1,289 research outputs found
The incorporation of solar photovoltaics into a model of residential energy demand
Solar photovoltaics (PV) provides electricity users with an array of alternatives to grid-connected electricity- the alternatives are more capital intensive and less grid-electricity intensive than traditional electricity sources. The added capital intensity is generated by combinations of photovoltaic solar cells and storage devices. Of course, once the PV installations are in place, less grid-connected electricity will be required to provide a given level of electrical output [4]. The Department of Energy is currently conducting analyses to assess the commercial potential for PV in various user sectors. The residential sector is one that is receiving close scrutiny. In order to analyze and estimate the commercial potential for PV, the demand for electricity and electrical residential appliances must be measured. This can be accomplished realistically only within an interfuel substitution model of residential energy deman
A generalized logit formulation of individual choice
Probability models of individual choice consist of two
components: a formulation of random utility and the stochastic
specification of that utility. Usually separable direct random
utility is assumed. With Weibull error terms, logit analysis
results. However, logit analysis suffers from the "assumed"
"independence of irrelevant alternatives". It is the contention
of this paper that these difficulties result from the usual
restrictive utility formulation. A more general indirect
random utility formulation is introduced. Estimates of the
resulting generalized logit and the more restrictive logit models
are presented. Hypothesis testing is reported which rejects the
restrictive utility formulations which dominate the literature.Prepared under Dept. of Energy contract no. EX-76-A-01-2295, Task order no.37
Why paper mills clean up : determinants of pollution abatement in four Asian countries
The authors find strong evidence that despite weak or nonexistent formal regulation and enforcement of environmental standards, many plants in South and Southeast Asia are clean. At the same time, many plants are among the world's worst polluters. To account for the extreme variation among plants, the authors review evidence from a survey of pollution abatement by 26 pulp and paper plants in four countries: Bangladesh, India, Indonesia, and Thailand. They incorporate 3 sets of factors affecting pollution intensity: plant characteristics, economic considerations, and external pressure from the government and private stakeholders. They find that the level of pollution abatement is positively associated with scale and competitiveness, negatively associated with public ownership, and unaffected by foreign links (in ownership or financing). Informal regulation, or community pressure on plants works to abate pollution, with high income being a powerful predictor of effectiveness. Privatization, to the extent that it increases plant efficiency, can significantly improve environmental performance. To prevent environmental injustice in poor or marginalized communities, the authors conclude, governments may want to consider strategies for improving their participation, and may want to target regulation to address pollution problems among them.Environmental Economics&Policies,Water and Industry,Water Conservation,Pollution Management&Control,Sanitation and Sewerage,Environmental Economics&Policies,Water and Industry,Pollution Management&Control,Sanitation and Sewerage,TF030632-DANISH CTF - FY05 (DAC PART COUNTRIES GNP PER CAPITA BELOW USD 2,500/AL
Perspective: tobacco manufacturers are now compensating states for smoking-related costs: how will this affect the economy?
Smoking out the social and economic benefits of the 1998 tobacco settlement for Massachusetts.Tobacco industry ; Medical care, Cost of
The Economic Impacts of the Tobacco Settlement
Recent litigation against major tobacco companies culminated in a Master Settlement Agreement' (MSA) under which the participating companies agreed to compensate most states for Medicaid expenses. We outline the terms of the settlement and analyze whether it was a move toward economic efficiency using data from Massachusetts. Medicaid spending will fall, but only a modest amount ($0.1 billion). The efficiency issue turns mainly on the treatment of health benefits from reduced smoking induced by the settlement. We conclude that the settlement was a move towards economic efficiency.
Migration then assembly: Formation of Neptune mass planets inside 1 AU
We demonstrate that the observed distribution of `Hot Neptune'/`Super-Earth'
systems is well reproduced by a model in which planet assembly occurs in situ,
with no significant migration post-assembly. This is achieved only if the
amount of mass in rocky material is -- interior to 1
AU. Such a reservoir of material implies that significant radial migration of
solid material takes place, and that it occur before the stage of final planet
assembly.
The model not only reproduces the general distribution of mass versus period,
but also the detailed statistics of multiple planet systems in the sample.
We furthermore demonstrate that cores of this size are also likely to meet
the criterion to gravitationally capture gas from the nebula, although
accretion is rapidly limited by the opening of gaps in the gas disk. If the
mass growth is limited by this tidal truncation, then the scenario sketched
here naturally produces Neptune-mass objects with substantial components of
both rock and gas, as is observed.
