Entrance Part Research Articles

Archaeological research on the Kanka fortress city: between nomads and farmers

The settlement of Kanka is one of the largest urban centres on the right bank of the Syrdarya. It comprises a citadel, three shakhristans, each surrounded on three sides by defensive walls, and a suburb of rabad. The fourth side of the settlement bordered the riverbank, along which a wall also ran. A significant object, discovered during the excavations of Shakhristan 1 was the city temple, which was a large monumental structure. The core of the temple complex was a square hall surrounded by bypass corridors. The walls of the temple were decorated with paintings and relief moldings. New research in the settlement was conducted on the eastern part of the city temple, the supposed entrance part site of the temple complex. The archaeological excavations at the Kanka monument have yielded insights into the lifestyle of an outpost city situated at the border of the territories of nomads, pastoralists, and farmers in ancient Central Asia. The findings indicate that ancient nomadic populations likely played a significant role in the dissemination of scientific progress. Through their extensive migrations and cultural interactions, they could have served as conduits for exchanging knowledge and technological innovations among disparate regions.

Insight into the Inhibitory Mechanisms of Hesperidin on α-Glucosidase through Kinetics, Fluorescence Quenching, and Molecular Docking Studies.

The α-glucosidase inhibitor is of interest to researchers due to its association with type-II diabetes treatment by suppressing postprandial hyperglycemia. Hesperidin is a major flavonoid in orange fruit with diverse biological properties. This paper evaluates the effects of hesperidin on α-glucosidase through inhibitory kinetics, fluorescence quenching, and molecular docking methods for the first time. The inhibition kinetic analysis shows that hesperidin reversibly inhibited the α-glucosidase activity with an IC50 value of 18.52 μM and the inhibition was performed in an uncompetitive type. The fluorescence quenching studies indicate that the intrinsic fluorescence of α-glucosidase was quenched via a static quenching process and only one binding site was present between the hesperidin and α-glucosidase. The interaction between them was spontaneous and mainly driven by hydrogen bonds, as well as hydrophobic forces. Furthermore, the molecular docking results suggest that hesperidin might bond to the entrance or outlet part of the active site of α-glucosidase through a network of five hydrogen bonds formed between hesperidin and the four amino acid residues (Trp709, Arg422, Asn424, and Arg467) of α-glucosidase and the hydrophobic effects. These results provide new insight into the inhibitory mechanisms of hesperidin on α-glucosidase, supporting the potential application of a hesperidin-rich orange product as a hypoglycemic functional food.

ECONOMIC OBSERVATION OF NEW WATER SUPPLY DESIGNS

New constructions of water transmission structures and problems of their improvement are presented in the scientific work. The significance of the invention presented in this work is that the entrance part of the duiker is made in the form of a slotted hole with a length equal to the diameter of the pipe and located along the axis of the pipe, 1/8 of the diameter of the pipe. As a result of this work, it is expected that the economic efficiency will increase several times through the improvement of water transmission structures, including the introduction of new constructions of duikers into production.

DETERMINATION OF MORPHOMETRY AND VOLUME OF THE INTERNAL AUDITORY CANAL

OBJECTIVE: The internal auditory canal (IAC) also known as internal acoustic meatus is a bone channel that connects the internal ear to the posterior cranial fossa. The mean length is approximately 1 cm. The edge of the IAC is called internal acoustic pore (IAP), and the edge of this aperture is blunt and rounded. Important formations such as facial nerve, vestibulocochlear nerve, labyrinth artery and labyrinth vein pass through the IAC. In addition, on the precise determination of the morphometry in surgical interventions on the temporal lobe, MAI is vital. Therefore, in this study, it was aimed to determine the morphometry and volume of MAI.MATERIAL AND METHODS: The study was carried out on the CT images of 210 individuals randomly from the normal population between the ages of 10-90. Morphometric measurements of IAC (lateral angle (LA), canal length, anteroposterior (AP), diameter of IAP, distance from IAP to vestibular aqueduct (VA)) were performed. In addition, the shape and volume of IAC was determined in this study. Cases were divided into 7 different subgroups, 10-14, 15-20, 21-30, 31-40, 41-50, 51-60 and 61 years old, depending on their age.RESULTS: In this study, CT images of 210 patients were analyzed. The mean length of the MAI was 9.5±1.6mm, the AP diameter was 6.3±1.5mm, the distance from the entrance part to the VA was 15.1±6.64mm, the volume was 290±120mm3, and the LA was 50±14º.CONCLUSIONS: When the outcome data were compared by gender, it was found statistically significant that the right AP diameter was higher in men, the length of the right MAI and both sides LA were higher in women. In addition, when the volumes of MAI were compared by age groups, it was determined that the 10-14 age group was smaller than the other age groups.

