Welfare Benefits and Female Headship in U.S. Time Series

A considerable amount of work has been done on the relationship between AFDC benefits and family structure in the United States. The evidence to date—based on cross-state variation in welfare benefits and family structure, often with state fixed effects—indicates that there is some nonzero effect of those benefits on marriage and fertility, although disagreement remains about the magnitude of the effect. It is undisputed, however, that time-series trends in family structure are not correlated in the direction that the cross-state evidence would suggest, because real benefits have been falling, even relative to wages, in aggregate time series. This paper reexamines the time-series evidence with particular attention to the role of wages in explaining trends in headship, and notes that the correct specification includes male as well as female wages. When both are controlled, welfare benefits have a slight positive impact on female headship even in time series. The results demonstrate the importance of labor market factors in explaining trends in female headship.

Combined pyrolysis and radiochemical gas chromatography for studying the thermal degradation of polymers

Pyrolysis gas chromatography and radioactive tracer techniques have been used independently to study the thermal degradation of polymers. In these laboratories the two techniques have been combined to elucidate some of the mechanisms of the thermal degradation of epoxy resins and polyimides. This paper describes the apparatus developed for this work

The Effect of Welfare on Marriage and Fertility: What Do We Know and What Do We Need to Know?

The recent literature on the effects of welfare on marriage and fertility includes studies employing a wide variety of methodologies and data sets and covering different time periods. A majority of the studies show that welfare has a significantly negative effect on marriage or positive effect on fertility rather than none at all, and thus the current consensus is that the welfare system probably has some effect on these demographic outcomes. Considerable uncertainty surrounds this consensus because a sizable minority of the studies find no effect at all, because the magnitudes of the estimated effects vary widely, and because puzzling and unexplained differences exist across the studies by race and methodological approach. At present, and with the information provided in the studies, the source of these disparities cannot be determined. While a neutral weighing of the evidence still leads to the conclusion that the welfare system affects marriage and fertility, research needs to be conducted to resolve the conflicting findings.

The effect of work and training programs on entry and exit from the welfare caseload

To policymakers, the major attraction of work and training programs for welfare recipients is that they hold out the prospect that recipients can be moved off the rolls and into self-sufficiency in the private labor market, thereby decreasing welfare costs and caseloads. This paper considers the possibility that such programs may also affect the attractiveness of welfare in the first place, either by making welfare less desirable because the work- training program is viewed as a burden, or by making it more desirable because the program is viewed favorably by potential applicants. Such responses are termed "entry-rate effects." Some empirical estimates of these effects are presented which suggest that entry-rate responses, whether positive or negative, may affect the caseload more than the direct effect of the programs in moving recipients off the rolls.

Codling moth (Lepid.: Tortricidae): Disruption of sexual communication with an antipheromone [(E,E)-8,1O-dodecadien-1-O1 acetate]

When broadcast applications of [E, E]-8,10-dodecadien-1l-ol acetate an antipheromone of the codling moth, <i>Cydia pomonella</i> (L.), were made to apple or pear orchards, the catch of male codling moths was reduced in traps baited with either synthetic sex pheromone or virgin females. When the antipheromone, at a rate of 11.25g AI/0.4 ha was applied broadcast to pear trees using a ground dispenser, male response to pheromone- or female-baited traps was completely inhibited for 9 days with no significant reduction thereafter. Based on these and earlier results, it is concluded that (E,E)-8,10-dodecadien-1l-o1 acetate inhibits male codling moth response, whether the sources are placed in close proximity to the attractive agent or distributed in a broadcast application. These results contradict previous arguments that antipheromones as a group may not be effective in the field when used to permeate large volumes of air

Dream Self-Reflectiveness as a Learned Cognitive Skill

Many prominent researchers subscribe to the notion that dreaming is cognitively deficient relative to normal waking consciousness (Foulkes,1983; Hartmann, 1973; Koukkou & Lehman, 1983). Dreams are perceived as massively non-reflective and single-minded as evidenced by their apparent lack of imagination, lack of lucidity (awareness of dreaming while dreaming), and tendency to be forgotten (Rechtschaffen, 1978). The notion of dream ‘isolation’ from other systems of consciousness has been posited by Rechtachaffen as an inescapable conclusion once these characteristics of dreaming have been understood

Myocardial Infarction After General Anesthesia

Few statistics are available about the incidence of primary or recurrent myocardial infarction after anesthesia. Mortality rates and their relation to age and sex, and to type and duration of anesthesia in existing reports, are based on a relatively small number of cases. This review attempts to provide additional data on these questions by analyzing a 2-year experience in a large anesthetic practice

An economic survey of New Zealand wheatgrowers : survey no. 2

This is survey number 2. No. 1 was know as "National wheatgrowers' survey"This Report is the second in an annual series of economic surveys of New Zealand wheatgrowing farms. These surveys have been undertaken by the Agricultural Economics Research Unit at Lincoln College on behalf of Wheat Growers Sub-Section of Federated Farmers of New Zealand Inc. Specific attention has been focused on the physical characteristics of wheatgrowing farms, the area of wheat and other crops sown, wheat yields, cultural practices and costs and returns for the 1977/78 wheat crop. An attempt has also been made to allocate plant and machinery overhead costs to the wheat enterprise on both an historical and current cost basis. The need for current and detailed information from the Survey involved two visits to the farms in the sample; one in the spring following drilling and the second in the autumn after harvest

Molecules in clusters: the case of planar LiBeBCNOF built from a triangular form LiOB and a linear four-center species FBeCN

Krueger some years ago proposed a cluster LiBeBCNOF, now called periodane. His ground-state isomer proposal has recently been refined by Bera et al. using DFT. Here, we take the approach of molecules in such a cluster as starting point. We first study therefore the triangular molecule LiOB by coupled cluster theory (CCSD) and thereby specify accurately its equilibrium geometry in free space. The second fragment we consider is FBeCN, but treated now by restricted Hartree-Fock (RHF) theory. This four-center species is found to be linear, and the bond lengths are obtained from both RHF and CCSD calculations. Finally, we bring these two entities together and find that while LiOB remains largely intact, FBeCN becomes bent by the interaction with LiOB. Hartree-Fock and CCSD theories then predict precisely the same lowest isomer found by Bera et al. solely on the basis of DFT.Comment: to appear in Phys. Lett.