2,771 research outputs found
Predicative Ability of QCD Sum Rules for Decuplet Baryons
QCD sum rules for decuplet baryon two-point functions are investigated using
a comprehensive Monte-Carlo based procedure. In this procedure, all
uncertainties in the QCD input parameters are incorporated simultaneously,
resulting in realistic estimates of the uncertainties in the extracted
phenomenological parameters. Correlations between the QCD input parameters and
the phenomenological parameters are studied by way of scatter plots. The
predicted couplings are useful in evaluating matrix elements of decuplet
baryons in the QCD sum rule approach. They are also used to check a cubic
scaling law between baryon couplings and masses, as recently found by Dey and
coworkers. The results show a significant reduction in the scaling constant and
some possible deviations from the cubic law.Comment: 13 pages, RevTeX, 5 PS figures embedded with psfig.st
Transport Activity of Rice Sucrose Transporters OsSUT1 and OsSUT5
Expression in Xenopus oocytes and electrophysiology was used to test for transport activity of the five sucrose transporter (SUT) homologs from rice. Expression of OsSUT1 and OsSUT5 resulted in sucrose-dependent currents that were analyzed by two-electrode voltage clamping. We examined the transport kinetics, substrate specificity and pH dependence of sucrose transport and K0.5 for sucrose. OsSUT1 showed similar features to those of other type II SUTs from monocots examined previously, with a K0.5 value of 7.50 mM at pH 5.6. In contrast, OsSUT5 had a higher substrate affinity (K0.5 = 2.32 mM at pH 5.6), less substrate specificity and less pH dependence compared with all type II SUTs tested to date. Regulation of the rice SUTs, as well as ZmSUT1 from maize and HvSUT1 from barley, by reduced (GSH) and oxidized (GSSG) forms of glutathione was tested. GSSG and GSH were found to have no significant effect on the activity of sucrose transporters when expressed in Xenopus oocytes. In conclusion, differences in transport activity between OsSUT1 and OsSUT5 indicate that type II SUTs have a range of transport activities that are tuned to their function in the plant
Predictive Ability of QCD Sum Rules for Excited Baryons
The masses of octet baryons are calculated by the method of QCD sum rules.
Using generalized interpolating fields, three independent sets of QCD sum rules
are derived which allow the extraction of low-lying N* states with spin-parity
1/2+, 1/2- and 3/2- in both the non-strange and strange channels. The
predictive ability of the sum rules is examined by a Monte-Carlo based analysis
procedure in which the three phenomenological parameters (mass, coupling,
threshold) are treated as free parameters simultaneously. Realistic
uncertainties in these parameters are obtained by simultaneously exploring all
uncertainties in the QCD input parameters. Those sum rules with good predictive
power are identified and their predictions are compared with experiment where
available.Comment: 33 pages, 2 figure
Market forces and competition are not necessarily detrimental to sustainability
Paul T.M. Ingenbleek and Machiel J. Reinders study the case of coffee roasters and supermarkets in the Netherland
Reduced susceptibility of western corn rootworm (\u3ci\u3eDiabrotica virgifera virgifera\u3c/i\u3e LeConte) populations to Cry34/35Ab1‑expressing maize in northeast Nebraska
The western corn rootworm (WCR; Diabrotica virgifera virgifera LeConte) is a significant pest of maize (Zea mays L.) across the United States Corn Belt. Transgenic maize hybrids expressing insecticidal proteins derived from Bacillus thuringiensis (Bt) have been used to manage WCR since 2003. Widespread resistance to Cry3Bb1 (and associated cross-resistance to mCry3A and eCry3.1Ab) has placed increased selection pressure on Cry34/35Ab1 in single-protein and pyramided transgenic maize hybrids. Data on the susceptibility of Nebraska WCR populations to Cry34/35Ab1 has not been published since 2015 and plant-based bioassays conducted in 2017–2018 confirmed resistance to Cry3Bb1 + Cry34/35Ab1 maize, suggesting resistance to Cry34/35Ab1 has evolved in the Nebraska landscape. Therefore, plant-based bioassays were conducted on F1 progeny of WCR populations collected from northeast Nebraska in 2018 and 2019. Larval survival and development were used to classify resistance to Cry34/35Ab1 in each WCR population. Bioassays confirmed incomplete resistance to Cry34/35Ab1 maize in 21 of 30 WCR populations; 9 of 30 WCR populations remained susceptible to Cry34/35Ab1. Collectively, results indicate that northeast Nebraska WCR populations were in the initial stages of resistance evolution to Cry34/35Ab1 during 2018–2019. Appropriate resistance management strategies are needed to mitigate resistance and preserve efficacy of rootworm-active products containing Cry34/35Ab1
Real-time irradiance simulation for PV products and building integrated PV in a virtual reality environment
Evidence of western corn rootworm (\u3ci\u3eDiabrotica virgifera virgifera\u3c/i\u3e LeConte) field-evolved resistance to Cry3Bb1 + Cry34/ 35Ab1 maize in Nebraska
BACKGROUND: Western corn rootworm (WCR; Diabrotica virgifera virgifera) field-evolved resistance to transgenic maize expressing the Cry3Bb1 protein derived from Bacillus thuringiensis (Bt) has been confirmed across the United States Corn Belt. Although use of pyramided hybrids expressing Cry3Bb1 + Cry34/35Ab1 has increased in recent years to mitigate existing WCR Bt resistance, susceptibility of Nebraska WCR populations to this rootworm–Bt pyramid has not been assessed. Plant-based bioassays were used to characterize the susceptibility of WCR populations to Cry3Bb1 and Cry3Bb1 + Cry34/35Ab1 maize. Populations were collected from areas of northeastern Nebraska with a history of planting Bt maize that expressed Cry3Bb1 and Cry34/35Ab1.
