3,971 research outputs found
EVALUATING A PRECISION AGRICULTURE HERBICIDE DECISION MODEL FOR WINTER WHEAT
Replaced with revised version of paper 08/02.Crop Production/Industries,
Study of the Top-quark Pair Production in Association with a Bottom-quark Pair from Fast Simulations at the LHC
A large number of top quarks will be produced at the Large Hadron Collider
(LHC) for Run II period. This will allow us to measure the rare processes from
the top sector in great details. We present the study of the top-quark pair
production in association with a bottom-quark pair (ttbb) from fast simulations
for the Compact Muon Solenoid (CMS) experiment. The differential distributions
of ttbb are compared with the top-quark pair production with two additional
jets (ttjj) and with the production in association with the Higgs (ttH), where
the Higgs decays to a bottom-quark pair. The significances of ttbb process in
the dileptonic and semileptonic decay mode are calculated with the data
corresponding to an integrated luminosity of 10 fb-1, which is foreseen to be
collected in the early Run II period. This study will be an important input in
searching for new physics beyond the standard model as well as in searching for
ttH process where the Yukawa coupling with the top quark can be directly
measured.Comment: 12 pages, 12 figure
BIOMECHANICAL ANALYSIS A SEQENCE OF ANGULAR VELOCITY AND COORDINATED MUSCLES ACTIVITY DURING BASEBALL HITTING
The purpose of this study was to analyse a sequence of rotations and coordinated muscles activities of upper body. Using kinematic and EMG data from 3 recreational university baseball players participating in this study, we computed the angular velocity of trunk, pelvis, bat and trunk-pelvis rotation angle and PMT of upper body muscles. Trunkpelvis rotation angle was 22 ° before the bat-ball contact. The pelvis, trunk, and bat showed a sequence of angular velocity beginning with the hip, followed by the trunk, and end tip of the bat. Additionally, PMT of upper body muscles generated right pectoralis major(1.03 sec.), right external oblique(1.11 sec.), left thoracloumbar fasci(1.12 sec.), left external oblique(1.13 sec.), right latissimus dorsi(1.15 sec.), left latissimus dorsi(1.16 sec.), right thoracloumbar fascia(1.16 sec.), left pectoralis major(1.25 sec.), on at a time during baseball hitting motion. PMT of upper body muscles were related to the shifting and rotating of body segment and this action can be considered the coordinated muscle activities of upper body
Alpha-tocopherol exerts protective function against the mucotoxicity of particulate matter in amphibian and human goblet cells
Exposure to particulate matter (PM) in ambient air is known to increase the risk of cardiovascular disorders and mortality. The cytotoxicity of PM is mainly due to the abnormal increase of reactive oxygen species (ROS), which damage cellular components such as DNA, RNA, and proteins. The correlation between PM exposure and human disorders, including mortality, is based on long-term exposure. In this study we have investigated acute responses of mucus-secreting goblet cells upon exposure to PM derived from a heavy diesel engine. To this end, we employed the mucociliary epithelium of amphibian embryos and human Calu-3 cells to examine PM mucotoxicity. Our data suggest that acute exposure to PM significantly impairs mucus secretion and results in the accumulation of mucus vesicles in the cytoplasm of goblet cells. RNA-seq analysis revealed that acute responses to PM exposure significantly altered gene expression patterns; however, known regulators of mucus production and the secretory pathway were not significantly altered. Interestingly, pretreatment with alpha-tocopherol nearly recovered the hyposecretion of mucus from both amphibian and human goblet cells. We believe this study demonstrates the mucotoxicity of PM and the protective function of alpha-tocopherol on mucotoxicity caused by acute PM exposure from heavy diesel engines
Carotid Endarterectomy for Symptomatic Complete Occlusion of the Internal Carotid Artery
We described 9 consecutive patients who underwent operative carotid artery exploration with attempted carotid endarterectomy (CEA) for symptomatic internal carotid artery (ICA) occlusion. Indications for this surgery based on vascular imaging included segmental occlusion of the proximal ICA and also extensive occlusion of the distal ICA in selected patients in whom color-flow duplex ultrasound showed a poorly echogenic or anechoic thrombus with a flow void, suggestive of an acute thrombus. CEA was performed successfully to restore blood flow in all 9 patients:CEA in 5 and CEA with Fogarty thrombectomy in 4. Postoperative magnetic resonance (MR) angiography confirmed that revascularization had been successful in all 9 patients, and MR imaging displayed improved perfusion in 4 patients. Despite the lack of a generalized efficacy of surgical revascularization for symptomatic ICA occlusion, our study demonstrated that preoperative vascular imaging allows the selection of patients who may benefit from CEA
High Temperature Deformation Behavior of 8090 Al-Li Alloy
High temperature deformation behavior, especially the superplasticity of an 8090 Al-Li alloy, was studied within the recent framework of the internal variable theory of structural superplasticity. In this study, a series of load relaxation tests were conducted at various temperatures ranging from 200°C to 530°C to obtain the flow curves of logâÎ”Ë versus logâΔ. The effect of grain size was also examined by varying the grain sizes through a proper thermomechanical treatment. The flow curves were found to be composite curves consisting of contributions from grain boundary sliding (GBS) and grain matrix deformation (GMD) at superplastic temperatures. The activation energy obtained for GMD was 124.9âkJ/mole in the temperature range from 470°C to 530°C, very similar to that for self-diffusion in pure Al
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