288 research outputs found
An analysis of Australia's carbon pollution reduction scheme
The authors review the decision-making since the Labour Government came into office (November 2007). The Australian Governmentâs âCarbon Pollution Reduction Schemeâ White Paper (15 December 2008) proposes that an Australian Emissions Trading Scheme (AETS) be implemented in mid-2010. Acknowledging that the scheme is comprehensive, the paper finds that in many cases, Australia will take a softer approach to climate change through the AETS than the European Union ETS(EUETS). The paper assesses key issues in the White Paper such as emissions reduction targets, GHG coverage, sectoral coverage, inclusion of unlimited quantities of offsets from Kyoto international markets and exclusion of deforestation activities
Delocalization and spin-wave dynamics in ferromagnetic chains with long-range correlated random exchange
We study the one-dimensional quantum Heisenberg ferromagnet with exchange
couplings exhibiting long-range correlated disorder with power spectrum
proportional to , where is the wave-vector of the modulations
on the random coupling landscape. By using renormalization group, integration
of the equations of motion and exact diagonalization, we compute the spin-wave
localization length and the mean-square displacement of the wave-packet. We
find that, associated with the emergence of extended spin-waves in the
low-energy region for , the wave-packet mean-square displacement
changes from a long-time super-diffusive behavior for to a
long-time ballistic behavior for . At the vicinity of ,
the mobility edge separating the extended and localized phases is shown to
scale with the degree of correlation as .Comment: PRB to appea
Economic Implications of Biological Control of Arundo donax in the Texas Rio Grande Basin
ABSTRACT
Arundo donax, or giant reed, is a large, bamboo-like plant that is native to Spain and has invaded
several thousand acres of the Rio Grande riparian zone in Texas and Mexico. The plant grows to
over 26 feet tall, and consumes large quantities of water, estimated as an amount equivalent to
about 11% of irrigation water diverted by Valley irrigation districts (i.e., some estimates are more
than 5.5 acre-feet per acre). With concern of increased water demands in the Texas Lower Rio
Grande Valley region, the United States Department of Agriculture, Agricultural Research
Service (USDA)ARS) is investigating four herbivorous insects as potential biological control
agents for Arundo donax to facilitate increased water supply.
This study examines selected economic implications for agricultural water users in the United
States of applying these biological control agents along the Rio Grande. The research includes
(a) estimating the value of the water saved due to the reduction of Arundo donax, (b) a benefit
-cost analyses, (c) regional economic impact analyses, and (d) an estimate of the per-unit cost of
water saved over a 50-year planning horizon (2009 through 2058). The model ArundoEcon© is
used to perform a baseline deterministic analyses using low- and high-value irrigated composite
acre values. That is, the saved water is initially valued based on being applied to agriculture as
irrigation. Since the actual crop mix irrigated with the saved water is unknown, a range is
provided by assuming all irrigated crops are âlow-value,â and then again by including both âlowvalueâ
and âhigh-valueâ irrigated crops.
Results of the water amount saved are 2/9 of the amount consumed, or approximately one acrefoot
of water for each acre of Arundo. For each acre-foot of water saved, 1.85 dryland acres can
be converted to low-value crop acres, and 0.71 can be converted to high-value crop acres.
Regional economic results indicate a present value of farm-level benefits ranging from 160 million. Benefit-cost ratios are calculated with normalized prices and indicate a range from
4.38 to 8.81. Sensitivity analyses provide a robust set of results for Arundo agricultural water
use, effectiveness of control agents, replacement speciesâ water use, Arundo expansion rate after
control, value of water, and the cost of the program.
The pre-production processes and farm-gate economic impact analyses are estimated using
multipliers from the IMPLAN model. Regional results reveal a range of 18 million
annually in economic output and 197 to 351 jobs associated with the increase in gross revenues
due to the control of Arundo donax for the year 2025. Values for other select years are also
provided. Further results suggest a life-cycle cost per acre-foot of water saved of $44. This
amount is comparable to other projects designed to conserve water in the region.
