9,159 research outputs found
System scaling approach and thermoeconomic analysis of a pressure retarded osmosis system for power production with hypersaline draw solution: A Great Salt Lake study
pre-printOsmotic power with pressure retarded osmosis (PRO) is an emerging renewable energy option for locations where fresh water and salt water mix. Energy can be recovered from the salinity gradient between the solutions. This study provides a comprehensive feasibility analysis for a PRO power plant in a hypersaline environment. A sensitivity analysis investigates the effects of key technical and financial parameters on energy and economic performances. A case study is developed for the Great Salt Lake in Utah, USA (which has an average 24% salt concentration). A 25 MW PRO power plant is investigated to analyze the necessary components and their performances. With currently available technologies, the power plant would require 1.54 m3/s (24,410 GPM) fresh water flow rate and 3.08 m3/s (48,820 GPM) salt water flow rate. The net annual energy production is projected to be 154,249 MWh, with capital cost of 35.5 million per year. The levelized cost of electricity (LCOE) would be 0.1034/kWh. The high salinity of the Great Salt Lake is a critical factor toward making the osmotic power plant economically feasible
Evaluation of renewable energy technologies and their potential for technical integration and cost-effective use within the U.S. energy sector
pre-printEnergy demands, environmental impacts of energy conversion, and the depletion of fossil; fuels are constant topics of discussion in the energy industry. Renewable energy technologies; have been proposed for many years to address these concerns. However, the transformation; from traditional methods of power generation, usually based on fossil fuels, to power generation; based on renewable resources presents many challenges associated with emerging, or; less established, technologies. This paper examines the role of renewable energy in the U.S.; and its potential to meet current and future energy needs in a way that is technically and; economically sound. Renewable energy technologies, ranging from well-developed and established; to new and emerging technologies, are presented in terms of their technical potential,; current state of the technology, potential for further growth, and economic potential. While; renewable energy sources are abundant across the U.S., issues of dispatchability, variability,; scalability, energy storage, geographic limitations, and investment costs are critical in determining; future progress. The analysis in this paper can be used to guide the integration; of renewable energy systems toward becoming a larger share of energy production
Sugarcane mosaic virus infects Stenotaphrum secundatum in Australia
This study presents the first report of sugarcane mosaic virus (SCMV) infecting Stenotaphrum secundatum (buffalo grass) in Australia, from a turf farm in the Hunter Valley, New South Wales. The plant displayed mosaic symptoms and contained flexuous, filamentous virions of 700–750 × 10–11 nm typical of members of the genus Potyvirus. Infection of the sample by SCMV was confirmed by double antibody sandwich ELISA and RT-PCR amplification of the coat protein coding region of the viral genome. In a phylogenetic analysis, the buffalo grass isolate was sister to a clade of maize-infecting isolates of SCMV from eastern Africa and was 75.8% and 79.4% identical to the exemplar isolate of SCMV at nucleotide and amino acid levels, respectively
Bermuda grass latent virus in Australia: genome sequence, sequence variation, and new hosts
Bermuda grass latent virus (BGLV; genus Panicovirus) is identified for the first time in Australia and in only the second country after the USA. A full-length genome sequence was obtained, which has 97% nucleotide sequence identity to that of the species exemplar isolate. Surveys for BGLV, utilising a newly designed universal panicovirus RT-PCR assay for diagnosis, demonstrated widespread infection by this virus in a broad variety of Bermuda grass cultivars (Cynodon dactylon and C. dactylon Ă— C. transvaalensis) grown in both New South Wales and Queensland. The virus was also detected in Rhodes grass (Chloris gayana) and Kikuyu grass (Cenchrus clandestinus), which are both important pasture grasses in subtropical Australia, and the latter is also grown as turf. Furthermore, the Rhodes grass plant, which had strong mosaic symptoms, was also infected with sugarcane mosaic virus, warranting further investigations as to whether synergistic interactions occur between these two viruses
