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An ergonomic risks assessment for manual and motor-manual pruning by Sibiya, Zimbili Bonisiwe
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Page will reload when a filter is selected or excluded.- "Background: Annotation and Image Markup on ClearCanvas Enriched Stroke– phenotyping Software (ACCESS) is a novel stand-alone computer software application that allows the creation of simple standardized annotations for reporting brain images of all stroke types. We developed the ACCESS application and determined its inter-rater and intra-rater reliability in the Stroke Investigative Research and Educational Network (SIREN) study to assess its suitability for multicenter studies. Methods: One hundred randomly selected stroke imaging reports from 5 SIREN sites were re-evaluated by 4 trained independent raters to determine the inter-rater reliability of the ACCESS (version 12.0) software for stroke phenotyping. To determine intra-rater reliability, 6 raters reviewed the same cases previously reported by them after a month of interval. Ischemic stroke was classified using the Oxfordshire Community Stroke Project (OCSP), Trial of Org 10172 in Acute Stroke Treatment (TOAST), and Atherosclerosis, Small-vessel disease, Cardiac source, Other cause (ASCO) protocols, while hemorrhagic stroke was classified using the Structural lesion, Medication, Amyloid angiopathy, Systemic disease, Hypertensive angiopathy and Undetermined (SMASH-U) protocol in ACCESS. Agreement among raters was measured with Cohen’s kappa statistics. Results: For primary stroke type, inter-rater agreement was .98 (95% confidence interval [CI], .94-1.00), while intra-rater agreement was 1.00 (95% CI, 1.00). For OCSP subtypes, inter-rater agreement was .97 (95% CI, .92-1.00) for the partial anterior circulation infarcts, .92 (95% CI, .76-1.00) for the total anterior circulation infarcts, and excellent for both lacunar infarcts and posterior circulation infarcts. Intra-rater agreement was .97 (.90-1.00), while inter-rater agreement was .93 (95% CI, .84-1.00) for TOAST subtypes. Inter-rater agreement ranged between .78 (cardioembolic) and .91 (large artery atherosclerotic) for ASCO subtypes and was .80 (95% CI, .56-1.00) for SMASH-U subtypes. Conclusion: The ACCESS application facilitates a con cordant and reproducible classification of stroke subtypes by multiple investigators, making it suitable for clinical use and multicenter research. 1 results 1
- Africa 1 results 1
- Background: In women health, ultasound is well established as a safe tool, and it is often the first imaging modality employed in the, screening, investigation and treatment of conditions in obstetrics and gynaecology. However, women's misconceptions about health issues, aetiology and treatment of diseases conditions may have negetive impact on thier health care seeking behaviour. Client's perspective of diagnosis including investigation process is therefore crucial in health care. This study aimed at finding out the misconceptions expressed by clients about ultrasound, and the potential predictors associated with this attitude among women in Nigeria. Method: A descriptive cross-sectional survey was conducted among 3137 women who presented for transabdominal ultrasound scan between August and November 2010 in two referral hospitals in Nigeria. Data were obtained using a questionnaire. Descriptive and multivariate analysis was performed applying logistic regression analysis; predictors of misconceptions expressed by clients about ultrasoung, and misconception among women in Nigeria were identified using SPSS statistics (SPSS Inc, Chicago, IL) version 17 software. Results: The mean age of the women was 33.8 years (standard deviation=7.0), with 88.8% currently married. More than half of the respondents had tertiary education (56.6%), followed by secondary school education (34.5%), primary education(7.8%) and no formal education (1.1%). There were 59 women who held the misconception that ultrasound was dangerous to health accounting for 1.9% of the study population. The reasons given by this group of women included; 'ultrasound can kill or destroys the body cells'(35.6%); 'it can cause cancer' (15.3%); 'the radiation is only dangerous to some organs of the body' (6.8%); 'it can harm or deform the fetus'(6.7%); 'it is only dangerous when exposure is frequent'(5.1%) and 'only dangerous when handled by unskilled medical personnel' (1.7%). Conclusion: This study provides insight to the wide range of issues about clients' perception and misconception regarding ultrasound safety. These issues have to be addressed to improve better compliance and patronage about ultrasound scans in Nigeria. We suggest that robust conseling sessions is imperative to address all the views and possible concerns of clients to improve better service delivery. 1 results 1
