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Abstract This article comprehensively discusses the mechanical and tribological properties of epoxy matrix composites filled with 100μm graphite particulates, at loadings ranging from 0 to 1wt%. The investigation also focuses on the effects of the graphite filler on the wear surface of the specimens, utilizing an optical microscope for analysis. The results revealed a significant decrease in the tensile strength of the composite, with a reduction of more than 50% observed at 1wt% graphite loading. However, the flexural strength exhibited an initial sharp increase at 0.1wt% graphite loading, followed by a decline at higher graphite contents. Moreover, both impact and hardness values demonstrated improvement as the graphite content increased. The addition of graphite particles led to a reduction in the friction coefficient, attributed to the solid lubrication capabilities of graphite. Furthermore, the wear rate exhibited a sharp decrease with an increase in graphite content due to the formation of a lubrication layer at the contact surface, effectively reducing the break-off of the specimen.

Salvianolic acid A (SalA), a bioactive compound extracted from Salvia miltiorrhiza, has garnered considerable interest for its potential in ameliorating the post-stroke neuroinflammation. This review delineates the possible molecular underpinnings of anti-inflammatory and neuroprotective roles of SalA, offering a comprehensive analysis of its therapeutic efficacy in preclinical studies of ischemic stroke. We explore the intricate interplay between post-stroke neuroinflammation and the modulatory effects of SalA on pro-inflammatory cytokines, inflammatory signaling pathways, the peripheral immune cell infiltration through blood-brain barrier disruption, and endothelial cell function. The pharmacokinetic profiles of SalA in the context of stroke, characterized by enhanced cerebral penetration post-ischemia, makes it particularly suitable as a therapeutic agent. Preliminary clinical findings have demonstrated that salvianolic acids (SA) has a positive impact on cerebral perfusion and neurological deficits in stroke patients, warranting further investigation. This review emphasizes SalA as a potential anti-inflammatory agent for the advancement of innovative therapeutic approaches in the treatment of ischemic stroke.

Introduction: Chronic kidney disease is a public health problem of global concern, ranked 11 most common cause of mortality in the world. Its prevalence and risk factors are increasing. However, the disease remained poorly studied in northeastern Nigeria. Objective: This study aims to determine the prevalence and risk factors of chronic kidney disease in Maiduguri, northeastern Nigeria. Methodology: A total of 1,686 adult inhabitants were randomly selected from 10 wards of Maiduguri. Their socio-demographic and relevant clinical data were collected and entered into a well-structured questionnaire. Blood and urine samples were also collected from each participant. Glomerular filtration rates were estimated using the CKD-EPI equation. Participants who had eGFR less than 60ml/minute were considered to have CKD. Results: Out of a total of 1,686 study participants, CKD was found in 366 participants (21.7%), out of whom 218(59.6%) were females(χ = 17.598, p= 0.0001). There were 90 (5.4%) study participants in stage IIIB, 79(4.8%) were in stage IV and 45(2.7%) were in stage V. Using multiple logistic regression analysis; risk factors for CKD among our study participants were: (1) Age (r = 0.971, p = 0.0001), (2) Female sex (r = 0.997, p = 0.0001), (3) BMI >25Kg/m (r = 1.498, p = 0.0005), (4) Hyperuricaemia (r = 0.997, p = 0.0001), and (5) Systolic hypertension (r = 1.608, p = 0.012). Conclusion: Chronic kidney disease is common among residents of Maiduguri, northeastern Nigeria. Further intervention studies are needed to evaluate the impact of controlling the identified risk factors on the prevalence of CKD in Maiduguri.

