802 research outputs found
Do Food Prices Affect Food Security? Evidence from the CPS 2002-2006
In this paper, we estimate the effect of food prices on food insecurity for SNAP recipients using data from the Current Population Survey and the recently published Quarterly Food At Home Price Database. We form a local food price index based on amounts of food for a household of four as established by the Thrifty Food Plan. We use an econometric model that accounts for the endogeneity of SNAP receipt to food insecurity and for household-level unobservables. We find that the average effect of food prices on the probability of food insecurity is positive and significant: an increase of one standard deviation in the price of our food basket is associated with an increase in food insecurity of between 1.3 and 2 percentage points for SNAP households. These results are fairly large in terms of the prevalence of food insecurity in our sample. An increase in food insecurity of this magnitude would be about 8 percent of total food insecurity prevalence for the populations in question. These results suggest that indexing SNAP benefits to local food prices could improve its ability to ameliorate the effects of food insecurity.food price, food insecurity, SNAP, discrete factor model, Demand and Price Analysis, Food Security and Poverty, I38,
Social Episodic-Like Memory in the Black-Capped Chickadee (Poecile Atricapillus)
Episodic memory is the ability to remember previously experienced past events (Tulving, 1992). An important component of episodic memory is autonoetic consciousness. Autonoetic consciousness is self-awareness that you personally experienced an event (Tulving, 1995). Historically, episodic memory was thought to be a purely human ability but recently episodic memory has been tested in animals by using what-where-when paradigms. Since autonoetic consciousness is not examined in animals, it is referred to as episodic-like memory.
The social component of episodic-like memory has not previously been examined in animals. The current study modified the what-where-when paradigm to test who and when components of episodic-like memory. In the first experiment, subordinate birds were required to associate a short retention interval (SRI) with the dominant bird being present and a long retention interval (LRI) with the dominant bird being absent. Dominant birds hinder the ability of a subordinate bird to access food. Episodic-like memory of who and when was demonstrated in SRI probe trials in which the dominant bird was absent. Subordinate birds behaved on SRI probe trials as if the dominant bird was present. In Experiment 2, the interval at which the dominant bird appeared was reversed. Subordinate birds behaved on LRI probe trials as if the dominant bird was present, when the dominant bird was actually absent. These results provide evidence for who and when components of episodic-like memory by requiring recollection of how long ago an individual last experienced a social encounter and using this to predict the absence or presence of a dominant bird
Cyclic Ovarian Hormone Modulation of Supraspinal Δ\u3csup\u3e9\u3c/sup\u3e-tetrahydrocannabinol-induced Antinociception and Cannabinoid Receptor Binding in the Female Rat
Estrous cycle-related fluctuations in delta-9-tetrahydrocannabinol (THC)-induced antinociception have been observed in the rat. The aim of this study was to determine which major ovarian hormone modulates the antinociceptive effects of i.c.v. THC, and whether hormone modulation of THC\u27s behavioral effects could be due to changes in brain cannabinoid receptors (CBr). Vehicle (oil) or hormones (estradiol or progesterone, or both) were administered to female rats on days 3 and 7 post-ovariectomy. On the morning or afternoon of day 8 or day 9, vehicle or THC (100 μg) was administered i.c.v. Paw pressure, tail withdrawal, locomotor activity and catalepsy tests were conducted over a 3-h period. Estradiol (with and without progesterone) enhanced THC-induced paw pressure antinociception only. Ovarian hormones time-dependently modulated CBr in brain structures that mediate antinociception and locomotor activity, but the changes observed in CBr did not parallel changes in behavior. However, the time course of CBr changes must be further elucidated to determine the functional relationship between receptor changes and antinociceptive sensitivity to THC
The Afterschool Leadership Landscape: Supporting and Strengthening Racial Equity
In 2019, the National AfterSchool Association (NAA) convened a series of leadership conversations focused on creating a culture of professionalization in afterschool, which included a discussion of the need to build a leadership pipeline and to foster more diverse leadership, starting with a focus on supporting and retaining leaders from minoritized racial and ethnic backgrounds. These leader-focused discussions were a natural next step in NAA's long track record of commitment to equity and advocacy for the professionalization of the afterschool field, including through the development of Core Knowledge and Competencies for Afterschool and Youth Development Professionals, and by annually honoring the Next Generation of Afterschool Leaders. NAA is now elevating the importance of building a diverse leadership pipeline through the launch of a Professional Learning Community (PLC) in spring 2020, with grant support from the S.D. Bechtel, Jr. Foundation and in partnership with the California School-Age Consortium (CalSAC) and Development Without Limits (DWL). NAA also engaged Policy Studies Associates (PSA) and Public Profit as learning and research partners. This brief, researched and authored by PSA and leveraging interview and survey data from Public Profit, results from a collaborative effort intended to frame efforts to embrace, support, and retain afterschool leaders of color.
