Inelastic Behaviour Of Thin-Walled Circular Steel Tubular Columns Under Pushover And Cyclic Loading

Thin-walled circular steel tubular columns have been used as bridge piers widely around the globe because of their excellent seismic performance: ductility, strength, and energy dissipation capacity. This thesis investigates the inelastic behavior of thin-walled circular steel tubular columns with a uniform section and thin-walled circular steel columns with diaphragms. The loading protocol considered for this study is either pushover or cyclic lateral loading in the presence of a constant axial load. The effects of a pushover and cyclic lateral loading on the behavior of the thin-walled circular steel tubular bridge piers have been evaluated through analysis of failure mode, hysteresis curve, envelope curve, stiffness and strength degradation characteristic, and energy-dissipating capacity, including interaction effects of local buckling and flexural buckling, and post-buckling regimes. The analysis applies the finite element model (FEM) that considers the effect of both material and geometric nonlinearities. Also, in this research a comprehensive parametric study was carried out to investigate the effects of the key design parameters and namely are: the radius to thickness parameter (Rt), the column slenderness ratio parameter (λ), and the magnitude of axial load (P/Py). Finally, a series of proposed formulae for strength and ductility evaluation for thin-walled circular steel tubular columns are given

Awareness and Practice on Biomedical Waste Management among Health Care Personnel in Kenyatta National Hospital

Background: The proper handling and disposal of Bio-medical waste  (BMW) is very imperative. There are well defined set rules for handling BMW worldwide. Unfortunately, laxity and lack of adequate training and awareness in execution of these rules leads to staid health and environment apprehension.Objective: To assess the awareness and practice regarding biomedical waste management among health care personnel in Kenyatta National Hospital (KNH)Design: A cross sectional study design.Setting: Kenyatta National HospitalSubjects: Doctors, Nurses and support staff who have worked in the institution for more than six months and consented were evaluated.Results: The total level of awareness on biomedical waste management among health care personnel was found to be 60%. The doctors scored 51% which was the lowest score the nurses scored 65% which was the highest score while the support staff scored 55%. As for the practices, the results showed that most of the healthcare personnel were aware of the biomedical waste management practices in the hospital with the lowestscores emerging from doctors and this shows no association between knowledge on biomedical waste management and education. When asked how they would describe the control of waste management in the institution 59% said good and 40% said fair while 1% said poor.Conclusion: The present study therefore outlines the gap between  biomedical waste management rules and inadequate state of execution and awareness in practice. It is recommended that enhancement be done to the already existing Hospital Infection Control Committee to supervise all the aspects of biomedical waste management. Periodical training programmes for biomedical waste handling and disposal to the staff with focus on doctors is highlighted

Using detergent to enhance detection sensitivity of African trypanosomes in human CSF and blood by Loop-Mediated Isothermal Amplification (LAMP)

<p><b>Background:</b> The loop-mediated isothermal amplification (LAMP) assay, with its advantages of simplicity, rapidity and cost effectiveness, has evolved as one of the most sensitive and specific methods for the detection of a broad range of pathogenic microorganisms including African trypanosomes. While many LAMP-based assays are sufficiently sensitive to detect DNA well below the amount present in a single parasite, the detection limit of the assay is restricted by the number of parasites present in the volume of sample assayed; i.e. 1 per µL or 103 per mL. We hypothesized that clinical sensitivities that mimic analytical limits based on parasite DNA could be approached or even obtained by simply adding detergent to the samples prior to LAMP assay.</p> <p><b>Methodology/Principal Findings:</b> For proof of principle we used two different LAMP assays capable of detecting 0.1 fg genomic DNA (0.001 parasite). The assay was tested on dilution series of intact bloodstream form Trypanosoma brucei rhodesiense in human cerebrospinal fluid (CSF) or blood with or without the addition of the detergent Triton X-100 and 60 min incubation at ambient temperature. With human CSF and in the absence of detergent, the LAMP detection limit for live intact parasites using 1 µL of CSF as the source of template was at best 103 parasites/mL. Remarkably, detergent enhanced LAMP assay reaches sensitivity about 100 to 1000-fold lower; i.e. 10 to 1 parasite/mL. Similar detergent-mediated increases in LAMP assay analytical sensitivity were also found using DNA extracted from filter paper cards containing blood pretreated with detergent before card spotting or blood samples spotted on detergent pretreated cards.</p> <p><b>Conclusions/Significance:</b> This simple procedure for the enhanced detection of live African trypanosomes in biological fluids by LAMP paves the way for the adaptation of LAMP for the economical and sensitive diagnosis of other protozoan parasites and microorganisms that cause diseases that plague the developing world.</p&gt

Assessment of Socio Demographic Characteristics on Uptake of Tuberculosis Screening by Community Members in Meru County, Kenya

