We have measured parity-violating asymmetries in elastic electron-proton scattering over the range of momentum transfers 0.12 < or =Q2 < or =1.0 GeV2. These asymmetries, arising from interference of ...the electromagnetic and neutral weak interactions, are sensitive to strange-quark contributions to the currents of the proton. The measurements were made at Jefferson Laboratory using a toroidal spectrometer to detect the recoiling protons from a liquid hydrogen target. The results indicate nonzero, Q2 dependent, strange-quark contributions and provide new information beyond that obtained in previous experiments.
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Recent developments in Geant4 Allison, J.; Amako, K.; Apostolakis, J. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
11/2016, Volume:
835, Issue:
C
Journal Article
Peer reviewed
Open access
Geant4 is a software toolkit for the simulation of the passage of particles through matter. It is used by a large number of experiments and projects in a variety of application domains, including ...high energy physics, astrophysics and space science, medical physics and radiation protection. Over the past several years, major changes have been made to the toolkit in order to accommodate the needs of these user communities, and to efficiently exploit the growth of computing power made available by advances in technology. The adaptation of Geant4 to multithreading, advances in physics, detector modeling and visualization, extensions to the toolkit, including biasing and reverse Monte Carlo, and tools for physics and release validation are discussed here.
•Multithreading resulted in a smaller memory footprint and nearly linear speed-up.•Scoring options, faster geometry primitives, more versatile visualization were added.•Improved electromagnetic and hadronic models and cross sections were developed.•Reverse Monte Carlo and general biasing methods were added.•Physics validation efforts were expanded and new validation tools were added.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Neurocognitive impairments in euthymic patients with bipolar disorder may represent trait rather than state variables.
To test the hypothesis that euthymic patients with bipolar disorder would ...exhibit impairment in verbal learning and memory and executive function compared with healthy controls matched for age, gender and premorbid IQ.
Twenty euthymic patients with bipolar disorder were matched, on a case-by-case basis, to twenty healthy community controls. Cases and controls were tested with a battery of neuropsychological tests.
Impairments were found in cases compared with controls in tests of verbal learning and memory. Verbal learning and memory correlated negatively with the number of manic episodes.
Impaired verbal learning and memory may be a trait variable in bipolar disease. There are implications for adherence to medication and relapse and for the role of early treatment interventions. Prospective designs and targeting first-episode groups may help to differentiate trait v. disease process effects.
Primary bovine mammary epithelial cells (pbMEC) are often used in cell culture to study metabolic and inflammatory processes in the udder of dairy cows. The most common source is udder tissue from ...biopsy or after slaughter. However, it is also possible to culture them from milk, which is non-invasive, repeatable and yields less contamination with fibroblasts. Generally, not much is known about the influence of cell origin and cell culture techniques such as cryopreservation on pbMEC functionality. Cells were extracted from milk and udder tissue to evaluate if milk-derived pbMEC are a suitable alternative to tissue-derived pbMEC and to test what influence cryopreservation has. The cells were cultivated for three passages and stored in liquid nitrogen. The relative gene expression of the five target genes kappa-casein, lingual antimicrobial peptide (LAP), lactoferrin, lysozyme (LYZ1) and the prolactin receptor normalised with keratin 8 showed a tendency to decrease in the tissue cultures, but not in the milk-derived cultures, suggesting a greater influence of the cultivation process on tissue-derived cells, freezing lowered expression levels in both cultures. Overall expression of LAP and LYZ1 tended to be higher in milk cells. Cholesterol efflux was measured to compare passages one to seven in milk-derived cells. Passage number did not alter the efflux rate (p ≤ 0.05). We showed for the first time that the extraction of pbMEC from milk can be a suitable alternative to tissue extraction.
