ABSTRACT
It has been realized throughout the years that an ideal combination of high toughness, hardness and strength is required in many engineering applications that need load-bearing capabilities. Ceramics and related materials have significant constraints for structural and particular non-structural applications due to their low toughness and limited strength while having substantially superior hardness than typical metallic materials. For example, hydroxyapatite (HAp) has gained attention for applications in orthopaedic implants, dental materials, drug delivery, etc. Researchers have continued to strive to produce HAp materials with reliable properties within the acceptable Weibull modulus (m) for load bearing. The Weibull analysis (WA) is a statistical analysis adopted widely in reliability applications to detect failure periods. Researchers have confirmed it to be an effective technique to get results on the reliability of materials at a moderately low rate with assured reliability of the material or component. This review summarizes the WA and the steps in the Weibull method for its reliability analysis to predict the failure rate of ceramics like HAp and other related materials. Also, the applications of WA for these materials were reviewed. From the review, it was discovered that Weibull distribution is proven to confer to the feeblest-link concept. For brittle materials, it was revealed that the Weibull Modulus ranges from 2 to 40, and environment, production processes, and comparative factors are well-thought-out contributing factors for reliability. In addition, the confidence interval can be up to 95 %. The frequently used technique for reliability valuation is to syndicate the Weibull statistics. Also, a very narrow distribution is desirable to offer the expected likelihood. Furthermore, when paired with trials, Monte Carlo simulations prove to be a very helpful tool for forecasting the dependability of different estimate techniques and their optimization. Finally, if the equivalent m is anticipated to be high, it signifies that the material has a high degree of homogeneity of properties and high reliability. WA can find application in predicting the dependability and lifetime of materials, making it widely utilized in engineering and other disciplines. It is especially useful for analysing data in which the likelihood of failure per unit of time varies over time.
ABSTRACT
INTRODUCTION: Chronic liver disease is a public health burden worldwide. Portal hypertension is a major portosystemic abnormality in chronic liver disease. This study aimed to determine the main, right, and the left portal vein diameter in patients with chronic liver disease. MATERIALS AND METHODS: A cross-sectional study was carried out at the Abubakar Tafawa Balewa University Teaching Hospital, Bauchi, northeastern Nigeria from December 2018 to September 2019. Ethical clearance was obtained from the institutional review board. A total of 200 subjects were recruited comprising 100 patients with chronic liver disease and 100 age-matched controls, aged 18 years and above. A transabdominal ultrasound scan was carried out measuring the main, right, and left portal vein diameter while lying supine and/or in the right anterior oblique position after overnight fasting, or 6 hours before the scan. Data analysis was done using SPSS version 22.0. Descriptive statistics (mean, standard deviation) and Pearson's correlation were used. RESULTS: There were 106(53%) males and 94(47%) females, aged between 18 and 73 years with a mean age of 46.79 ± 15.43. The main, right, and left portal vein diameter in patients with chronic liver disease was 14.51 ± 0.78 mm, 6.83 ± 0.81 mm, and 6.26 ± 0.74 mm, which were higher than those of their control. The portal vein diameter positively correlated (weak) with age and respiratory phases among participants (P < 0.05). CONCLUSION: This study found the main, right, and left portal vein diameter among patients with chronic liver disease to be larger than those of the controls. Ultrasonography is a reliable diagnostic tool in evaluating portosystemic pathologies.
ABSTRACT
This study was undertaken to determine the type and estimate the prevalence of bacterial organisms on contact surfaces of five close-to-patient facilities in three veterinary health care settings within the Sokoto metropolis of north-western Nigeria. A total of 30 samples (10 from each setting) were collected and analysed using culture, microscopy and biochemical testing. Bacterial species isolated from samples in this study included the following: Bacillus sp. (27.3%), Staphylococcus aureus (15.9%), Listeria sp. (13.6%), Streptococcus sp. (11.4%), Salmonella sp. (6.8%), Escherichia coli (4.5%), Staphylococcus epidermidis (4.5%), Citrobacter sp. (2.3%), Klebsiella sp. (2.3%), Lactobacillus sp. (2.3%), Micrococcus sp. (2.3%), Pasteurella sp. (2.3%), Proteus sp. (2.3%), and Yersinia sp. (2.3%). A higher percentage (64.3%) of the total bacterial isolates were zoonotic in nature and hence of public health significance. Some pathogens have the potential of nosocomial spread. In this study, we seek to establish the first evidence of bacterial presence in the major veterinary health care settings in the Sokoto region of north-western Nigeria. Of particular interest is the hypothesis, which has not previously been formally tested, that nosocomial infections are especially likely to be implicated in both animals and occupational diseases in Nigeria. It was suggested that some of these isolates were associated with the risk of nosocomial and zoonotic infections and hence draws attention to the need to rigorously employ standard veterinary precautions as part of the hospital's infection control programme in an attempt to protect both patients and staff from infections.
ABSTRACT
The prevalence of Campylobacter spp. in cattle in Sokoto State, Nigeria, was determined. The number of samples collected totalled 976, of which 126 (12.9%) yielded Campylobacter spp. The species of Campylobacter isolates from this study were as follows: C. jejuni (65.1%), C. coli (23.0%), C. lari (7.9%), C. hyointestinalis (3.2%) and C. fetus (0.8%). A total of 172 strains of Campylobacter spp. were identified from the positive samples due to identification of more than a single strain (spp.) from a single sample. The strains identified were C. jejuni (62.8%), C. coli (25.0%), C. lari (8.1%), C. hyointestinalis (2.9%) and C. fetus (1.2%). More than one species of Campylobacter was identified in 36.5% of the positive samples. The biotyping in this study revealed C. jejuni biotype I (34.3%) as the most common C. jejuni biotype, while C. jejuni biotype IV (15.7%) was the C. jejuni biotype that was least frequently isolated. However, the most frequently isolated C. coli biotype was biotype I (72.1%) and all the isolates of C. lari were biotype I.
