602 research outputs found
Synthesis of zeolite A using raw kaolin from Ethiopia and its application in removal of Cr(III) from tannery wastewater
BACKGROUND: The commercial production of zeolite A mainly involves costly synthetic chemicals. However, cheaper raw materials such as clay minerals, coal ashes, natural zeolites, solid wastes and industrial sludge have been tested. Based on this, the objective of the present study is synthesis of zeolite A from two sources of raw kaolins (Ansho and Bombowha) from Ethiopia and evaluation of its application in tannery wastewater treatment. RESULTS: The synthesis result indicated high crystallinity (>90%) of zeolite A using Ansho kaolin. Lower grade Bombowha kaolin yielded zeolite A with crystallinity of 80%. In the tannery wastewater treatment study, a real sample having chromium concentration of 2036 mg L-1 was treated, obtaining 99.8% removal and about 200 mg g-1 adsorption capacity of Cr(III) using 100 g L-1 and 5 g L-1 adsorbent dose, respectively. This indicated that the synthesized zeolite A has great potential for Cr(III) removal from tannery wastewater. CONCLUSION: In this study, zeolite A has been synthesized from two sources of kaolin from Ethiopia and has been evaluated in tannery wastewater treatment. The synthesis result indicated the formation of crystals of zeolite A with optimum crystallinity of 91% and the material exhibited chromium removal efficiency of 99.8%
Mycobacterial contamination of environment in pig farms in the Czech Republic between 1996 and 2002
The purpose of this study was to find source of mycobacterial infections in pig farms. A total of 2 411 environmental samples (bedding materials, water, biofilm from pipelines, peat, etc.) were examined by microscopy and culture. Isolates were identified by serotyping and PCR. Mycobacteria were isolated from 579 (24.0%) samples. 47.0% isolates were Mycobacterium avium subsp. hominissuis isolates (IS901-, IS1245+, serotypes 4, 6, 8, 9), 2.2% isolates were M. a. avium (IS901+, IS1245+, serotype 2) and 50.8% belong to atypical mycobacteria comprising of fifteen species. The frequent isolates were found in peat samples (213/65.1%) in which 81.2% isolates comprised M. a. hominissuis. High amount of mycobacteria were isolated from biofilm (36.4%) and water (29.6%). Alike peat, non-pathogenic species were predominant. The third sources of mycobacteria were bedding materials, mostly sawdust (43.6%). Presence of mycobacteria in the animals’ environment leads to economic losses due to meat condemnation in abattoirs
Epidemiology and individual, household and geographical risk factors of podoconiosis in ethiopia: results from the first nationwide mapping
Although podoconiosis is one of the major causes of tropical lymphoedema and is endemic in Ethiopia its epidemiology and risk factors are poorly understood. Individual-level data for 129,959 individuals from 1,315 communities in 659 woreda (districts) were collected for a nationwide integrated survey of lymphatic filariasis and podoconiosis. Blood samples were tested for circulating Wuchereria bancrofti antigen using immunochromatographic card tests. A clinical algorithm was used to reach a diagnosis of podoconiosis by excluding other potential causes of lymphoedema of the lower limb. Bayesian multilevel models were used to identify individual and environmental risk factors. Overall, 8,110 of 129,959 (6.2%, 95% confidence interval [CI] 6.1-6.4%) surveyed individuals were identified with lymphoedema of the lower limb, of whom 5,253 (4.0%, 95% CI 3.9-4.1%) were confirmed to be podoconiosis cases. In multivariable analysis, being female, older, unmarried, washing the feet less frequently than daily, and being semiskilled or unemployed were significantly associated with increased risk of podoconiosis. Attending formal education and living in a house with a covered floor were associated with decreased risk of podoconiosis. Podoconiosis exhibits marked geographical variation across Ethiopia, with variation in risk associated with variation in rainfall, enhanced vegetation index, and altitude
