1,089 research outputs found
Optimum design of reinforced concrete cantilever retaining walls according Eurocode 2 (EC2)
This study investigates optimum design in terms of minimum cost of reinforced concrete cantilever retaining walls. For the optimization process, the evolutionary method which is a combination of genetic algorithm and local search techniques was implemented. Evolutionary method was adopted in this study because it can effectively solve highly nonlinear problems and problems that feature discontinuous functions as demonstrated by several works available in the literature. The popularity of the evolutionary method may also be attributed to its availability as one of the solving methods in Solver add-in tool of Microsoft Excel. This implies that it is freely available and no need to pay for extra license to run any optimization problem. The design variables of the problem are thickness of stem wall, thickness of base slab, width of the heel, width of the toe, area of steel reinforcement for the stem wall and base slab. The objective function was to minimise the total cost of the wall, which includes costs of concrete, steel, forming, and excavation. The constrained functions were set to satisfy provisions and requirements of Eurocode 2 (EC2). Material strength and soil characteristics are treated as design parameters where they are kept constants during solution of the problem. Various material cost ratios were considered. Consequently, optimum design charts were developed for a wide range of wall height, coefficient of friction and surcharge load. Following a comprehensive investigation of the minimum cost problems carried out for different cases, one can conclude that the total cost of the retaining wall is directly proportional to the wall height and surcharge load values, whereas, the cost is almost independent of coefficient of friction
Evaluation of preoperative predictive values of serum CA15-3 and CEA within Sudanese women with breast cancer.
Objectives: Early detection of cancer comprises early diagnosis in symptomatic and screening of asymptomatic individuals. Our aim was to evaluate the significant values of carbohydrate antigen 15-3 (CA15-3) and/or Carcinoembryonic antigen (CEA) in women with breast cancer.Design and setting: This case control study was conducted in Khartoum Teaching Hospital, Khartoum, Sudan.Application of such measurement may be helpful within screening and early detection efforts in such a country like Sudan with poor resources.Methods: We examined by serological radioimmuno-assay methods, significant elevation of CA15-3 and CEA serum samples obtained from 100 women of whom 40% and 35% were patients with histopathologically confirmed breast cancer and benign breast lumps respectively and theremaining 25% were apparently healthy controls. Statistical analysis: Data were analyzed by using a computer SPSS program.Results: Among the 75 patients with breast lumps, 33 (44%) and 31(37.3%) showed high CA15-3 and CEA levels respectively. Of the 40 carcinomas, high expressions of CA15-3 and CEA were found among 28(70%) and 24(60%) respectively. Notably, only 2(8%) of the controls showed lightly elevated CEA.Conclusions: The obtained Specificity of 85.7%, 80% and sensitivity of 70%, 60% for CA15-3 and CEA correspondingly, support the combined application of both markers in screening for breast cancer.Key words: Carcinoembryonic antigen, radioimmuno-assay, breast lump, histopathologicall
A comparison study of histochemical staining of various tissues after Carnoy’s and formalin fixation
Background: The potential problems related to the use of formalin in histopathology, such as health hazards, deterioration of nuclei acids are well-known. The aim of this study was to evaluate the utilization of a Carnoy’s solution fixation in comparison with formalin on subsequent tissue sectioning and histochemical staining.Materials and Methods: Corresponding sections of 25 tissue biopsies of rabbit’s different organs were fixed in Carnoy’s solution and in 10% neutral buffered formalin. Samples were processed using the conventional method and then stained applying five histochemical methods. The degree ofthe quality of the staining was assessed for each method by scoring system (1-10) depending on comparison of the stained tissue sections with illustrated photomicrographs.Results: For the quality of cutting, the best quality was obtained by Formalin (mean = 4.76) then Carnoy’s fixative (mean =3.84). The best quality of Haematoxylin and Eosin staining was obtained by formalin (mean =5.28) then Carnoy's (mean = 4.00). For Alcian blue and Perl’s Prussian blue, the best staining qualities were obtained by Formalin (mean = 4.76 and 5.64 respectively) followed by Carnoy's (mean = 2.88 and 3.92 respectively). For periodic Acid Schiff's the best staining qualitywas obtained following Carnoy's fixation (mean = 4.52) then, the formalin (mean = 3.76).Conclusion: Although, Carnoy’s fluid is a safe fixative and can rapidly penetrate the tissues, but it can’t be a substitute for formalin.Keywords: Haematoxylin, photomicrographs, Eosin staining
Effect of Sources of Organic Manure on Growth and Yields of Okra (Abelmoschus esculentus L.) in Sokoto, Nigeria
