14 research outputs found
Numerical Analysis of Partial Abrasion of the Straddle-type Monorail Vehicle running Tyre
The finite element model of the running tyre and the pre-stressed concrete (PC) track beam are created in the study. The wheel-rail contact status under the conditions such as acceleration or braking, lateral deviation, and roll is analysed. The wear law of the running tyre under the operating condition of driving on winding roads is discussed. The results show that the running tyre will unevenly wear when driving on the winding road; the smaller curve radius and the faster speed result in heavier and more uneven wear. There is a larger slip between the running tyre on the inner side of the curve and the rail surface, and this tyre has more uneven wear than the running tyre on the outer side of the curve. The research findings provide a theoretical basis for solving the problem of reducing the uneven wear of the running tyre
A Survey on Secure Wireless Body Area Networks
Combining tiny sensors and wireless communication technology, wireless body area network (WBAN) is one of the most promising fields. Wearable and implantable sensors are utilized for collecting the physiological data to achieve continuously monitoring of people’s physical conditions. However, due to the openness of wireless environment and the significance and privacy of people’s physiological data, WBAN is vulnerable to various attacks; thus, strict security mechanisms are required to enable a secure WBAN. In this article, we mainly focus on a survey on the security issues in WBAN, including securing internal communication in WBAN and securing communication between WBAN and external users. For each part, we discuss and identify the security goals to be achieved. Meanwhile, relevant security solutions in existing research on WBAN are presented and their applicability is analyzed
Adjunctive intra-arterial tenecteplase after successful endovascular thrombectomy in patients with large vessel occlusion stroke (POST-TNK): Study rationale and design
Rationale: Adjunct intra-arterial alteplase has been shown to potentially improve clinical outcomes in patients with large vessel occlusion (LVO) stroke who have undergone successful endovascular thrombectomy. Tenecteplase, known for its enhanced fibrin specificity and extended activity duration, could potentially enhance outcomes in stroke patients after successful reperfusion when used as an adjunct intra-arterial therapy. Aim: To explore the safety and efficacy of intra-arterial tenecteplase after successful endovascular thrombectomy in patients with LVO stroke.
Sample size: To randomize 498 participants 1:1 to receive intra-arterial tenecteplase or no intra-arterial adjunctive thrombolysis therapy.
Methods and design: An investigator-initiated, prospective, randomized, open-label, blind-endpoint multicenter clinical trial. Eligible patients with anterior circulation LVO stroke presenting within 24 h from symptom onset (time last known well) and excellent to complete reperfusion (expanded Thrombolysis In Cerebral Infarction (eTICI) scale 2c–3) at endovascular thrombectomy are planned to be randomized.
Outcomes: The primary outcome is freedom from disability (modified Rankin Scale, mRS, of 0–1) at 90 days. The primary safety outcomes are mortality through 90 days and symptomatic intracranial hemorrhage within 48 h.
Discussion: The POST-TNK trial will evaluate the efficacy and safety of intra-arterial tenecteplase in patients with LVO stroke and excellent to complete reperfusion
POST‐UK (Adjunctive Intra‐Arterial Urokinase After Successful Endovascular Thrombectomy in Patients With Large‐Vessel Occlusion Stroke): Study Protocol of a Multicenter, Prospective, Randomized, Open‐Label, Blinded‐End Point Trial
BACKGROUND
Intra‐arterial infusion of an adjunctive thrombolytic agent after macrovascular recanalization by endovascular thrombectomy was regarded as a promising strategy to promote outcomes of patients with stroke. Given the characteristics of urokinase as an affordable, available, and widely applied medication, especially in Eastern countries, this trial aims to assess the safety and efficacy of intra‐arterial urokinase as adjunct to endovascular thrombectomy in improving outcomes among patients with anterior large‐vessel occlusion stroke after excellent to complete reperfusion.
METHODS
The POST‐UK (Adjunctive Intra‐Arterial Urokinase After Successful Endovascular Thrombectomy in Patients With Large Vessel Occlusion Stroke) trial is a multicenter, prospective, randomized, open‐label, blinded‐end point trial conducted in China. The planned sample size is 498. Those eligible patients with anterior circulation large‐vessel occlusion stroke and achieving excellent to complete reperfusion by endovascular thrombectomy are planned to be consecutively randomized in a 1:1 ratio to the experimental group (a single dose of intra‐arterial urokinase) or to standard of care.
RESULTS
The primary outcome is a freedom from disability (modified Rankin Scale score of 0–1) at 90±7 days. The safety outcomes are mortality within 90±7 days and symptomatic intracranial hemorrhage within 48 hours.
CONCLUSION
The POST‐UK trial will provide valuable insight of efficacy and safety of intra‐arterial urokinase in patients with large‐vessel occlusion stroke after achieving excellent to complete reperfusion by endovascular thrombectomy
Methylprednisolone as Adjunct to Endovascular Thrombectomy for Large-Vessel Occlusion Stroke
Importance
It is uncertain whether intravenous methylprednisolone improves outcomes for patients with acute ischemic stroke due to large-vessel occlusion (LVO) undergoing endovascular thrombectomy.