Evaluation of the Stormwater Capture Potential of New York City Soils: Implications of Infiltration Rate Variability on Urban Runoff Predictions
The properties used to characterize soils and, more specifically, those that are used to describe the rate at which water infiltrates into them, are key parameters in most rainfall-runoff models. Because these parameters are known to be highly variable, they are a known source of uncertainty in our ability to predict runoff from pervious surfaces. The goals of this study were to a) characterize the heterogeneity in soil and infiltration characteristics in specific types of pervious surfaces found in New York City, and b) to study the potential effect of this heterogeneity on prediction of the total volume and peak rate of runoff from specific rainfall hyetographs. Characterization of soil and infiltration characteristics was performed at a variety of sites throughout NYC during Summer and Fall 2009. As expected, statistical analysis of the data, which includes nearly two dozen individual tests, showed high variability. The USEPA Stormwater Management Model, (SWMM) an industry standard, was then used to examine the impact of this heterogeneity on predictions of peak flow and total runoff volume for a design storm. The preliminary results of this work suggest that although soil and infiltration properties are highly variable, only a small portion of this range can significantly alter the runoff predictions obtained from SWMM using this particular design storm. Future research will address the significance of the variability in runoff predictions given a more diverse set of storm events for more generalizeable results
Saturation mutagenesis reveals manifold determinants of exon definition.
To illuminate the extent and roles of exonic sequences in the splicing of human RNA transcripts, we conducted saturation mutagenesis of a 51-nt internal exon in a three-exon minigene. All possible single and tandem dinucleotide substitutions were surveyed. Using high-throughput genetics, 5560 minigene molecules were assayed for splicing in human HEK293 cells. Up to 70% of mutations produced substantial (greater than twofold) phenotypes of either increased or decreased splicing. Of all predicted secondary structural elements, only a single 15-nt stem-loop showed a strong correlation with splicing, acting negatively. The in vitro formation of exon-protein complexes between the mutant molecules and proteins associated with spliceosome formation (U2AF35, U2AF65, U1A, and U1-70K) correlated with splicing efficiencies, suggesting exon definition as the step affected by most mutations. The measured relative binding affinities of dozens of human RNA binding protein domains as reported in the CISBP-RNA database were found to correlate either positively or negatively with splicing efficiency, more than could fit on the 51-nt test exon simultaneously. The large number of these functional protein binding correlations point to a dynamic and heterogeneous population of pre-mRNA molecules, each responding to a particular collection of binding proteins
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Increasing Student Employability through University/Industry Collaboration: A study in South Africa, the UK and Finland
Due to its high youth unemployment the study focused on South Africa but covered selected universities in the UK and Finland for the purposes of comparison and benchmarking. The purpose of the study was to determine the perceptions of industry, lecturers and students on the competencies gained at university and the benefits of university enterprise collaboration (UEC) to students. Data was collected through mixed methods: a structured survey and semi-structured interviews. UEC is shown to increase student employability and work-readiness but several challenges to implementing such collaboration exist, particularly in South Africa. Based on the results the paper proposes that technology can be used to overcome the gaps in achieving effective UEC and thereby increasing the employability of students in South Africa
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