Brief Resilience Among Victims of Ethno-Religious Crisis in Jos: The Role of Gender and Locus of Control
This study was aimed at assessing the role of gender and locus of control as factors that contribute to resilience among victims of ethno-religious crises in Jos, Plateau State of Nigeria. The participants in the study were 189 victims of religious crises in Jos, Plateau state with 104 (55.0%) males and 85 (45.0%) females’ participants. A 2x2 factorial design was used in the study while the Connor-Davidson Resilience Scale (CD-RISC) by Connor & Davidson (2003), was used to assess resilience while locus of control was measured using locus of control scale by Craig, Franklin and Andrews (1984). Three hypotheses were tested using 2-WAY ANOVA. The result showed that there was no significant effect of locus of control on resilience among the participants. F(1,185)=.082, p=.775. The second hypotheses also showed that there was no significant effect of gender on resilience. F(1,185)=.093, p=.761. And finally, the third hypothesis showed that there was no significant interaction effect of locus of control and gender on resilience. F (1,185)=.884, p=.348. The impact of exposure to traumatic events appears to affects both male and female irrespective of their locus of control, as such, further studies should include multivariate factors in order to gain a complete understanding of the concept of resilience. Also, the findings of the study have implications for government, policy makers, management scholar, practitioners as well as victims of ethno-religious crises. Keywords: Gender, Locus of Control, Brief Resilience, Ethno-Religious Crisis DOI: 10.7176/RHSS/11-16-02 Publication date:August 31st 202
Implications of COVID-19 in high burden countries for HIV/TB: A systematic review of evidence
Background: The triple burden of COVID-19, tuberculosis and human immunodeficiency virus is one of the major global health challenges of the twenty-first century. In high burden HIV/TB countries, the spread of COVID-19 among people living with HIV is a well-founded concern. A thorough understanding of HIV/TB and COVID-19 pandemics is important as the three diseases interact. This may clarify HIV/TB/COVID-19 as a newly related field. However, several gaps remain in the knowledge of the burden of COVID-19 on patients with TB and HIV. This study was conducted to review different studies on SARS-CoV, MERS-CoV or COVID-19 associated with HIV/TB co-infection or only TB, to understand the interactions between HIV, TB and COVID-19 and its implications on the burden of the COVID-19 among HIV/TB co-infected or TB patients, screening algorithm and clinical management.
Methods: We conducted an electronic search of potentially eligible studies published in English in the Cochrane Controlled Register of Trials, PubMed, Medrxiv, Google scholar and Clinical Trials Registry databases. We included case studies, case series and observational studies published between January, 2002 and July, 2020 in which SARS-CoV, MERS-CoV and COVID-19 co-infected to HIV/TB or TB in adults. We screened titles, abstracts and full articles for eligibility. Descriptive and meta-analysis were done and results have been presented in graphs and tables.
Results: After removing 95 duplicates, 58 out of 437 articles were assessed for eligibility, of which 14 studies were included for descriptive analysis and seven studies were included in the meta-analysis. Compared to the descriptive analysis, the meta-analysis showed strong evidence that current TB exposure was high-risk COVID-19 group (OR 1.67, 95% CI 1.06–2.65, P = 0.03). The pooled of COVID-19/TB severity rate increased from OR 4.50 (95% CI 1.12–18.10, P = 0.03), the recovery rate was high among COVID-19 compared to COVID-19/TB irrespective of HIV status (OR 2.23, 95% CI 1.83–2.74, P \u3c 0.001) and the mortality was reduced among non-TB group (P \u3c 0.001).
