1,603 research outputs found
Evaluating Feynman integrals by the hypergeometry
The hypergeometric function method naturally provides the analytic
expressions of scalar integrals from concerned Feynman diagrams in some
connected regions of independent kinematic variables, also presents the systems
of homogeneous linear partial differential equations satisfied by the
corresponding scalar integrals. Taking examples of the one-loop and
massless functions, as well as the scalar integrals of two-loop vacuum
and sunset diagrams, we verify our expressions coinciding with the well-known
results of literatures. Based on the multiple hypergeometric functions of
independent kinematic variables, the systems of homogeneous linear partial
differential equations satisfied by the mentioned scalar integrals are
established. Using the calculus of variations, one recognizes the system of
linear partial differential equations as stationary conditions of a functional
under some given restrictions, which is the cornerstone to perform the
continuation of the scalar integrals to whole kinematic domains numerically
with the finite element methods. In principle this method can be used to
evaluate the scalar integrals of any Feynman diagrams.Comment: 39 pages, including 2 ps figure
贴片式动态心电记录仪在临床教学中可行性研究
Objective: To explore effectiveness of clinical application of the patch type dynamic ecg recorder by comparing with conventional dynamic ecg recorder Holter. And the clinical ecg teaching models is discussed in this paper. Methods: Using parallel controlled trial method, 60 patients in two hospitals received Holter examination, and patch heart testing at the same time. A comparative analysis of two kinds of inspection methods on testing the average heart rate, supraventricular premature beats and ventricular premature beat was made. Results: The average heart rate of patch type ECG and Holter were 71.87±9.28 and 72.55±9.06 (P = 0.0879). Two kinds of detection methods, chamber on the coincidence rate of premature beat (PPS) was 98.33%, 95% CI (91.06, 99.96), Kappa = 0.9462, 95% CI (0.84, 1.00), good consistency. The accuracy of ventricular premature beat (PPS) was 98.33%, 95% CI (91.06, 99.63), Kappa = 0.9850, 95% CI (0.90, 1.00), good consistency. Patch type heart all platform is suitable for self-study and clinical care study, and professional skill assessment,etc.Conclusion: The effectiveness of patch type heart all on testing the average heart rate, supraventricular premature beat is the same as Holter. it is also suitable for to carry out clinical ECG teaching at the same time.目的 通过和常规动态心电记录仪 Holter比较,研究贴片式的动态心电记录仪临床应用的有效性。并探讨其在临床心电教学中的模式。方法 采用自身平行对照试验方法,在两医院60例患者用Holter检查时,同时用贴片心电仪检测,比较分析两种检查方法在检测平均心率、室上性早搏和室性早搏方面的情况。结果 贴片式心电仪和Holter的平均心率分别为71.87±9.28和72.55±9.06(P=0.0879)。两种检测方法,室上性早搏的符合率(PPS)为 98.33%,95%CI为(91.06,99.96),Kappa=0.9462, 95%CI为(0.84,1.00),一致性良好。室性早搏的符合率(PPS)为 98.33%,95%CI为(91.06,99.63),Kappa=0.9850, 95%CI为(0.90, 1.00)。贴片式心电仪平台适合自学、临床监护学习、大课和专业技能考核等临床心电教学。结论 贴片式心电仪在检测平均心率、室上性早搏和室性早搏方面的有效性和Holter相同。同时也适合以此平台开展临床心电教学
O-GlcNAcylation in ischemic diseases
Protein glycosylation is an extensively studied field, with the most studied forms being oxygen or nitrogen-linked N-acetylglucosamine (O-GlcNAc or N-GlcNAc) glycosylation. Particular residues on proteins are targeted by O-GlcNAcylation, which is among the most intricate post-translational modifications. Significantly contributing to an organism’s proteome, it influences numerous factors affecting protein stability, function, and subcellular localization. It also modifies the cellular function of target proteins that have crucial responsibilities in controlling pathways related to the central nervous system, cardiovascular homeostasis, and other organ functions. Under conditions of acute stress, changes in the levels of O-GlcNAcylation of these proteins may have a defensive function. Nevertheless, deviant O-GlcNAcylation nullifies this safeguard and stimulates the advancement of several ailments, the prognosis of which relies on the cellular milieu. Hence, this review provides a concise overview of the function and comprehension of O-GlcNAcylation in ischemia diseases, aiming to facilitate the discovery of new therapeutic targets for efficient treatment, particularly in patients with diabetes
Research progress on rapid determination of edible vegetable oil components
This paper summarizes the rapid detection methods of edible vegetable oil components from the aspects of analysis principle and application technology, such as simulation sensory analysis, spectral analysis, electromagnetic spectrum analysis and biochip technology. The application results of these techniques in the component mixing identification of edible vegetable were further analyzed. It was showed that the integrated online rapid detection technology of multi-channel, multi parameter and multi capacity will be the developing direction of component analysis of edible vegetable oil and will lay a technical foundation for further improving the quality supervision of edible vegetable oil and safeguarding the interests of consumers in China
Different cerebral plasticity of intrinsic and extrinsic hand muscles after peripheral neurotization in a patient with brachial plexus injury: A TMS and fMRI study
AbstractContralateral C7 (CC7) neurotization has been an important approach for brachial plexus injury (BPI). Patients can achieve relatively good grasping function driven by the proximal extrinsic hand muscle (flexor digitorum, FD) after CC7 neurotization, whereas the thumb opposition function driven by the distal intrinsic muscle (abductor pollicis brevis, APB) is poor. The present study aimed to investigate the brain reorganization patterns of the recovery processes of intrinsic and extrinsic hand functions after repairing the median nerve by CC7 neurotization. Transcranial magnetic stimulation (TMS) and functional magnetic resonance imaging (fMRI) were used to evaluate the cerebral plasticity in one BPI patient after CC7 neurotization. After the CC7 neurotization, the patient showed improvements in the paralyzed hand. Combination of TMS and fMRI investigations demonstrated different cortical reshaping patterns of APB and FD. It was also found that the activated cortical areas of FD were located in bilateral motor cortices, but the area of APB was only located in ipsilateral motor cortex. The cerebral plasticity procedure appeared to be different in the gross and fine motor function recovery processes. It provided a new perspective into the cerebral plasticity induced by CC7 neurotization
Experimental and numerical simulation studies of the squeezing dynamics of the UBVT system with a hole-plug device
In this paper, a method is proposed to secure an autonomous underwater blasting vibration test (UBVT) system with plugs to deep-water rock, and its specific configuration concept and plugging principle are illustrated. Using the principle of statics, a mathematical model is established for the squeezing force in the process of pressing the hole-plug device (HPD) into holes in rocks. The tension-compression test is conducted on the plugs in round granite holes to obtain the axial pressure-displacement curves of the pressing process with the HPD spring parameter K, friction coefficient μ between the HPD and the rock-wall, and the dynamic contact friction attributes between the metallic HPD and the rock-wall of hole in granite. The axial pressure with such parameters as K, μ, and the squeezing velocity v, among others, and the four steps of the pressing process are numerically simulated. The relations of the characteristic squeezing force with K, μ, and v, as well as the mechanisms of these parameters that influence HPD usage and the sensitivity coefficient, are revealed. The findings of the present study provide references for setting the HPD configuration parameters and for formulating plug-specific construction methods
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