The trend in tuberculosis in Kenya is worrying. TB is the fourth leading cause of death. In 2015 81,518 cases of TB were identified and treated. The Kenya prevalence survey of 2015-2016 found that estimated prevalence is 558/100,000 way above the WHO estimate of 233/100,000. The objective of the study was to determine the effect of socio- demographics characteristics on tuberculosis screening among community members in Tigania East of Meru County. The study design used was cross-sectional survey and targeted 440 household drawn from the five wards randomly and proportionately selected. Key informant interviews and focus group discussions were used to collect qualitative data. Qualitative data was analysed thematically. Quantitative data was analysed using descriptive statistics and inferential statistics using SPSS version 26. The study found out that there were statistically significant association between TB screening and religion (X2 =13.103, df 3; p value=0.004,), monthly income (X2 =14.970, df 6; p value=0.020. The study concluded that religion and monthly income of community members of Tigania East were associated with TB screening. Keywords; Socio demographic, Uptake of TB screening, Community members. DOI: 10.7176/JBAH/10-22-05 Publication date: November 30th 202

Disorders of sexual differentiation as seen at Kenyatta National Hospital

Background: Disorders of sexual differentiation (DSD) are a group of congenital anomalies characterised by discordance between genetic, gonadal and phenotypic sex. There has been remarkable evolution in management over the last decade, including nomenclature, diagnosis and management. There has also been increased awareness and interest from patients and the public, including legal opinion. There has however been no local study to document and evaluate management in Kenya.Objective: To describe management of patients presenting with DSD at Kenyatta National Hospital (KNH) over a 10 year period.Design: Retrospective descriptive study.Setting: Kenyatta National Hospital.Subjects: Patients diagnosed with DSD.Results: A total of 30 patients whose charts were available were reviewed. Age ranged from birth to 19 years (median 5 months) at diagnosis. Presumed gender was assigned at birth in 28 patients. Karyotyping was available in 23(76%) patients. Other common tests included blood tests (23, 76%), ultrasound scan (14, 47%), contrast studies (3, 10%) and exploratory laparoscopy or laparotomy. 46XX and 46XY DSD were the most common conditions encountered (13, 43% and 7, 23% respectively). The commonest operations were correction of hypospadias and orchidopexy (55%), followed by feminising genitoplasty (16%). Only two patients had gender reassignment. Fifteen patients were asked how they feel about their current gender, and 11 expressed satisfaction.Conclusion: DSD is a relatively rare condition. There are also no strict protocols being followed. Management at KNH is acceptable although there is a lack of facilities to carry out many requisite investigations

Rapid and sensitive detection of mycobacterium ulcerans by use of a loop-mediated isothermal amplification test

This work reports the design and evaluation of a rapid loop-mediated isothermal amplification test for detecting Mycobacterium ulcerans DNA based on the multicopy insertion sequence IS2404. The test is robust and specific with a detection limit equivalent to 20 copies of the target sequence (0.01 to 0.1 genome). The test has potential for the diagnosis of Buruli ulcer under field conditions

Counterflow dielectrophoresis for trypanosome enrichment and detection in blood

Human African trypanosomiasis or sleeping sickness is a deadly disease endemic in sub-Saharan Africa, caused by single-celled protozoan parasites. Although it has been targeted for elimination by 2020, this will only be realized if diagnosis can be improved to enable identification and treatment of afflicted patients. Existing techniques of detection are restricted by their limited field-applicability, sensitivity and capacity for automation. Microfluidic-based technologies offer the potential for highly sensitive automated devices that could achieve detection at the lowest levels of parasitemia and consequently help in the elimination programme. In this work we implement an electrokinetic technique for the separation of trypanosomes from both mouse and human blood. This technique utilises differences in polarisability between the blood cells and trypanosomes to achieve separation through opposed bi-directional movement (cell counterflow). We combine this enrichment technique with an automated image analysis detection algorithm, negating the need for a human operator

Site characterization and systems analysis in Central Mekong

The systems addressed in this chapter and in the CGIAR Research Program on Integrated Systems for the Humid Tropics (Humidtropics) broadly include natural systems comprising biophysical, resource and climate realities; social systems made up of people, societies and their institutions; and, what some term as artificial systems built on elements of the first two (Checkland 1981). Agricultural systems, for example, modify natural systems for productive use, add infrastructure to provide markets, and modify human institutions to organize labour and services to enable the agricultural system to function. Regardless of how systems are categorized, they can be simplistically deconstructed into components and the interactions between them. In this chapter we characterize some of the Central Mekong systems, and also address some of the system dynamics, at two basic levels of resolution. Section 2 addresses regional agricultural systems consisting of one or more districts within a country, and includes variations in natural and social systems in addition to agricultural systems. Five regional cases that reflect the diversity across the Central Mekong Action Area are examined and compared. The authors focus on systems at the community or local landscape level, particularly the individual farm household component, and the variation between households within the landscape. Variables include household agricultural practices, household resources, capacity, and links to markets and institutions. Section 3 looks at diversity in the variables among farm households and the implications for livelihoods and well-being. Section 4 examines food security levels arising from specific farm household strategies and performance, how the two are related, and the implications for potential farm interventions. We conclude by comparing the types of systems examined, the differences in types of tools needed, and the differences in questions asked and learning generated. Throughout this chapter, authors refer to data from reports and articles that interested readers can find in Annex I