Lead is one of the most toxic heavy metals ever known by man today, which has zero biological role. It is known to cause anemia and affect the nervous and reproductive systems with irreversible effects. Its continual usage leads to its high accumulation polluting the soil and water bodies with devastating health effects. This research, aimed at isolation and characterization of indigenous lead tolerant bacteria from contaminated soil of Anka. Results of Atomic Absorption Spectrophotometry (AAS) showed high concentration of lead (738 mg/kg) of the affected sites above the EPA standard (400 mg/kg). Similarly, a mineral salt media was used to isolate the bacteria following serial dilution. An indigenous bacterial isolate (Ac) with potential to tolerate up to 3000 mg/L Pb(NO3)2 was isolated and molecularly identified based on 16s rRNA sequencing as Bacillus cereus strain BUK_BCH_BTE2 with the accession number MT160412. The isolate was further characterized for its optimum growth and tolerance conditions using one factor at a time (OFAT). Sucrose with an optimum concentration of 5 g/L was the best carbon source for the isolate. The isolate was found to utilize ammonium sulphate as the best nitrogen source at a concentration of 2.5 g/L, with an optimum pH and tempertaure of 7.0 and 37 °C respectively. A concentration of 1000 mg/L Pb(NO3)2 was found to be the optimum concentration for the isolate. The optimum incubation time and inoculum size were found to be 48 hrs and 100 μL respectively. The fact that the isolate could tolerate high Pb(NO3)2 concentration makes it suitable for future bioremediation work involving lead.

Diarrhea caused by multidrug-resistant Escherichia coli (E. coli) is an important and common problem in companion animals, especially dogs. Moreover, these dogs may serve as a reservoir of pathogenic strains of E. coli that may cause enteric and extra-intestinal infections in humans and other animals. This study was conducted to investigate the antibiotic susceptibility pattern of E. coli isolates from diarrheic dogs in Maiduguri Metropolis, Borno State, Nigeria. In fecal samples of 200 dogs with diarrhea, 147 E. coli strains (73.5%) were isolated and characterized by the standard bacteriological techniques (culture, biochemical tests, and antimicrobial susceptibility testing). Out of the 147 positive isolates, 45, 50, and 52 were from Elkanemi Park, Magaram, and Sabon gari wards respectively. The isolates show 100% resistance to chloramphenicol, cefuroxime, and ceftriaxone, 96.6% to amoxicillin, and 95.9% to gentamicin, while all (100%) were susceptible to ciprofloxacin. All the isolates showed multiple antimicrobial resistance. The result of the current study showed that dogs in Maiduguri are important reservoirs of multidrug-resistant E. coli. Therefore, it is important to adopt and apply guidelines for the correct use of antimicrobials in small animal practice to reduce the emergence of multidrug resistance among E. coli in companion animals.

This research was performed on uropathogenic Escherichia coli (E. coli) isolates and established the genes of resistance to ciprofloxacin between the isolates. A total of one hundred and three urine samples were tested for uropathogenic E. coli which were obtained from dogs with urinary tract infections (UTIs) using cultural isolation, antimicrobial susceptibility test, and polymerase chain reaction (PCR). The results revealed that genes associated with ciprofloxacin resistance are 24.3% positive for E. coli. The E. coli isolates were resistant to both ciprofloxacin and ampicillin (100%), highly susceptible to chloramphenicol (84.0%), and less susceptible to gentamycin (44.0%) and amikacin (40.0%). The PCR tests showed the presence of the ParC (in 25 samples; 100%), GyrA (in 25 samples; 100%), and GyrB (in 4 samples; 16.0%) genes. The findings of the present study showed an upsetting rate of ciprofloxacin and ampicillin resistance among the E. coli isolates from dogs with UTIs.

