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2.
Nature ; 610(7933): 687-692, 2022 10.
Article in English | MEDLINE | ID: mdl-36049503

ABSTRACT

The social cost of carbon dioxide (SC-CO2) measures the monetized value of the damages to society caused by an incremental metric tonne of CO2 emissions and is a key metric informing climate policy. Used by governments and other decision-makers in benefit-cost analysis for over a decade, SC-CO2 estimates draw on climate science, economics, demography and other disciplines. However, a 2017 report by the US National Academies of Sciences, Engineering, and Medicine1 (NASEM) highlighted that current SC-CO2 estimates no longer reflect the latest research. The report provided a series of recommendations for improving the scientific basis, transparency and uncertainty characterization of SC-CO2 estimates. Here we show that improved probabilistic socioeconomic projections, climate models, damage functions, and discounting methods that collectively reflect theoretically consistent valuation of risk, substantially increase estimates of the SC-CO2. Our preferred mean SC-CO2 estimate is $185 per tonne of CO2 ($44-$413 per tCO2: 5%-95% range, 2020 US dollars) at a near-term risk-free discount rate of 2%, a value 3.6 times higher than the US government's current value of $51 per tCO2. Our estimates incorporate updated scientific understanding throughout all components of SC-CO2 estimation in the new open-source Greenhouse Gas Impact Value Estimator (GIVE) model, in a manner fully responsive to the near-term NASEM recommendations. Our higher SC-CO2 values, compared with estimates currently used in policy evaluation, substantially increase the estimated benefits of greenhouse gas mitigation and thereby increase the expected net benefits of more stringent climate policies.


Subject(s)
Carbon Dioxide , Climate Models , Socioeconomic Factors , Carbon Dioxide/analysis , Carbon Dioxide/economics , Climate , Greenhouse Gases/analysis , Greenhouse Gases/economics , Uncertainty , Delay Discounting , Risk , Policy Making , Environmental Policy
3.
Sci Data ; 3: 160106, 2016 12 06.
Article in English | MEDLINE | ID: mdl-27922592

ABSTRACT

Earth-observing remote sensing data, including aerial photography and satellite imagery, offer a snapshot of the world from which we can learn about the state of natural resources and the built environment. The components of energy systems that are visible from above can be automatically assessed with these remote sensing data when processed with machine learning methods. Here, we focus on the information gap in distributed solar photovoltaic (PV) arrays, of which there is limited public data on solar PV deployments at small geographic scales. We created a dataset of solar PV arrays to initiate and develop the process of automatically identifying solar PV locations using remote sensing imagery. This dataset contains the geospatial coordinates and border vertices for over 19,000 solar panels across 601 high-resolution images from four cities in California. Dataset applications include training object detection and other machine learning algorithms that use remote sensing imagery, developing specific algorithms for predictive detection of distributed PV systems, estimating installed PV capacity, and analysis of the socioeconomic correlates of PV deployment.

4.
West J Emerg Med ; 17(2): 229-37, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26973757

ABSTRACT

In 2007, the Centers for Medicaid and Medicare Services (CMS) created a novel payment program to create incentives for physician's to focus on quality of care measures and report quality performance for the first time. Initially termed "The Physician Voluntary Reporting Program," various Congressional actions, including the Tax Relief and Health Care Act of 2006 (TRHCA) and Medicare Improvements for Patients and Providers Act of 2008 (MIPPA) further strengthened and ensconced this program, eventually leading to the quality program termed today as the Physician Quality Reporting System (PQRS). As a result of passage of the Affordable Care Act of 2010, the PQRS program has expanded to include both the "traditional PQRS" reporting program and the newer "Value Modifier" program (VM). For the first time, these programs were designed to include pay-for-performance incentives for all physicians providing care to Medicare beneficiaries and to measure the cost of care. The recent passage of the Medicare Access and Children's Health Insurance Program (CHIP) Reauthorization Act in March of 2015 includes changes to these payment programs that will have an even more profound impact on emergency care providers. We describe the implications of these important federal policy changes for emergency physicians.


Subject(s)
Emergency Medical Services/standards , Physicians/standards , Quality of Health Care/standards , Reimbursement, Incentive , Humans , Medicaid , Medicare , Patient Protection and Affordable Care Act , United States
6.
Science ; 344(6191): 1460-1, 2014 Jun 27.
Article in English | MEDLINE | ID: mdl-24970072
7.
Environ Sci Technol ; 48(15): 8360-8, 2014.
Article in English | MEDLINE | ID: mdl-24754840

ABSTRACT

Advances in technologies for extracting oil and gas from shale formations have dramatically increased U.S. production of natural gas. As production expands domestically and abroad, natural gas prices will be lower than without shale gas. Lower prices have two main effects: increasing overall energy consumption, and encouraging substitution away from sources such as coal, nuclear, renewables, and electricity. We examine the evidence and analyze modeling projections to understand how these two dynamics affect greenhouse gas emissions. Most evidence indicates that natural gas as a substitute for coal in electricity production, gasoline in transport, and electricity in buildings decreases greenhouse gases, although as an electricity substitute this depends on the electricity mix displaced. Modeling suggests that absent substantial policy changes, increased natural gas production slightly increases overall energy use, more substantially encourages fuel-switching, and that the combined effect slightly alters economy wide GHG emissions; whether the net effect is a slight decrease or increase depends on modeling assumptions including upstream methane emissions. Our main conclusions are that natural gas can help reduce GHG emissions, but in the absence of targeted climate policy measures, it will not substantially change the course of global GHG concentrations. Abundant natural gas can, however, help reduce the costs of achieving GHG reduction goals.


