The Role of Railway Transport in East-West Traffic Flow Conditions of the Slovak Republic

2018 ◽  
pp. 121-169 ◽  
Author(s):  
Anna Dolinayova ◽  
Lenka Cerna ◽  
Vladislav Zitricky
Keyword(s):  
Traffic Flow ◽  
Slovak Republic ◽  
Railway Transport ◽  
Flow Conditions ◽  
East West

Platelet and Shear Rate Promote Tumor Cell Adhesion to Human Endothelial Extracellular Matrix - Absence of a Role for Platelet Cyclooxygenase

1989 ◽  
Vol 61 (03) ◽  
pp. 485-489 ◽  
Author(s):  
Eva Bastida ◽  
Lourdes Almirall ◽  
Antonio Ordinas
Keyword(s):  
Cell Adhesion ◽  
Shear Rate ◽  
Tumor Cell ◽  
Umbilical Vein ◽  
Blood Platelets ◽  
Flow Conditions ◽  
Tumor Cell Adhesion ◽  
Rate Dependent ◽  
Static Conditions

SummaryBlood platelets are thought to be involved in certain aspects of malignant dissemination. To study the role of platelets in tumor cell adherence to vascular endothelium we performed studies under static and flow conditions, measuring tumor cell adhesion in the absence or presence of platelets. We used highly metastatic human adenocarcinoma cells of the lung, cultured human umbilical vein endothelial cells (ECs) and extracellular matrices (ECM) prepared from confluent EC monolayers. Our results indicated that under static conditions platelets do not significantly increase tumor cell adhesion to either intact ECs or to exposed ECM. Conversely, the studies performed under flow conditions using the flat chamber perfusion system indicated that the presence of 2 × 105 pl/μl in the perfusate significantly increased the number of tumor cells adhered to ECM, and that this effect was shear rate dependent. The maximal values of tumor cell adhesion were obtained, in presence of platelets, at a shear rate of 1,300 sec-1. Furthermore, our results with ASA-treated platelets suggest that the role of platelets in enhancing tumor cell adhesion to ECM is independent of the activation of the platelet cyclooxygenase pathway.

scholarly journals Forensic Investigation of Four Monitored Green Infrastructure Inlets

Water ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 1787
Author(s):  
Leena J. Shevade ◽  
Franco A. Montalto
Keyword(s):  
Measurement Uncertainty ◽  
Green Infrastructure ◽  
Stormwater Management ◽  
Catchment Area ◽  
Low Flow ◽  
Inflow Rate ◽  
Forensic Investigation ◽  
Flow Conditions ◽  
The Mean

Green infrastructure (GI) is viewed as a sustainable approach to stormwater management that is being rapidly implemented, outpacing the ability of researchers to compare the effectiveness of alternate design configurations. This paper investigated inflow data collected at four GI inlets. The performance of these four GI inlets, all of which were engineered with the same inlet lengths and shapes, was evaluated through field monitoring. A forensic interpretation of the observed inlet performance was conducted using conclusions regarding the role of inlet clogging and inflow rate as described in the previously published work. The mean inlet efficiency (meanPE), which represents the percentage of tributary area runoff that enters the inlet was 65% for the Nashville inlet, while at Happyland the NW inlet averaged 30%, the SW inlet 25%, and the SE inlet 10%, considering all recorded events during the monitoring periods. The analysis suggests that inlet clogging was the main reason for lower inlet efficiency at the SW and NW inlets, while for the SE inlet, performance was compromised by a reverse cross slope of the street. Spatial variability of rainfall, measurement uncertainty, uncertain tributary catchment area, and inlet depression characteristics are also correlated with inlet PE. The research suggests that placement of monitoring sensors should consider low flow conditions and a strategy to measure them. Additional research on the role of various maintenance protocols in inlet hydraulics is recommended.

Adherence of platelets to in situ albumin-binding surfaces under flow conditions: role of surface-adsorbed albumin

2012 ◽  
Vol 7 (4) ◽  
pp. 045007 ◽  
Author(s):  
Sanjukta Guha Thakurta ◽  
Robert Miller ◽  
Anuradha Subramanian
Keyword(s):  
Albumin Binding ◽  
Flow Conditions

Haemorheological Effects on Thrombocyte Adhesion and Aggregation Found Under Controlled Flow Conditions

1979 ◽  
Author(s):  
P.D. Richardson
Keyword(s):  
Rate Of Change ◽  
Continuous Observation ◽  
Flow Conditions ◽  
Wide Range ◽  
Stream Migration ◽  
Local Shear ◽  
Videotape Recording ◽  
Controlled Flow ◽  
A Site

Thrombocyte adhesion and aggregation in a vessel or on a chamber wall can be measured most readily if the flow is controlled and steady, and continuous observation is used. Videotape recording is very helpful for subsequent quantification of the dynamics. The adhesion of each thrombocyte can occur for a finite time interval:this interval has been observed to have a wide range. Platelets which escape often leave open a site which attracts other platelets preferentially. The rate of change of adhesion density (platelets/mm2) is affected by the local shear rate and the shear history upstream. Aggregation is affected similarly, and also proceeds with some platelet turnover. The role of erythrocytes in facilitating cross-stream migration of thrombocytes (which can enhance the growth rate of large thrombi) appears due in part to convective flow fields induced by the motion of erythrocytes in a shear flow, which can be demonstrated theoretically and experimentally. Observations of the phenomenlogy of adhesion and aggregation under controlled flow conditions and comparison with fLu id-dynamically based theory allows representation in terras of a small number of parameters with prospects of prediction of behaviour over a wide range of haemodynamic conditions; biochemical changes lead to changes in values of the parameters, so that activating agents and inhibiting agents modify values in different directions.

