Abstract
Although the precision to which we know the unpolarized parton distribution functions (PDFs) of the nucleon has improved over the years, there remain kinematic regions where more data are ...needed to constrain PDFs, such as the ratio of the sea quark distributions
d
¯
/
u
¯
near the valence region. Furthermore, different measurements appear to suggest different high-
x
behaviors of this ratio. The
W
cross-section ratio (
W
+/
W
−
) in
pp
collisions is sensitive to the unpolarized sea quark distributions at large
Q
2
, set by the W mass, and can be used to help constrain the
d
¯
/
u
¯
ratio. The STAR experiment at RHIC is well equipped to measure the leptonic decays of
W
bosons produced in
pp
collisions at center of mass energies of 500 and 510 GeV. These proceedings present recent
W
cross-section ratio results measured by STAR, including preliminary results from data collected in 2017, which double the statistics when combined with the published results based on data samples recorded in 2011-2013.
During the last decade, microsatellites (short tandem repeats or STRs) have been successfully used for animal genetic identification, traceability and paternity, although in recent year single ...nucleotide polymorphisms (SNPs) have been increasingly used for this purpose. An efficient SNP identification system requires a marker set with enough power to identify individuals and their parents. Genetic diagnostics generally include the analysis of related animals. In this work, the degree of information provided by SNPs for a consanguineous herd of cattle was compared with that provided by STRs. Thirty-six closely related Angus cattle were genotyped for 18 STRs and 116 SNPs. Cumulative SNPs exclusion power values (Q) for paternity and sample matching probability (MP) yielded values greater than 0.9998 and 4.32E(-42), respectively. Generally 2-3 SNPs per STR were needed to obtain an equivalent Q value. The MP showed that 24 SNPs were equivalent to the ISAG (International Society for Animal Genetics) minimal recommended set of 12 STRs (MP ∼ 10(-11)). These results provide valuable genetic data that support the consensus SNP panel for bovine genetic identification developed by the Parentage Recording Working Group of ICAR (International Committee for Animal Recording).
Double-spin asymmetries and absolute cross sections were measured at large Bjorken x (0.25 < or = x < or = 0.90), in both the deep-inelastic and resonance regions, by scattering longitudinally ...polarized electrons at beam energies of 4.7 and 5.9 GeV from a transversely and longitudinally polarized super(3)He target. In this dedicated experiment, the spin structure function g super(3He) sub(2) was determined with precision at large x, and the neutron twist-3 matrix element d super(n) sub(2)was measured at left angle bracketQ super(2)right angle bracket of 3.21 and 4.32 GeV super(2)/c super(2), with an absolute precision of about 10 super(-5). Our results are found to be in agreement with lattice QCD calculations and resolve the disagreement found with previous data at left angle bracketQ super(2)right angle bracket = 5 GeV super(2)/c super(2). Combining d super(n) sub(2)and a newly extracted twist-4 matrix element f super(n) sub(2) the average neutron color electric and magnetic forces were extracted and found to be of opposite sign and about 30 MeV in magnitude.
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With interest in large area GEM foils increasing and CERN being the only main distributor, keeping up with the demand for GEM foils will be difficult. Thus the commercialization of GEMs is being ...established by Tech-Etch of Plymouth, MA, USA using single-mask techniques. We report here on the first of a two step quality verification of the commercially produced 10×10cm2 and 40×40cm2 GEM foils, which includes characterizing their electrical and geometrical properties. We have found that the Tech-Etch foils display excellent electrical properties, as well as uniform and consistent hole diameters comparable to established foils produced by CERN.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
In bovines, there are significant differences within and among beef breeds in the time when bulls reach puberty. Although the timing of puberty is likely to be a multigenic trait, previous studies ...indicate that there may also be single genes that exert major effects on the timing of puberty within the general population. Despite its economic importance, there are not many SNPs or genetic markers associated with the age of puberty in male cattle. In the present work, we selected three candidate genes, GNRHR, LHR and IGF1, and associated their polymorphisms with the age of puberty in Angus male cattle.
After weaning, 276 Angus males were measured every month for weight (W), scrotal circumference (SC), sperm concentration (C) and percentage of motility (M). A total of 4 SNPs, two within GNRHR, one in LHR and one in IGF1 were genotyped using the pyrosequencing technique. IGF1-SnaBI SNP was significant associated (P < 0.01) with age at SC 28 cm, but it were not associated with age at M 10% and C 50 million. Genotype CC exhibited an average age at SC 28 cm of 7 and 11 days higher than CT (p = 0.037) and TT (p = 0.012), respectively. This SNP explained 1.5% of the genetic variance of age of puberty at SC28. LHR-I499L, GNRHR-SNP5 and GNRHR-SNP6 were not associated with any of the measurements. However, GNRHR haplotypes showed a suggestive association with age at SC 28 cm.
