757 research outputs found
Better Targeting, Better Outcomes
A multitude of design decisions influence the performance of voluntary conservation programs. This Economic Brief is one of a set of five exploring the implications of decisions policymakers and program managers must make about who is eligible to receive payments, how much can be received, for what action, and the means by which applicants are selected. The particular issue addressed here is options for targeting program payments to where they can yield the greatest gain.Agricultural and Food Policy, Environmental Economics and Policy,
VALUING MARGINAL CHANGES IN THE QUALITY OF AN ENVIRONMENTAL ASSET
We present a model that extends the replacement cost theory to cases where benefits are restored for multiple years. Our theoretical framework derives a functional relationship between investments expenditures and environmental benefits. By extending the investment framework, we model reservoir benefits as a function of marginal changes in soil erosion.Environmental Economics and Policy,
INCREASED RESERVOIR BENEFITS: THE CONTRIBUTION OF SOIL CONSERVATION PROGRAMS
The objective of this research is to value soil conservation's impact on reservoirs. Using a model based on replacement cost, we estimate the benefits gained by marginal decreases in soil erosion for more than 75,000 reservoirs across the contiguous States. We aggregate benefits across the reservoirs within each of the 2,111 U.S watersheds in order to produce regional benefit estimates. Results show that a one-ton reduction in soil erosion provides benefits ranging from zero to 139 million in reservoir benefits.Environmental Economics and Policy,
Economic Valuation of Environmental Benefits and the Targeting of Conservation Programs: The Case of the CRP
The range of environmental problems confronting agriculture has expanded in recent years. As the largest program designed to mitigate the negative environmental effects of agriculture, the Conservation Reserve Program (CRP) has broadened its initial focus on reductions in soil erosion to consider other landscape factors that may also be beneficial. For example, preserving habitats can help protect wildlife, thus leading to more nature-viewing opportunities. This report demonstrates how nonmarket valuation models can be used in targeting conservation programs such as the CRP.Environmental Economics and Policy,
Suspect Linkage: The Interplay of State Taxing and Spending Measures in the Application of Constitutional Antidiscrimination Rules
This article examines an important and recurring question that courts frequently resolve, but rarely analyze: whether taxing and spending measures should be viewed together when a state imposes a nondiscriminatory tax but also affords relief to some taxpayers through government spending. The answer to this question will often determine whether the state\u27s actions violate constitutional strictures against discriminatory taxation. The taxing measure and the spending measure will generally pass muster if viewed in isolation. After all, courts rarely invalidate nondiscriminatory taxing measures on constitutional grounds. And true government spending measures, if considered alone, plainly fall outside the reach of constitutional restraints against discriminatory government taxation. If the two measures are considered together, the entire scheme will violate the operative antidiscrimination rule, because payments made to the favored group will produce the prohibited disparity in effective tax burdens. If, on the other hand, the court considers the two measures separately, they will emerge unscathed from the constitutional attack
Commerce Clause Restraints on State Business Development Incentives
In this Article, we explore the ill-defined distinction between the constitutional carrot and the unconstitutional stick in state tax, subsidy, and related cases. Part I examines the restraints that the Commerce Clause imposes on state tax incentives. It canvasses the general principles limiting discriminatory state taxation, explores the Court\u27s decisions addressing state tax incentives, and proposes a framework of analysis for adjudicating the validity of such incentives. Part I concludes by considering the constitutionality of a variety of state tax incentives within our suggested framework and also under alternative approaches that courts might utilize. Part II examines the restraints that the Commerce Clause imposes on state subsidies. It begin with a consideration of the Court\u27s seminal case in this field, West Lynn Creamery, Inc. v. Healy. After demonstrating that West Lynn Creamery does not jeopardize ordinary business subsidies, Part II considers the constitutionality of subsidies along two dimensions. First, it looks at subsidies in terms of their intended beneficiaries, focusing on whether it matters for Commerce Clause purposes that the subsidy targets a particular firm rather than a general class of businesses. Second, it evaluates whether the particular form the subsidy takes--for example, a cash grant, a property transfer, or a user fee waiver--alters the constitutional calculus in applying the dormant commerce clause. Part II concludes that neither the target nor the form of the subsidy ordinarily makes a difference. Rather, discriminatory subsidies, unlike discriminatory tax breaks, are almost always constitutional. In Part III, we consider the theoretical underpinnings of the strong tax-break/subsidy distinction that permeates this field. We suggest that this distinction resonates with the law\u27s deep regard for considerations of form. We observer, in particular, that the distinction may grow out of the same cautionary function that helps explain many rules that require use of specified formal structures to achieve legally enforceable results in the private-law context
