1,324 research outputs found
Expression of baculovirus P35 prevents cell death in Drosophila
The baculovirus P35 protein functions to prevent apoptotic death of infected cells. We have expressed P35 in the developing embryo and eye of the fly Drosophila melanogaster. P35 eliminates most, if not all, normally occurring cell death in these tissues, as well as X-irradiation-induced death. Excess pupal eye cells that are normally eliminated by apoptosis develop into pigment cells when their death is prevented by P35 expression. Our results suggest that one mechanism by which viruses prevent the death of the host cell is to block a cell death pathway that mediates normally occurring cell death. Identification of molecules that interact biochemically or genetically with P35 in Drosophila should provide important insights into how cell death is regulated
Greenhouse Gas Impacts of Ethanol from Iowa Corn: Life Cycle Analysis Versus System-Wide Accounting
Life cycle analysis (LCA) is the standard approach used to evaluate the greenhouse gas (GHG) benefits of biofuels. However, it is increasingly recognized that LCA results do not account for some impacts-including land use changes-that have important implications on GHGs. Thus, an alternative accounting system that goes beyond LCA is needed. In this paper, we contribute to the literature by laying out the basics of a system-wide accounting (SWA) method that takes into account all potential changes in GHGs resulting from biofuel expansion. We applied both LCA and SWA to assess the GHG impacts of ethanol based on Iowa corn. Growing corn in rotation with soybeans generated 35% less GHG emissions than growing corn after corn. Based on average corn production, ethanol's GHG benefits were lower in 2007 than in 2006 because of an increase in continuous corn in 2007. When only additional corn was considered, ethanol emitted about 22% less GHGs than gasoline. Results from SWA varied with the choice of baseline and the definition of geographical boundaries. Using 2006 as a baseline and 2007 as a scenario, corn ethanol's benefits were about 20% of the emissions of gasoline. If we expand geographical limits beyond Iowa, but assume the same emission rates for soybean production and land use changes as those in Iowa, then corn ethanol generated more GHG emissions than gasoline. These results highlight the importance of boundary definition for both LCA and SWA.biofuels; corn ethanol; greenhouse gas; life cycle analysis; system-wide accounting
Secretion properties, clearance, and therapy in airway disease
Chronic airway diseases like cystic fibrosis, chronic bronchitis, asthma, diffuse panbronchiolitis, and bronchiectasis are all associated with chronic inflammation. The airway mucosa responds to infection and inflammation in part by surface mucous (goblet) cell and submucosal gland hyperplasia and hypertrophy with mucus hypersecretion. Products of inflammation including neutrophil derived DNA and filamentous actin, effete cells, bacteria, and cell debris all contribute to mucus purulence and, when this is expectorated it is called sputum. Mucus is usually cleared by ciliary movement, and sputum is cleared by cough.
These airway diseases each are associated with the production of mucus and sputum with characteristic composition, polymer structure, and biophysical properties. These properties change with the progress of the disease making it possible to use sputum analysis to identify the potential cause and severity of airway diseases. This information has also been important for the development of effective mucoactive therapy to promote airway hygiene
A process-oriented language for describing aspects of reading comprehension
Includes bibliographical references (p. 36-38)The research described herein was supported in part by the National Institute of Education under Contract No. MS-NIE-C-400-76-011
Greenhouse Gas Impacts of Ethanol from Iowa Corn: Life Cycle Analysis versus System-wide Accounting
Life cycle analysis (LCA) is the standard approach used to evaluate the greenhouse gas (GHG) benefits of biofuels. However, it is increasingly recognized that LCA results do not account for some impacts including land use changes that have important implications on GHGs. Thus, an alternative accounting system that goes beyond LCA is needed. In this paper, we contribute to the literature by laying out the basics of a system-wide accounting (SWA) method that takes into account all potential changes in GHGs resulting from biofuel expansion. We applied both LCA and SWA to assess the GHG impacts of ethanol based on Iowa corn. Growing corn in rotation with soybeans generated 35% less GHG emissions than growing corn after corn. Based on average corn production, ethanol's GHG benefits were lower in 2007 than in 2006 because of an increase in continuous corn in 2007. When only additional corn was considered, ethanol emitted about 22% less GHGs than gasoline. Results from SWA varied with the choice of baseline and the definition of geographical boundaries. Using 2006 as a baseline and 2007 as a scenario, corn ethanol's benefits were about 20% of the emissions of gasoline. If we expand geographical limits beyond Iowa, but assume the same emission rates for soybean production and land use changes as those in Iowa, then corn ethanol generated more GHG emissions than gasoline. These results highlight the importance of boundary definition for both LCA and SWAbiofuels, corn ethanol, greenhouse gas, life cycle analysis, system-wide accounting, Research Methods/ Statistical Methods, Resource /Energy Economics and Policy,
