Exposure Reconstruction for the TCDD-Exposed NIOSH Cohort Using a Concentration- and Age-Dependent Model of Elimination

Recent studies demonstrating a concentration dependence of elimination of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) suggest that previous estimates of exposure for occupationally exposed cohorts may have underestimated actual exposure, resulting in a potential overestimate of the carcinogenic potency of TCDD in humans based on the mortality data for these cohorts. Using a database on U.S. chemical manufacturing workers potentially exposed to TCDD compiled by the National Institute for Occupational Safety and Health (NIOSH), we evaluated the impact of using a concentration- and age-dependent elimination model (CADM) (Aylward et al., 2005) on estimates of serum lipid area under the curve (AUC) for the NIOSH cohort. These data were used previously by Steenland et al. (2001) in combination with a first-order elimination model with an 8.7-year half-life to estimate cumulative serum lipid concentration (equivalent to AUC) for these workers for use in cancer dose-response assessment. Serum lipid TCDD measurements taken in 1988 for a subset of the cohort were combined with the NIOSH job exposure matrix and work histories to estimate dose rates per unit of exposure score. We evaluated the effect of choices in regression model (regression on untransformed vs. ln-transformed data and inclusion of a nonzero regression intercept) as well as the impact of choices of elimination models and parameters on estimated AUCs for the cohort. Central estimates for dose rate parameters derived from the serum-sampled subcohort were applied with the elimination models to time-specific exposure scores for the entire cohort to generate AUC estimates for all cohort members. Use of the CADM resulted in improved model fits to the serum sampling data compared to the first-order models. Dose rates varied by a factor of 50 among different combinations of elimination model, parameter sets, and regression models. Use of a CADM results in increases of up to five-fold in AUC estimates for the more highly exposed members of the cohort compared to estimates obtained using the first-order model with 8.7-year half-life. This degree of variation in the AUC estimates for this cohort would affect substantially the cancer potency estimates derived from the mortality data from this cohort. Such variability and uncertainty in the reconstructed serum lipid AUC estimates for this cohort, depending on elimination model, parameter set, and regression model, have not been described previously and are critical components in evaluating the dose-response data from the occupationally exposed populations.     

The U.S. legalization program: a preliminary final report

The Immigration Reform and Control Act (IRCA) of 1986 made 4 types of aliens eligible to receive legalization benefits: 1) those who resided "continuously" in the US since January 1, 1982; 2) those who had worked in the US perishable-crop agriculture for 90 "man-days" in specified time periods (Special Agricultural Workers [SAWS]); 3) those who were in the US since before January 1, 1972; and 4) those classified as Cuban/Haitian entrants and who had been in the US since January 1, 1982. Estimates of the number of aliens eligible for legalization, not including SAWS, ranges from 1.834 million to 2.56 million. Estimates of undercounts of undocumented aliens are 10% for those who entered before 1975 and 37.5% for those who arrived after 1975. Other refinements in the estimates of undocumented aliens include adjustments for 1) ethnic group and location, 2) the growth of the undocumented population between the census date and the legalization eligibility date under IRCA, and 3) emigration and deportation rates. Out of the 1,581,800 applicants entered into the Immigration and Naturalization Service (INS) computers (from a total of 2.15 million applicants) as of May 20, 1988, 73.7% were Mexican nationals. Only 5 other countries contributed more than 1%: El Salvador (6.5%), Haiti (2.3%), Guatemala (2.2%), the Philippines (1%), and Colombia (1%). The Mexican percentage was unexpectedly high, perhaps because the legalization had been much more successful in the Southwest than anywhere else in the country. Reasons that Mexicans have a higher legalization participation rate than other nationalities include 1) the distant eligibility date; 2) ethnic differences among non-Mexican nationalities; 3) particularly in the northeast, fears of exposing one's illegal status to INS; 4) the difficulty of information reaching ethnic communities, 5) the reluctance of those already undergoing the naturalization process to risk the legalization process; and 6) the reluctance of employees to admit employment of undocumented aliens. In the end, more than 90% of applicants are expected to be granted temporary resident alien status (and about 70% of agricultural workers), for a total of more than 2 million people. Researchers estimate that 2.5 - 3 million more persons remain in an undocumented status in the US.     

The impact of international migration on fertility: an econometric population model

The authors develop an econometric model to examine the impact of migration on fertility in Greece in the period 1968-1986. In the model, the fertility equation is considered within a simultaneous equation system, and international migration is included as an explanatory factor of both fertility and per capita income. (SUMMARY IN FRE AND SPA)     

Research & clinical practice. Building a nursing research culture

The internalization of clinical nursing research values, norms, and attitudes via orientation and research development, along with the introduction of research tools (artifacts), constitutes the birthing phase of the acculturation process. The development of unit and individual research agendas and the implementation of research rounds illustrates a "bonding phase," in that nurses are bonding or weaving research into the fabric of their clinical practice. The final phase, stabilization, occurs when clinical nursing research is core to clinical nursing practice as illustrated by rewards or sanctions via performance evaluations, and provisions for release time for research participation.     