The USDA)ARS, Weslaco, Texas Arundo donax biological control project will realize positive
results as indicated by the benefit-cost ratios, economic impact analyses, and competitive results
for the per-unit cost of saving water. These results indicate this project will have positive
economic implications for the U.S. and the Texas Lower Rio Grande Valley
Deletion variants of middle east respiratory syndrome coronavirus from humans, Jordan, 2015
We characterized Middle East respiratory syndrome coronaviruses from a hospital outbreak in Jordan in 2015. The viruses from Jordan were highly similar to isolates from Riyadh, Saudi Arabia, except for deletions in open reading frames 4a and 3. Transmissibility and pathogenicity of this strain remains to be determined
Cancer Incidence, Mortality, Years of Life Lost, Years Lived With Disability, and Disability-Adjusted Life Years for 29 Cancer Groups From 2010 to 2019: A Systematic Analysis for the Global Burden of Disease Study 2019
Published online December 30, 2021.Importance: The Global Burden of Diseases, Injuries, and Risk Factors Study 2019 (GBD 2019) provided systematic estimates of incidence, morbidity, and mortality to inform local and international efforts toward reducing cancer burden. Objective: To estimate cancer burden and trends globally for 204 countries and territories and by Sociodemographic Index (SDI) quintiles from 2010 to 2019. Evidence review: The GBD 2019 estimation methods were used to describe cancer incidence, mortality, years lived with disability, years of life lost, and disability-adjusted life years (DALYs) in 2019 and over the past decade. Estimates are also provided by quintiles of the SDI, a composite measure of educational attainment, income per capita, and total fertility rate for those younger than 25 years. Estimates include 95% uncertainty intervals (UIs). Findings: In 2019, there were an estimated 23.6 million (95% UI, 22.2-24.9 million) new cancer cases (17.2 million when excluding nonmelanoma skin cancer) and 10.0 million (95% UI, 9.36-10.6 million) cancer deaths globally, with an estimated 250 million (235-264 million) DALYs due to cancer. Since 2010, these represented a 26.3% (95% UI, 20.3%-32.3%) increase in new cases, a 20.9% (95% UI, 14.2%-27.6%) increase in deaths, and a 16.0% (95% UI, 9.3%-22.8%) increase in DALYs. Among 22 groups of diseases and injuries in the GBD 2019 study, cancer was second only to cardiovascular diseases for the number of deaths, years of life lost, and DALYs globally in 2019. Cancer burden differed across SDI quintiles. The proportion of years lived with disability that contributed to DALYs increased with SDI, ranging from 1.4% (1.1%-1.8%) in the low SDI quintile to 5.7% (4.2%-7.1%) in the high SDI quintile. While the high SDI quintile had the highest number of new cases in 2019, the middle SDI quintile had the highest number of cancer deaths and DALYs. From 2010 to 2019, the largest percentage increase in the numbers of cases and deaths occurred in the low and low-middle SDI quintiles. Conclusions and relevance: The results of this systematic analysis suggest that the global burden of cancer is substantial and growing, with burden differing by SDI. These results provide comprehensive and comparable estimates that can potentially inform efforts toward equitable cancer control around the world.The Global Burden of Disease Cancer Collaboration ... Kocarnik, Jonathan M ... Olagunju, Andrew T ... Tessema, Gizachew A ... et al
Multihospital Outbreak of a Middle East Respiratory Syndrome Coronavirus Deletion Variant, Jordan: A Molecular, Serologic, and Epidemiologic Investigation
Background
An outbreak of Middle East respiratory syndrome coronavirus (MERS-CoV) in Jordan in 2015 involved a variant virus that acquired distinctive deletions in the accessory open reading frames. We conducted a molecular and seroepidemiologic investigation to describe the deletion variantâs transmission patterns and epidemiology.
Methods
We reviewed epidemiologic and medical chart data and analyzed viral genome sequences from respiratory specimens of MERS-CoV cases. In early 2016, sera and standardized interviews were obtained from MERS-CoV cases and their contacts. Sera were evaluated by nucleocapsid and spike protein enzyme immunoassays and microneutralization.
Results
Among 16 cases, 11 (69%) had health care exposure and 5 (31%) were relatives of a known case; 13 (81%) were symptomatic, and 7 (44%) died. Genome sequencing of MERS-CoV from 13 cases revealed 3 transmissible deletions associated with clinical illness during the outbreak. Deletion variant sequences were epidemiologically clustered and linked to a common transmission chain. Interviews and sera were collected from 2 surviving cases, 23 household contacts, and 278 health care contacts; 1 (50%) case, 2 (9%) household contacts, and 3 (1%) health care contacts tested seropositive.
Conclusions
The MERS-CoV deletion variants retained human-to-human transmissibility and caused clinical illness in infected persons despite accumulated mutations. Serology suggested limited transmission beyond that detected during the initial outbreak investigation
Search for Gravitational Waves Associated with Gamma-Ray Bursts Detected by Fermi and Swift during the LIGO-Virgo Run O3b
We search for gravitational-wave signals associated with gamma-ray bursts (GRBs) detected by the Fermi and Swift satellites during the second half of the third observing run of Advanced LIGO and Advanced Virgo (2019 November 1 15:00 UTC-2020 March 27 17:00 UTC). We conduct two independent searches: A generic gravitational-wave transients search to analyze 86 GRBs and an analysis to target binary mergers with at least one neutron star as short GRB progenitors for 17 events. We find no significant evidence for gravitational-wave signals associated with any of these GRBs. A weighted binomial test of the combined results finds no evidence for subthreshold gravitational-wave signals associated with this GRB ensemble either. We use several source types and signal morphologies during the searches, resulting in lower bounds on the estimated distance to each GRB. Finally, we constrain the population of low-luminosity short GRBs using results from the first to the third observing runs of Advanced LIGO and Advanced Virgo. The resulting population is in accordance with the local binary neutron star merger rate. © 2022. The Author(s). Published by the American Astronomical Society
Narrowband Searches for Continuous and Long-duration Transient Gravitational Waves from Known Pulsars in the LIGO-Virgo Third Observing Run
Isolated neutron stars that are asymmetric with respect to their spin axis are possible sources of detectable continuous gravitational waves. This paper presents a fully coherent search for such signals from eighteen pulsars in data from LIGO and Virgo's third observing run (O3). For known pulsars, efficient and sensitive matched-filter searches can be carried out if one assumes the gravitational radiation is phase-locked to the electromagnetic emission. In the search presented here, we relax this assumption and allow both the frequency and the time derivative of the frequency of the gravitational waves to vary in a small range around those inferred from electromagnetic observations. We find no evidence for continuous gravitational waves, and set upper limits on the strain amplitude for each target. These limits are more constraining for seven of the targets than the spin-down limit defined by ascribing all rotational energy loss to gravitational radiation. In an additional search, we look in O3 data for long-duration (hours-months) transient gravitational waves in the aftermath of pulsar glitches for six targets with a total of nine glitches. We report two marginal outliers from this search, but find no clear evidence for such emission either. The resulting duration-dependent strain upper limits do not surpass indirect energy constraints for any of these targets. © 2022. The Author(s). Published by the American Astronomical Society
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