Credit Enhancement Strategies for Higher Efficiency Vehicles in Maine
Credit enhancements are a necessary, but not sufficient policy tool to expand access to clean, reliable vehicles. They are necessary because lower-income and historically disadvantaged groups have less access to low-cost financing. They are not sufficient in that credit enhancements alone, while helpful, are not likely to substantially increase the purchase of clean, reliable vehicles with a higher initial purchase price, but comparable or lower long-term cost of ownership. We review two credit enhancement mechanisms: loan loss reserves and interest rate buy-downs
Using TIPS to Discount to Present Value
The practice of forensic economics has a long history of trying to identify the correct interest rate to use when valuing economic losses in personal injury and wrongful death cases. We trace the legal history as it relates to the appropriate interest rates and adjustments for inflation. We then discuss the use of Treasury Inflation Protected Securities, TIPS, and an analysis of the combined effect of realized inflation and taxes on the effective return. We come to the unexpected conclusion that the use of TIPS does not lend itself to a simple adjustment to the rate for taxes nor eliminate the need to consider expected inflation
Greenhouse gas impacts of ethanol from Iowa corn: Life cycle assessment versus system wide approach
Life cycle assessment (LCA) is the standard approach used to evaluate the greenhouse gas (GHG) benefits of biofuels. However, the need for the appropriate use of LCA in policy contexts is highlighted by recent findings that corn-based ethanol may actually increase GHG emissions. This is in contrary to most existing LCA results. LCA estimates can vary across studies due to heterogeneities in inputs and production technology. Whether marginal or average impacts are considered can matter as well. Most important of all, LCA is product-centered. The determination of the impact of biofuels expansion requires a system wide approach (SWA) that accounts for impacts on all affected products and processes. This paper presents both LCA and SWA for ethanol based on Iowa corn. LCA was conducted in several different ways. Growing corn in rotation with soybean generates 35% less GHG emissions than growing corn after corn. Based on average corn production, ethanol\u27s GHG benefits were lower in 2007 than in 2006 because of an increase in continuous corn in 2007. When only additional corn was considered, ethanol emitted about 22% less GHGs than gasoline. SWA was applied to two simple cases. Using 2006 as a baseline and 2007 as a scenario, corn ethanol\u27s benefits were about 20% of the emissions of gasoline. If geographical limits are expanded beyond Iowa, then corn ethanol could generate more GHG emissions than gasoline. These results highlight the importance of boundary definition for both LCA and SWA
Application of Bayesian graphs to SN Ia data analysis and compression
Bayesian graphical models are an efficient tool for modelling complex data
and derive self-consistent expressions of the posterior distribution of model
parameters. We apply Bayesian graphs to perform statistical analyses of Type Ia
supernova (SN Ia) luminosity distance measurements from the joint light-curve
analysis (JLA) data set. In contrast to the approach used in previous
studies, the Bayesian inference allows us to fully account for the
standard-candle parameter dependence of the data covariance matrix. Comparing
with analysis results, we find a systematic offset of the marginal
model parameter bounds. We demonstrate that the bias is statistically
significant in the case of the SN Ia standardization parameters with a maximal
6 shift of the SN light-curve colour correction. In addition, we find
that the evidence for a host galaxy correction is now only 2.4 .
Systematic offsets on the cosmological parameters remain small, but may
increase by combining constraints from complementary cosmological probes. The
bias of the analysis is due to neglecting the parameter-dependent
log-determinant of the data covariance, which gives more statistical weight to
larger values of the standardization parameters. We find a similar effect on
compressed distance modulus data. To this end, we implement a fully consistent
compression method of the JLA data set that uses a Gaussian approximation of
the posterior distribution for fast generation of compressed data. Overall, the
results of our analysis emphasize the need for a fully consistent Bayesian
statistical approach in the analysis of future large SN Ia data sets.Comment: 14 pages, 13 figures, 5 tables. Submitted to MNRAS. Compression
utility available at https://gitlab.com/congma/libsncompress/ and example
cosmology code with machine-readable version of Tables A1 & A2 at
https://gitlab.com/congma/sn-bayesian-model-example/ v2: corrected typo in
author's name. v3: 15 pages, incl. corrections, matches the accepted versio
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