Evaluation of Centrifugal Force, Erosion, Strain Rate, and Wall Shear in a Stairmand Cyclone

In the present study, imperative parameters including centrifugal force, erosion, streamline, strain rate, and wall shear are evaluated in a cyclone separator. The flaw of the cyclone surface due to erosion is an acute problem in the industry. According to the great importance of the centrifugal force on the separation phenomenon, a comprehensive study is conducted. A computational fluid dynamics (CFD) simulation is realized by applying a Reynolds stress turbulence model (RSM), and particle–air interactions were modeled using a discrete phase model (DPM). The result shows a good agreement between the experimental data and CFD simulation on the tangential velocity and pressure drop. The maximum deviation of the validation process is 6.8%. It is found that the centrifugal force within the cyclone is increased with an enhancement in the inlet velocity. The separation efficiency indicates an increase–decrease treatment in various inlet velocities with inlet velocity up to 16 m⋅s−1 but decreases slightly at a velocity of 20 m⋅s−1. The pressure increases proportionally with inlet velocity. The best performance with the highest separation efficiency (99%) and pressure drop (416 Pa) obtains at the inlet velocity of 16 m⋅s−1 and mass flow rate of 0.01 kg⋅s−1. In addition, the maximum erosion rate was created in the entrance and conical part of the cyclone.

Ice in caves and its effect on thermal inversion and permafrost in the case of the Velika ledena jama v Paradani, Smrekova draga and neighbouring dolines

In the Velika ledena jama v Paradani, in the karstic blowholes on the slopes of Smrekova draga and in the nearby dolines I measured and interpreted air temperatures and the effect of the summer outflow of cold air from them into the surrounding area. In winter, cold air enters the cave, radically cooling the entrance part of the cave, where for this reason there is permanent cave ice. The summertime circulation is reversed: emerging from the inner part of cave, which has an average temperature of around 4° C, is air which only when it transits through the sub-cooled entrance part is then cooled to around 1° C. This air comes to the surface and in the hollow at the cave entrance maintains a distinct thermal inversion during the warm part of the year. There is a similar air circulation and similar development of annual temperatures observed at the vents, where cave air emerges through rubble spread over cave entrances on slopes or at the bottom of dolines. The stable summer air temperatures of around 1° C in the vents where I conducted measurements indicate that underneath them there is also permafrost or sub-cooled rock and permanent ice. This is created and preserved, just like in the caves, due to the advection of cold air in winter. In Trnovski gozd, such karstic permafrost is found at an altitude of 1,100 m above sea level. The outflow of cold air from the vents in the summer, just like inside the cave, causes a distinct thermal inversion in dolines on the surface.

Dental health in patients with inflammatory bowel disease and the role of biomarkers in diagnosis

Because the oral cavity is the entrance portal and part of the gastrointestinal tract, oral manifestations occur in patients with inflammatory bowel disease (IBD). Oral manifestations of IBD manifest as a systemic complication or extraintestinal manifestation that may precede, exacerbate, or regress with changes in disease severity. Some of these manifestations are aphthous ulcers, gingivitis, periodontitis, halitosis and others. The oral cavity is one of the most affected areas in patients with CKD - 25-30% of patients. The aim of the present study is to investigate the relationship between dental health and chronic inflammatory bowel disease and the role of biomarkers in their diagnosis. For the period between December 2020 and March 2021 is conducted a systematic analysis of scientific publications in the available databases (PubMed, BioMedCentral, ScienceDirect, Scopus, Web of Science), examining the relationship between dental health and chronic inflammatory bowel disease and the role of biomarkers in their diagnosis.

