• Environmental Mutagens and Carcinogens
• /
• v.19 no.2
• /
• pp.95-101
• /
• 1999

Risk Assessment is an important area in toxicology and the methodology for risk assessment has been developed. Mathematical models used for risk assessment include one-hit multi-hit, two-stage, probit logistic, multistage, and linearized multistage models. For the assessment of exposure dose, environmental monitoring has been applied, but it has limitation to accurately assess exposure level because the levels in the air, water, foods, and soil may vary depending on time of sampling. In addition, humans can be exposed to various sources of exposure and thus it will be impossible to estimate the total level of exposure in humans by environmental monitoring. To eliminate the limitation of environmental monitoring, a direct measurement of toxic materials or modified biomolecules (called biomarkers) associated with the exposure of toxic materials is needed. Here, scientific basis of biomarkers and future direction have been considered for the assessment of carcinogen exposure and cancer risk in humans.

• Advances in environmental research
• /
• v.6 no.3
• /
• pp.229-240
• /
• 2017

This paper assessed environmental sanitation behaviour of market operators in selected markets in Ibadan, Nigeria. The two largest markets in the study area (Aleshinloye and Bodija markets) were selected for sampling. The selected markets represented the two types of markets; modern and traditional markets. The modern market comprises 3803 shops while the traditional market comprises 5943 shops. Multistage sampling technique was adopted in questionnaire administration. The selected markets were stratified into zones based on the goods sold. Systematic sampling was used in the selection of traders across the markets. 2% of traders were selected for sampling in each category of goods sold making a total of 189 respondents. This comprises 77 of traders from modern market and 112 traders from traditional markets. Descriptive and Inferential statistics were used in analysing the data. Findings revealed poor access to environmental sanitation facilities especially at the traditional market. The study also established poor environmental sanitation behaviour in terms of utilisation of available amenities across both markets. It recommended a synergy of efforts by all environmentally concerned institutions in managing the market environment. It also advocated for the provision of environmental sanitation facilities in markets by, government, market management authorities, traders, Community Based Organizations (CBOs) and Non-governmental Organizations (NGOs). In addition environmental education is imperative while enforcement of environmental regulations in the market and others with similar setting is strongly encouraged.

• Asian Pacific Journal of Cancer Prevention
• /
• v.16 no.17
• /
• pp.7803-7807
• /
• 2015

Opisthorchis viverrini infection is a serious public health problem in Southeast Asia especially in the northeast and north of Thailand. Therefore, a cross-sectional survey using multistage sampling was conducted from the rural communities of Surin province, Thailand, during September 2013 to July 2014. O. viverrini infection was determined using Kato's thick smear technique. Socio-demographic, information resources, and history data were collected using predesigned semi-structured questionnaires. A total of 510 participants completed interviews and had stools collected. Some 32 (6.47%) participants were infected with O. viverrini. The rate was slightly higehr in males (6.61%) than females (6.32%). High frequencies were found in the age groups 61-70 (19.4%) and 71-80 years (19.4%), those involved in agriculture (10.5%), and in primary school (10.3%). The distribution of high infection was found in Tha Tum (16.7%) and Sankha district (16.7%), followed by Samrong Thap (13.3%), Si Narong (13.33%), and Buachet district (13.33%). Chi-square testing indicated that age (61-70 and 71-80 year old), education (primary school) and occupation (agriculture), were significantly associated with O. viverrini infection (p-value<0.05). Of 72.6% participants who had past histories with stool examination, 17.0% of them had been infected with O. viverrini and 43.2% treated with praziquantel. This finding confirmed that O. viverrini is still a problem in Surin province, Thailand, and therefore, interventions are urgently required for mass treatment and health education implementation.

• Smart Structures and Systems
• /
• v.29 no.1
• /
• pp.53-62
• /
• 2022

The deployment of advanced structural health monitoring (SHM) systems in large-scale civil structures collects large amounts of data. Note that these data may contain multiple types of anomalies (e.g., missing, minor, outlier, etc.) caused by harsh environment, sensor faults, transfer omission and other factors. These anomalies seriously affect the evaluation of structural performance. Therefore, the effective analysis and mining of SHM data is an extremely important task. Inspired by the deep learning paradigm, this study develops a novel generative adversarial network (GAN) and convolutional neural network (CNN)-based data anomaly detection approach for SHM. The framework of the proposed approach includes three modules : (a) A three-channel input is established based on fast Fourier transform (FFT) and Gramian angular field (GAF) method; (b) A GANomaly is introduced and trained to extract features from normal samples alone for class-imbalanced problems; (c) Based on the output of GANomaly, a CNN is employed to distinguish the types of anomalies. In addition, a dataset-oriented method (i.e., multistage sampling) is adopted to obtain the optimal sampling ratios between all different samples. The proposed approach is tested with acceleration data from an SHM system of a long-span bridge. The results show that the proposed approach has a higher accuracy in detecting the multi-pattern anomalies of SHM data.