Bacteria Transport and Deposition under Unsaturated Flow Conditions: The Role of Water Content and Bacteria Surface Hydrophobicity

2008 ◽  
Vol 7 (2) ◽  
pp. 406-419 ◽  
Author(s):  
G. Gargiulo ◽  
S. A. Bradford ◽  
J. Simunek ◽  
P. Ustohal ◽  
H. Vereecken ◽  
...  
Keyword(s):  
Water Content ◽  
Unsaturated Flow ◽  
Surface Hydrophobicity ◽  
Flow Conditions ◽  
Bacteria Transport

Ensuring Safety of Industrial Cargo by Rail Transportation at the Mining Enterprises

2021 ◽  
pp. 56-62
Author(s):  
V.V. Kupriyanov ◽  
◽  
I.S. Bondarenko ◽  
Keyword(s):  
Information Filtering ◽  
Mining Industry ◽  
Organizational Factors ◽  
Rail Transportation ◽  
Railway Transport ◽  
Control Factors ◽  
Detailed Assessment ◽  
Personnel Safety

The common problem was studied concerning the personnel safety and the operation of railway transport during industrial cargo transportation. Statistical and technical analysis were conducted related to the conditions and reasons of railway accidents caused by various hazardous factors and occurred over the past 15 years in the mining industry of Russia. The study based on natural, technical, and organizational factors showed that there is a steady tendency towards the preservation of the number of accidents such as train collisions, fires, and derailments. Despite the measures taken, such accidents do occur resulting in fatal accidents. The situation is explained by the fact that safety of rail transport is conditioned by the factors that can be divided into difficult-to-control and complex (coordinated by action). The differences between complex factors caused by the railway technology and difficult-to-control factors, which include natural factors or their combination with the stimulated factors are studied in the article. Study of the evidence including the details of the development of fires and derailments of trains from the rails, the consequences of such accidents and conclusions about their causes shows that the additional calculations and classification of the difficult-to-control factors in combination with other causes allow to give a more detailed assessment of the nature of difficult-to-control factors and the interrelationship between them. Through this it becomes possible to detect the maximum number of violations. It is concluded that improving railway safety is possible only with a differentiated approach to the role of each group of factors including difficult-to-control factors, and the ability of personnel to influence the occurrence and development of accidents. The time characteristics of railway accidents are considered. The idea of automated information filtering of clogged messages in the analysis of accidents is formulated.

Concorrenza e regolazione nel settore ferroviario: l'importanza del materiale rotabile

2009 ◽  
pp. 47-72
Author(s):  
Carlo Cambini
Keyword(s):  
Jel Classification ◽  
Railway Transport ◽  
Transport Regulation ◽  
Market Competitiveness ◽  
Railway Industry ◽  
Pros And Cons ◽  
Overall Efficiency ◽  
Barrier To Entry ◽  
The Uk

- The liberalization process in the railway industry is highly influenced by the availability of rolling stocks. Although these assets are duplicable and cannot therefore be defined as essential facilities, evidence from many countries shows that they represent the most relevant barrier to entry in the market. In this paper, following the UK experience, we analyse the role of the rolling stocks and the hypothesis of a vertical separation of these assets from the present owner, i.e. the incumbent operator Trenitalia SpA. We therefore evaluate the pros and cons of a potential de-integration of the Italian railway industry in order to enhance market competitiveness and the overall efficiency of this industry. . Keywords: railway transport, regulation, competition, essential facilities Parole chiave: trasporto ferroviario, regolazione, concorrenza, asset essenziali . Jel Classification: L43 - L51 - L92

Study of the Response of PW Traffic Flow Model to a Bottleneck on a Circular Road and its Suitability for Heterogeneous Traffic Conditions

2021 ◽  
Vol 9 (4) ◽  
pp. 460-463
Keyword(s):  
Fluid Flow ◽  
Traffic Flow ◽  
Flow Model ◽  
Equation Model ◽  
Heterogeneous Traffic ◽  
Flow Conditions ◽  
Flow Models ◽  
Traffic Conditions ◽  
Model Response ◽  
Traffic Flow Models

The traffic flow conditions in developing countries are predominantly heterogeneous. The early developed traffic flow models have been derived from fluid flow to capture the behavior of the traffic. The very first two-equation model derived from fluid flow is known as the Payne-Whitham or PW Model. Along with the traffic flow, this model also captures the traffic acceleration. However, the PW model adopts a constant driver behavior which cannot be ignored, especially in the situation of heterogeneous traffic.This research focuses on testing the PW model and its suitability for heterogeneous traffic conditions by observing the model response to a bottleneck on a circular road. The PW model is mathematically approximated using the Roe Decomposition and then the performance of the model is observed using simulations.

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