Field experiments to investigate the effect of different sources of organic manure (Cow, Sheep and Poultry Manure) on growth and yield of okra was carried out at the Teaching and Research Fadama Farm of Usmanu Danfodiyo University Sokoto, Nigeria during 2007/2008 and 2008/2009 dry seasons. Treatments were laid out in a randomized complete block design (RCBD) with three replications. Data were collected on growth and yield parameters (Plant height, number of leaves per plant, pod length and fresh pod weight). Results obtained indicated that growth and yield of okra was lowest in control treatments which showed that the organic manures used in the study especially poultry manure positively influenced the performance and yield of okra. Poultry manure positively increased okra plant height by 39.4% and number of leaves by 37.8% compared to control treatments. There was no significant effect with respect to number of leaves in 2007/2008. Fresh pod weight was significantly increased by 34.6% with poultry manure compared to control treatments. However, pod length was not significantly affected by the treatments. Based on the findings of the experiments it could be deduced that poultry manure seems to promote higher growth and yield of okra. Thus, it should berecommended for farmers growing okra in this zone.Keywords: Okra, Growth, Yield, Source, Organic Manur
Effect of Fixatives' Temperatures on Subsequent Histochemical Staining
Background: Fixation is complex series of chemical events which differs for the different group of chemical substances found in tissues. Some chemical reactions, including those involved in fixation occur more rabidly at higher temperature.Objectives: Toassess the effect of varying fixatives' temperature on the quality of subsequent histochemical staining.Methods: Rabbit samples were collected including tongue tissue to demonstrate collagen fibers using Van Geison’s stain, and liver tissue to demonstrate cell morphology using Erlich’s haematoxylin. Specimens were divided into pieces; each sample was fixed in the following fixatives: formal saline, neutral buffer formalin (NBF), Carnoy’s and Bouin's fixative in different temperatures as follow 4C°, 25C°, 37C° and 60C°. There after, tissues were embedded in paraffin and cut sections into 5 micron and stained with Ehrlich’s hematoxylin and Van Gieson histochemical stains.Results: For Erlich’s heamtoxylin, formal saline gave the best result for tissues fixed at 60C°; NBF gave the best results at 37C° and 60C°. For Van Geison stain, formal saline and NBF the best results obtained at 37 C°.Conclusion: The study concluded that using 10% NBF, 10% Formal saline, Carnoy’s and Bouin’s fixatives applying different temperatures include 4C°, 25C°, 37C° and 60C° affect the subsequent histochemical staining of Ehrlich’s hematoxylin, and Van Gieson.Keywords: Fixatives, temperature, Van Geison, Erlich’sheamtoxylin, stai
Oral epithelial atypical changes in apparently healthy oral mucosa exposed to smoking, alcohol, peppers and hot meals, using the AgNOR and Papanicolaou staining techniques.
To evaluate cytological atypical changes in apparently healthy oral mucosa exposed to smoking, alcohol, hot meals, and peppers using the AgNOR and Papanicolaou methods. A total of 180 individuals were evaluated, of which 60 were smokers, 34 were alcohol users, 52 were habitual peppers and hot meal (exposed) consumers, 24 were non-exposed, and 10 were patients with Oral Squamous Cell Carcinoma (OSCC), as an internal control. Cytological materials were obtained by brushing of buccal mucosa, on the border of the tongue and on the floor of the mouth, and participants underwent the Papanicolaou test for cytological changes and AgNOR staining for evaluation of the mean number of AgNOR dots per nucleus. SPSS program was used to perform the Pearson chi-square test. The 95% confidence level, Odds Ratio (OR), and the 95% Confidence Intervals (CI) were used.The features of cytological atypia were verified among 10 individuals, including 5 smokers, 2 alcohol users, 2 hot meals and peppers consumers, and one non-exposed. For atypia among tobacco smokers, the adjusted Odds Ratio (OR) and the 95% CI were found to be 2 (0.246-16.24). Increased keratinization was detected among 27 (45%) of the smokers (P < 0.0001), 17 (32.7%) of the pepper and hot meals consumers (P < 0.005), 4 (11.8%) of the alcohol consumers, and among 2 (3.7%) of the non-exposed group. Statistical analyses revealed a greater mean number of AgNORs per nucleus in smokers (3.68) followed by (2.82) alcohol consumers, compared to the habitual peppers and hot meal consumers (2.28) and the non-exposed group (2.00). What's more, 80% of the smears with cytological atypia were identified with 6 +/- 2 AgNOR mean count.The increase of the variables suggests that the evaluation of epithelial atypical changes in individuals exposed to smoking and alcohol carcinogens may be a useful screening tool. While hot meals and peppers didnot seem to be a risk for oral mucosal proliferation, they increased the potency of keratinization and infection. Diagn. Cytopathol. 2010. (c) 2009 Wiley-Liss, Inc
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COVID-19 pandemic related excessive electronic media exposure and mental health in Saudi Arabia
OBJECTIVE: Due to the continued spread of COVID-19 and the emergence of novel mutated viral variants, families all over the world are experiencing wide-ranging stressors that threaten not only their financial well-being but also their physical and mental health. The present study assessed the association between excessive electronic media exposure of pandemic-related news and mental health of the residents of Ha’il Province, Saudi Arabia. The present study also assessed the prevalence of perceived stress, fear of COVID-19, anxiety, depression, and loneliness due to COVID-19-related restrictions in the same population.
