NEURON STRUCTURE OF THE GANGLION PLEXUSES IN THE LARGE INTESTINE

Aim of the study: The aim of the work: to study the syncytial connections in the ganglia of the nerve plexuses of the large intestine. Material and research methods: The work was carried out on 30 sexually mature Wistar rats at the age of 3–4 months, having a mass of 180–320 g by the beginning of the experiment. The study used a universal method of impregnation, based on classical impregnation methods: intravascular — Rannier–Goyer and immersion — Bilshovsky–Gros. The study was conducted in 2019–2020. Results: According to our data, the large intestine has intraorgan ganglia located in the intermuscular and submucosal plexuses. The intermuscular plexus (Auerbach) of the large intestine has the form of a network with cells of various shapes and consists of nerve nodes containing cells of types I and II of Dogiel, however, the latter are numerically significantly predominant (20–25 cells or more). Syncytial connections of neurons in the autonomic ganglia of the intestine were constantly detected. These were syncytial connections of processes and bodies of two neurocytes. Protoplasmic processes of nerve cells diverge in different directions, go to meet similar branches, joining them, form a narrow or wide-looped network. Syncytial connections between the bodies of neurons and peripheral processes form closed annular anastomoses. Interfiber cytoplasmic bonds are formed by membrane syncytial fusion. Conclusion. The large intestine has intraorgan ganglia located in the intermuscular and submucosal plexuses. Syncytial connections of neurons in the autonomic ganglia of the intestine were constantly detected. Interfiber cytoplasmic bonds are formed by membrane syncytial fusion.

Optimization of Layout and Pipe Sizes for Irrigation Pipe Distribution Network Using Steiner Point Concept

In tropical countries like India, irrigation is necessary to grow crops in the nonmonsoon period. The conventional methodology for conveying irrigation water from the source to the field is through open canals. However, considering huge losses due to evaporation and percolation, a modern system of irrigation like pipe irrigation network (PIN) is desired. Advancement in technology has led to the progress in the PIN as they are compatible with modern irrigation facilities such as sprinkler and drip irrigation systems. In the present study, the layout of the PIN is designed and optimized in two phases. Initially, the looped network is traced out for the Bakhari distributary of the Kanhan Branch Canal, India. Minimum spanning tree (MST) network is obtained from the looped network using Prim's algorithm to calculate the nodal demands. The layout optimization of the MST is carried out using the Steiner concept to obtain the initial Steiner tree (IST). The steady-state hydraulic analysis and design are carried out for the looped and IST network. The results show that the percentage of length decreasing from the looped network to the MST network is 51.58%. The IST network is the optimized network having the minimum length showing a 12.21% length reduction compared to the MST network. The total reduction in the cost of the Steiner tree is found to be 4.25% compared to the looped network. Steiner concept application to large irrigation networks can reduce the length of the network thereby minimizing the total project cost.

Water Loss Reduction in Water Distribution Networks. Case Study

Water losses on the potable water distribution networks represent an important issue; on the one hand, water loss does not bring money and on the other hand, they modify water flow and pressure distribution on the entire system and this can lead to a cut-off of the water supply. A stringent monitoring of the water distribution network reduces considerably the water losses. The appearance of a leakage inside the distribution network is inevitable in time. But very important is its location and repair time – that are recommended to be as short as possible. The present paper analyses the hydraulic parameters of the water flow inside a supply pipe of a looped network that provides potable water for an entire neighbourhood. The main goals are to optimize these parameters, to reduce water losses by rigorous monitoring and control of the service pressure on the supply pipe and to create a balance between pressure and water flow. The presented method is valid for any type of distribution network, but the obtained values refer strictly to the analysed potable water distribution looped network.

Hardy Cross Method for Pipe Networks

Hardy Cross originally proposed a method for analysis of flow in networks of conduits or conductors in 1936. His method was the first really useful engineering method in the field of pipe network calculation. Only electrical analogs of hydraulic networks were used before the Hardy Cross method. A problem with the flow resistance versus the electrical resistance makes these electrical analog methods obsolete. The method by Hardy Cross is taught extensively at faculties and it still remains an important tool for analysis of looped pipe systems. Engineers today mostly use a modified Hardy Cross method which threats the whole looped network of pipes simultaneously (use of these methods without computers is practically impossible). A method from the Russian practice published during 1930s, which is similar to the Hardy Cross method, is described, too. Some notes from the life of Hardy Cross are also shown. Finally, an improved version of the Hardy Cross method, which significantly reduces number of iterations, is presented and discussed. Also we tested multi-point iterative methods which can be used as substitution for the Newton-Raphson approach used by Hardy Cross, but this approach didn’t reduce number of required iterations to reach the final balanced solution. Although, many new models have been developed since the time of Hardy Cross, main purpose of this paper is to illustrate the very beginning of modeling of gas and water pipe networks or ventilation systems.

Improved Hardy Cross Method for Pipe Networks

Hardy Cross originally proposed a method for analysis of flow in networks of conduits or conductors in 1936. His method was the first really useful engineering method in the field of pipe network calculation. Only electrical analogs of hydraulic networks were used before the Hardy Cross method. A problem with the flow resistance versus the electrical resistance makes these electrical analog methods obsolete. The method by Hardy Cross is taught extensively at faculties and it still remains an important tool for analysis of looped pipe systems. Engineers today mostly use a modified Hardy Cross method which threats the whole looped network of pipes simultaneously (use of these methods without computers is practically impossible). A method from the Russian practice published during 1930s, which is similar to the Hardy Cross method, is described, too. Some notes from the life of Hardy Cross are also shown. Finally, an improved version of the Hardy Cross method, which significantly reduces number of iterations, is presented and discussed.