The findings presented here could support the hypothesis that IGF1 is a regulator of the arrival to puberty in male calves and is involved in the events that precede and initiate puberty in bull calves. Given that most studies in cattle, as well as in other mammals, were done in female, the present results are the first evidence of markers associated with age at puberty in male cattle.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Since the 1990s several authors have envisaged the use of DNA to certify meat origin. Two major parameters must be assessed before a DNA based traceability protocol can be implemented in the food ...chain: (i) the information content of a DNA marker set in a specific livestock breed or group of breeds; (ii) the minimum number of DNA markers needed to obtain a statistically acceptable match probability. The objective of the present work was to establish the effect of different levels of inbreeding in the matching efficiency, and the minimum number of microsatellite markers needed, in a DNA based meat traceability program, starting from an 11-microsatellite marker panel. Samples were obtained from beef production farms in South America, where animals are typically bred under pasture-based extensive conditions. Three groups of animals with different consanguinity rates were sampled. Exclusion power (
Q) was higher than 0.999998 and match probability lower than 3.01E−08, for the whole set of markers within each group. Both values were affected by consanguinity. To reach a two mismatch criteria exclusion power (
Q
2) of 99.99, six markers were needed in unrelated animals whereas seven markers were needed in related animals. To reach
Q
2
=
99.9999, 8 and 10 microsatellite markers, respectively, were needed. In general, one or two more microsatellite markers were needed to identify consanguineous animals. This study proved the DNA marker set used to be suitable for the identification of the meat from all slaughtered animals in Argentina, per week, month, and year.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
8.
A new Transition Radiation detector based on GEM technology Barbosa, F.; Fenker, H.; Furletov, S. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
10/2019, Volume:
942, Issue:
C
Journal Article
Peer reviewed
Open access
Transition Radiation Detectors (TRD) have the attractive feature of separating particles by their gamma factor. Classical TRDs are based on Multi-Wire Proportional Chambers (MWPC) or straw tubes, ...using a Xenon based gas mixture to efficiently absorb transition radiation photons. These detectors operate well in experiments with relatively low particle multiplicity. The performance of MWPC-TRD in experiments with luminosity of order 1034cm2s−1 and above, is significantly deteriorated due to the high particle multiplicity and channel occupancy. Replacing MWPC or straw tubes with a high granularity Micro Pattern Gas Detectors (MPGD) like Gas Electron Multipliers (GEMs), could improve the performance of the TRD. In addition, GEM technology allows one to combine a tracker with TRD identification (GEM-TRD/T). This report presents a new TRD development based on GEM technology for the future Electron Ion Collider (EIC). The first beam test was performed at Jefferson Lab (Hall-D) using 3–6 GeV electrons. A GEM-TRD/T module has been exposed to electrons with and without a fiber radiator. First results of test beam measurements and comparison with Geant4 Monte Carlo are presented in this article.
•New development of a transition radiation detector based on GEM technology.•The first results of beam test measurements and comparison with Geant4 Monte Carlo.•Neural network algorithms for extracting the electron/pion rejection power.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Canine chronic superficial keratitis (CSK) is an inflammatory corneal disease that primarily occurs in German shepherd dogs (GSDs). Several studies support the hypothesis that CSK is an ...immune-mediated disease. To investigate the genetic factors associated with CSK development, the upstream regulatory regions (URRs) of the DLA-DRB, -DQA and -DQB genes were genotyped in 60 dogs, including 32 CSK animals. LD analysis identified two blocks (r2≤45), with two DLA-DRB1 and five DLA-DQB1 haplotypes. Analysis of DLA-URR alleles/haplotypes showed a significant association between DQB1*-154 C/T (p=0.016) and CSK, suggesting that the T variant may increase the risk for developing CSK disease (OR=3, 95% CI=1.25–7.68). When haplotype associations were performed, the URR-DQB*CATT haplotype was significantly associated with CSK (p=0.016), increasing the risk of develop this disease over two-fold (OR=3, 95%, CI=1.25–7.68). These results showed that dogs homozygous at DRB1*69 C/T had a risk for developing CSK disease that was over four times the risk for heterozygotes. This genetic association supports the previous clinical, histological and pharmacological studies that suggest that CSK is an immune-mediated disease, and this association could potentially be used to identify susceptible animals.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
We report on the results of the E06-014 experiment performed at Jefferson Lab in Hall A, where a precision measurement of the twist-3 matrix element d2 of the neutron (d2n) was conducted. The ...quantity d2n represents the average color Lorentz force a struck quark experiences in a deep inelastic electron scattering event off a neutron due to its interaction with the hadronizing remnants. This color force was determined from a linear combination of the third moments of the He3 spin structure functions, g1 and g2, after nuclear corrections had been applied to these moments. The structure functions were obtained from a measurement of the unpolarized cross section and of double-spin asymmetries in the scattering of a longitudinally polarized electron beam from a transversely and a longitudinally polarized He3 target. The measurement kinematics included two average Q2 bins of 3.2 GeV2 and 4.3 GeV2, and Bjorken-x 0.25≤x≤0.90 covering the deep inelastic and resonance regions. We have found that d2n is small and negative for ⟨Q2⟩=3.2 GeV2, and even smaller for ⟨Q2⟩=4.3 GeV2, consistent with the results of a lattice QCD calculation. The twist-4 matrix element f2n was extracted by combining our measured d2n with the world data on the first moment in x of g1n, Γ1n. We found f2n to be roughly an order of magnitude larger than d2n. Utilizing the extracted d2n and f2n data, we separated the Lorentz color force into its electric and magnetic components, FEy,n and FBy,n, and found them to be equal and opposite in magnitude, in agreement with the predictions from an instanton model but not with those from QCD sum rules. Furthermore, using the measured double-spin asymmetries, we have extracted the virtual photon-nucleon asymmetry on the neutron A1n, the structure function ratio g1n/F1n, and the quark ratios (Δu+Δu¯)/(u+u¯) and (Δd+Δd¯)/(d+d¯). These results were found to be consistent with deep-inelastic scattering world data and with the prediction of the constituent quark model but at odds with the perturbative quantum chromodynamics predictions at large x.
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