Subject(s)
Climate Change , Extraction and Processing Industry , Natural Gas , Air Pollutants , Air Pollution/prevention & control , Methane , United States
8.
Science ; 343(6177): 1316-7, 2014 Mar 21.
Article in English | MEDLINE | ID: mdl-24653022
9.
Ann R Coll Surg Engl ; 92(1): 19-22, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20056054

ABSTRACT

A midline approach to the lumbar region is most frequently used for posterior lumbar spine surgery. The exposure of the deeper layer of muscles, however, is imprecise and can entail substantial tissue damage and blood loss. During 10 years of operative surgical experience, we have developed an improved and less traumatic technique for exposure of the lumbar transverse processes and intertransverse region in which the tendons of multifidus and longissimus muscles are isolated at every level and divided laterally to the facet joints. This method eases identification and accurate cauterisation of the subjacent arteries, thereby reducing tissue damage and blood loss. It takes no more time and clarifies the exposure of the lumbar transverse processes and intertransverse region. Cadaveric dissection confirms the muscular and arterial anatomy of the region. We recommend use of this modified approach to improve standard practice.


Subject(s)
Lumbar Vertebrae/surgery , Muscle, Skeletal/anatomy & histology , Arteries/anatomy & histology , Blood Loss, Surgical/prevention & control , Cadaver , Dissection/methods , Hemostasis, Surgical , Humans , Lumbar Vertebrae/blood supply , Muscle, Skeletal/surgery
10.
Environ Sci Technol ; 43(6): 1962-9, 2009 Mar 15.
Article in English | MEDLINE | ID: mdl-19368199

ABSTRACT

Carbon sequestration in sandstone saline reservoirs holds great potential for mitigating climate change, but its storage potential and cost per ton of avoided CO2 emissions are uncertain. We develop a general model to determine the maximum theoretical constraints on both storage potential and injection rate and use it to characterize the economic viability of geosequestration in sandstone saline aquifers. When applied to a representative set of aquifer characteristics, the model yields results that compare favorably with pilot projects currently underway. Over a range of reservoir properties, maximum effective storage peaks at an optimal depth of 1600 m, at which point 0.18-0.31 metric tons can be stored per cubic meter of bulk volume of reservoir. Maximum modeled injection rates predict minima for storage costs in a typical basin in the range of $2-7/ ton CO2 (2005 U.S.$) depending on depth and basin characteristics in our base-case scenario. Because the properties of natural reservoirs in the United States vary substantially, storage costs could in some cases be lower or higher by orders of magnitude. We conclude that available geosequestration capacity exhibits a wide range of technological and economic attractiveness. Like traditional projects in the extractive industries, geosequestration capacity should be exploited starting with the low-cost storage options first then moving gradually up the supply curve.


Subject(s)
Carbon Dioxide/chemistry , Sodium Chloride/chemistry , Water/chemistry , Geological Phenomena , Greenhouse Effect , Models, Chemical , Models, Economic , Water Supply/analysis
12.
J Appl Toxicol ; 28(5): 703-9, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18059068

ABSTRACT

Androstenedione, a naturally occurring steroid hormone, has been used to enhance athletic performance. Little is known, however, about its hepatotoxicity. Clone-9 cells, a non-transformed epithelial cell line that was originally isolated from normal liver of a 4-week old Sprague-Dawley rat, were used as an in vitro model to assess the hepatotoxic potential of androstenedione. The cultures were treated with androstenedione for 24 h at 37 degrees C in 5% CO(2) at concentrations of 0-100 microg ml(-1). After the treatment period, the cells and the culture supernatants were assayed for markers of cytotoxicity which included: release of liver enzymes, cell viability, cellular double-stranded DNA content, oxidative stress, steatosis, cellular ATP content, caspase-3 activity, the mitochondrial permeability transition and induction of cytochrome P450 activity. Significant concentration-dependent differences from control were observed in some endpoints at medium concentrations of 10 microg ml(-1) and above. These in vitro findings were compared with comparable endpoints obtained from an in vivo study of androstenedione toxicity in female Sprague-Dawley rats. Of the eight endpoints that could be compared between the two studies, only three (lipid accumulation, ATP depletion and P450 activity) appeared to be concordant. This suggests that, under the experimental conditions used, the clone-9 cells were not a good model for androstenedione hepatotoxicity.