The quantitative expectations of this scenario are that most planets in the
`Hot Neptune/Super-Earth' class inhabit multiple-planet systems, with
characteristic orbital spacings. The model also provides a natural division
into gas-rich (Hot Neptune) and gas-poor (Super-Earth) classes at fixed period.
The dividing mass ranges from at 10 day orbital periods to
at 100 day orbital periods. For orbital periods
days, the division is less clear because a gas atmosphere may be significantly
eroded by stellar radiation.Comment: 41 pages in preprint style, 15 figures, final version accepted to Ap
From Select Agent to an Established Pathogen: The Response to \u3ci\u3ePhakopsora pachyrhizi\u3c/i\u3e (Soybean Rust) in North America
The pathogen causing soybean rust, Phakopsora pachyrhizi, was first described in Japan in 1902. The disease was important in the Eastern Hemisphere for many decades before the fungus was reported in Hawaii in 1994, which was followed by reports from countries in Africa and South America. In 2004, P. pachyrhizi was confirmed in Louisiana, making it the first report in the continental United States. Based on yield losses from countries in Asia, Africa, and South America, it was clear that this pathogen could have a major economic impact on the yield of 30 million ha of soybean in the United States. The response by agencies within the United States Department of Agriculture, industry, soybean check-off boards, and universities was immediate and complex. The impacts of some of these activities are detailed in this review. The net result has been that the once dreaded disease, which caused substantial losses in other parts of the world, is now better understood and effectively managed in the United States. The disease continues to be monitored yearly for changes in spatial and temporal distribution so that soybean growers can continue to benefit by knowing where soybean rust is occurring during the growing season
A Small Molecule That Binds and Inhibits the ETV1 Transcription Factor Oncoprotein
Members of the ETS transcription factor family have been implicated in several cancers, where they are often dysregulated by genomic derangement. ETS variant 1 (ETV1) is an ETS factor gene that undergoes chromosomal translocation in prostate cancers and Ewing sarcomas, amplification in melanomas, and lineage dysregulation in gastrointestinal stromal tumors. Pharmacologic perturbation of ETV1 would be appealing in these cancers; however, oncogenic transcription factors are often deemed “undruggable” by conventional methods. Here, we used small-molecule microarray screens to identify and characterize drug-like compounds that modulate the biologic function of ETV1. We identified the 1,3,5-triazine small molecule BRD32048 as a top candidate ETV1 perturbagen. BRD32048 binds ETV1 directly, modulating both ETV1-mediated transcriptional activity and invasion of ETV1-driven cancer cells. Moreover, BRD32048 inhibits p300-dependent acetylation of ETV1, thereby promoting its degradation. These results point to a new avenue for pharmacologic ETV1 inhibition and may inform a general means to discover small molecule perturbagens of transcription factor oncoproteins.National Cancer Institute (U.S.) (Initiative for Chemical Genetics Contract N01-CO-12400)National Cancer Institute (U.S.) (Cancer Target Discovery and Development Network RC2 CA148399
Abiotic formation of O2 and O3 in high-CO2 terrestrial atmospheres
Previous research has indicated that high amounts of ozone (O3) and oxygen
(O2) may be produced abiotically in atmospheres with high concentrations of
CO2. The abiotic production of these two gases, which are also characteristic
of photosynthetic life processes, could pose a potential "false-positive" for
remote-sensing detection of life on planets around other stars.We show here
that such false positives are unlikely on any planet that possesses abundant
liquid water, as rainout of oxidized species onto a reduced planetary surface
should ensure that atmospheric H2 concentrations remain relatively high, and
that O2 and O3 remain low. Our aim is to determine the amount of O3 and O2
formed in a high CO2 atmosphere for a habitable planet without life. We use a
photochemical model that considers hydrogen (H2) escape and a detailed hydrogen
balance to calculate the O2 and O3 formed on planets with 0.2 of CO2 around the
Sun, and 0.02, 0.2 and 2 bars of CO2 around a young Sun-like star with higher
UV radiation. The concentrations obtained by the photochemical model were used
as input in a radiative transfer model that calculated the spectra of the
modeled planets. The O3 and O2 concentrations in the simulated planets are
extremely small, and unlikely to produce a detectable signature in the spectra
of those planets. We conclude that with a balanced hydrogen budget, and for
planets with an active hydrological cycle, abiotic formation of O2 and O3 is
unlikely to create a possible false positive for life detection in either the
visible/near-infrared or mid-infrared wavelength regimes.Comment: 27 pages, 15 figures, Astronomy & Astrophysics accepte
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