To gain further insight into the mechanisms underlying muscle insulin resistance, the influence of obesity and type 2 diabetes on GLUT4 immunoreactivity in slow and fast skeletal muscle fibers was ...studied. Through a newly developed, very sensitive method using immunohistochemistry combined with morphometry, GLUT4 density was found to be significantly higher in slow compared with fast fibers in biopsy specimens from lean and obese subjects. In contrast, in type 2 diabetic subjects, GLUT4 density was significantly lower in slow compared with fast fibers. GLUT4 density in slow fibers from diabetic patients was reduced by 9% compared with the weight-matched obese subjects and by 18% compared with the lean control group. The slow-fiber fraction was reduced to 86% in the obese subjects and to 75% in the diabetic subjects compared with the control group. Estimated GLUT4 contribution from slow fibers was reduced to 77% in the obese subjects and to 61% in type 2 diabetic patients compared with the control subjects. We propose that a reduction in the fraction of slow-twitch fibers, combined with a reduction in GLUT4 expression in slow fibers, may reduce the insulin-sensitive GLUT4 pool in type 2 diabetes and thus contribute to skeletal muscle insulin resistance.
To evaluate the clinical characteristics of the 3 classifications of vitreous seeds in retinoblastoma-dust (class 1), spheres (class 2), and clouds (class 3)-and their responses to intravitreal ...melphalan.
Retrospective, bi-institutional cohort study.
A total of 87 patient eyes received 475 intravitreal injections of melphalan (median dose, 30 μg) given weekly, a median of 5 times (range, 1-12 times).
At presentation, the vitreous seeds were classified into 3 groups: dust, spheres, and clouds. Indirect ophthalmoscopy, fundus photography, ultrasonography, and ultrasonic biomicroscopy were used to evaluate clinical response to weekly intravitreal melphalan injections and time to regression of vitreous seeds. Kaplan-Meier estimates of time to regression and ocular survival, patient survival, and event-free survival (EFS) were calculated and then compared using the Mantel-Cox test of curve.
Time to regression of vitreous seeds, patient survival, ocular survival, and EFS.
The difference in time to regression was significantly different for the 3 seed classes (P < 0.0001): the median time to regression was 0.6, 1.7, and 7.7 months for dust, spheres, and clouds, respectively. Eyes with dust received significantly fewer injections and a lower median and cumulative dose of melphalan, whereas eyes with clouds received significantly more injections and a higher median and cumulative dose of melphalan. Overall, the 2-year Kaplan-Meier estimates for ocular survival, patient survival, and EFS (related to target seeds) were 90.4% (95% confidence interval CI, 79.7-95.6), 100%, and 98.5% (95% CI, 90-99.7), respectively.
The regression and response of vitreous seeds to intravitreal melphalan are different for each seed classification. The vitreous seed classification can be predictive of time to regression, number, median dose, and cumulative dose of intravitreal melphalan injections required.
Herbage minerals affect performance of grazing cattle. We investigated the response of herbage P, K, Ca and Mg contents and Ca/P and K/(Ca + Mg) ratios to long‐term stocking rate, continuous vs. ...discontinued grazing practice, and sampling year. Cattle had been stocked at 2·4 and 4·8 animal unit months ha−1 since 1949. Exclosures were installed in April 1998. Herbage samples were collected near peak herbage mass in 2001, 2003, 2008 and 2012 and analysed for mineral content. Mineral contents were similar between the two stocking rates, but were lower (P < 0·05) under discontinued than continuous stocking, with the exception of similar P contents. The content of P and K in herbage was higher and the content of Ca and Mg was lower (P < 0·05) in years with greater precipitation and lower temperatures. Herbage mineral content, with the exception of P, exceeded minimum recommended levels for cattle. Given the low P content in herbage (0·74–1·19 g kg−1) and high Ca/P ratios during the dry and hot year (of 2001), a dietary P supplement should be considered for cattle grazing rough fescue grassland in drought years. The low K/(Ca + Mg) ratios (<2·2) suggest there is little risk of grass tetany in cattle grazing on this grassland.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
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