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Linked article: This Correspondence comments on Hu et al. Click here to view the article. [ABSTRACT FROM AUTHOR]

The slipstream caused by high-speed trains may harm pedestrians and workers trackside. In general, the characteristics of the slipstream are influenced mainly by the nose shape of the train. The present study explores the slipstream caused by high-speed trains with three different horizontal nose profiles based on the results of three-dimensional, improved delayed detached eddy simulation (1DDES) with an unsteady turbulence model and a set of l/8th scaled train models. The results obtained using this numerical methodology are in good agreement with those obtained from corresponding wind tunnel tests. The trackside pressure changes around the train models are also captured and analyzed. The analysis reveals that the width of the nose can significantly influence the magnitude and arrival time of slipstream velocity and pressure peaks. The results and proposed numerical methodology can be used as guidelines for the design of high-speed train nose shapes. [ABSTRACT FROM AUTHOR]

This paper describes techniques developed for conflict detection during plan integration. Agents' intensions are represented with intended goal structure (IGS) and the E-PERT diagrams. Conflicts are classified as goal, plan, and belief conflicts. Before integrating individual plans and detecting plan conflicts, agents first detect and eliminate their goal conflicts by exchanging their IGS. Plan integration is done through merging individual E-PERT diagrams. Project estimation and review technique (PERT) diagrams have been used extensively in the systems analysis area since the 1980s to provide a global consistent view of parallel activities within a project. We extended the PERT diagrams for use in the plan integration activity within multi-agent systems (MAS). The E-PERT diagram contributes to maintain traceable temporal relations among agents' local scheduled actions. Combined with pattern matching, plan conflicts due to resource sharing, or conflicting conditions (i.e., postconditions of one action disabling preconditions of another action) can be detected. The conflict detection techniques are implemented in a sensible agent testbed to promote deployment and performance analysis. Index Terms--Agent, conflict resolution (CR), multi-agent system (MAS), plan integration.

It is well known that the train nose shape has significant influence on the aerodynamic characteristics. This study explores the influence of four kinds of nose shapes (fusiform, flat-broad, bulge-broad, ellipsoidal) on the aerodynamic performance of two opposing high-speed trains passing by each other through a tunnel at 250 km/h. The method of three dimensional, compressible, unsteady Reynolds-averaged Navier-Stokes equations and RNG k-ε double equation turbulence model was carried out to simulate the whole process of two trains passing by each other inside a tunnel. Then the pressure variations on tunnel wall and train surface are compared with previous full-scale test to validate the numerical method adopted in this paper. The assessment characteristics, such as transient pressure and aerodynamic loading, are analyzed to investigate the influence of nose shape on these assessment parameters. It is revealed that aerodynamic performance of trains which have longitudinal nose profile line B (fusiform, flat-broad shape) is relatively better when passing by each other in a tunnel. The results can be used as a guideline for high-speed train nose shape design. [ABSTRACT FROM AUTHOR]

BACKGROUND: Endovascular embolization has been used to control gastrointestinal tumor bleeding. Lots of embolic agents have been applied in embolization, but liquid embolic materials such as Onyx have been rarely used because of concerns about severe ischemic complications. AIM: To evaluate the clinical efficacy and safety of transcatheter arterial embolization (TAE) with Onyx for acute gastrointestinal tumor hemorrhage. MATERIALS AND METHODS: Between September 2011 and July 2013, nine patients were diagnosed as acute gastrointestinal tumor hemorrhage by clinical feature and imaging examination. The angiographic findings were extravasation of contrast media in the five patients. The site of hemorrhage included upper gastrointestinal bleeding in seven cases and lower gastrointestinal bleeding in two cases. TAE was performed using Onyx in all the patients, and the blood pressure and heart rate were monitored, the angiographic and clinical success rate, recurrent bleeding rate, procedure related complications and clinical outcomes were evaluated after therapy. The clinical parameters and embolization data were studied retrospectively. RESULTS: All the patients (100%) who underwent TAE with Onyx achieved complete hemostasis without rebleeding and the patients were discharged after clinical improvement without a second surgery. No one of the patients expired during the hospital course. All the patients were discharged after clinical improvement without a second surgery. Postembolization bowel ischemia or necrosis was not observed in any of the patients who received TAE with Onyx. CONCLUSIONS: TAE with Onyx is a highly effective and safe treatment modality for acute gastrointestinal tumor hemorrhage, even with pre-existing coagulopathy. [ABSTRACT FROM AUTHOR]