- Background: Radiological imaging is mandatory, when investigating patients with low back pain (LBP). A minimum of three plain radiographic views of lumbosacral spine are routinely requested for by the attending clinicians. Objective: The study therefore carried out to determine if only one view will be sufficient in the initial screening of patients with low back pain. Material and Methods: The antero-posterior (AP) and lateral plain radiographs of patients referred to the radiology department on account of low back pains in an eighteen month period (June 2007 to Novermber 2008) were reported by two certified radiologists. The findings were subjected to statistical analysis. The kappa agreement for two independent reports was between 0.602 and 0.908. Results: The radiographs for 638 patients were reviewed. 365 (57.2%) were females and 273(42.8%) were males. The age ranged from 20 years to 85 years with a mean of 56.4 years. Within the age group of 20-69 years, females were found to significanlty present earlier than with LBP (P<0.041). The AP view had a significantly higher rate of reported normal findings that the lateral view (p<0.000). Osteophytic outgrowth was the commonest finding in both views although the rate of detection was higher on the lateral view, as with the other abnormal findings. Conclusion: This study shows that the lateral radiographs show significantly more findings than AP on plain radiographs. It is therefore recommended that lateral radiograph is adequate in the initial screening of patients with low back pain. 1 results 1
- Cancer 1 results 1
- DICOM application 1 results 1
- Dose optimization 1 results 1
- Empirical Formula, 1 results 1
- Graphical, 1 results 1
- Image Processing, 1 results 1
- Lagoon. 1 results 1
- Leaf Area 'Index, 1 results 1
- Leaf Area Index (LAI) is a concept that cuts across agricultural sciences and agricultural engineering with an encapsulating feature in environmental engineering. It is one of the most difficult to quantify properly owing to large spatial and temporal variability. This paper discusses briefly LAI and the use of three methods which are non-destructive in determination of its value for cowpea, namely: the empirical formulae, the graphical and the image processing methods. Cowpea seeds were planted and samples were marked for determination of LAI by the three methods. The results showed that image processing as a more accurate and promising method compared to the other two 1 results 1
- Local reference dose levels 1 results 1
- One of the objectives of x-ray examination is high quality images; however administered radiation doses may be harmful to patients‟ health. Data on radiation dose to patients are scarce, and thus hinder the determination of local and national reference dose levels specific to a country owing to the differences in patient anatomy and radiological practice among nationals of different countries. This study was therefore, designed to determine the patient doses, local reference dose levels and estimate cancer risk based on administered dose at selected radiodiagnostic centres in Southwestern Nigeria. Twelve radiodiagnostic centres were purposely selected across Lagos (3); Ogun (2); Oyo (1); Osun (4) and Ekiti (2) for this study. Exposure parameters including: peak voltage; tube load (mAs); focus-to-skin distance were obtained from x-ray machines during radiographic procedures. Quality control (QC) tests were performed using standard calibration method. Anthropometric data from 689 consented subjects were obtained for chest (353) Postero-Anterior (PA) and Antero-Posterior (AP) for abdomen (20), pelvis (35), skull (56), lumbar spine (87), thigh (12), leg (46), knee (17) and hand (63) examinations. Measurement of Entrance Surface Dose (ESD) was carried out with thermoluminescent dosimeters and converted to Dose-Area Product (DAP). Organ Dose (OD) and Effective Dose (ED) were determined using appropriate software. Organ doses were used to estimate the expected number of cancer incidences resulting from the examinations. Preliminary Local Reference Dose Levels (PLRDLs) were determined, and Patient Parametric-Exposure Estimation (PPEE) models which served as guides in the choice of appropriate exposure parameters for dose optimisation were developed. Data were analysed using descriptive statistics and compared with National Radiological Protection Board levels. The QC results showed that 66.7% of the x-ray machines fall within the internationally acceptable tolerance limit of ±5.0% of exposure parameters reproducibility. The ESD (mGy) for chest PA, abdomen AP, pelvis AP, lumbar spine AP, skull AP, leg AP, knee AP, hand AP and thigh AP were 2.32 ± 0.19, 11.72 ± 2.62, 4.05 ± 0.54, 4.74 ± 0.72, 7.07 ± 0.67, 1.27 ± 0.19, 1.59 ± 0.34 ± 0.19,0.50 ± 0.05; and the DAP (Gy cm2) were 3.06 ± 0.30,17.16 ± 4.96, 3.28 ± 0.47, 2.72 ± 0.44,4.53 ± 0.05,1.15,1.53 ± 0.23,0.92 ± 0.13,0.18 ± 0.02 for chest PA, abdomen AP, pelvis AP, lumbar AP, skull AP, leg AP, knee AP, hand AP and hand AP projections respectively The ED ranged from. The ranges of cancer incidences expected per annum for patients undergoing chest PA examinations for different organs were: lung (227-452), breast (28-207), easophagus (8-26), stomach (28-78) and liver (14-95). The proposed PLDRLs for ESD (mGy) and the corresponding DAP (Gy cm2) were;2.95(3.14), 22.31(28.59), 6.63(4.77), 5.87(3.20), 9.04(5.06), 1.51(2.04), 2.78(2.09), 2.39(1.44), 0.69(0.25) chest PA, abdomen, pelvis, lumbar spine, skull, leg, knee, hand and thigh (AP projections) respectively. The determined PLDRLs were higher than the National Radiological Protection Board reference levels by factors ranging from 1.70-19.70 and 2.20-31.40 for ESD and DAP, respectively. The developed models for estimating patient thickness from weight () were: for standard male and female adults respectively. Patients undergoing selected diagnostic x-ray procedures in Southwestern Nigeria received high doses and have increased risk of cancer. The established local reference levels could help in dose optimisation for radiological practices in Southwestern Nigeria. 1 results 1
- Spatio–temporal variation in Chlorophyll, Nutrients and Primary Productivity of some selected sampling stations in Lagos lagoon were investigated using conventional method from November 2019 to July 2020, in order to compare the result with data from satellite image using MODIS Aqua. Global Positioning Receiver was used to capture the geographic coordinates of the sampling stations. Water sampling was carried out monthly using standard methods during wet and dry seasons. The observed data were subjected to statistical analysis using Microsoft Excel and SPSS. version 20. In wet season, the highest mean value for Chlorophyll a (1.15±0.02 μg/L) was recorded in Ofin while the lowest values (0.06±0.01 μg/L) was observed in Okobaba. During the dry season, the highest mean value (0.75±0.10 μg/L) was in Ofin while the lowest mean value (0.27±0.0.08 μg/L) was recorded in Ibeshe. The MODIS satellite variation in chlorophyll-a showed that the highest value of highest recorded value (1.37±0.00 μg/L) was in wet season (Ijede) while the lowest value (0.12±0.01 μg/L) was observed in dry season (Okobaba). The highest transparency value (0.97±0.01 mg/L) was recorded in dry season (Ofin) while the lowest value (0.35±0.25 mg/L) was recorded in wet season (Oworonsoki). The highest mean value of Surface Sea temperature was recorded in the dry season of Apapa (30.28±1.15oC) while the lowest mean value (26.41±1.15oC) was observed in Okobaba in the wet season. The chlorophyll-a concentration analyzed using standard method and MODIS satellite, in both dry and wet seasons in the sampled stations differ greatly from one another in terms of the mean concentration. The primary productivity of Lagos Lagoon was relatively low, with no significant spatial variations between sampling stations. The results of sea surface temperature, transparency and chlorophyll ‘a’ estimation from the MODIS revealed that the values were positively correlated with laboratory result with r2-value of 0.67, 0.80 and 0.77. This indicates that MODIS data and laboratory results generated for Lagos Lagoon were positively related. 1 results 1
- Statistical Analysis 1 results 1
- Stroke 1 results 1
- The Impact of solid waste disposal at the Ring Road district of Ibadan metropolis, southwestern Nigeria, on the adjoining surface and ground-water sources, has been Investigated. The basement rocks include Precambrian quartzites and quartz-schists that have been extensively weathered. In this study, the geophysical survey Involved 5 electrical imaging lines, while the hydrochemical database comprised 4 samples of surface water and 6 samples of groundwater from dug wells. The samples were analysed for turbidity, pH, conductivity, total hardness, total dissolved solids (TDS), alkalinity, Cl, No3, SO42, PO43, Na, K+, Mg2 and Fe2. The results show that water bodies located in a down gradient direction and in close vicinity of the landfill, has received significant inputs of inorganic pollutants. Statistical analyses indicate positive correlation (p<0.05) between the following pairs of parameters: Ca2 and Mg2. (R=0.83; Na+ and K+ (R=0.95); (Na2+Mg2) and Cl (R = 0.92); (Na2 + K2) and Ca2 (R=0.96); pH and Cr (R = 0.87). Moreover. the electrical conductivity shows a positive correlation (p<0.05) with the concentrations of K+ (R = 0.97); Na+ (R = 0.96); Ca2+ (R = 0.93); Mg2+ (R = 0.82); Fe2+ (R = 0.85); Cl (R = 0.91) and TDS (R = 0.98). On the other hand, the conductivity shows a negative correlation with SO42 (R = 0.78). Corroborating evidence was provided from the geoelectrical imaging data which Indicate that the thickness of the waste dump ranges between about 2m to 17m, while its resistivity is low at between 4 and 8ohm-m. The low resistivity is due to the presence of leachate emanating from the site and this has also polluted the surface and ground-waters in the Immediate delineation of the limits of the probable polluted zone. 1 results 1
- Variation in chlorophyll-a 1 results 1
- X-ray examinations 1 results 1
- developing country 1 results 1
- ischemic stroke 1 results 1
- nutrients 1 results 1
- phenotyping 1 results 1
- primary productivity 1 results 1
- reporting software intracerebral hemorrhage 1 results 1
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