2,111 research outputs found
Associated Primes of Spline Complexes
The spline complex whose top homology is
the algebra of mixed splines over the fan
was introduced by Schenck-Stillman in
[Schenck-Stillman 97] as a variant of a complex
of Billera [Billera 88]. In this paper we
analyze the associated primes of homology modules of this complex. In
particular, we show that all such primes are linear. We give two applications
to computations of dimensions. The first is a computation of the third
coefficient of the Hilbert polynomial of , including cases
where vanishing is imposed along arbitrary codimension one faces of the
boundary of , generalizing the computations in [Geramita-Schenck
98,McDonald-Schenck 09]. The second is a description of the fourth coefficient
of the Hilbert polynomial of for simplicial fans
. We use this to derive the result of Alfeld, Schumaker, and Whiteley
on the generic dimension of tetrahedral splines for
[Alfeld-Schumaker-Whiteley 93] and indicate via an example how this description
may be used to give the fourth coefficient in particular nongeneric
configurations.Comment: 40 pages, 10 figure
The L.A. Riot and the Economics of Urban Unrest
The Los Angeles riot of 1992 resulted in 52 deaths, 2,500 injuries and at least $446 million in property damage; this staggering toll rekindled interest in understanding the underlying causes of the widespread social phenomenon of rioting. We examine the causes of rioting using international data, evidence from the race riots of the 1960s in the U.S., and Census data on Los Angeles, 1990. We find some support for the notions that the opportunity costs of time and the potential costs of punishment influence the incidence and intensity of riots. Beyond these individual costs and benefits, community structure matters. In our results, ethnic diversity seems a significant determinant of rioting, while we find little evidence that poverty in the community matters.
Standard and Specialized Infant Formulas in Europe: Making, Marketing, and Health Outcomes
Infant formulas are the only suitable substitute for human milk. The most common infant formulas are standard formulas based on cow's milk. In addition, there are formulas for infants showing signs and symptoms of intolerance and for clinical conditions such as allergy, prematurity, and gastrointestinal diseases. A comprehensive review of the literature was made to review the composition of standard and specialized infant formulas and analyze indications for use, real or presumed nutrition differences and properties, and impact on infant growth. A brief consideration on costs is outlined for each formula. Over the past few years, industrial production and advertising of infant formulas have increased. Human milk still remains the most complete source of nutrition for infants and should be continued according to the current recommendations. Few differences exist between infant formulas, both for the nutrition action and the macronutrient/micronutrient composition. Specialized infant formulas have limited indications for use and high costs. The role of the pediatrician is crucial in the management of infant nutrition, promotion of breastfeeding, and prescribing of specialized formulas only in specific clinical conditions
The effects of oleylethanolamide on feeding behavior involve hypothalamic oxytocin neurons
In December 1992 Devane and his collaborators (Devane et al., 1992) reported
the isolation and structure elucidation of a porcine brain lipid component that selectively
displaced the binding of a high-affinity cannabinoid receptor ligand to
brain membrane preparations. This compound was the ethanolamide of arachidonic
acid (20:4, n-6) and was named anandamide (AEA) (Figure 1), after the
Sanskrit word for “bliss”, ananda. AEA was shown to be active in the tetrade of
mouse behavioral tests suggestive of cannabinoid-like activity, i.e. inhibition of
locomotor and rearing activity, hypothermy, catalepsy, and analgesia (Fride and
Mechoulam, 1993; Crawley et al., 1993). Another derivative of arachidonic acid
that activates cannabinoid receptors, 2-arachidonoylglycerol (2-AG), was discovered
in 1995 (Mechoulam et al., 1995; Sugiura et al., 1995). Although structurally
different from plant-derived cannabinoids, these compounds, in analogy with the
“endorphins” (i.e. the endogenous ligands of opiate receptors), were named “endocannabinoids”
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