3,556 research outputs found
{Twisted Poincar\'e Series and Geometric Factorization of Affine Weyl Groups
We study the relation between the alternating product of twisted Poincar'e
series of parabolic subgroups of affine Weyl groups and hyperbolic stabilizers
of geodesic tubes. Moreover, from such relation, we find a length-preserving
factorization of affine Weyl groups of type and
The effect of anterior surgery for the patients with thoraclumbar-segment bursting fracture
目的 评价经前路手术治疗脊柱胸腰段爆裂性骨折的疗效。方法 对18例脊柱胸腰段爆裂性骨折的患者行前路手术治疗,手术后做6~48个月(平均14.6个月)的随访研究。结果 所有病例达到植骨融合,脊柱的高度、生理弧度恢复并保持较好,内固定无松动、断裂,除1例神经功能分级为A的患者神经功能没有明显恢复外,其他病例的神经功能都有1~3级的恢复。没有发生严重并发症的病例。结论 前路减压、植骨、内固定治疗脊柱胸腰段爆裂性骨折能彻底减压,充分植骨,稳定脊柱,有较好疗效。Obsjective: To evaluate the effect of anterior surgery for the patients with thoraclumbar-segment bursting fracture. Methods: 13 patients with thoraclumbar-segment burstingfracture were treated through anterior surgery. After operation, the patients were followed-up for 6-24 months (average 15 months).According to Frankel’s grading of preoperation neurological lesions, 1 case was classified into A grade, 4cases into B grade, 8 cases into C grade, 4 cases into D grade, 1cases into Egrade. Results: All of the interbody autogenous strut graftings achieved solid fusion. The height and physiologic curve of vertebral column for all of the cases were recovered and maitained very well. Loosening and breaking for the internal fixations did not been found. Excepting the case of Frankel’s grade A, others achieved 1-3 grade recovering for nerve function. No serious complications were found. Conclusion: The treatment from anterior surgery for the patients with thoraclumbar-segment bursting fracture could achieve thorough decompressing, sufficient grafting-bone fusioning, stabling vertebral column and satisfactory outcome
Effect of ω-3 Fatty Acid on Gastrointestinal Motility after Abdominal Operation in Rats
Objective. To investigate whether ω-3 fatty acid could stimulate gastrointestinal motility after abdominal operation. Method. Wistar rats were randomly divided into 3 group (normal saline group, intralipid group, and ω-3 fatty acid group, n = 18/group) after partial caecectomy and gastrostomosis, each group was divided into 3 groups (POD1, POD3, and POD6, n = 6/group). Serum gastrin (GAS), motilin (MTL), interleukin-1 (IL-1), interleukin-6 (IL-6), tissue necrosis factor-α (TNF-α), cyclooxygenase-2 (COX-2), gastric emptying rate, and small bowel propulsion rate were measured. Results. On POD 3, gastric emptying rate and small bowel propulsion rate in ω-3 fatty acid group were higher than those in normal saline group and intralipid group. Serum GAS and MTL levels in ω-3 fatty acid group were higher than those in normal saline group, but serum IL-1, IL-6, TNF-α, and COX-2 levels were lower than those in normal saline group and intralipid group. Conclusion. ω-3 fatty acid could accelerate the recovery of gastrointestinal mobility after abdominal operation in rats, mainly by relieving postoperative inflammation
Shedding New Light on and from Semileptonic Decays
We compute for the first time the next-to-leading-order QCD corrections to
the form factors at large hadronic recoil.
Both the charm-quark-mass and the strange-quark-mass dependent pieces can
generate the leading-power contributions to these form factors. Including
further various power-suppressed contributions, we perform the combined fits of
the considered form factors to both our large-recoil theory predictions and the
lattice QCD results, thus improving upon the previous determinations of the
lepton-flavour-universality ratios significantly.Comment: 6 pages plus Supplemental Material, 3 figures, 1 table, 2 ancillary
file
Precision calculations of decay form factors in soft-collinear effective theory
We improve QCD calculations of the form factors at
large hadronic recoil by implementing the next-to-leading-logarithmic
resummation for the obtained leading-power light-cone sum rules in the
soft-collinear effective theory (SCET) framework. Additionally, we endeavour to
investigate a variety of the subleading-power contributions to these
heavy-to-light form factors at , by including the
higher-order terms in the heavy-quark expansion of the hard-collinear quark
propagator, by evaluating the desired effective matrix element of the
next-to-leading-order term in the representation of the weak
transition current, by taking into account the off-light-cone contributions of
the two-body heavy-quark effective theory matrix elements as well as the
three-particle higher-twist corrections from the subleading bottom-meson
light-cone distribution amplitudes, and by computing the twist-five and
twist-six four-body higher-twist effects with the aid of the factorization
approximation. Having at our disposal the SCET sum rules for the exclusive
-meson decay form factors, we further explore in detail numerical
implications of the newly computed subleading-power corrections by employing
the three-parameter model for both the leading-twist and higher-twist -meson
distribution amplitudes. Taking advantage of the customary
Bourrely-Caprini-Lellouch parametrization for the semileptonic form factors, we then determine the correlated numerical results for
the interesting series coefficients, by carrying out the simultaneous fit of
the exclusive -meson decay form factors to both the achieved SCET sum rule
predictions and the available lattice QCD results.Comment: 74 pages, 15 figure
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