Thyroid disease is a favorable prognostic factor in achieving sustained virologic response in chronic hepatitis C undergoing combination therapy: A nested case control study
<p>Abstract</p> <p>Background</p> <p>Interferon-α in combination with ribavirin is the current gold standard for treatment of chronic hepatitis C. It is unknown if the development of autoimmune thyroid disease (TD) during treatment confers an improved chance of achieving sustained virologic response. The aim of this study is to assess the chance of achieving sustained virologic response (SVR) in patients who developed TD during treatment when compared with those who did not.</p> <p>Methods</p> <p>We performed a tertiary hospital-based retrospective nested case-control analysis of 19 patients treated for hepatitis C who developed thyroid disease, and 76 controls (matched for age, weight, gender, cirrhosis and aminotransferase levels) who did not develop TD during treatment. Multivariate logistic-regression models were used to compare cases and controls.</p> <p>Results</p> <p>The development of TD was associated with a high likelihood of achieving SVR (odds ratio, 6.0; 95% confidence interval, 1.5 to 24.6) for the pooled group containing all genotypes. The likelihood of achieving SVR was increased in individuals with genotype 1 HCV infection who developed TD (odds ratio, 5.2; 95% confidence interval, 1.2 to 22.3), and all genotype 3 patients who developed TD achieved SVR.</p> <p>Conclusions</p> <p>Development of TD during treatment for hepatitis C infection is associated with a significantly increased chance of achieving SVR. The pathophysiogical mechanisms for this observation remain to be determined.</p> <p>Trial Registration</p> <p><it>The Australian New Zealand Clinical Trials Registry (ANZCTR)</it>: <a href="http://www.anzctr.org.au/ACTRB12610000830099.aspx">ACTRB12610000830099</a></p
On the heating mix of ITER (invited paper)
This paper considers the heating mix of ITER for the two main scenarios. Presently, 73MWof absorbed power are foreseen in the mix 20/33/20 for ECH, NBI and ICH. Given a sufficient edge stability, Q = 10 the goal of scenario 2 can be reached with 40MW power irrespective of the heating method but depends sensitively inter alia on the H-mode pedestal temperature, the density profile shape and on the characteristics of impurity transport. ICH preferentially heats the ions and would contribute specifically with Q 0.5, and strong off-axis current drive (CD). The findings presented here are based on revised CD efficiencies γ for ECCD and a detailed benchmark of several CD codes. With ECCD alone, the goals of scenario 4 can hardly be reached. Efficient off-axisCDis only possible with NBI.With beams, inductive discharges with fni > 0.8 can be maintained for 3000 s. The conclusion of this study is that the present heating mix of ITER is appropriate. It provides the necessary actuators to induce in a flexible way the best possible scenarios. The development risks of NBI at 1MeV can be reduced by operation at 0.85MeV
Expression of ECM proteins fibulin-1 and -2 in acute and chronic liver disease and in cultured rat liver cells
Fibulin-2 has previously been considered as a marker to distinguish rat liver myofibroblasts from hepatic stellate cells. The function of other fibulins in acute or chronic liver damage has not yet been investigated. The aim of this study has been to evaluate the expression of fibulin-1 and -2 in models of rat liver injury and in human liver cirrhosis. Their cellular sources have also been investigated. In normal rat liver, fibulin-1 and -2 were both mainly present in the portal field. Fibulin-1-coding transcripts were detected in total RNA of normal rat liver, whereas fibulin-2 mRNA was only detected by sensitive, real-time quantitative polymerase chain reaction. In acute liver injury, the expression of fibulin-1 was significantly increased (17.23-fold after 48 h), whereas that of fibulin-2 was not modified. The expression of both fibulin-1 and -2 was increased in experimental rat liver cirrhosis (19.16- and 26.47-fold, respectively). At the cellular level, fibulin-1 was detectable in hepatocytes, “activated” hepatic stellate cells, and liver myofibroblasts (2.71-, 122.65-, and 469.48-fold over the expression in normal rat liver), whereas fibulin-2 was restricted to liver myofibroblasts and was regulated by transforming growth factor beta-1 (TGF-β1) in 2-day-old hepatocyte cultures and in liver myofibroblasts. Thus, fibulin-1 and -2 respond differentially to single and repeated damaging noxae, and their expression is differently present in liver cells. Expression of the fibulin-2 gene is regulated by TGF-β1 in liver myofibroblasts