In this paper, the transverse equivalent network (TEN) model based on the transmission line theory is employed to analyze and calculate the far-field radiation properties of the Fabry-Perot Resonator (FPR) antenna with perfect magnetic conductor (PMC) ground plane in detail, then the comparative study of the radiation property of FPR antenna with PMC and PEC ground plane is presented. The closed-form expressions for the radiated fields, field peak values, pattern beamwidths and pattern bandwidth of this type of antenna in the E- and H-planes are derived, respectively. The results demonstrate that in theory the radiation property of FPR antenna with two kinds of ground plane is not the same unexpectedly. An interesting characteristic of this type of antenna is that when the PMC acts as the antenna ground plane, the beamwidth and bandwidth of the antenna is increased by a factor of two in general cases, while its peak value of far field is the same as that of the conventional antennas of this class having PEC ground plane. Some results are validated through full-wave simulations of an actual antenna. The original results obtained here lead to a design method for getting the maximum directivity and keeping the bandwidth of this kind of resonant antenna, which is of great significance for antenna designing. [ABSTRACT FROM AUTHOR]

Objective: To investigate the characteristics of cerebral metabolism associated with mild cognitive impairment (MCI) Parkinson's disease (PD), cognitive normal PD and normal control to find a PET biomarker for the diagnose and estimate of PD-MCI. Methods: Forty-seven patients diagnosed with PD (included 15 with mild cognitive impairment) and 20 control subjects were enrolled. All the subjects were evaluated with FDG-PET and clinical scale. The statistical parametric mapping (SPM) were analyzed to determine metabolic patterns that may be useful in differentiating between the three groups. Results: SPM analysis showed that significant hypometabolism were observed in both side of front lobe, parietal lobe, left temporal lobe and left occipital lobe; in the contrast, the relative hypermetabolism had been observed in the cerebellum, vermis, hippocampus and supplement motor area (SMA) in patients with PD-MCI. PD without MCI showed hypometabolism in both side of front lob, caudate and putamen. PD-MCI showed that the significant hypermetabolism were in the insular and cerebellum while hypometabolism were in the both side of occipital compared to PD without MCI. Conclusion: A voxel-by-voxel based SPM method i. e. SPM8 analysis by PET scan is an effective way to analysis the FDG uptake pattern of PD patients. The hypermetabolism in the insula and cerebellum and hypometabolism in the both side of occipital may be a biomarker for make a diagnosis of PD-MCI.

Background: Endovascular embolization has been used to control gastrointestinal tumor bleeding. Lots of embolic agents have been applied in embolization, but liquid embolic materials such as Onyx have been rarely used because of concerns about severe ischemic complications., Aim: To evaluate the clinical efficacy and safety of transcatheter arterial embolization (TAE) with Onyx for acute gastrointestinal tumor hemorrhage., Materials and Methods: Between September 2011 and July 2013, nine patients were diagnosed as acute gastrointestinal tumor hemorrhage by clinical feature and imaging examination. The angiographic findings were extravasation of contrast media in the five patients. The site of hemorrhage included upper gastrointestinal bleeding in seven cases and lower gastrointestinal bleeding in two cases. TAE was performed using Onyx in all the patients, and the blood pressure and heart rate were monitored, the angiographic and clinical success rate, recurrent bleeding rate, procedure related complications and clinical outcomes were evaluated after therapy. The clinical parameters and embolization data were studied retrospectively., Results: All the patients (100%) who underwent TAE with Onyx achieved complete hemostasis without rebleeding and the patients were discharged after clinical improvement without a second surgery. No one of the patients expired during the hospital course. All the patients were discharged after clinical improvement without a second surgery. Postembolization bowel ischemia or necrosis was not observed in any of the patients who received TAE with Onyx., Conclusions: TAE with Onyx is a highly effective and safe treatment modality for acute gastrointestinal tumor hemorrhage, even with pre-existing coagulopathy.

