5,117 research outputs found
An end to the neglect of the problems of the Negro woman!
https://stars.library.ucf.edu/prism/1466/thumbnail.jp
The economic effects of disability on intrafamilial time allocation: labor supply, self-employment, household production and leisure
The economic effects of disability are measured by econometric analysis of the own- and cross-wage effects of reduced marginal productivity when the head of the household is disabled. The trade-offs in intrafamilial time allocation include not only the work/leisure decision, but allow for time to be allocated to self-employment and household production. A measure of the marginal productivity of time is not observable in all activities. However, the general model presented is fitted to data for all individuals--wage earners and others, disabled and able-bodied--to provide empirical estimates of the shadow price of time in all uses. The analyses take into account sample selection bias. Additionally, income and social security taxes are allowed for in the model;The objectives of this study are: (1) to develop a general model of intrafamilial time allocation when the head of the household is disabled, and (2) to fit an empirical specification of the model to a micro data set obtained from the Panel Study of Income Dynamics. The data set was generated by the University of Michigan, with the sample drawn from the national population. The analyses use cross-sectional data from 1971;In general, the own-wage effects for the non-Black head of the household indicate that a decrease in the wage rate reduces the number of hours he allocates to the labor market and increases hours of self-employment, household production and leisure. Cross-wage effects of a decline in the head\u27s wage rate show that the spouse increases work for money and reduces hours in household production and leisure. When the non-Black head of the household experiences reduced marginal productivity due to disability, the spouse substitutes her time in the market for his and he substitutes his time in household production for her home time. For the Black households, the head\u27s own-wage effect indicates that a decline in the wage rate reduces hours of work for money and increases home time and leisure. The cross-wage effect of his reduced marginal productivity reduces hours of work for money and leisure of the spouse and increases her time in household production. For the Black household, reduced marginal productivity of the head results in a reallocation of time by both head and spouse from work for money to household production
Empowering Decision Makers to Avoid the Oversizing of Building Service Systems
Oversizing of building service systems has a direct impact on building efficiency and operational costs. The research of this paper highlights several major contributors to the issue of oversizing. A key factor is the excessive and uncoordinated application of design margins applied during the multiple stages of a building services project; others include, a lack of communication and transparency across the various stakeholder groups, and the use of vague or unreliable data upon which initial project requirements are based. The impact of these factors on system performance and cost, and how these can impede on a building's ability to meet energy efficiency targets are analysed and discussed.
The paper emphasizes the need to develop robust processes that capture the scope and rationale for the margins applied, and to communicate this knowledge in a clear and unambiguous format, to all project stakeholders. The development of flexible and alternative design solutions that apply diversity principles, such as different backup systems to provide resilience rather than the traditional ‘like-for-like’ redundancy solutions, are also explored
Evidence of extra-mixing in field giants as traced by lithium and carbon isotope ratio
Although not predicted by standard stellar evolution, it is known that the
surface abundance of light elements changes during the red giant branch (RGB)
as a result of extra-mixing. This is associated usually with thermohaline
mixing acting after the RGB bump. Peculiar lithium-enriched RGB stars might
also be related to either enhanced extra-mixing or pollution from external
sources. We measure the lithium (Li) abundance and carbon isotopic ratio
C12/C13 in a sample of 166 field red giants with -0.3<[Fe/H]<0.2, targeted by
the EXPRESS radial velocity program to analyze the effects of extra-mixing. The
Li abundance pattern is complicated to interpret, but the comparison between
RGB and core-He burning giants shows the effects of extra-mixing consistent
with thermohaline. The most Li-enriched giant in the sample was classified as a
RGB star close to the luminosity function bump with low C12/C13. Given that the
C12/C13 should not be affected by external mechanisms, contamination by an
external source, such as a planet, does not seem to be the source of the high
Li. The C12C13 presents new clues to describe the extra-mixing. There is a
decreasing correlation between mass and C12/C13 in the RGB and an increasing
correlation in the horizontal branch, which, once again, is consistent with
thermohaline mixing. Our data also shows a correlation between C12/C13 and
[Fe/H]. There is no evident impact of binarity either on Li or C12/C13. Our
sample shows behavior that is consistent with additional mixing acting after
the RGB bump. Li, which is heavily affected by rotational mixing and other
processes, does not show a clear trend. Instead, the C12/C13 could be the best
tool to study mixing in red giants. Additional measurements of C12/C13 in field
stars would greatly improve our ability to compare with models and understand
the mixing mechanisms.Comment: 15 pages, 12 figures, submitted to A&A, comments welcom
Synthesis and biological evaluation of anti-Toxoplasma gondii activity of a novel scaffold of thiazolidinone derivatives
We designed and synthesised novel N-substituted 1,3-thiazolidin-4-one derivatives for the evaluation of their anti-Toxoplasma gondii efficacy. This scaffold was functionalised both at the N1-hydrazine portion with three structurally different moieties and at the lactam nitrogen with substituted benzyl groups selected on the basis of our previous structure-activity relationships studies. Using three different assay methods, the compounds were assessed in vitro to determine both the levels of efficacy against the tachyzoites of T. gondii (IC50 = 5-148 μM), as well as any evidence of cytotoxicity towards human host cells (TD50 = 68 to ≥320 μM). Results revealed that ferrocene-based thiazolidinones can possess potent anti-tachyzoite activity (TI =2-64)
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