Neuroimage
The thalamus is a central integration structure in the brain, receiving and distributing information among the cerebral cortex, subcortical structures, and the peripheral nervous system. Prior studies clearly show that the thalamus atrophies in cognitively unimpaired aging. However, the thalamus is comprised of multiple nuclei involved in a wide range of functions, and the age-related atrophy of individual thalamic nuclei remains unknown. Using a recently developed automated method of identifying thalamic nuclei (3T or 7T MRI with white-matter-nulled MPRAGE contrast and THOMAS segmentation) and a cross-sectional design, we evaluated the age-related atrophy rate for 10 thalamic nuclei (AV, CM, VA, VLA, VLP, VPL, pulvinar, LGN, MGN, MD) and an epithalamic nucleus (habenula). We also used T1-weighted images with the FreeSurfer SAMSEG segmentation method to identify and measure age-related atrophy for 11 extra-thalamic structures (cerebral cortex, cerebral white matter, cerebellar cortex, cerebellar white matter, amygdala, hippocampus, caudate, putamen, nucleus accumbens, pallidum, and lateral ventricle). In 198 cognitively unimpaired participants with ages spanning 20–88 years, we found that the whole thalamus atrophied at a rate of 0.45% per year, and that thalamic nuclei had widely varying age-related atrophy rates, ranging from 0.06% to 1.18% per year. A functional grouping analysis revealed that the thalamic nuclei involved in cognitive (AV, MD; 0.53% atrophy per year), visual (LGN, pulvinar; 0.62% atrophy per year), and auditory/vestibular (MGN; 0.64% atrophy per year) functions atrophied at significantly higher rates than those involved in motor (VA, VLA, VLP, and CM; 0.37% atrophy per year) and somatosensory (VPL; 0.32% atrophy per year) functions. A proximity-to-CSF analysis showed that the group of thalamic nuclei situated immediately adjacent to CSF atrophied at a significantly greater atrophy rate (0.59% atrophy per year) than that of the group of nuclei located farther from CSF (0.36% atrophy per year), supporting a growing hypothesis that CSF-mediated factors contribute to neurodegeneration. We did not find any significant hemispheric differences in these rates of change for thalamic nuclei. Only the CM thalamic nucleus showed a sex-specific difference in atrophy rates, atrophying at a greater rate in male versus female participants. Roughly half of the thalamic nuclei showed greater atrophy than all extra-thalamic structures examined (0% to 0.54% per year). These results show the value of white-matter-nulled MPRAGE imaging and THOMAS segmentation for measuring distinct thalamic nuclei and for characterizing the high and heterogeneous atrophy rates of the thalamus and its nuclei across the adult lifespan. Collectively, these methods and results advance our understanding of the role of thalamic substructures in neurocognitive and disease-related changes that occur with aging. © 2022Initiative d'excellence de l'Université de Bordeau
A Measurement of Semileptonic B Decays to Narrow Orbitally-Excited Charm Mesons
The decay chain b -> Bbar -> D^{**0} l nu X, D^{**0} -> D^{*+} pi^-, D^{*+}
-> D^0 pi^+, D^0 ->(Kpi or K3pi) is identified in a sample of 3.9 million
hadronic Z decays collected with the OPAL detector at LEP. The branching ratio
BR (b -> Bbar) x BR (Bbar -> D^0_1 l nu X) x BR (D^0_1 -> D^{*+} pi^-) is
measured to be (2.64 +- 0.79 (stat) +- 0.39 (syst)) X 10^-3 for the J^P = 1^+
(D^0_1) state. For decays into the J^P = 2^+ (D^{*0}_2) state, an upper limit
of 1.4 X 10^-3 is placed on the branching ratio at the 95% confidence level.Comment: 20 pages, 6 figure
Search for the Standard Model Higgs Boson with the OPAL Detector at LEP
This paper summarises the search for the Standard Model Higgs boson in e+e-
collisions at centre-of-mass energies up to 209 GeV performed by the OPAL
Collaboration at LEP. The consistency of the data with the background
hypothesis and various Higgs boson mass hypotheses is examined. No indication
of a signal is found in the data and a lower bound of 112.7GeV/C^2 is obtained
on the mass of the Standard Model Higgs boson at the 95% CL.Comment: 51 pages, 21 figure
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