Objective: To assess the utility of triage guidelines for patients with cholelithiasis and suspected choledocholithiasis, incorporating selective use of magnetic resonance cholangiography (MRC) and endoscopic retrograde cholangiopancreatography (ERCP) before laparoscopic cholecystectomy (LC)., Summary Background Data: ERCP is the most frequently used modality for the diagnosis and resolution of choledocholithiasis before LC. MRC has recently emerged as an accurate, noninvasive modality for the detection of choledocholithiasis. However, useful strategies for implementing this diagnostic modality for patient evaluation before LC have not been investigated., Methods: During a 16-month period, the authors prospectively evaluated all patients before LC using triage guidelines incorporating patient information obtained from clinical evaluation, serum chemistry analysis, and abdominal ultrasonography. Patients were then assigned to one of four groups based on the level of suspicion for choledocholithiasis (group I, extremely high; group 2, high; group 3, moderate; group 4, low). Group 1 patients underwent ERCP and clearance of common bile duct stones; group 2 patients underwent MRC; group 3 patients underwent LC with intraoperative cholangiography; and group 4 patients underwent LC without intraoperative cholangiography., Results: Choledocholithiasis was detected in 43 of 440 patients (9.8%). The occurrence of choledocholithiasis among patients in the four groups were 92.6% (25/27), 32.4% (12/37), 3.8% (2/52), and 0.9% (3/324) for groups 1, 2, 3, and 4, respectively (P <.001). MRC was used for 8.4% (37/440) of patients. Patient triage resulted in the identification of common bile duct stones during preoperative ERCP in 92.3% (36/39) of the patients. Unsuspected common bile duct stones occurred in six patients (1.4%)., Conclusions: The probability of choledocholithiasis can be accurately assessed based on information obtained during the initial noninvasive evaluation. Stratification of risks for choledocholithiasis facilitates patient management with the most appropriate diagnostic studies and interventions, thereby improving patient care and resource utilization.

Aim: To compare the effect of ginsenoside Rg1 and its metabolite Rh1 on proinflammatory cytokines and their mRNA expression by THP-1 cells., Methods: Human peripheral blood mononuclear cells (PBMC) were incubated with Rg1 and Rh1 at concentrations of 0.1, 1, 10, and 100 mg/L, and the cell proliferation was measured 24 h after incubation. Radioimmunoassay (RIA) was used to detect the production of proinflammatory cytokines, TNF alpha, IL-1 alpha, and IL-8. TNF alpha mRNA level was detected by reverse transcription polymerase chain reaction (RT-PCR) after administration of Rg1 and Rh1., Results: Rg1 and Rh1 (at concentration of 0.1, 1, 10, 100 mg/L) had no effect on PBMC proliferation. Rh1 1 mg/L could upregulate the productions of TNF (and IL-8 induced by lipopolysaccharides (LPS) 10 mg/L plus phorbol myristate acetate (PMA) 200 nmol/L, however, Rg1 showed an inhibitory effect on TNF alpha production induced by LPS 100 mg/L. Rg1 1 mg/L and Rh1 100 mg/L enhanced the production of IL-1 alpha level in THP-1 cells in the presence of LPS 10 mg/L. RT-PCR revealed that Rh1 stimulated TNF alpha mRNA expression in suitable stimulatory conditions., Conclusion: Rg1 and Rh1 have different effects on the production of cytokines produced THP-1 cells stimulated by LPS and PMA.