Conclusion: In summary, TB was a risk factor for COVID-19 both in terms of severity and mortality irrespective of HIV status. Structured diagnostic algorithms and clinical management are suggested to improve COVID-19/HIV/TB or COVID-19/TB co-infections outcomes
Localized boundary-domain singular integral equations based on harmonic parametrix for divergence-form elliptic PDEs with variable matrix coefficients
This is the post-print version of the Article. The official publised version can be accessed from the links below. Copyright @ 2013 Springer BaselEmploying the localized integral potentials associated with the Laplace operator, the Dirichlet, Neumann and Robin boundary value problems for general variable-coefficient divergence-form second-order elliptic partial differential equations are reduced to some systems of localized boundary-domain singular integral equations. Equivalence of the integral equations systems to the original boundary value problems is proved. It is established that the corresponding localized boundary-domain integral operators belong to the Boutet de Monvel algebra of pseudo-differential operators. Applying the Vishik-Eskin theory based on the factorization method, the Fredholm properties and invertibility of the operators are proved in appropriate Sobolev spaces.This research was supported by the grant EP/H020497/1: "Mathematical Analysis of Localized Boundary-Domain Integral Equations for Variable-Coefficient Boundary Value Problems" from the EPSRC, UK
Bioimaging using full field and contact EUV and SXR microscopes with nanometer spatial resolution
We present our recent results, related to nanoscale imaging in the extreme ultraviolet (EUV) and soft X-ray (SXR) spectral ranges and demonstrate three novel imaging systems recently developed for the purpose of obtaining high spatial resolution images of nanoscale objects with the EUV and SXR radiations. All the systems are based on laser-plasma EUV and SXR sources, employing a double stream gas puff target. The EUV and SXR full field microscopes-operating at 13.8 nm and 2.88 nm wavelengths, respectively-are currently capable of imaging nanostructures with a sub-50 nm spatial resolution with relatively short (seconds) exposure times. The third system is a SXR contact microscope, operating in the "water-window" spectral range (2.3-4.4 nm wavelength), to produce an imprint of the internal structure of the investigated object in a thin surface layer of SXR light sensitive poly(methyl methacrylate) photoresist. The development of such compact imaging systems is essential to the new research related to biological science, material science, and nanotechnology applications in the near future. Applications of all the microscopes for studies of biological samples including carcinoma cells, diatoms, and neurons are presented. Details about the sources, the microscopes, as well as the imaging results for various objects will be shown and discussed
Influence of Fetal and Maternal Genetic Susceptibility to Obesity on Birthweight in African Ancestry Populations
Fetal and maternal genetic propensity to obesity can influence birthweight. We investigated the effects of fetal and maternal genetic risk of obesity on birthweight and evaluated whether these genetic influences modify the well-known association between maternal pre-pregnancy body mass index (BMI) and birthweight. In 950 mother-baby pairs of African ancestry, a genetic risk score for adulthood obesity was generated for mothers (mGRS) and their babies (bGRS) as the weighted sum of BMI-increasing alleles of 97 single nucleotide polymorphisms known to be associated with BMI. The median GRS value was used as a cut-off to define high or low bGRS and mGRS. High bGRS was significantly associated with 70 g lower birthweight (95% Confidence Interval [CI] = −127.4 to −12.4) compared to low bGRS. mGRS was positively correlated with birthweight but the association was not significant. mGRS modified the significant birthweight-increasing effect of maternal pre-pregnancy BMI (P-for-interaction = 0.03); among mothers with low mGRS, those who were overweight or obese had 127.7 g heavier babies (95% CI = 27.1 to 228.2) compared to those who had normal weight. In summary, fetal obesity genetic risk loci exert direct influence on birthweight, and maternal loci modify the effect of pre-pregnancy BMI on birthweight
Re-envisioning health promotion: Thinking and acting salutogenically towards equity for historically resilient communities
This paper explores how the salutogenic theory can enable us to re-envision health promotion work with marginalized communities, towards an approach that acknowledges and honours their resilience. We use the three core concepts in Antonovsky’s salutogenic model of health – sense of coherence, generalized resistance resources and specific resistance resources – to explore the theory’s relevance to health equity, thus presenting new opportunities for how we might radically re-evaluate current health promotion approaches. We conclude that a more equitable health promotion requires increased participation of marginalized communities in shaping their futures and suggest a new model for historically grounded salutogenic health promotion.publishedVersio
Black Lives Matter in health promotion: moving from unspoken to outspoken
Racism is a public health crisis. Black communities (including Africans, the African diaspora and people of African descent) experience worse health outcomes as demonstrated by almost any measure of health and wellbeing—e.g. life expectancy; disease prevalence; maternal mortality rates. While health promotion has its foundation in promoting equity and social justice, it is clear that however well-intended, we are not affecting meaningful change for Black communities quickly enough. Through this article, we outline the intersection of social determinants of health and anti-Black racism. We describe how in the first 8 months of 2020 Black communities around the globe have been disproportionately affected by COVID-19, while also having to respond to new instances of police brutality. We assert that the time has come for health promotion to stop neutralizing the specific needs of Black communities into unspoken ‘good intentions’. Instead, we offer some concrete ways for the field to become outspoken, intentional and honest in acknowledging what it will take to radically shift how we promote health and wellbeing for Black people.publishedVersio
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