BACKGROUND: Escherichia coli (E.coli) is one of the most common and important causative bacterium of urinary tract infections (UTIs) in both dogs and humans. OBJECTIVES: This study aimed to identify virulence genes and a phylogenetic group of E. coli isolated from the urine of dogs suffering from UTIs. METHODS: E. coli were isolated from urine of dogs suffering from UTIs and tested for the presence of the virulence genes using conventional polymerase chain reaction (PCR) and sequencing method. On day 60 after immunization, half of the fish in each treatment was challenged intraperitoneally and the re- maining half of fish in the oral receiving bacterin groups were challenged by bath method with 1 LD50 and 1 LC50 of a Y. ruckeri local virulent isolate respectively. RESULTS: Out of a total of 103 samples, 25 were found to be positive for E. coli, of these 20 (80.0%) were identified as aer, 14(56.0%) as pap , 12(48.0%) as sfa, 8(32.0%) as afa, 5(20.0%) as hly and 5(20.0%) as cnf1 genes. None of the isolates carried cnf2 genes. CONCLUSIONS: The study demonstrated a high occurrence of virulence genes. The phylogenetic compar- isons of these gene sequences detected in uropathogenic E. coli isolated from dogs showed high similarity to those present in the urine of humans with urinary tract infection. Phylogenetic comparisons of the virulence genes revealed that hly, sfa , cnf1 and pap matched to group B2, afa to group A and aer to group B2 and D.

There is growing concern among regulators and investors over the depreciation in the value of listed insurance firms in Nigeria. The study examines the value relevance of the information content of IFRS 4: Insurance Contracts disclosure of listed insurance firms in Nigeria for the period 2012 to 2020. It further compares value relevance of accounting numbers, with high IFRS 4 disclosures and those with lower disclosures. The study adopted correlational research design. The population for the study consisted of all the 26 insurance firms listed on the Nigerian Stock Exchange as at 31st December 2020, with a sample size of 15 firms. The Ohlson Price Model was adopted for the study. Using robust ordinary least square regression, the study found IFRS 4 disclosures to be value relevant. Also, EPS of Insurance firms with high compliance with IFRS 4 is not more value relevant than that of firms with low compliance with IFRS 4, BVPS of Insurance firms with high compliance with IFRS 4 is more value relevant than that of firms with low compliance with IFRS 4. Overall, findings from the study strengthen the position that IFRS improves the quality of accounting information in annual reports. Furthermore, the study recommends among others that management of insurance firms should work towards improved compliance with IFRS 4 as this would boost investor confidence thereby improving their performance in the stock market.

There has been a concern over absence of empirical works on value relevance of adoption of international accounting standard on agriculture. This paper examines the incremental value relevance of IAS 41 adoption on the value relevance of accounting information of listed agricultural firms in Nigeria. The study covered the period of sixteen years with eight years pre and eight years post adoption. The study also covered all the five listed agricultural firms in Nigeria. Using efficient market hypothesis as theory and OLS regression model as data analysis technique, the study found that the accounting numbers (BVPS, EPS and CASH) jointly explain the variation in SHP of listed agricultural companies in Nigeria for the period 2004 to 2019. However, the incremental coefficient of IAS 41 book value per share (BVP*DV) is statistically significant but it is negative which signifies there is decremental value relevance. Similarly, earnings per share (EPS*DV) is statistically significant and is positive which means that the adoption of IAS 41 had led to incremental value relevance. However, cash flow per share is not statistically significant signifying that it has no any incremental value relevance as a result of changes caused by the adoption of IFRS. The study recommends that there is the need for through examination of other proxies of accounting numbers, such as management of income and recognition of loss to understand more the impact of IAS 41 adoption.

The study investigated the impact of some firm specific attributes on compliance with International Accounting Standard (IAS) 41 of all 5 listed agricultural firms in Nigeria from 2012 to 2019. The study used secondary source of data collected from annual reports published by the firms and the data was analyzed using multiple regression. Findings from the study showed that biological assets intensity and firm size are positively and significantly related to compliance with IAS 41 disclosures, while leverage is negatively and significantly related to compliance with IAS 41 disclosures. Based on the findings the study recommends that listed agricultural firms should increase their biological assets as this leads to increase in compliance with international accounting standard issued by IASB to enhance the value of the firms. The firms should also make their capital structure less geared with focus more on equity than debts as more leverage leads to decrease in compliance with the standard. Furthermore, as much as possible, firms should enlarge the size of their firms as this leads to higher level of compliance with IAS 41 disclosures.