Objective
To assess the efficacy and adverse events of adjunctive intravenous low-dose methylprednisolone to endovascular thrombectomy for acute ischemic stroke secondary to LVO.
Design, Setting, and Participants
This investigator-initiated, randomized, double-blind, placebo-controlled trial was implemented at 82 hospitals in China, enrolling 1680 patients with stroke and proximal intracranial LVO presenting within 24 hours of time last known to be well. Recruitment took place between February 9, 2022, and June 30, 2023, with a final follow-up on September 30, 2023.InterventionsEligible patients were randomly assigned to intravenous methylprednisolone (n = 839) at 2 mg/kg/d or placebo (n = 841) for 3 days adjunctive to endovascular thrombectomy.
Main Outcomes and Measures
The primary efficacy outcome was disability level at 90 days as measured by the overall distribution of the modified Rankin Scale scores (range, 0 [no symptoms] to 6 [death]). The primary safety outcomes included mortality at 90 days and the incidence of symptomatic intracranial hemorrhage within 48 hours.
Results
Among 1680 patients randomized (median age, 69 years; 727 female [43.3%]), 1673 (99.6%) completed the trial. The median 90-day modified Rankin Scale score was 3 (IQR, 1-5) in the methylprednisolone group vs 3 (IQR, 1-6) in the placebo group (adjusted generalized odds ratio for a lower level of disability, 1.10 [95% CI, 0.96-1.25]; P = .17). In the methylprednisolone group, there was a lower mortality rate (23.2% vs 28.5%; adjusted risk ratio, 0.84 [95% CI, 0.71-0.98]; P = .03) and a lower rate of symptomatic intracranial hemorrhage (8.6% vs 11.7%; adjusted risk ratio, 0.74 [95% CI, 0.55-0.99]; P = .04) compared with placebo.
Conclusions and Relevance
Among patients with acute ischemic stroke due to LVO undergoing endovascular thrombectomy, adjunctive methylprednisolone added to endovascular thrombectomy did not significantly improve the degree of overall disability.Trial RegistrationChiCTR.org.cn Identifier: ChiCTR210005172
Research on Vertical Coupling Dynamics of Monorail Vehicle at Finger-Band
Abstract In view of the fact that exhibits monorail transportation in recent years, the good situation and the lack of straddle-type monorail vehicle vertical dynamics research, the key problems of vertical vibration were studied in this paper: The vertical coupling is between walking tires and finger-band. A dynamic model based on the vertical equivalent stiffness of tire is proposed, the force mode of the tire is determined through the comparison calculation and the dynamics model between walking tires and finger band was established on ADAMS Dynamics Software. By dynamic calculation, the vibration of four running wheels in time and frequency domains is obtained, and the vibration of the front axle of the front bogie is studied in detail; the correctness of the model is confirmed by comparing with the real vehicle test. Finally, the limitations of this paper and the direction of follow-up work are discussed
Research on the Influence of Straddle-Type Monorail’s Pantograph Head Parameter on Power Collection Quality
Abstract At present, the coupling relationship between the pantograph and catenary is not ideal for straddle-type monorail. The power collection quality is poor, and the wear of the contact strip of a pantograph is uneven. Therefore, the key problem of coupling relation between the pantograph and catenary is the dynamics of a pantograph–catenary system. This paper analyzed the modal of catenary through simulation with finite element model and the vibration modal of pantograph multi-rigid-body dynamic model by simulation in multi-body danamics software ADAMS. A rigid-flexible coupling dynamic model of pantograph–catenary system is established. Finally, extensive research has been made on the influence of pantograph head parameters on the power collection quality
Disturbances of the Gut Microbiota and Microbiota-Derived Metabolites in Inflammatory Bowel Disease
Inflammatory bowel disease (IBD), comprising Crohn’s disease (CD) and ulcerative colitis (UC), is characterized as a chronic and recurrent inflammatory disease whose pathogenesis is still elusive. The gut microbiota exerts important and diverse effects on host physiology through maintaining immune balance and generating health-benefiting metabolites. Many studies have demonstrated that IBD is associated with disturbances in the composition and function of the gut microbiota. Both the abundance and diversity of gut microbiota are dramatically decreased in IBD patients. Furthermore, some particular classes of microbiota-derived metabolites, principally short-chain fatty acids, tryptophan, and its metabolites, and bile acids have also been implicated in the pathogenesis of IBD. In this review, we aim to define the disturbance of gut microbiota and the key classes of microbiota-derived metabolites in IBD pathogenesis. In addition, we also focus on scientific evidence on probiotics, not only on the molecular mechanisms underlying the beneficial effects of probiotics on IBD but also the challenges it faces in safe and appropriate application