Proof of a conjecture of Polya on the zeros of successive derivatives of real entire functions
We prove Polya's conjecture of 1943: For a real entire function of order
greater than 2, with finitely many non-real zeros, the number of non-real zeros
of the n-th derivative tends to infinity with n. We use the saddle point method
and potential theory, combined with the theory of analytic functions with
positive imaginary part in the upper half-plane.Comment: 26 page
LEARNING ARITHMETIC READ-ONCE FORMULAS*
Abstract. A formula is read-once if each variable appears at most once in it. An arithmetic read-once formula is one in which the operators are addition, subtraction, multiplication, and division. We present polynomial time algorithms for exact learning of arithmetic read-once formulas over a field. We present a membership and equivalence query algorithm that identifies arithmetic read-once formulas over an arbitrary field. We present a randomized membership query algorithm (i.e., a randomized black box interpolation algorithm) that identifies such formulas over finite fields with at least 2n + 5 elements (where n is the number of variables) and over infinite fields. We also show the existence of nonuniform deterministic membership query algorithms for arbitrary read-once formulas over fields of characteristic 0, and division-free read-once formulas over fields that have at least 2n + elements. For our algorithms, we assume we are able to perform efficiently arithmetic operations on field elements and compute square roots in the field. It is shown that the ability to compute square roots is necessary in the sense that the problem of computing n square roots in a field can be reduced to the problem of identifying an arithmetic formula over n variables in that field. Our equivalence queries are of a slightly nonstandard form, in which counterexamples are required not to be inputs on which the formula evaluates to 0/0. This assumption is shown to be necessary for fields of size o(n! log n) in the sense that we prove there exists no polynomial time identification algorithm that uses only membership and standard equivalence queries
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An ANGPTL4-ceramide-protein kinase Cζ axis mediates chronic glucocorticoid exposure-induced hepatic steatosis and hypertriglyceridemia in mice.
Chronic or excess glucocorticoid exposure causes lipid disorders such as hypertriglyceridemia and hepatic steatosis. Angptl4 (angiopoietin-like 4), a primary target gene of the glucocorticoid receptor in hepatocytes and adipocytes, is required for hypertriglyceridemia and hepatic steatosis induced by the synthetic glucocorticoid dexamethasone. Angptl4 has also been shown to be required for dexamethasone-induced hepatic ceramide production. Here, we further examined the role of ceramide-mediated signaling in hepatic dyslipidemia caused by chronic glucocorticoid exposure. Using a stable isotope-labeling technique, we found that dexamethasone treatment induced the rate of hepatic de novo lipogenesis and triglyceride synthesis. These dexamethasone responses were compromised in Angptl4-null mice (Angptl4-/-). Treating mice with myriocin, an inhibitor of the rate-controlling enzyme of de novo ceramide synthesis, serine palmitoyltransferase long-chain base subunit 1 (SPTLC1)/SPTLC2, decreased dexamethasone-induced plasma and liver triglyceride levels in WT but not Angptl4-/- mice. We noted similar results in mice infected with adeno-associated virus-expressing small hairpin RNAs targeting Sptlc2. Protein phosphatase 2 phosphatase activator (PP2A) and protein kinase Cζ (PKCζ) are two known downstream effectors of ceramides. We found here that mice treated with an inhibitor of PKCζ, 2-acetyl-1,3-cyclopentanedione (ACPD), had lower levels of dexamethasone-induced triglyceride accumulation in plasma and liver. However, small hairpin RNA-mediated targeting of the catalytic PP2A subunit (Ppp2ca) had no effect on dexamethasone responses on plasma and liver triglyceride levels. Overall, our results indicate that chronic dexamethasone treatment induces an ANGPTL4-ceramide-PKCζ axis that activates hepatic de novo lipogenesis and triglyceride synthesis, resulting in lipid disorders
The Conservation Reserve Program: Economic Implications for Rural America
This report estimates the impact that high levels of enrollment in the Conservation Reserve Program (CRP) have had on economic trends in rural counties since the program's inception in 1985 until today. The results of a growth model and quasi-experimental control group analysis indicate no discernible impact by the CRP on aggregate county population trends. Aggregate employment growth may have slowed in some high-CRP counties, but only temporarily. High levels of CRP enrollment appear to have affected farm-related businesses over the long run, but growth in the number of other nonfarm businesses moderated CRP's impact on total employment. If CRP contracts had ended in 2001, simulation models suggest that roughly 51 percent of CRP land would have returned to crop production, and that spending on outdoor recreation would decrease by as much as $300 million per year in rural areas. The resulting impacts on employment and income vary widely among regions having similar CRP enrollments, depending upon local economic conditions.Community/Rural/Urban Development, Land Economics/Use,
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