An information-theoretic approach to interactions in images.

In this paper it will be argued that the notion of interactions in images is closely related to that of entropy associated with an image, and it will be shown that interactions make processing of the information coming from the retina computationally less expensive. A procedure will be presented, based on the evolution of joint entropy across different scales, to gauge the contributions of different types of interactions to the structure of the images.     

Subpopulation analysis of human granular lymphocytes: associations with age, gender and cytotoxic activity

Levels of human blood granular lymphocyte subpopulations were enumerated in 105 healthy donors ranging in age from 0 to 79 years. Using double-label immunofluorescence, subpopulations of granular lymphocytes were enumerated as follows: Leu7+Leu2+, Leu7+Leu3+, Leu7+11-, Leu7+77+ and Leu7-Leu11+. The proportion of cells with granular lymphocyte morphology was determined by Giemsa staining. Natural killer (NK) cell activity against K-562 cells and lymphokine-activated killer activity against non-cultured melanoma cells were examined in parallel. Levels of total Leu7+ and Leu11+ cells increased with age (p = 0.0001) and were higher in males than females (p = 0.001). The total number of cells with granular lymphocyte morphology had an age-related increase (p = 0.001), but were not significantly higher in males than in females (p = 0.07). There was no selective increase in one granular lymphocyte subpopulation versus another since the Leu7+Leu11- (p = 0.0001), the Leu7+Leu11+ (p = 0.0001), the Leu7+Leu2+ (p = 0.0001) and the Leu7+Leu3+ (p = 0.0004) all had similar age-related increases. The one exception was the Leu7-Leu11+ (p = 0.1) granular lymphocyte subset which was low in the first decade of life but had reached maximum levels in the second decade. NK cell activity against K-562 cells was moderately increased with age (p = 0.06) with males and females exhibiting comparable activity. In contrast. lymphokine-activated killer cytotoxicity of non-cultured melanoma cells was similar in all age groups. NK cell activity was highly correlated with levels of morphologically defined granular lymphocytes (p = 0.005) and moderately with total Leu11+ cells (p = 0.06) but not with other subpopulations of granular lymphocytes.     

An analysis of the genetics of schizophrenia

Abstract

Two samples of unplanned and planned children, matched for education, were compared for emotional disturbance on three different instruments. Unplanned children scored consistently higher, in some cases significantly so, particularly among the lower classes. In the second sample, mothers were also compared for neuroticism and for parental attitudes. Mothers of unplanned children scored higher, but not significantly so. No differences in maternal attitudes of rejection and protection were found. In the second study, unplanned children came from significantly larger families than did planned children. It is postulated that the greater the adversity of circumstance of the family, the more negative the effects of unplanned status will be on emotional adjustment.     

Breast cancer,lactation, and genetics

Abstract

A review of mortality rates from breast cancer in several nations indicates that most Caucasian populations have higher rates than do most non‐Caucasian. The only environmental factor shown to affect breast cancer rates consistently is parity, and its mechanisms of actuation are unknown. The higher risks of breast cancer among relatives of patients are reviewed, and a multifactorial genetic control is assumed in which the effects of genetic and environmental factors may be in part additive. While genetic effects are evident in both breast cancer and lactation, it is not clear whether they depend on two distinct sets of genetic factors or on a single set. Assuming that the higher frequencies of breast cancer in Caucasian populations are in some way associated with abnormal genetic factors in hypolactation, the hypothesis is suggested that their rate of elimination by natural selection might have become relaxed or diminished in remote prehistoric times only in Caucasian populations through their widespread development of domestic animal milk as an artificial infant food. Relaxed selection of genetic factors for hypolactation might have caused them to accumulate among Caucasian populations in sufficient frequencies to produce appreciably higher rates of breast cancer in these populations today, even where breast‐feeding is the rule.     

An analysis of the genetics of schizophrenia

Abstract

Data on the inheritance of schizophrenia indicate that both genetics and environment contribute importantly to the manifestation of the disease. However, heterogeneity of the data makes an accurate analysis very difficult. In this paper, a crude analysis of a threshold model, using a polygenic or a single gene hypothesis, shows that both are in approximate agreement with the data. Though argument about genetic models seems futile when virtually any model can account for the data, the single gene hypothesis is unavoidably more attractive at this stage. If a single gene is involved, the allele predisposing toward schizophrenia should be considered as essentially, though not entirely, recessive; all genotypes would be strongly affected by unknown environmental factors; and even some genetically normal individuals would manifest the disorder.     