International law and human rights: trends concerning international migrants and refugees

Not with standing human rights linkages, migrants and refugees are often on the periphery of effective international protection. State sovereignty and self-regarding notions of community are used to deny or dilute substantive and procedural guarantees. Recently, even non- discrimination as a fundamental principle has been questioned, as has the system of refugee protection. This article located both migrants and refugees squarely within the human rights context, contrasting both inalienable rights with the demands of sovereignty, and juxtaposing the 2 in a context of existing and developing international standards. Migration and refugee flows will go on, and the developed world, in particular, must address the consequences - legal, humanitarian, socioeconomic, and cultural. Racism and institutional denials of basic rights daily challenge the common interest. This article shows how the law must evolve, responding coherently to contemporary problems, if the structure of rights and freedoms is to be maintained.     

The prevalence rates of pathological gambling: A look at methods

Planning the gambling environment requires protection of the public's health, safety and welfare. Whereas most public gaming provisions and statutes address the public's fears of organized crime as well as some welfare needs, rarely do they safeguard the public's health regarding the spread of the mental disease known as pathological gambling. Measurement of the prevalence and incidence of this disease would enable policy planners to evaluate both the state's responsibility for an epidemic and the adequacy of publicly funded treatment programs. The purpose of this paper is to examine the methods which underlie three different estimates of the prevalence rate of pathological gambling and to critique them in the light of sound epidemiological procedure. In 1975, the Institute for Social Research (ISR) of the University of Michigan conducted a national survey and a survey of the state of Nevada on behalf of the U.S. Commission on a National Policy Toward Gambling. Using discriminant function analysis coupled with subjective inspection of cases in the at-risk pool, the researchers estimated rates of probable and potential pathological gamblers. In 1984 and 1985, this author surveyed residents in the Delaware Valley and the state of Ohio using the cumulative clinical signs method which also posited rates of probable and potential pathological gamblers. In 1986, researchers at the Office of Mental Health for the State of New York employed a formal screening device to survey residents and proposed a rate of probable pathological gamblers and a rate of problem — although not pathological — gamblers. All three approaches produced different estimates. The utility of prevalence and incidence rate research in this field is threatened by a lack of consensus about the proper epidemiological procedure to be employed in arriving at these estimates. There is also confusion about the distinction between a probable and a potential pathological gambler. The planning purpose, method, validity and reliability of prevalence rate research about pathological gambling are addressed in this paper.     

The effects of the age and structure of population on family change]

The age structure of a population is one basic factor of population research. It is not only affected by birth, death, immigration, and marriage, but it also reflected in changes of family size. The article analyzed it from two aspects: (1) the age structure of population acts on the size and structure of the family. The younger the age structure, the larger the family size. Otherwise, it is the opposite. According to the 1982 census, 35.4% of the population was 0-14 years in rural areas, and average family size was 4.6; but in urban areas 26.0% of the population was 0-14 years and family size was 3.9. The family was characterized as a nuclear family as industrialization in economic development increased and the population aged. In the 1982 census, 64.7% were nuclear family and 6% were aging population in China. Three- generation families (or more) have decreased dramatically. The change of family size and structure is affected by change of internal family age structure. The younger population (0-14 years) is dependent and 90% live with their parents. The adult population (15-59) years are more affected by marriage, birth and social economic action. Families are established in this age period and give much more effect to fertility. The aging population (over 60) years is facing changes. They appear to be a "Defect" family because the wife or husband has passed away. They change from independent to dependent. 78.3% population over 60 years were dependent on children or social welfare, only 21.7% were independent according to the survey in Beijing Changping County.     

Big girls don't frown,big boys don't cry—Gender differences of professional actors in communicating emotion via facial expression

It was tested whether professional actors would be able to communicate emotional meaning via facial expression when this is presented to judges without context information. Forty takes were selected from movies, depicting a female or a male actor in close-up showing facial expression. These close-ups were selected by two expert judges, who knew the complete movie and had to agree on the emotion expressed or expected to be expressed by the female or male actor in the respective take. Five takes each were selected to represent the basic emotions of joy, sadness, fear, and anger. Twenty takes each were selected showing female and male actors. These 40 takes (edited in random order onto video tape) were presented to 90 judges (about half female and half male; about half younger pupils and about half older ones), whose task it was to judge the emotion(s) expressed on nine 5-point-emotion scales. Results indicated that female actors are somewhat better (though not statistically significant) in communicating emotion via facial expression without context than male actors are. Furthermore, significant interactions between portrayed emotion and gender of actors were found: While recognition rate for joy is very high and identical for both genders, female actors seem to be superior in communicating fear and sadness via facial expression, while male actors are more successful in communicating anger. A display rule approach seems to be appropriate for the interpretation of these results, indicating that gender-specific attempts to control/inhibit certain emotions do not only exist in real life, but also in movies.The research reported here was supported by a grant of the Deutsche Forschungsgemeinschaft (WA 519/2-2). I thank Uwe Balser and Tina Mertesacker for their help in selecting the stimuli, preparing the judgment tapes, recruiting subjects and conducting the study.     

Demographic behavior: controlled fertility

The current status of fertility and its control in France is reviewed. Consideration is given to changes in contraceptive usage, nuptiality, educational status and fertility, birth timing and spacing, and female labor force participation. The author notes that fertility has not declined significantly since the mid-1970s. Fertility differentials by geographical region and occupation are also considered.