RESULTS: Significant differences in mean corrected survival among populations within Bt hybrids indicated a mosaic of WCR susceptibility to Cry3Bb1 + Cry34/35Ab1 and Cry3Bb1 maize occurred in the landscape. All field populations exhibited some level of resistance to one or both Bt hybrids when compared to susceptible laboratory control populations in bioassays. Most WCR populations exhibited incomplete resistance to Cry3Bb1 + Cry34/35Ab1 maize (92%) and complete resistance to Cry3Bb1 maize (79%).
CONCLUSION: The present study confirms the first cases of field-evolved resistance to Cry3Bb1 + Cry34/35Ab1 maize in Nebraska and documents a landscape-wide WCR Cry3Bb1 resistance pattern in areas characterized by long-term continuous maize production and associated planting of Cry3Bb1 hybrids. Use of a multi-tactic integrated pest management approach is needed in areas of continuous maize production to slow or mitigate resistance evolution to Bt maize
Positive and negative-parity flavor-octet baryons in coupled QCD sum rules
We apply the method of the QCD sum rule, in which positive- and
negative-parity baryons couple with each other, to the flavor-octet hyperons
and investigate the parity splittings. We also reexamine the nucleon in the
method, which was studied in our previous paper, by carefully choosing the
Borel weight. Both in the nucleon and hyperon channels the obtained sum rules
turn out to have a very good Borel stability and also have a Borel window, an
energy region in which the OPE converges and the pole contribution dominates
over the continuum contribution. The predicted masses of the positive- and
negative-parity baryons reproduce the experimental ones fairly well in the
and channels, if we assign the and the
to the parity partners of the and the ,
respectively. This implies that the is not the party partner of
the and may be a flavor-singlet or exotic state. In the
channel, the sum rule predicts the mass of the negative-parity state to be
about 1.8 GeV, which leads to two possibilities; one is that the observed state
with the closest mass, , is the parity partner and the other is that
the parity partner is not yet found but exists around 1.8 GeV.Comment: 15 pages, 4 figure
Blocked All-Pairs Shortest Paths Algorithm on Intel Xeon Phi KNL Processor: A Case Study
Manycores are consolidating in HPC community as a way of improving
performance while keeping power efficiency. Knights Landing is the recently
released second generation of Intel Xeon Phi architecture. While optimizing
applications on CPUs, GPUs and first Xeon Phi's has been largely studied in the
last years, the new features in Knights Landing processors require the revision
of programming and optimization techniques for these devices. In this work, we
selected the Floyd-Warshall algorithm as a representative case study of graph
and memory-bound applications. Starting from the default serial version, we
show how data, thread and compiler level optimizations help the parallel
implementation to reach 338 GFLOPS.Comment: Computer Science - CACIC 2017. Springer Communications in Computer
and Information Science, vol 79
Eta-nucleon coupling constant in QCD with SU(3) symmetry breaking
We study the NN coupling constant using the method of QCD sum rules
starting from the vacuum-to-eta correlation function of the interpolating
fields of two nucleons. The matrix element of this correlation has been taken
with respect to nucleon spinors to avoid unwanted pole contribution. The
SU(3)-flavor symmetry breaking effects have been accounted for via the
-mass, s-quark mass and eta decay constant to leading order. Out of the
four sum rules obtained by taking the ratios of the two sum rules in
conjunction with the two sum rules in nucleon mass, three are found to give
mutually consistent results. We find the SU(3) breaking effects significant, as
large as 50% of the SU(3) symmetric part.Comment: 13 pages, 12 figure
- …