The study examines how proactive monitoring by regulatory authorities and external auditors affect compliance with International Financial Reporting Standard (IFRS) in Nigeria. Data is hand collected from 154 companies that mandatorily adopted IFRS in the year 2012. The study uses the unweighted index in determining the extent of compliance with the disclosure requirements of 10 standards and uses multiple regressions in examining how proactive monitoring affects compliance with IFRS. The results show that the overall level of compliance is 61% and the regulatory bodies under insurance companies and firms audited by Big-4 auditors significantly and positively affect the level of compliance with IFRS disclosures. The study recommends an increase in vigilant in monitoring compliance with IFRS by the regulatory bodies supervising non-financial firms and by local audit firms to improve compliance.

Aim: To determine the presence of MRSA in hunting dogs in Maiduguri metropolitan. Materials and Methods: Phenotypic methods used includes microscopic technique, colony morphology study, catalase-coagulase tests, and the use of mannitol salt agar test, oxacillin resistance screening agar base, and antibiotic susceptibility testing methods. Genotypic approach was used for deoxyribonucleic acid extraction, and the presence of nuc and mecA gene was detected using polymerase chain reaction (PCR) techniques. Results: Examination of 416 swab samples from nasal and perineal region of dogs revealed a total of 79.5% of S. aureus, where 62.5% of the isolates were MRSA. Molecular analysis revealed that 7nuc genes specific for S. aureus from 20 presumptive MRSA assay were all mecA PCR negative. The isolates were sensitive to gentamicin and ciprofloxacin but proved resistant to cefoxitin and oxacillin. Conclusion: High isolation rate of MRSA was found in hunting dogs. Significant level (p

This is a conceptual analysis of the relationships between external debt and capital formation geared towards a proper assessment and understanding the experiences of Sub Saharan African countries external debts experiences. The study established that debt in general and external debt in particular is a necessary evil that all economies survive with. During the five decades of external debt experiences in SSA, all indices have indicated adverse relationships amongst and between all variables of interest in these countries. Most important of the negative consequences was the debt overhang and crowding out effects and their attendant effects on the economies. The study has shown that it has negatively affected the positive development of capital formation being one of the essential macroeconomic variables for a sustained economic development.

The goal of this study is to treat pineapple leaves fiber (PALF) with chitosan for antimicrobial properties. The treated PALF with chitosan was then crosslinked with crosslinking agent; butanetetracarboxylic acid (BTCA) to preserve chitosan in the PALF structure. The effectiveness of chitosan and crosslinking agent towards PALF was determined using untreated PALF, PALF treated chitosan, PALF treated chitosan (wash), PALF treated chitosan/BTCA and PALF treated chitosan/BTCA (wash). After the treatment with chitosan and BTCA, the treated PALF undergone the washing process to determine the effectiveness of BTCA to avoid the removal of chitosan from PALF during washing. The presence of chitosan in the PALF was confirmed using Fourier Transform Infra-red (FTIR) analysis. The treated PALF was then characterised in terms of its antimicrobial activity and mechanical properties. Antimicrobial activity test confirmed the presence of chitosan successfully retarded the growth of microbe. Tensile test analysis revealed the untreated PALF has the highest tensile strength compared to all treated PALF. In contrast, young modulus of the treated PALF shows increment relative to the untreated PALF. This study is particularly important for the further application of PALF or other natural fibers especially in medical and textile industry.