• Journal of the Korean Society of Physical Medicine
• /
• v.18 no.4
• /
• pp.19-27
• /
• 2023

PURPOSE: This investigation in the study aimed to assess to determine proportion and susceptibility makers of sarcopenia in Korean younger female aged 30 to 39 years. METHODS: To address the complex sampling design of Korea National Health and Nutrition Examination Surveys, appropriate individual weights were incorporated into the analysis. The data employed a stratified, clustered, multistage probability sampling design. A total of 2,098 participants were enrolled and categorized into two groups based on their skeletal muscle mass index scores. One hundred and twenty-four individuals were placed in the sarcopenia group, while 2,024 were allocated to a normal group. The study examined various markers as variables, including age, height, weight, body mass index waist circumference, skeletal muscle mass index, systolic and diastolic blood pressure, fasting glucose, triglyceride, and total cholesterol levels, and smoking and drinking habits. RESULTS: The study found that proportion of sarcopenia in this population was 3.78% (CI: 2.89-4.94) in sarcopenia group and 96.22% (CI: 95.06-97.11) in normal with weighed values. Several susceptibilities including height, weight, BMI, waist circumference, diastolic blood pressure, and total cholesterol levels were risk factor for sarcopenia (p < .05), exhibited significant differences between the sarcopenia and normal groups. CONCLUSION: This investigation provides the proportion of sarcopenia and identifies relevant susceptibility markers among community dwelling younger women in Korea.

• Communications for Statistical Applications and Methods
• /
• v.10 no.2
• /
• pp.553-566
• /
• 2003

In many cases, the measurement error variances may be functions of the unknown true values or related covariates. This paper considers design-based estimators of the parameters of these variance functions based on the within-unit sample variances. This paper devotes to: (1) define an error scale factor $\delta$; (2) develop estimators of the parameters of the linear measurement error variance function of the true values under large-sample and small-error conditions; (3) use propensity methods to adjust survey weights to account for possible selection effects at the replicate level. The proposed methods are applied to medical examination data from the U.S. Third National Health and Nutrition Examination Survey (NHANES III).

• Journal of Preventive Medicine and Public Health
• /
• v.32 no.2
• /
• pp.183-190
• /
• 1999

Objectives: The purpose of this study is to analyse factors related to the health promotion behavior or the basis of theory of reasoned action(TRA). Methods: 509 residents in the city of Kyunggi-do were selected through multistage random sampling. A structured questionnaire was developed or the basis of Triandis model and collected by interviewing. Results: Expectation toward act and social normative influence and age showed significant relationship to health promotion behavior, Also, facilitating factors, affective attitude, education level are indirectly related to health promotion behavior. Conclusions: The result suggest that TRA is useful in understanding the mechanism of health promotion behavior.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.21
• /
• pp.9499-9503
• /
• 2014

This study aimed to examine the relationship between body image satisfaction and breast self-screening behaviors and intentions. The sample for this cross-sectional study consisted of 842 female university students who were recruited from a number of public and private universities. Data were obtained between the months of November and December, 2013, using multistage random cluster sampling. Main research variables were breast cancer screening behavior and intentions, demographic factors, and the total scores on each of the Multidimensional Body-Self Relations Questionnaire (MBSRQ-Appearance Scales) subscales. Results of multivariate analysis showed that having higher satisfaction and more positive evaluation of appearance were related to having performed breast self-examination more frequently in the last year and intending to perform breast self-examination more frequently in the next year. Longitudinal research can potentially provide detailed information about overall body image satisfaction and breast cancer screening behavior among various communities.

• 한국데이터정보과학회:학술대회논문집
• /
• 2003.05a
• /
• pp.1-14
• /
• 2003

In man cases, the measurement error variances may be functions of the unknown true values or related covariate. In some cases, the measurement error variances increase in proportion to the value of predictor. This paper develops estimators of the parameters of a linear measurement error variance function under stratified multistage random sampling design and additional conditions. Also, this paper evaluates and compares the power of an asymptotically unbiased test with that of an asymptotically biased test. The proposed method are applied to blood sample measurements from the U.S. Third National Health and Nutrition Examination Survey(NHANES III)

• Journal of Preventive Medicine and Public Health
• /
• v.21 no.2 s.24
• /
• pp.251-266
• /
• 1988

This study was planned in order to investigate coal miners' recognition and attitude toward pneumoconiosis, and its realtionship with related behavior for prevention of pneumoconiosis. Study object was coal miners in Kangneung area, sampled by multistage random proportional sampling. Sample size was 13% of total coal miners in Kangneung area. The results were devided into three parts: (1) descriptive results presented percent distribution, (2) reclassification of knowledge, experiences, and attitude by factor analysis, (3) prediction of health behavior for prevention of pneumoconiosis by discriminant analysis. Knowledge, experiences, and attitude toward pneumoconiosis were classified into nine factors. Knowledge about pneumoconiosis were broken down to two factors and attitude to four factors, and valence, perceived severity were classified into each one factor. According to demographic, socioeconomic characteristics, and factors of knowledge, experiences, attitude about pneumoconiosis, about 62% of behavior of wearing respiratory protector was correctly discriminated. And by the same methods, about 81% of behavior of hospital visit at respiratory symptoms; cough, sputum, chest pain etc. was discriminated correctly.