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Abstract  

Radon activity concentrations of 1077 homes were surveyed in two villages of Northern Hungary to obtain the yearly averages. The distribution of indoor radon activity concentrations covered a wide range. Cancer incidences of all the 2680 inhabitants for the last 30 years were also studied in these villages in order to establish a possible correlation with radon exposure. The methods applied in the analysis allow to draw up statistically supported statements concerning the relative cancer risks of different radon level groups. The results show that among non-smoking middle-aged women the frequency of cancer, regardless to tumor types, is lower for those who live in residential radon activity concentrations of a level between 110 and 185 Bq.m-3 compared to those living in radon levels outside this range. A minimum value in the cancer frequency exists at a level of significance p<0.008 (determined with the help of Fisher's test). In general, the present study corroborates the outcome of other studies demonstrating the existence of a biopositive effect, and suggests a wider concept of radon health effects.

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Abstract  

This article analyses the long term incidence of cancer disease in the vicinity of nuclear power plant at Jaslovské Bohunice. The data on the incidence of cancer were summarized by year and by regional district for men and women separately. The main study region was the district Trnava with the districts Nitra and Levice used as a reference teritory. The actual figures are from 1968 till 1990 with a trend calculated up to the year 2000. Mortality was evaluated from the point of view of the percentage of premature deaths and the potentially lost years of life. This analysis was made for a period from 1980 till 1990 for men and women separately for each municipality in the Tmava district. Neither a higher incidence of cancer nor an accelerated dynamics of cancer formation was found in the vicinity of nuclear power plant. Mortality is therefore uniform within the whole Trnava district and no exceptional situation was found within the regional continuity.

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Summary  

It has been observed that among the seven municipalities of the Island of Krk the three in the central part of the island have increased disease incidence rates for the five groups of diseases: (a) neoplasm, (b) diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism, (c) endocrine, nutritional and metabolic diseases, (d) mental and behavioral disorders and (e) diseases of the circulatory system. One of the etiological factors is assumed to be the influence of the geochemical environment. The average element concentration values of six trace elements (Mn, Fe, Ni, Cu, Zn and As) for the geochemical environment in the individual municipalities were determined by XRF analyses of soil, plant, potable water and hair samples. The data on disease incidence rates for the individual municipalities, from 1997 to 2001, have been obtained from the Public Health Institution in charge of monitoring population health on the island. Diseases' groups have been defined by the WHO methodology. The GPS-GIS methodology was used to obtain maps of trace elements in different matrices and disease incidence distributions. Data analyses were performed by multivariate statistical methods (principal component analysis and cluster analysis). It has been shown that the concentration levels of the elements could be related to disease incidence rates.

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Abstract  

Neutron Well Coincidence Counting has been explored as a non destructive assay technique for determining the percentage of PuO2 in blended mixture of UO2 and PuO2 powders. The method has been applied to MOX blends having PuO2 content varying from 0.4 to 44% for both thermal and fast reactors. The use of Neutron Well Coincidence Counting technique is validated as a process control step for determining PuO2 content in the fabrication of MOX fuel by comparing it with chemical analysis of sintered pellets. It has been used at Advanced Fuel fabrication Facility, Bhabha Atomic Research Centre, Tarapur during the manufacture of MOX fuel of various types for thermal and fast reactors.

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Introduction Cutaneous melanoma is the most malignant tumor of the skin and its incidence is on the rise [ 1 , 2 ]. There is convincing evidence from epidemiologic studies that endogenous (genetic markers, skin type) and

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Cocaine is the second most illicit drug worldwide. Levamisole, an anthelminthic drug, has been identified as a cocaine adulterant in the United States since the last decade. Now, its presence has increasingly been discovered in street cocaine samples seized in India. Recently, it has been observed in many street cocaine samples seized by investigation agencies in India. Due to the incidence of toxicity caused by this contamination which has been increasing rapidly since 2002, it is important to understand the chemical separation, identification, and quantification of this drug. In the present study, an attempt has been made to develop a new high-performance thin-layer chromatographic (HPTLC) method for the simultaneous discrimination and quantification of levamisole in seized cocaine samples. Chromatography was performed using a pre-coated silica gel aluminum plate as the stationary phase, and the mobile phase cyclohexane–toluene–diethylamine (75:15:10) was able to discriminate between cocaine hydrochloride and levamisole hydrochloride significantly. Densitometric analysis was performed in the absorbance mode at 230 nm. The linear regression analysis of data for the calibration curve showed good linearity over a concentration range of 100–1200 ng per band and 200–2400 ng per band with a regression value of 0.997 and 0.995 for levamisole hydrochloride and cocaine hydrochloride, respectively. The developed method is used to quantify cocaine content as well as to estimate the concentration of adulterant levamisole. The method was validated according to the International Conference on Harmonization (ICH) guidelines and can be used in the identification and quantification of levamisole and cocaine in seized cocaine samples. The present method is simple, reproducible, and repeatable, which can easily be performed in any laboratory.

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Abstract  

The directional response of a scintillation detector to γ-rays has been studied for the full energy peak. The directivity measured has a lower value than that one corresponding to the total spectrum. This behaviour was attributed to the degradation of the peak-to-total ratio with the angle of γ-ray incidence.

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Abstract  

Guangdong Province of China is the highest incidence place of naso-pharyngeal cancer in the world. The concentrations of 19 trace elements in hair of 90 naso-pharyngeal cancer patients in Guangdong Province have been measured by the PIXE technique. By using the Maximum Probable Discrimination Method to distinguish naso-pharyngeal cancer patients from healthy people, we get up to 91.1% validity of differential diagnosis and get some indication that special trace elements participate in carcinogenesis.

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Abstract  

There is currently great interest in iodine as a micro nutrient. Both high and low intakes have been associated with thyroid cancer incidence. Development of dietary iodine monitors is needed to supplement the use of dietary recall methods which have not been well validated for iodine. In this study, 30 pooled urine samples, from ethnic groups on various islands in the South Pacific, were analyzed for iodine using epithermal instrumental neutron activation analysis (EINAA).

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Abstract  

False positive and false negative incidence rates of radiological monitoring data from classical and Bayesian statistical process control chart techniques are compared. The on-line monitoring for illicit radioactive material with no false positives or false negatives is the goal of homeland security monitoring, but is unrealistic. However, statistical fluctuations in the detector signal, short detection times, large source to detector distances, and shielding effects make distinguishing between a radiation source and natural background particularly difficult. Experimental time series data were collected using a 1″ × 1″ LaCl3(Ce) based scintillation detector (Scionix, Orlando, FL) under various simulated conditions. Experimental parameters include radionuclide (gamma-ray) energy, activity, density thickness (source to detector distance and shielding), time, and temperature. All statistical algorithms were developed using MATLAB™. The Shewhart (3-σ) control chart and the cumulative sum (CUSUM) control chart are the classical procedures adopted, while the Bayesian technique is the Shiryayev–Roberts (S–R) control chart. The Shiryayev–Roberts method was the best method for controlling the number of false positive detects, followed by the CUSUM method. However, The Shiryayev–Roberts method, used without modification, resulted in one of the highest false negative incidence rates independent of the signal strength. Modification of The Shiryayev–Roberts statistical analysis method reduced the number of false negatives, but resulted in an increase in the false positive incidence rate.

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