Dominance of Arcobacter in the white filaments from the thermal sulfidic spring of Fetida Cave (Apulia, southern Italy)

The thermal spring of Fetida Cave, a still active sulfuric acid cave opening at sea level and located in Santa Cesarea Terme, southeastern Salento (Apulia region, Southern Italy) hosts abundant floating white filaments. The white filaments were mainly composed of sulfur crystals surrounded by microbial mass of the phyla Epsilonbacteraeota, Proteobacteria, Bacteroidetes, and Patescibacteria. The most abundant genus in the white filaments collected from the waters in the innermost part of the cave dominated by sulfidic exhalations was Arcobacter. This abundance can be related to the higher concentration of sulfide dissolved in water, and low oxygen and pH values. Conversely, lower Arcobacter abundances were obtained in the filaments collected in the entrance and middle part of the cave, where sulfidic water mixes with seawater, as the cave is subjected to tides and the mixing of fresh (continental) with marine water. The geochemical analysis of water and atmospheric gases confirmed these environmental constraints. In fact, the highest concentrations of H2S in the air and water were recorded closest to the spring upwelling in the innermost part of the cave, and the lowest ones near the cave entrance. The metabolic versatility of Arcobacter might provide a competitive advantage in the colonization of water bodies characterized by high sulfide, low oxygen, and dynamic fluid movement.

Caves and bats: Morphological impacts and archaeological implications. The Azé Prehistoric Cave (Saône-et-Loire, France)

The Prehistoric Cave at Azé (France) was divided in two parts by calcite flowstone. This isolated the innermost parts of the cave from the entrance, which remained connected to the surface. Since the closure, bats have not been able to access the cave beyond the flowstone blockage. They have been present only in the cave entrance. The byproducts released by bats had a considerable effect on this entrance part. Gaseous exhalations have changed the composition of the surrounding atmosphere, leading to the development of dome-shaped cupolas and other wall weathering features. Guano deposits built up causing the formation of aerosols and acidic leachates. The resulting corrosion of the limestone has led to the formation of phosphate deposits and biogenic karst. The rate of retreat of the cave walls has been estimated at 5 to 7 mm/ka. Corrosion has also affected archaeological artefacts, as well as any traces left on the walls by humans or animals. Bioglyphs linked to bears as well as anthropic graffiti have completely disappeared from the part of the cave used by bats.

SOĞMATAR

Located on the Individual Mountains, about 70 km. southeast of Şanlıurfa provincial center, Soğmatar, starting from the Chalcolithic Age due to the abundance of water resources, the Middle and Early Bronze Age, The Iron Age (Bc I. Bin), the Roman period and the Islamic period until the present day uninterrupted settlement, especially in the 2nd century AD. In the 19th century, the moon came to the forefront with the worship of the God of Sin. In addition to being used as a temple area, Soğmatar was also used as a necropolis area in the Early Bronze Age and roman times. Some of the rock tombs in the necropolis area built in the Early Bronze Age were replaced during the Roman period and were reused. These tombs, which were opened in the well-entrance plan, were extended to the south during the Roman period, the well entrance part was extended to the south, the stairway corridors were opened, the entrance part was expanded and the wall cells where the dead were placed on 3 walls were opened. Some of the tombs were left unfinished during this change, so these tombs show architectural features of both the Early Bronze Age and the Roman rock tombs. There are also numerous quarries because of its low rocky hills. Water wells opened to bedrock in antiquity are still used today.

Novel designs for the reliability and safety of supercritical water oxidation process for sludge treatment

For strengthening the safety and reliability for supercritical water oxidation (SCWO) process, the essential causes and solutions of key challenges such as the high corrosion risk of the heat-exchanger and the entrance part of SCWO reactor, the blockage problems resulted from the solid deposition, and the safety and environmental issues caused by the emergency discharge of supercritical aqueous fluids, were investigated theoretically and experimentally. The thermodynamic state division between chemical- and electrochemical corrosion and the corrosion sensitive temperature range of 280−450 °C featuring the predominant electrochemical corrosion were proposed. A set of optimized parameters for the petrochemical sludge treatment such as a temperature of 520–580 ℃, a pressure of 23−25 MPa, and an oxidation coefficient of 1.1–1.3, which not only can ensure the high enough removal rate of organic pollutants but also prevent the corrosion of construction materials as much as possible; the critical velocity of conveying fluid for avoiding the deposition of solid particles were also obtained. On the bases of innovatively developing the “indirect heat transfer” unit, the mixing-preoxidation equipment, the oxygen removal process for SCWO effluents, and the emergency discharge protection device, a novel SCWO process and its corresponding control scheme were proposed and analyzed.

Inhibitory effect of corosolic acid on α-glucosidase: kinetics, interaction mechanism, and molecular simulation.

