacological importance of bioactive compounds from plants. Recently, there has been a surge of interest in the therapeutic potential of oleanolic acid (OA) in the prevention and management of chronic diseases. Oleanolic acid is a pentacyclic triterpenoid widely found in plants, including fruits and vegetables with different techniques and chromatography platforms being employed in its extraction and isolation. Several studies have demonstrated the potential therapeutic effects of OA on different diseases and their symptoms. Furthermore, oleanolic acid also serves as a framework for the development of novel semi-synthetic triterpenoids that could prove vital in finding therapeutic modalities for various ailments. There are recent advances in the design and synthesis of chemical derivatives of OA to enhance its solubility, bioavailability and potency. Some of these derivatives have also been therapeutic candidates in a number of clinical trials. This review consolidates and expands on recent reports on the biological effects of oleanolic acid from different plant sources and its synthetic derivatives as well as their mechanisms of action in in vitro and in vivo study models. This review suggests that oleanolic acid and its derivatives are important candidates in the search for alternative therapy in the treatment and management of chronic diseases.

Two patients with splenic epidermoid cysts who presented as acute abdominal emergencies are reported. [ABSTRACT FROM PUBLISHER]

Cardiac arrest is rare in children. Breath-holding, on the other hand, is fairly common. We report a case in which one complicated the other with serious consequences. A review of the literature on the subject was undertaken. [ABSTRACT FROM PUBLISHER]

Objective: We assessed the association of early statin initiation with inpatient mortality among hospitalised COVID-19 patients., Design, Setting and Participants: This observational study emulated a hypothetical target trial using electronic health records data from Northwestern Medicine Health System, Illinois, 2020-2022. We included patients who were ≥40 years, admitted ≥48 hours for COVID-19 from March 2020 to August 2022 and had no evidence of statin use before admission., Interventions: Individuals who initiated any statins within 48 hours of admission were compared with individuals who did not initiate statins during this period., Primary Outcome Measures: Inpatient mortality at hospital days 7, 14, 21 and 28 were determined using hospital records. Risk differences between exposure groups were calculated using augmented inverse propensity weighting (AIPW) with SuperLearner., Results: A total of 8893 individuals (24.5% early statin initiators) were included. Early initiators tended to be older, male and have higher comorbidity burdens. Unadjusted day 28 mortality was higher in early initiators (6.0% vs 3.6%). Adjusted analysis showed slightly higher inpatient mortality risk at days 7 (RD: 0.5%, 95% CI: 0.2 to 0.8) and 21 (RD: 0.6%, 95% CI: 0.04 to 1.1), but not days 14 (RD: 0.4%, 95% CI: -0.03 to 0.9) and 28 (RD: 0.4%, 95% CI: -0.2 to 1.1). Sensitivity analyses using alternative modelling approaches showed no difference between groups., Conclusions: Early statin initiation was not associated with lower mortality contrasting with findings of previous observational studies. Trial emulation helped in identifying and addressing sources of bias incompletely addressed by previous work. Statin use may be indicated for other conditions but not COVID-19., Competing Interests: Competing interests: LP receives funds for unrelated research from Omron Healthcare Co. Other authors have no other conflicts to declare., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Maximizing the use of explosives is crucial for optimizing blasting operations, significantly influencing productivity and cost-effectiveness in mining activities. This work explores the incorporation of machine learning methods to predict powder factor, a crucial measure for assessing the effectiveness of explosive deployment, using important rock characteristics. The goal is to enhance the accuracy of powder factor prediction by employing machine learning methods, namely decision tree models and artificial neural networks. The analysis finds key rock factors that have a substantial impact on the powder factor, hence enabling more accurate planning and execution of blasting operations. The analysis uses data from 180 blast rounds carried out at a dolomite mine in south-south Nigeria. It incorporates measures such as root mean square error (RSME), mean absolute error (MAE), R-squared (R 2 ), and variance accounted for (VAF) to determine the best models for predicting powder factor. The results indicate that the decision tree model (MD4) outperforms alternative approaches, such as artificial neural networks and Gaussian Process Regression (GPR). In addition, the research presents an efficient artificial neural network equation (MD2) for estimating the values of optimum powder factor, demonstrating outstanding blasting fragmentation. In conclusion, this research provides significant information for improving the accuracy of powder factor prediction, which is especially advantageous for small-scale blasting operations., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Author(s).)

Background: HIV seroprevalence in Nigeria is increasing among men who have sex with men (MSM) from 14% to 2007 to 23% in 2014, threatening progress towards ending the epidemic in the country. Expanding access to HIV testing and linkage to care for key populations, like young MSM (YMSM), is critical to end the HIV epidemic in Nigeria. The Intensive Combination Approach to Roll Back the Epidemic in Nigerian Adolescents (iCARE Nigeria) pilot intervention successfully implemented a combination of evidence-based interventions utilizing peer navigators and popular social media apps and platforms to reach young men at risk for HIV exposure, including YMSM. We conducted sequential mixed methods explanatory implementation research to expand on the previously reported effectiveness and implementation outcomes and to explore the determinants and strategies which contributed to primary study results., Methods: We conducted key informant interviews and focus group discussions with 2 peer navigators and 3 study staff at the end of the pilot. We used directed content analysis to understand the quantitative results from the pilot. Using the Implementation Research Logic Model, we were able to identify and map strategies through mechanisms of action from barriers addressed to the reported implementation outcomes including feasibility, acceptability fidelity and adoption., Results: We found that iCARE Nigeria's pilot intervention implementers reported high feasibility, acceptability fidelity and adoption were associated with implementation of strategies which addressed many challenging contextual factors, including social stigma, online social networking, legal barriers surrounding MSM behavior, and the COVID-19 pandemic. These strategies included integration of stakeholders' interests, selection of experienced peer navigators including from the targeted population, training and supportive supervision using an implementation guide, ensuring safety (COVID and legal) and identification of clinics serving the targeted population., Conclusion: Mixed methods using implementation research frameworks provided insights into the strategies and barriers and facilitators they addressed which may explain the success of the pilot. These results can inform strategies needed to scale-up the intervention to youth including YMSM in other areas in Nigeria and the region., Trial Registration Isrctn: ISRCTN94590823, https://doi.org/10.1186/ISRCTN94590823., (© 2023. The Author(s).)