The degradation of products is an integral part of their life-cycle, often following predictable trajectories. However, sudden, unexpected events, termed 'shocks', can substantially alter these degradation paths. Shocks can significantly influence the pace of degradation, leading to accelerated system failure. Moreover, they may initiate changes in degradation patterns, transitioning from linear to non-linear or random trajectories. To address this challenge, we present a novel multi-state reliability model for competing failure processes that account for degradation-shock dependencies by considering the state-varying degradation pattern. The degradation process is divided into s-states, with each state treated according to its pattern based on the time-transform Wiener process. The reliability function is derived based on soft failure caused by continuous degradation involving the s-states, the sudden increase in degradation caused by random shocks, and hard failure due to some shock processes. Additionally, we performed a sensitivity analysis to determine which parameters have the most significant impact on product reliability. Due to the complexity of the likelihood function, we adopted the ABC method to estimate the model parameters. A simulation study and a practical application with micro-electro-mechanical systems (MEMS) degradation results are used to demonstrate the efficiency and effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

Context: Interindividual variability in pain is modified by interactions of multiple biopsychosocial factors. Though there are reported findings on pain variability from studies around the world, the relationship between pain outcomes and anthropometric profiles remains unclear due to conflicting findings. Aim: This study was designed to investigate relationships between experimental pain outcomes and anthropometric profiles in a healthy Nigerian population. Materials and Methods: One hundred and sixty-one healthy volunteers aged 20 to 65 years were recruited for the study. Experimental pain was induced using cold pressor pain, pressure pain, and ischemic pain procedures. Results: We found that subjects with a normal body mass index (BMI) had a statistically significant higher ischemic pain tolerance than their obese counterparts. Right-handed participants had higher cold pressor pain thresholds than their left-handed counterparts, and the difference was statistically significant. Hb genotype and blood groups affected experimental pain outcomes. There was a statistically significant negative correlation between BMI and ischemic pain tolerance. Conclusion: We concluded that the association between BMI and experimental pain outcomes depends on the type of pain induction method used. Right-handedness appeared to be associated with increased cold pressor pain threshold. [ABSTRACT FROM AUTHOR]

This article proposes a flexible additive model that adequately describes complex reliability and survival data. The proposed methodology, referred to as the flexible exponential power-Gompertz (FEPG4) distribution, is able to characterize the behavior of a complex system whose failure times have bathtub-shaped, with clear burn-in and wear-out change points and a low, yet lengthy, flat middle segment as its underlying failure rate distribution. We discuss some properties of the model. Parameter inferences are proposed under maximum likelihood and Bayesian techniques. We determine the Bayes estimators of the FEPG4 parameters and used Hamiltonian Monte Carlo for posterior simulations. Extensive simulation experiments are performed to validate the proposed estimators. For assessing the potential of the FEPG4, the model is compared with other recent bathtub distributions constructed via the same approach on devices' failure and running times (censored and non-censored case) and failure times of some devices, each with the bathtub failure rate. Seven parametric and non-parametric selection criteria and other supporting plots are utilized for comparison purposes. Findings indicate that the FEPG4 model might be the best alternative for representing device failure times, particularly when the bathtub-shaped failure rate of the available data clearly illustrates its three phases. [ABSTRACT FROM AUTHOR]

Purpose - The argument whether gold is a hedge or haven is a debatable issue. Mainly, hedge is a class of asset that is negatively correlated with another asset or portfolio on average. On the other hand, a safe haven is an asset or portfolio which is negatively correlated with another asset or portfolio at the time of market turmoil. Therefore, the purpose of this research is to take Saudi Arabia as an example to examine the relationship of gold price in Saudi Arabia with key determinants such as the stock market index, oil prices, exchange rate, interest rate and consumer price index (CPI) by application of the autoregressive distributed lag model (ARDL). Design/methodology/approach - The ARDL analysis was employed by using six variables based on the application of monthly time series data that were collected from 2011 to 2015. Findings - From the present analysis, it has been discovered that gold is useful as a portfolio hedge and as a hedge against inflation because it is not affected by the CPI. External factors, for example, financial crisis, may be harmful to the CPI, thus adding a certain percentage of gold in the investment portfolio may assist in decreasing the level of risk at the time of financial turmoil. Originality/value - Because gold seems to be a useful portfolio hedge, as well as an inflation hedge, government policies to curb the import of gold may be futile. The present research suggests that policies that directly address the causes of inflation and provide alternative investment opportunities for retail investors may better serve the objective of decreasing gold imports.