The suppression of α-glucosidase activity to retard glucose absorption is an important therapy for type-2 diabetes. Corosolic acid (CRA) is a potential antidiabetic component in many plant-based foods and herbs. In this study, the interplay mechanism between α-glucosidase and corosolic acid was investigated by several methods, including three-dimensional fluorescence spectra, circular dichroism spectra, and molecular simulation. Corosolic acid significantly inhibited α-glucosidase reversibly in an uncompetitive manner and its IC50 value was 1.35 × 10-5 mol L-1 . A combination of CRA with myricetin exerted a weak synergy against α-glucosidase. The intrinsic fluorescence of α-glucosidase was quenched via a static quenching course and the binding constant was 3.47 × 103 L mol-1 at 298 K. The binding of CRA to α-glucosidase was mainly driven by hydrophobic forces and resulted in a partial extension of the protein polypeptide chain with a loss of α-helix content. The molecular simulation illustrated that CRA bound to the entrance part of the active center of α-glucosidase and interacted with the amino acid residues Ser157, Arg442, Phe303, Arg315, Tyr158, and Gln353, which could hinder the release of substrate and catalytic reaction product, eventually suppressing the catalytic activity of α-glucosidase. These results may suggest new insights into corosolic acid from food sources as a potential α-glucosidase inhibitor that could better control diabetes. © 2019 Society of Chemical Industry.

Анализ пространственной неравномерности потока во входном сечении осерадиального рабочего колеса центробежной компрессорной ступени в режимах регулирования

The article presents an analysis of the experimental data on testing a centrifugal compressor stage on regulation modes by changing the rotational speed of the rotor and the turning angle of the blades in the inlet guide vane unit. The distribution of the angles of attack at the entrance section of the impeller in relation to the blade height is obtained. It is established that a significant difference in the angles of attack from the plug to the periphery influences the polytropic efficiency of the compressor stage. Recommendations are given on the improvement of the mechanism of regulation by the inlet guide vane unit and on the choice of the optimum diameter for the entrance part of the driving impeller blades.

Flow characteristics of supersonic gas passing through a circular micro-channel under different inflow conditions**Project supported by the National Natural Science Foundation of China (Grant No. 11802264) and the Natural Science Foundation of Jiangsu Province, China (Grant No. BK20180896).

Gas flow in a micro-channel usually has a high Knudsen number. The predominant predictive tool for such a micro-flow is the direct simulation Monte Carlo (DSMC) method, which is used in this paper to investigate primary flow properties of supersonic gas in a circular micro-channel for different inflow conditions, such as free stream at different altitudes, with different incoming Mach numbers, and with different angles of attack. Simulation results indicate that the altitude and free stream incoming Mach number have a significant effect on the whole micro-channel flow field, whereas the angle of attack mainly affects the entrance part of micro-channel flow field. The fundamental mechanism behind the simulation results is also presented. With the increase of altitude, thr free stream would be partly prevented from entering into micro-channel. Meanwhile, the gas flow in micro-channel is decelerated, and the increase in the angle of attack also decelerates the gas flow. In contrast, gas flow in micro-channel is accelerated as free stream incoming Mach number increases. A noteworthy finding is that the rarefaction effects can become very dominant when the free stream incoming Mach number is low. In other words, a free stream with a larger incoming velocity is able to reduce the influence of the rarefaction effects on gas flow in the micro-channel.

Spatial distribution and vertical profile of heavy metals in marine sediments around Iran's special economic energy zone; Arsenic as an enriched contaminant

Surface sediments (n = 35) and a core sample around Pars Special Economic Energy Zone were analyzed to address spatiotemporal variations of heavy metals. Enrichment factors classified the elements as: (1) poorly enriched, geogenic elements (Co, Cr, Fe, Li, Mn, Mo, Ni, Ti, and V), (2) minimal enriched elements (Zn and Mg), (3) moderately enriched elements (Ag, Cd, Pb, Se, and Sr), and (4) significantly enriched element (As and Hg). The core profile showed that As, Hg, Ag, and Cd had considerable anthropogenic inventories. Arsenic levels were continuously increasing toward the top of the core and sedimentary cycling was not an effective factor on its enrichment. Pollution load index classified the area as a severely affected region and Risk Index values suggested that 57% of the sediments had a moderate potential risks. The mapping techniques proposed a polluted and hazardous patch at the entrance and center part of the Nayband Bay.