MATERIALS AND METHODS: A total of 490 residents of Ha’il Province participated in a cross-sectional online survey during a two-month period (March to April 2021). A validated 38-item self-report survey was used to collect the data.
RESULTS: Significant associations were reported between excessive electronic media exposure and the prevalence of perceived stress (χ2=140.56; p < .001), generalized anxiety (χ2=74.55; p < .001), depression (χ2=71.58; p < .001), COVID-19-related fear (χ2=24.54; p < .001), and loneliness (χ2=11.46; p < .001). It was also found that participants without depressive symptoms were 0.28 times less likely to have been exposed to excessive electronic media exposure (AOR: 0.28; C.I. 0.16-0.48; p < .001). Similarly, participants with no stress/mild stress were 0.32 times less likely to have been exposed to excessive electronic media exposure (AOR: 0.32; C.I. 0.19-0.52; p < .001).
CONCLUSIONS: The findings of the present study suggest an urgent need for educational resilience programs (online and in-person) for susceptible individuals (females, unemployed, urban residents, etc.). Such programs would help them to develop skills to cope with the psychological impact of the COVID-19 pandemic
Oral cancer knowledge, attitudes, and practices among dentists in Khartoum State, Sudan
The dental professions hold an important responsibility in the control of oral cancer and the early diagnosis highly depends on their knowledge. The present study was developed to assess the knowledge, attitude, and practice of dentists in Khartoum State regarding oral cancer prevention and early detection. An administered questionnaire was structured and sent to all licensed 130 dentists working in public dental clinics in Khartoum State. Responses to the questionnaire were analyzed using descriptive and analytical statistics. Although the majority of the dentists were knowledgeable about the major risk factors of oral cancer, more than half of the dentists reported they do not carry out any special examination to detect oral cancer in age 40 and above in asymptomatic patients. Dentists indicated their lack of training as the main barrier for conducting a comprehensive oral cancer examination. Interestingly, the vast majority of the dentists express their interest to have further oral cancer educational and training sessions. The findings of the present study suggested strongly that educational and training interventions are necessary to enhance preventive measures which may lead to reduce mortality and morbidity from oral cancer
Multidimensional Profiles of Health Status: An Application of the Grade of Membership Model to the World Health Survey
BACKGROUND: The World Health Organization (WHO) conducted the World Health Survey (WHS) between 2002 and 2004 in 70 countries to provide cross-population comparable data on health, health-related outcomes and risk factors. The aim of this study was to apply Grade of Membership (GoM) modelling as a means to condense extensive health information from the WHS into a set of easily understandable health profiles and to assign the degree to which an individual belongs to each profile. PRINCIPAL FINDINGS: This paper described the application of the GoM models to summarize population health status using World Health Survey data. Grade of Membership analysis is a flexible, non-parametric, multivariate method, used to calculate health profiles from WHS self-reported health state and health conditions. The WHS dataset was divided into four country economic categories based on the World Bank economic groupings (high, upper-middle, lower-middle and low income economies) for separate GoM analysis. Three main health profiles were produced for each of the four areas: I. Robust; II. Intermediate; III. Frail; moreover population health, wealth and inequalities are defined for countries in each economic area as a means to put the health results into perspective. CONCLUSIONS: These analyses have provided a robust method to better understand health profiles and the components which can help to identify healthy and non-healthy individuals. The obtained profiles have described concrete levels of health and have clearly delineated characteristics of healthy and non-healthy respondents. The GoM results provided both a useable way of summarising complex individual health information and a selection of intermediate determinants which can be targeted for interventions to improve health. As populations' age, and with limited budgets for additional costs for health care and social services, applying the GoM methods may assist with identifying higher risk profiles for decision-making and resource allocations
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