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61.
The skin is a route of exposure that needs to be considered when conducting a risk assessment. It is necessary to identify the potential for dermal penetration by a chemical as well as to determine the overall importance of the dermal route of exposure as compared with inhalation or oral routes of exposure. The physical state of the chemical, vapor or liquid, the concentration, neat or dilute, and the vehicle, lipid or aqueous, is also important. Dermal risk is related to the product of the amounts of penetration and toxicity. Toxicity involves local effects on the skin itself and the potential for systemic effects. Dermal penetration is described in large part by the permeability constant. When permeability constants are not known, partition coefficients can be used to estimate a chemical's potential to permeate the skin. With these concepts in mind, a tiered approach is proposed for dermal risk assessment. A key first step is the determination of a skin-to-air or skin-to-medium partition coefficient to estimate a potential for dermal absorption. Building a physiologically-based pharmacokinetic (PBPK) model is another step in the tiered approach and is useful prior to classical in vivo toxicity tests. A PBPK model can be used to determine a permeability constant for a chemical as well as to show the distribution of the chemical systemically. A detailed understanding of species differences in the structure and function of the skin and how they relate to differences in penetration rates is necessary in order to extrapolate animal data from PBPK models to the human. A study is in progress to examine anatomical differences for four species.  相似文献   
62.
Veenhoven (1994) contrasted hypotheses of whether happiness is a trait or state, concluding that it is a state variable. This article critiques the conceptual foundation of Veenhoven's paper, and examines technical deficiencies in his review of evidence. Based on previous findings and new analyses, we conclude that happiness has both traitlike and statelike properties, but that individual differences in happiness endure despite its situational reactivity, and explain greater variance than situational effects.  相似文献   
63.
Mortality data are often gathered using 5-year age groups rather than individual years of life. Furthermore, it is common practice to use a large open-ended interval (such as 85 and over) for mortality data at the older ages. These limitations of the data pose problems for the actuary or demographer who wishes to compile a full and accurate life table using individual years of life. The author devises formulae which handle these problems. He also devises methods for handling mortality during the 1st year of life and for dealing with other technical problems which arise in the compilation of the full life table from grouped data.  相似文献   
64.
This paper examines the situation and problems of migration on family structure, with emphasis on family reunification. The study is based on conditions and practices in Western Europe and Mediterranean countries relating to temporary labor migration. Most migrant workers have no intention of settling permanently and return to their country within a few years. The International Labour Office estimated in 1974 that at least 1/2 the migrant workers in Western Europe live without their families. Generally, migrants send for their families only when they are employed, earning adequate wages, and have adequate housing. Some reasons why migrants live apart from their families include 1) the receiving country discourages family immigration because it does not coincide with the economic necessities of migration policy and 2) some sending countries discourage it to ensure that the migrant worker returns to his own country. The main danger arising from family separation is that it frequently leads to the break up of the family. The leading European authorities recognize as a fundamental right the freedom of a migrant worker and his family to lead a normal family life in the receiving country. The author outlines the conditions for admission for residence and employment of migrant spouses and children for the Federal Republic of Germany, France, Belgium, Switzerland, the Netherlands, Sweden, Norway, Austria, Luxembourg, and the United Kingdom. All countries require that the head be in regular employment for some time and be able to provide his family with suitable housing. Other problems concerning the arrival of migrant spouses and children include 1) acquiring employment and social information and counseling, 2) education of children, 3) obtaining vocational training and adaptation and 4) achieving entitlement to social security benefits. The effects of migration in the family context in sending countries include 1) providing activities for migrants to maintain cultural links with their countries of origin and 2) acquiring the nationality of the receiving countries. Countries should facilitate the admission to employment of migrant spouses and children, by maintaining provisions for the reuniting of families and imposing no limits on admission to residence; and 2) by overcome obstacles to admission to employment, by observing existing recommendations. In conclusion, governments should give family cohesion 1st priority, regardless of regulations.  相似文献   
65.
Individual preferences inconsistent with personal welfare caused neither by ignorance nor by a positive consideration for the welfare of others are defined as (welfare) irrational. Sources of irrationality (rigid adherence to moral principles, excessive fear of danger, excessive tempetation of pleasure, revenge, inertia, faulty telescopic faculty, the fallacy of diminishing marginal utility of utility, etc.) are discussed. An evolutionary explanation of irrationality is suggested and some implications for individual decision and social policy indicated.I am grateful to two anonymous referees for comments.  相似文献   
66.
To assess the validity and clinical utility of the marital inventory ENRICH, a discriminant validity study was conducted using a national sample of 5039 married couples. The sample was randomly split in order to form a cross-validation group. ENRICH is a multidimensional scale and two types of analysis were conducted to assess the value of these various scales. Results from discriminant analysis indicated that using either the individual scores or couples' scores, happily married couples could be discriminated from unhappily married couples with 85–95% accuracy. These results were cross-validated with a second sample. Using regression analysis, it was clearly demonstrated that background factors account for little of the variance in discriminating happy from unhappily married couples compared to their relationship dynamics, i.e., scale scores. All ENRICH scales except equalitarian roles proved significant, indicating the validity of a multidimensional inventory.  相似文献   
67.
68.
Compliments are often viewed primarily as a linear event in which one person expresses approval or admiration of another. Far less attention has been given to the circular nature of compliments and the manner in which they enhance the positions of both the giver and the receiver of the compliment. Therapeutic compliments have proven to be highly effective means of motivating clients, while at the same time increasing therapeutic leverage. This article proposes that compliments should be purposefully given, and that the type of compliment should vary with the stage of therapy and the intended response of the client to the compliment.  相似文献   
69.
A comparison of cohorts of ever-married Chanaian women suggests evidence of a fertility transition beginning among younger women and select subgroups. Ghana's crude birth rate declined from a high of 50/1000 population in 1970 to 38.8/1000 in 1985. To ascertain whether marital fertility is now being controlled through conscious attempts to lengthen birth intervals, World Fertility Survey data from 1979-80 on the timing of births among different birth cohorts were analyzed. It was hypothesized that, as a result of the influence of Western values that stress independence from parents and the introduction of compulsory education, cohorts of the mid-1950s and 1960s would be more likely to postpone childbearing, more active in the modern sector of the economy, and more accepting of modern contraceptive usage for birth spacing than women in the 1930-39, 1940-49, and 1950-59 cohorts. For the 1940-49 cohort, it took 10.8 months for 25% to have a birth following 1st marriage, 18.7 months for 50% to have a 1st birth, and 27.4 months for 75% to complete this step. By comparison, these figures for the 1955-64 birth cohort were 9.9, 16.7, and 20.5 months, respectively. The significantly shorter (p 0.01) interval between marriage and 1st birth found among younger women in part reflects rising age at marriage; mean age at 1st marriage was 17.9 years for the 1940 cohort and 21.6 years for the most recent cohort. After the birth of the 1st child, recent cohorts were more likely to wait longer for the 2nd birth. For women born in 1950-64, it took 21.8, 36.7, and 44.6 months for 25%, 50%, and 75%, respectively, to reach parity 2. This pattern of lengthened birth interval beyond the 1st birth was apparent at all parities in the youngest cohort and indicates increasing acceptance of contraception among those who have come of age during a period of rapid social change.  相似文献   
70.
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