Evaluation of conventional power systems

The technical, economic, and environmental characteristics of (thermal, nonsolar) electric power plants are reviewed. The fuel cycle, from extraction of new fuel to final waste management, is included. Emphasis is placed on the fossil fuel and nuclear technologies

A decision analytical framework for evaluating technical innovation and diffusion: The case of electronic ballasts for commercial buildings

The authors present a decision analytical framework for studying the decision to purchase new energy-efficient magnetic ballasts for commercial buildings as a special case study for understanding the decision environment that could either encourage or retard the penetration of new carbon-saving technologies. The framework is particularly germane to situations where uncertainty in the investment outcome prevails as a dominant dimension of the problem. It allows the policy analyst to consider policies that operate through other considerations than through the price alone. A key effect is how a policy will either truncate a probability distribution to remove the worst outcomes or cause the probability distribution to narrow. Such considerations appear important when studying information programs, vendor warranty, and other factors that condition the investment decision

Integrated Climate-Change Assessment Scenarios and Carbon Dioxide Removal

To halt climate change this century, we must reduce carbon dioxide (CO2) emissions from human activities to net zero. Any emission sources, such as in the energy or land-use sectors, must be balanced by natural or technological carbon sinks that facilitate CO2 removal (CDR) from the atmosphere. Projections of demand for large-scale CDR are based on an integrated scenario framework for emission scenarios composed of emission profiles as well as alternative socio-economic development trends and social values consistent with them. The framework, however, was developed years before systematic reviews of CDR entered the literature. This primer provides an overview of the purposes of scenarios in climate-change research and how they are used. It also introduces the integrated scenario framework and why it came about. CDR studies using the scenario framework, as well as its limitations, are discussed. Possible future developments for the scenario framework are highlighted, especially in relation to CDR

Normothermic Ex Vivo Lung Perfusion (Novel) as an Assessment of Extended Criteria Donor Lungs: A Prospective Multi-Center Clinical Trial

Purpose: Ex vivo lung perfusion (EVLP) allows re-evaluation of extended criteria/marginal donor lungs. This can increase the number of lung transplants. However, the long-term outcomes of transplanting EVLP-screened lungs in a multicenter setting are unknown. We proposed to evaluate the short- and long-term outcomes of EVLP performed at multiple centers. Methods: This is a prospective, nonrandomized clinical trial. Seventeen lung transplant centers in the United States. Adult patients with end-stage pulmonary disease requiring lung transplant from May 2011 to December 2017 were eligible. Lung allografts initially deemed extended criteria/marginal (n=216) were placed on EVLP and re-evaluated prior to transplant. Patients received either standard donors (n=116) or lungs screened with EVLP (n=110). Results: Half of the lung grafts (110/216, 50.9%) placed on EVLP were transplanted. The incidence of primary graft dysfunction 24 hours post-transplant was higher in the EVLP group (25.5% vs 10.3%, p=0.003), but was not significantly different 48 hours (EVLP: 15.5%, control: 9.5%, p=0.49) and 72 hours (13.6% vs 6.9%, p=0.34) post-transplant. Survival was not significantly different between the 2 groups 1 year (n=226, EVLP: 86%, control: 94%, p=0.06), 3 years (n=226, EVLP: 68%, control: 76%, p=0.16, Figure), or 5 years (n=159, EVLP: 59%, control: 65%, p=0.68) post-transplant. There were also no differences in pulmonary function, the incidence of chronic lung allograft dysfunction or quality of life measures post-transplant. Conclusion: In this multicenter study, recipients of lungs that were re-evaluated on EVLP and deemed suitable for transplant had similar outcomes as a recipients of a standard lung transplants. EVLP offers the opportunity to screen donated lungs initially considered high risk and can safely increase the availability of transplantable lungs without compromising outcomes

The SDSS-III Baryon Oscillation Spectroscopic Survey: Quasar Target Selection for Data Release Nine

The SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS), a five-year spectroscopic survey of 10,000 deg^2, achieved first light in late 2009. One of the key goals of BOSS is to measure the signature of baryon acoustic oscillations in the distribution of Ly-alpha absorption from the spectra of a sample of ~150,000 z>2.2 quasars. Along with measuring the angular diameter distance at z\approx2.5, BOSS will provide the first direct measurement of the expansion rate of the Universe at z > 2. One of the biggest challenges in achieving this goal is an efficient target selection algorithm for quasars over 2.2 < z < 3.5, where their colors overlap those of stars. During the first year of the BOSS survey, quasar target selection methods were developed and tested to meet the requirement of delivering at least 15 quasars deg^-2 in this redshift range, out of 40 targets deg^-2. To achieve these surface densities, the magnitude limit of the quasar targets was set at g <= 22.0 or r<=21.85. While detection of the BAO signature in the Ly-alpha absorption in quasar spectra does not require a uniform target selection, many other astrophysical studies do. We therefore defined a uniformly-selected subsample of 20 targets deg^-2, for which the selection efficiency is just over 50%. This "CORE" subsample will be fixed for Years Two through Five of the survey. In this paper we describe the evolution and implementation of the BOSS quasar target selection algorithms during the first two years of BOSS operations. We analyze the spectra obtained during the first year. 11,263 new z>2.2 quasars were spectroscopically confirmed by BOSS. Our current algorithms select an average of 15 z > 2.2 quasars deg^-2 from 40 targets deg^-2 using single-epoch SDSS imaging. Multi-epoch optical data and data at other wavelengths can further improve the efficiency and completeness of BOSS quasar target selection. [Abridged]Comment: 33 pages, 26 figures, 12 tables and a whole bunch of quasars. Submitted to Ap