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J Dolejs

Publications and source records attributed to J Dolejs.

8 recordsLinked to original sources
PubMed2003

The weekly measurement deviations of indoor radon concentration from the annual arithmetic mean.

The difference between weekly measurements and the annual arithmetic mean of radon indoor concentration CRn,Indoor was studied in the Czech Republic. The deviations were analysed for 1537 weekly measurements which were consecutively obtained in 29 rooms over a period of 1 year and the annual arithmetic mean was calculated for each particular room. The relationship of the deviations to three meteorological parameters (i.e. outside temperature, atmospheric pressure, and weekly rainfall) and to the sequential number of a calendar week was studied. The effect of atmospheric pressure and weekly rainfall was not significant. The deviation between a weekly measurement and the annual arithmetic mean depended significantly on outside weekly average temperatures. If the average outside weekly temperature was below 10 degrees C, the radon concentration was systematically higher than that of the annual arithmetic mean. The deviation variability was lower up to a temperature of 10 degrees C. If the weekly average outdoor temperature was higher than 10 degrees C, the uncertainty of a weekly measurement of radon concentration was also higher.

Air Pollutants, Radioactive↗
PubMed2001

Theory of the age dependence of mortality from congenital defects.

A theory is presented, based on the evidence that the congenital defect of an individual is at one of many different levels. It is supposed that the individual mortality risk from congenital defect is lognormally or normally distributed in the population. The relationship between childhood mortality from seven congenital defects and age is described. It uses data from the US during the period 1979-1991. Mortality from five congenital defects is inversely proportional to age. Mortality from two congenital defects is inversely proportional to the second power of age. The presented theory explains these two observed types of mortality decline with age. Childhood mortality from some infectious diseases is also inversely proportional to age during childhood in different populations. It follows from this theory that the death from these infectious diseases up the age of 10 years may be caused by a hidden congenital frailty.

Aging↗
PubMed2000

Postnatal mortality from meningococcal infections during the period 1950-1991 in the US.

Research has been conducted on the relationship between postnatal mortality from meningococcal infections and age, using data from the US during the period 1950-1991. The logarithm of mortality caused by meningococcal infections fell linearly with the logarithm of age, during the interval of 1-30 years for men and women in the US. The slope of this straight line is equal to -1. The mortality from meningococcal infections is inversely proportional to the age in the US. The risk of death at age 2 is one half of the risk at age 1, at age 3 it is one third of the risk of death at age 1, etc. up to the age of 30 in the US. The same decline was observed for the risk of death from congenital anomalies and pneumonia.

Adolescent↗
PubMed2000

Postnatal mortality from pneumonia.

Research has been conducted on the relationship between postnatal mortality from pneumonia and age, using data from the USA, Japan, former Czechoslovakia, Italy, Portugal and the UK during the period of 1979-1993. The logarithm of mortality caused by pneumonia fell linearly with the logarithm of age, during the interval of 1-10 years. This linear log-log dependence corresponds to the two-parametrical Weibull distribution, if the slope is greater than -1. However, the logarithm of mortality from pneumonia declined with the slope equal to -1. The mortality from pneumonia is inversely proportional to the age. The risk of death at age of 2 is one half of the risk at the age of 1, at the age of 3 it is one third of the risk of death at the age of 1ellipsis, etc. up to the age of 10. We assumed that no subpopulation susceptible to pneumonia exists and the risk of death from pneumonia applies in whole population. Consequently, there was applied another distribution function described at this paper.

Adolescent↗
PubMed1998

The size of the subpopulation susceptible to malignant neoplasm of the brain.

A decline of mortality dependence on age from the exponential relation is observed for some diseases. This decline could be explained by the existence of an inherently susceptible population subset which is depleted faster than the general population. A model is presented which describes this situation using malignant neoplasm of the brain. The model assumes that only those who are members of the subset can die of malignant neoplasm of the brain. This model was used to fit the actual mortality curve of malignant neoplasm of the brain for women and men in the USA in 1979. The size of this subset equalled one of two parameters used to fit the actual data. The decline of mortality dependence upon age can be explained by this model. The size of the subpopulation is 0.390% for men and 0.417% for women. The theoretical curves resulting from that model capture the actual mortality due to malignant neoplasm of the brain.

Adolescent↗
PubMed1998

[Mortality in congenital abnormalities in relation to age].

The mortality dependence on age after the birth was observed for dominant causes of death in the USA, Japan and former Czechoslovakia for the period 1979-1991. The logarithm of mortality of following causes decrease linearly with logarithm of age at the interval 0-10 years: all, all without accidents, congenital anomalies of heart and circulatory system, spina bifida and hydrocephalus, diseases of the nervous system, other diseases of the respiratory system. The linear area is up to the age of 45 years for Spina bifida and hydrocephalus in the USA. This linear dependence in log-log scale corresponds to the Weibull distribution in case the slope is more than -1. However, the logarithm of mortality of Congenital anomalies decreases in the logarithm of age with the slope of -1. The number of death of congenital anomalies decreases in the logarithm of age with the slope -1, too. The number of death in one year corresponds to the failure density function. The mortality of congenital anomalies is described using another distribution function which is not Weibull function. This new distribution is defined at this paper. The number of death of congenital anomalies in one year is inversely proportional to the age of dead. This phenomenon can be interpreted that the lifetime is determine by the level of malformation at the moment of the birth. The number of people in particular level of congenital anomalies is inversely proportional to the lifetime.

Adult↗
PubMed1997

The extension of Gompertz law's validity.

The interval 35-85 years is mostly considered as the range of Gomperz law's validity. Looking at the spectrum of causes of death for the interval 10-30 years we find that its main share is caused by various accidents independent of age. These accidents result in the increase and following plateau of the total mortality curve over the age of 15 years. When the number of deaths from age independent causes (accidents, violence, suicide, accidental falls, etc.) is subtracted from the total number of deaths the linear area begins before the age of 20 years. The linear regression of the logarithm of mortality without accidents was performed for the age interval 20-84 years for six populations (men and women in the US in 1989, in Japan in 1990 and in former Czechoslovakia in 1990). Furthermore, the mortality curves of some causes important at the interval 0-15 years were inspected. Unlike other causes, births do not affect the disposition of children to die of malignant neoplasm of the brain and malignant neoplasm of lymphatic and haemopoietic tissue.

Adolescent↗