The genetics of breast cancer, population and familial research and segregation analysis

The data on clinico-genealogy studies of 1046 probands with breast cancer and their relatives are presented. The nature of inheritance corresponded to the Mendelian model. As to other families, there is no strong evidence for the monogene model both with complete and incomplete penetrance of mutant homo- and heterozygotes. Penetrance of homozygotes was 7.9-30.5%, this being 2.0-7.3% for heterozygotes. The conclusion is drawn that it is necessary to consider the regularities of inheritance of breast cancer in the light of the multifactorial model.     

Livestock production,age, and gender among the Keiyo of Kenya

This article is based on a study of time allocation and decision making patterns among the Keiyo in three ecological zones of Elgeyo-Marakvet District, Kenya. It finds that age and gender are important factors to consider when examining livestock production among African smallholder farmers. This is especially true where males are absent from home for wage labor. In these situations women, young males between the ages of 6–15, and persons of both sexes aged 65 and over spend considerable amounts of time engaged in livestock-related activities. These women are also more actively involved in decision making concerning the marketing of milk. The results indicate that there is a definite need to consider the contributions of these other persons when efforts are being made to improve elements of the livestock sector.     

Canine genetics comes of age

The dog, as human's favored companion, is unique among animal species in providing new insights into human genetic disease. In this review, we will discuss both the breed and the population structure of dogs and why that makes canines amenable to genetic studies. We will review the current state of the map and discuss the particular disease states in which canines stand to make the greatest contribution to medical genetics.     

The effect of gender and age on growth hormone replacement in growth hormone-deficient patients.

We analyzed the effect of growth hormone replacement therapy (36 months) analyzed at a dose adjusted to maintain serum insulin-like growth factor-I level between the median and the upper end of the age-related reference range on bone mineral density, body composition, and carbohydrate metabolism with respect to gender and age in 20 adult patients (9 women, 11 men, mean age: 43 years, range: 21-61 years). The lumbar and femoral T-score was increased after 12 and after 18 months of therapy respectively in men (p < 0.001 and p = 0.002), but did not changed significantly in women. The increase of femoral T-score was greater in young men (< or = 45 years, n = 6) than old men (> 45 years, n = 5, p < 0.001). Body fat was lower in men than in women after 6 months (p = 0.002). The waist/hip ratio only decreased in women (p = 0.044). The waist circumference decreased in both genders after 6 months of therapy (p < 0.001), but more markedly in females than in males (p < 0.05). The sum of skinfold thicknesses was reduced in males after 6 months of therapy (p < 0.001). Changes in body composition parameters measured were independent of age. The glycosylated hemoglobin increased without sex or age difference after 12 months of initiation of therapy (p < 0.001), but fasting glucose and insulin levels did not change during the therapy. Our results indicate that the effect of growth hormone replacement on bone mineral content in adults is age- and gender-dependent, gender dependent on body composition, but independent of age and gender on carbohydrate metabolism.     

Bone quality assessment in individuals of different age, gender and body constitution

The concept of bone quality describes the sets of the characteristics of the osseous tissue that influence bone strength. The aim was to explore the influence of anthropometric parameters and age on the parameters of the bone architecture and bone mineral properties in the lumbar vertebral bone of men and women. Vertebral bone samples underwent bone histomorphometry, bone densitometry and atomic absorption spectrometry. Men have greater values of the bone volume and thicker bone trabeculae in relation to women, which indicates that vertebral bone architecture is better preserved in men than in women. Age is the best predictor of changes that affect bone architecture and bone mineral properties. Bone mineral density value and calcium concentration are both negatively predicted by age, but positively predicted by body mass index. Such result supports the opinion that low body mass index is associated with conditions of bone deficit such are osteopenia and osteoporosis.     

Dual diffusions, killed diffusions, and the age distribution problem in population genetics

A method is given for justifying some recent approaches to the definition of the age of an allele in two-allele diffusion-type population genetic models. The method uses the notion of the dual of a diffusion, and introduces naturally an interesting application of killed diffusions. Many results in the literature are shown to be special cases of this approach.