The role of gender-related processes in the development of sex differences in self-evaluation and depression.

This paper examines gender socialization processes during childhood that may contribute to a higher incidence of depression or depressive symptoms in females than in males. It is argued that because of the actions of socialization agents and the impact of gender stereotypes on a child's construction of gender identity, girls may exhibit higher levels of self-evaluative concerns that increase vulnerability to depression. Indeed, a review of the literature on sex differences in self-evaluation suggests that girls may be more susceptible than boys to self-evaluative concerns, particularly as reflected in lower expectations for future success, more maladaptive causal attributions for success or failure outcomes, and negative behavioral and evaluative reactions to failure. Moreover, an examination of the literature on sex differences in depressive symptoms leads to questions about previous conclusions that girls do not exhibit higher levels of depressive symptoms prior to adolescence. Finally, we present some recent original data that support the contention that sex differences in vulnerability to depression may be evident prior to adolescence.

Retention of inhaled 2-methylfuran and 2,5-dimethylfuran.

The respiratory tract retention of 2-methylfuran and 2,5-dimethylfuran in the dog have been studied as part of a broad investigation of substances found in the vapor phase of cigarette smoke. Retention of 2-methylfuran tended to be higher that that of 2,5-dimethylfuran in the upper, lower and total respiratory tract. Uptake of 2-methylfuran ranged from 63-88% in these regions while it was only 53-62% for 2,5-dimethylfuran. Retention of 2,5-dimethylfuran was lower than any of the other compounds studied. However, the majority of either compound will be absorbed by the respiratory tract when inhalation occurs.

Respiratory retention and acute toxicity of furan.

The respiratory tract retention of furan has been studied in dogs as part of a broad investigation of compounds found in the vapor phase of cigarette smoke. The LD50 of furan has also been determined in mice and rats and the LC50 in mice. Respiratory uptake of furan was between 90 and 95%, varying inversely with the ventilatory rate. Retention was not affected by tidal volume changes but was directly related to concentration inhaled. Intraperitoneal LD50 values were 5.2 mg/kg for rats and 7.0 mg/kg for mice. The LC50 for mice was 0.12 microgram/mL. These results indicate the high toxicity of furan and that it is readily absorbed by the inhalation route.

Respiratory retention of inhaled toluene and benzene in the dog.

This study deals with the inhalation of toluene and benzene found in the vapor phase of cigarette smoke. Determined in this study were the uptake of each substance by the total respiratory tract and by the upper and lower portions under varying conditions of ventilatory rate, tidal volume, and concentration inhaled. Retention by the total tract of toluene fell within the range of 91-94% at all ventilatory rates seen, indicating no relationship between rate and retention. With benzene, total tract retention varied from 88 to 68% with an inverse relationship between retention and rate apparent. This relationship was seen in all types of experiments conducted with benzene. Upper tract retention revealed an uptake of about 89% for both one- and two-way experiments with toluene. In the benzene experiments retention varied from 80 to 61% and from 81 to 63% in the one- and two-way procedures, respectively. Mean lower tract retention was 90% with toluene at all ventilatory rates considered. Benzene retention varied from 74 to 61% as the rate increased from 6 to 18 inhalations/min.