Models of Neurotoxicity: Extrapolation of Benchmark Doses in Vitro

In risk assessment, no observed exposure level (NOAEL) and benchmark dose (BMD) are usually derived either from epidemiological studies in humans or from animal experiments. In many in vitro studies, concentration-effect/response curves have been analyzed using different mathematical models finalized to the identification of EC50. In the present article, we propose a model to fit dose-response curves in vitro. The BMD approach has been used to compare the cell viability (MIT assay) of different rat (C6 and PC12, glial and neuronal, respectively) and human cell lines (D384 and SK-N-MC, glial and neuronal, respectively) after 24-hour exposure to the following neurotoxic substances: manganese chloride (MnCl2), methyl-mercury (Me-Hg), and the enantiomers of styrene oxide (SO). For all rat and human cell lines, the potency of the examined compounds was: MnCl2 < S-SO < R-SO < Me-Hg. A preliminary comparison with in vivo toxicity data for these substances gave rise to consistent results. Whereas a reasonable agreement between in vitro and in vivo data has been found for Mn and styrene oxide, a wide scatter of LOAEL has been reported for Me-Hg and these appear to be either much higher or lower than the BMD for the MIT assay we observed in vitro.     

Dynamic factor models

Summary Factor models can cope with many variables without running into scarce degrees of freedom problems often faced in a regression-based analysis. In this article we review recent work on dynamic factor models that have become popular in macroeconomic policy analysis and forecasting. By means of an empirical application we demonstrate that these models turn out to be usefu in investigating macroeconomic problems.     

Social policy options and fuel poverty

The concept of ‘fuel poverty’, the inability to afford adequate warmth at home has become a focus for social policies in recent years. Increasing numbers of households dependent on social security and the likelihood that fuel will become more expensive mean that the existing problem of fuel poverty may become even greater. The data on fuel expenditure and related variables from three national surveys are used to evaluate various policy options for relieving fuel poverty. Three policies for increasing incomes to pay for fuel costs are considered, increasing benefits, introducing a fuel allowance or extending the existing scheme of additional heating requirements. The policies for reducing fuel expenditure are also considered, restructuring tariffs, changing payment methods and conservation measures. The case is made for priority to be given to an advice and information campaign and a conservation programme aimed at poor households who are unable to respond to existing price signals and grants.     

FAMILY INTERVENTION IN A CASE OF MULTIPLE PERSONALITY

The authors report a case of multiple personality in which therapy was directed at the marital couple, rather than focusing on the multiple personality per se. The symptoms of the individual are seen as a disturbance in the family homeostasis and were treated from that standpoint. The functions of the symptom in the areas of impulse discharge, superego operation, boundaries of closeness-distance, and self-object representations for the couple and family are discussed.     

Long-term economic consequences for women of delayed childbearing and reduced family size

Using data from the Panel Study of Income Dynamics, this study explored the association among delayed childbearing, completed family size and several measures of the economic well-being of women age 60 and older in 1976. By retirement age women who bore their first child at age 30 or older are significantly better off economically than either average-age childbearers or the childless. Economic well-being also appears to be related to family size among late childbearers. At retirement age the delayed childbearer with only one or two children appears better off than all other women. Thus, late childbearing and small family size appear associated with the highest standard of living for these women. This study also relates the experience of this early cohort of women to that of more recent birth cohorts.     

INTERVENTION PLANNING FOR THE FAMILY OF THE AUTISTIC CHILD: A MULTILEVEL ASSESSMENT OF THE FAMILY SYSTEM*

The clinician working with the family of an autistic child may need to assess the family at several levels. The first level requires an assessment of the behavioral deficits and excesses of the child. The next level examines the family in terms of their behavioral skills and the impediments that occur when they implement behavior change programs. The third level involves assessing the family unit to identify obstacles to change. While many well-functioning families may be stressed by the crises that arise in raising an autistic child, other families are predisposed to dysfunction regardless of the presence of the child.     

Job creation: New work for women?

The movement of some women into self employment is considered in this paper. It is argued that if this movement is to be successful, and thus have any influence on the equality of employment opportunities, then it is necessary for the business ventures involved to be run strategically rather than operationally. It is also argued that there must be greater scope and encouragement for innovation in this area, otherwise there is a danger of mirroring, in new business formation, the structure of inequality that applies to the formal, and declining, structure of current employment. Finally, the paper examines the need for women's entrepreneurial ventures to be better accepted by and integrated into the wider social fabric. The potential sources of stress and of satisfaction in women's self employment are noted.     

Relationship satisfaction and sexual satisfaction: a longitudinal study of individuals in long-term relationships

This study examined the association between relationship satisfaction and sexual satisfaction over time to provide evidence about possible causal explanations for the association between two variables. Eighty-seven individuals in long-term relationships completed measures of sexual satisfaction and relationship satisfaction at 2 times 18 months apart. There was only limited evidence, based on exploratory analysis, to support either the hypothesis that changes in a relationship satisfaction lead to changes in sexual satisfaction or the hypothesis that changes in sexual satisfaction lead to changes in relationship satisfaction. However, sexual satisfaction and relationship satisfaction wer found to change concurrently. The quality of intimate communication accounted for part of the concurrent changes in relationship satisfaction and sexual satisfaction. I discuss the results in terms of the need to develop more complex models depicting the longitudinal associations between relationship satisfaction and sexual satisfaction.