Determination of 3-deoxy-D-arabino-heptulosonate 7-phosphate productivity and yield from glucose inEscherichia colidevoid of the glucose phosphotransferase transport system

2001 ◽  
Vol 73 (6) ◽  
pp. 530-535 ◽  
Author(s):  
José Luis Báez ◽  
Francisco Bolívar ◽  
Guillermo Gosset
Keyword(s):  
Transport System ◽  
Phosphotransferase Transport System

scholarly journals Evidence for two asymmetric conformational states in the human erythrocyte sugar-transport system

1975 ◽  
Vol 145 (3) ◽  
pp. 417-429 ◽  
Author(s):  
J E Barnett ◽  
G D Holman ◽  
R A Chalkley ◽  
K A Munday
Keyword(s):  
Glucose Transport ◽  
Transport System ◽  
Human Erythrocyte ◽  
Partition Coefficients ◽  
External Medium ◽  
Sugar Transport ◽  
Conformational States ◽  
Glucose Transport System ◽  
Oil Water

6-O-methyl-, 6-O-propyl-, 6-O-pentyl- and 6-O-benzyl-D-galactose, and 6-O-methyl-, 6-O-propyl- and 6-O-pentyl-D-glucose inhibit the glucose-transport system of the human erythrocyte when added to the external medium. Penetration of 6-O-methyl-D-galactose is inhibited by D-glucose, suggesting that it is transported by the glucose-transport system, but the longer-chain 6-O-alkyl-D-galactoses penetrate by a slower D-glucose-insensitive route at rates proportional to their olive oil/water partition coefficients. 6-O-n-Propyl-D-glucose and 6-O-n-propyl-D-galactose do not significantly inhibit L-sorbose entry or D-glucose exit when present only on the inside of the cells whereas propyl-beta-D-glucopyranoside, which also penetrates the membrane slowly by a glucose-insensitive route, only inhibits L-sorbose entry or D-glucose exit when present inside the cells, and not when on the outside. The 6-O-alkyl-D-galactoses, like the other nontransported C-4 and C-6 derivatives, maltose and 4,6-O-ethylidene-D-glucose, protect against fluorodinitrobenzene inactivation, whereas propyl beta-D-glucopyranoside stimulates the inactivation. Of the transported sugars tested, those modified at C-1, C-2 and C-3 enhance fluorodinitrobenzene inactivation, where those modified at C-4 and C-6 do not, but are inert or protect against inactivation. An asymmetric mechanism is proposed with two conformational states in which the sugar binds to the transport system so that C-4 and C-6 are in contact with the solvent on the outside and C-1 is in contact with the solvent on the inside of the cell. It is suggested that fluorodinitrobenzene reacts with the form of the transport system that binds sugars at the inner side of the membrane. An Appendix describes the theoretical basis of the experimental methods used for the determination of kinetic constants for non-permeating inhibitors.

scholarly journals Development of the Methodological Proposals for the Use of Innovative Risk-Based Mechanism in Transport System

2018 ◽  
Vol 7 (4.3) ◽  
pp. 257 ◽  
Author(s):  
Varvara Piterska ◽  
Anatoliy Shakhov ◽  
. .
Keyword(s):  
Risk Management ◽  
Transport System ◽  
Careful Analysis ◽  
Risk Indicators ◽  
Management Mechanism ◽  
Effective Mechanism ◽  
The World ◽  
Risk Situation

It can be concluded that the system of analysis and risk management is an effective mechanism for accelerating of customs clearance and improving of the quality of customs control in the functioning of the transport system. The proposed risk management mechanism for performing customs and technological procedures within the transport system reflects a sequence of actions that involves selecting one or more monitoring objects for careful analysis and determination of risk indicators, followed by a decision on the use of forms and methods of customs control, taking into account the probability the occurrence of potential or real loss. The use of the proposed methodology will significantly shorten the time of customs procedures, and therefore, reduce the time of transportation of goods across the border, exclude the downtime of transports through the implementation of simplified controls taking into account the requirements of the World Trade Organization, as well as the integrated use of the Kyoto Convention on the basis of assessing of the loss from the risk situation. 

