600 research outputs found
Cigarette Taxes and the Social Market
Previous researchers have argued that the social market for cigarettes insulates its participants from policies designed to curb youth smoking. Using state Youth Risk Behavior Survey data, we examine whether recent changes in state cigarette taxes affected how young smokers obtained their cigarettes. Our estimates suggest that tax increases reduce youth smoking participation primarily through their effect on third-party purchase, although there is evidence that they are negatively related to borrowing among younger teenagers and negatively related to direct purchase among older teenagers.youth smoking, cigarette taxes
High on Life? Medical Marijuana Laws and Suicide
Using state-level data for the period 1990 through 2007, we estimate the effect of legalizing medical marijuana on suicide rates. Our results suggest that the passage of a medical marijuana law is associated with an almost 5 percent reduction in the total suicide rate, an 11 percent reduction in the suicide rate of 20- through 29-year-old males, and a 9 percent reduction in the suicide rate of 30- through 39-year-old males. Estimates of the relationship between legalization and female suicides are less precise and are sensitive to functional form.medical marijuana laws, marijuana, alcohol, suicide
Observations and Theoretical Implications of GRB 970228
GRB 970228 is the first gamma ray burst for which prolonged post-burst
transient x-ray, optical, and infrared emission has been detected. Recent
Hubble Space Telescope observations show that the transient consists of two
components: a point source, which is known to be fading, and an extended
source, which is possibly fading. I fit standard fireball remnant models to the
first month of x-ray, optical, and infrared measurements, which may be done
without assuming a GRB distance scale. I show that its emission is consistent
with that of the remnant of a relativistically expanding impulsive fireball in
which a forward shock dominates the emission of the GRB event: the piston
model. However, two discrepant measurements may indicate that the post-burst
flux varies by factors of approximately 3 on timescales of days or weeks.
Furthermore, using the HST observations and the fitted model, I show that the
extended object probably is fading, which may place GRB 970228 at galactic halo
distances.Comment: Accepted to the Astrophysical Journal Letters, 11 pages, LaTe
How Would Universities Respond to Increased Federal Support for Graduate Students?
[Excerpt] This paper has demonstrated that doctorate-producing universities respond to changes in the number of FTSEG students supported on external funds by altering the number of FTSEG students that they support on institutional funds. While institutional adjustment to changes in external support levels appears to be quite rapid, in the aggregate the magnitude of these responses is quite small. A increase of 100 in the number of FTSEG students supported by external funds is estimated to reduce the number supported on institutional funds by 22 to 23. Since some of the institutional funds that are saved may be redirected to support graduate students in the humanities and other fields not represented in the data, the total effect of such a policy change on institutional support for graduate students is probably somewhat smaller
Natural and Synthetic GHSR1a Agonists as Neuroprotective Agents in Models of Parkinson's disease
Parkinson’s disease (PD) is the second most prevalent neurodegenerative disorder in humans. It is characterised by the progressive loss of the A9 (Girk2+) subpopulation of dopamine (DA) neurones in the Substantia Nigra Pars Compacta (SNpc) resulting in resting tremor, bradykinesia and rigidity. The majority of PD cases are idiopathic. However, environmental toxins that inhibit the mitochondrial electron transport chain cause PD-like symptoms and recent studies of rare familial PD implicate metabolic dysfunction as a possible cause of DA nerve cell loss. We propose that the homeostatic hormone, acyl-ghrelin, may prevent DA neurone loss by preserving nerve cell metabolism during bioenergetics stress. In the in-vivo MPTP-toxin model of PD acyl-ghrelin prevents SNpc DA neurone loss in an acyl-ghrelin receptor (GHSR)-dependent manner (Andrews et al.2009). Here, using the eGFP-GHSR reporter mouse we demonstrate co-localised expression of the GHSR with TH+ and Girk2+ SNpc neurones. This suggests that acyl-ghrelin may exert a direct protective effect on A9 DA neurones via GHSR+ signalling. We show that acyl-ghrelin attenuated the 6-OHDA-induced SN lesion in unilateral lesioned rats. Moreover, this neuroprotection is consistent with the preservation of motor function. Using a mouse-midbrain-derived neuronal cell line (SN4741), immune-positive for TH+/ Girk2+/GHSR+, we assess the neuroprotective potential of acyl-ghrelin and GHSR1a agonist, JMV2894, in an in-vitro rotenone-based PD model. Furthermore, we show acyl-ghrelin as a modulator of intra-cellular AMPK and ACC phosphorylation and investigate the protective effects on mitochondrial health and morphology using automated images analysis and TEM. Acyl-ghrelin activated cellular pathways associated with protecting against energetic stress and promoting healthy aging. These data suggest that Acyl-Ghrelin may be a potential new therapeutic target for PD
What Do You Think Would Make You Happier? What Do You Think You Would Choose?
Would people choose what they think would maximize their subjective well-being (SWB)? We present survey respondents with hypothetical scenarios and elicit both choice and predicted SWB rankings of two alternatives. While choice and predicted SWB rankings usually coincide in our data, we find systematic reversals. We identify factors—such as predicted sense of purpose, control over one\u27s life, family happiness, and social status—that help explain hypothetical choice controlling for predicted SWB. We explore how our findings vary by SWB measure and by scenario. Our results have implications regarding the use of SWB survey questions as a proxy for utility
Genome-wide SNP identification by high-throughput sequencing and selective mapping allows sequence assembly positioning using a framework genetic linkage map
Determining the position and order of contigs and scaffolds from a genome assembly within an organism’s genome remains a technical challenge in a majority of sequencing projects. In order to exploit contemporary technologies for DNA sequencing. We developed a strategy for whole genome single nucleotide polymorphism sequencing allowing the positioning of sequence contigs onto a linkage map using the bin mapping method. The strategy was tested on a draft genome of the fungal pathogen Venturia inaequalis, the causal agent of apple scab, and further validated using sequence contigs derived from the diploid plant genome Fragaria vesca. Using our novel method we were able to anchor 70% and 92% of sequences assemblies for V. inaequalis and F. vesca, respectively, to genetic linkage maps. We demonstrated the utility of this approach by accurately determining the bin map positions of the majority of the large sequence contigs from each genome sequence and validated our method by mapping single sequence repeat markers derived from sequence contigs on a full mapping population.Deciduous Fruit Producers Trust
THRIP Program
National Research Foundation
Claude Harris Leon FoundationWeb of Scienc
Invariant Peano curves of expanding Thurston maps
We consider Thurston maps, i.e., branched covering maps
that are postcritically finite. In addition, we assume that is expanding in
a suitable sense. It is shown that each sufficiently high iterate of
is semi-conjugate to , where is equal to the
degree of . More precisely, for such an we construct a Peano curve
(onto), such that
(for all ).Comment: 63 pages, 12 figure
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