Subject(s)
Androstenedione/toxicity , Chemical and Drug Induced Liver Injury/pathology , Adenosine Triphosphate/metabolism , Animals , Biomarkers , Caspase 3/metabolism , Cell Line , Clone Cells , DNA/biosynthesis , DNA/genetics , Enzymes/blood , Enzymes/metabolism , Female , Hepatocytes/drug effects , Hepatocytes/enzymology , Liver/cytology , Liver/drug effects , Liver/pathology , Models, Biological , Oxidative Stress/drug effects , Rats , Rats, Sprague-Dawley , Reproducibility of Results
13.
Clin Anat ; 18(1): 39-45, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15597371

ABSTRACT

It has been proposed that the superficial part of the portal fissures weakens the surface hepatic parenchyma, allowing the development of accessory sulci caused by diaphragmatic pressure. To evaluate the relationship of the sulci in the antero-superior surface of the right liver with the right portal fissure, macroscopic post mortem examination of 85 livers was carried out and radio-opaque resins were injected into the portal and hepatic venous systems to obtain vascular casts. After formalin fixation, the 85 livers also underwent CT and MR scans and 3D image elaboration. Diaphragmatic sulci were found in 32 cases. We studied the sulci located in the right liver, i.e., those that lay to the right of the line of Cantlie. They were found in 28 instances and in 16 cases they were multiple. In the livers with a single sulcus, it extended between the anterior and right surfaces of the right liver and showed a curved course downward and forward, toward the inferior margin. In the cases with multiple sulci, one sulcus always showed a course similar to that of the single sulci. The 28 sulci, with similar position and course, showed variable characteristics (mean length=7.6 +/- 2.7 cm, mean width=0.8 +/- 0.7 cm, mean depth=1.4 +/- 0.8 cm). Both radiological images and corrosion casts showed a correspondence between these sulci and the right hepatic vein and the right portal fissure in 71% of cases. These sulci may represent the variable expression (cranial, intermediate, or caudal portions) of a potential sulcus, the main accessory sulcus (MAS), that develops along a theoretically predictable course corresponding to the superficial part of the right portal fissure. The high prevalence of location of the MAS at the level of the upper part of the right portal fissure can be ascribed to the presence at this level of the watershed between the roots of the tributaries of the hepatic veins coming from segments VIII and VII, draining respectively into the middle and right hepatic veins. Thus, the coexistence of the two portal and hepatic venous boundaries may represent a further predisposition to the effects of diaphragmatic pressure. The MAS may represent a marking for the right portal fissure, and hence a superficial reference for the deep course of the right hepatic vein.


Subject(s)
Hepatic Veins/anatomy & histology , Liver/anatomy & histology , Portal Vein/anatomy & histology , Portography/methods , Adult , Aged , Corrosion Casting , Female , Humans , Imaging, Three-Dimensional , Liver/diagnostic imaging , Liver Circulation , Magnetic Resonance Imaging , Male , Middle Aged , Tomography, X-Ray Computed
15.
AJR Am J Roentgenol ; 182(2): 431-9, 2004 Feb.
Article in English | MEDLINE | ID: mdl-14736677

ABSTRACT

OBJECTIVE: The surgical removal of a rectal carcinoma and the adjacent lymph nodes in an en bloc package lessens the risk of local recurrence due to residual tumor. Heightened awareness of good surgical techniques has created much interest in the anatomy involved in total mesorectal excision surgery, with particular focus on the fascial planes and nerve plexuses and their relationship to the surgical planes of excision. Clear preoperative depiction of these relationships is of value in determining tumor resectability. The aim of this study was to describe the radiologic appearance of these anatomic structures. SUBJECTS AND METHODS. High-spatial-resolution T2-weighted MRI was performed using a 1.5-T system in cadaveric sections and in patients before they underwent total mesorectal excision surgery. Anatomic dissections of sagitally sectioned hemipelves were compared with MRIs obtained in vivo to establish criteria for visualization of the structures relevant to anterior resection of the rectum. RESULTS: High-spatial-resolution MRI depicted a number of structures of importance in total mesorectal excision surgery. The mesorectal fascia, which forms the boundary of the surgical excision plane in total mesorectal excision, was identified, and the presacral fascia, peritoneal reflection, and Denonvilliers' fascia were also shown. Structures 1-2 mm in diameter were visualized because the contrast resolution afforded by T2-weighted fast spin-echo imaging permitted depiction of the inferior hypogastric nerve plexus and the fascial planes within the posterior pelvis. CONCLUSION: Anatomic landmarks important to the performance of rectal cancer surgery, in particular the mesorectal fascia, may be defined on MRI and are of potential importance in the staging of tumors, assessing resectability, planning surgery, and selecting patients for preoperative neoadjuvant therapy.


Subject(s)
Fascia/pathology , Rectal Neoplasms/pathology , Rectum/pathology , Aged , Digestive System Surgical Procedures , Dissection , Female , Humans , Image Enhancement , Magnetic Resonance Imaging/methods , Male , Middle Aged , Rectal Neoplasms/surgery , Rectum/anatomy & histology , Rectum/surgery , Treatment Outcome
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