scholarly journals DETERMINATION OF THE THROUGHPUT CAPACITY OF STOP POINTS OF URBAN PUBLIC TRANSPORT

2020 ◽  
Vol 17 (2) ◽  
pp. 248-261
Author(s):  
A. I. Fadeev ◽  
E. V. Fomin ◽  
S. Alhusseini
Keyword(s):  
Mathematical Models ◽  
Transport System ◽  
Public Transport ◽  
Throughput Capacity ◽  
Public Transport System ◽  
Simulation Based ◽  
Urban Public Transport ◽  
Random Nature ◽  
Stop Point

Introduction. One of the most important parameters of the transport system is the capacity of line, which in urban public transport system is usually determined by the stop points throughput capacity. When determining the throughput capacity of stop points, it is necessary to consider the random nature of the transport flows at the stop and the process of boarding and alighting passengers. In this work, the stop point is considered as a multi-channel single-phase queuing system (QS). On this basis, an approach to determining the throughput capacity of stop points in urban passenger transport is proposed and justified.Materials and methods. Two mathematical models of a stop point as QS are considered: analytical and simulation. Based on the obtained analysis results from these models, recommendations are offered for calculating the actual throughput capacity of a stop point.Results. In this article, as example a specific stop points are taken, to evaluate the performance of the proposed mathematical models and formulate recommendations to determine its throughput capacity.Discussion and conclusion. The proposed procedure for determining the stop points throughput capacity, consisting of identifying critical stop points with the highest passengers traffic, determining the service process parameters of fleet, and calculating the probability of queue occurrence, allows to set the maximum traffic intensity for the lines of urban public transport.Financial transparency: the authors have no financial interest in the presented materials or methods. There is no conflict of interest.

scholarly journals METHOD OF TESTING THE READINESS OF MEANS OF TRANSPORT WITH THE USE OF SEMI-MARKOV PROCESSES

Transport ◽  
2021 ◽  
Vol 36 (1) ◽  
pp. 75-83
Author(s):  
Anna Borucka
Keyword(s):  
Transport System ◽  
Markov Processes ◽  
Formal Models ◽  
Time Determination ◽  
Semi Markov Processes ◽  
Theoretical Side

In the analysis of the readiness of means of transport, the Markov and semi-Markov processes are particularly applicable, allowing for the description of the usage process over long periods of time, determination of indicators of the exploitability and readiness of the used set of objects, as well as simulation of long-term forecasts of the usage process results. The studies presented in the literature usually concern the theoretical side of the matter, mainly the construction of formal models of the process of changing the operating states of a vehicle. Less attention is paid to the empirical side, especially with regard to the actual conditions of use. Examples of experimental observations presented in the literature most often concern individual cases. This paper lists selected irregularities and presents an example of a study of a real transport system based on semi-Markov processes.

scholarly journals Operation of “russian maglev” transport system and medical-biological safety aspects

2017 ◽  
Vol 3 (3) ◽  
pp. 111-132 ◽  
Author(s):  
Timur D Vlasov ◽  
Artemiy V Rubinskiy
Keyword(s):  
Transport System ◽  
Magnetic Levitation ◽  
Low Frequency ◽  
Practical Significance ◽  
Railway Transport ◽  
Biological Safety ◽  
Biological Studies ◽  
Levitation System ◽  
Magnetic Levitation System

The article deals with the analysis of medical and biological safety of the results of work on the design and model-laboratory experiments of “Russian maglev” transport system. Purpose. The purpose of the work is determination of location and level of field physical characteristics of national magnetic levitation system “Russian maglev”, development of scientifically justified preventive-sanitary suggestions and recommendations necessary for design and application of the systems for protection, control and monitoring of hazardous effects of non-radiation physical fields on passengers, personnel and transported cargo and ecology. Methodology. To achieve the set purpose a review of modern ideas on the influence of constant and low frequency magnetic fields on people was carried out, characteristics of main sources of EMF influence on people during “Russian maglev” technologies operation were studied and described. The obtained results were compared with technical documents on electromagnetic safety. Results. As a result of this work, hygienic requirements for absolute levels and length of unfavourable factors impact on railway transport were determined, which are not mentioned in the active Sanitary Regulations and Instructions. Considering this, recommendations for the most safety placement of MF for people and safety means in crew vehicle were given. Practical significance. The significance of this work is that the preliminary work for medical-biological studies in conditions of full-size model was carried out.

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