Nanovortex evolution in entrance part of the 2D open type long nanocavity

Nanovortex evolution in entrance part of the 2D open type long nanocavity

Новые данные о позднеплейстоценовых – раннеголоценовых каменных индустриях на территории Северного Вьетнама

Purpose. Since the 1970s, about a dozen caves and rock shelters have been discovered and explored in the limestone massifs of the Cuc Phuong National Park (North Vietnam), in which stone artifacts, human remains and animal bones belonging to the late Paleolithic-Neolithic period have been found. Archaeological research of the 2012 joint Russian-Vietnamese archaeological expedition extended the list of archaeological sites with a newly discovered cave Diem with a large number of stone products, the complex of faunal and anthropological material. The height of the cave Diem above sea level is 100 m, the entrance is oriented to the North-East. The illuminated entrance part of the cave has a tube-like shape about 30 m long and 5 to 10 m wide. Extending deep into the limestone massif in the form of karst cavities, the cave has a total area of about 500 m². Results. In 2013, the site explored in 2012 had the excavation area of 5 m². In 2014, the area of the excavation was expanded in the North-West direction by 3 m², thus the total of the investigated area was 9 m². In addition to the mechanically mixed upper layer, which included multi-temporal cultural remains, three large cultural and lithological units, numbering 2 118 stone artifacts belonging to the late Paleolithic – Neolithic were identified during the excavation work. In the first cultural-lithological division, there were 39 fragments of ceramics along with stone products. The anthropological material found is represented by a cluster of highly charred and fragmented human bones, presumably of one person. In layer 2, apart from the stone products researchers found a burial of a man whose bone remains were fragmented but were not exposed to fire, as in layer 1. In the roof of layer 3, there was discovered a burial of a woman. More than 1000 bone fragments of reptiles, birds and mammals were collected within the two lower cultural-lithological units. Conclusion. The ceramics found in layer 1 of the Diem cave allows us to correlate it with the Neolithic culture of Da But, whose period of existence varies in the range of 7000-4000 ka. A powerful block horizon located in layer 2 indicates a strong earthquake whose traces are observed in the same stratigraphic conditions in all the caves of the region under study. The absence of ceramics in cultural unit 2 can be attributed to the early Holocene period (about 10 000 ka). The estimated age of layer 3 of the Diem cave is currently difficult to define. Based on preliminary results, we can suppose that this location belongs to cave sites of the commune Thanh Yen, such as Con Moong and Mang Chieng. Culturally and chronologically it corresponds to the culture of Hoa Binh.

Numerical analysis of the axial heat conduction with variable fluid properties in a forced laminar flow tube

In this article, a theoretical model is developed to investigate the effects of the axial heat conduction on the laminar forced convection in a circular tube with uniform internal heat generation in the solid wall. In the current work, three different fluids, i.e. water, n-decane and air, are selected on purpose since their thermophysical properties show different behavior with temperature. The effects of the axial heat conduction with varying dynamic viscosity and/or varying thermal conductivity are investigated in a systematic manner. Results indicate that the variable-property effects could alleviate the reduction in Nusselt number (Nu) due to the axial heat conduction. For the case of Peclet number (Pe) equal to 100, wall thickness to inner diameter ratio of 1 and solid wall to fluid thermal conductivity ratio of 100, the maximum Nu deviation between constant and variable properties are up to 7.33% at the entrance part for water in the temperature range of 50°C, and 4.45% at the entrance part for n-decane in the temperature range of 120°C, as well as 2.20% at the ending part for air in the temperature range of 475°C, respectively. In addition, the average Nu deviation for water, n-decane and air is 3.24%, 1.94% and 1.74%, respectively. Besides, Nu decreases drastically with decreasing Pe when Pe⩽500 and with increasing solid wall to fluid thermal conductivity ratio (ksf) when ksf⩽100. It is also found that variable properties have more obvious effects on the velocity profile at the upstream part while more obvious effects on the temperature profile at the downstream part.

PECULIARITIES OF THE SURFACE FLAW DETECTION BY ELASTIC WAVES SIMULATED BY PULSE-LASER RADIATION

Laser pulse simulation of the surface waves and its receiving by contact piezoelectric probes is perspective direction to detect surface defects. The aim of this work was to determine optimal conditions for detection of the real fatigue cracks of nearly microns width and surface pores by moving depending on the position of the center of a laser beam laser beam spot. The objects of research were metal specimens with crack’s width of 8 m up to 0,5 mm and depth ≈ 400– 500 mm up to ≈ 200 mm. Cylindrical hole by ≈ 1 mm diameter used as a model pore. An experimental installation used consisted of the pulse laser light emission source with laser wavelength of 1.06 m and laser pulse duration of ≈ 20 ns. An arrangement to adjust the laser beam spot geometry in the form of a long strip and a circle was applied. Surface waves were received by the 2.7 MHz frequency probe, and processed with use of a «Spectronic» TDS 3052B oscilloscope. The laws of acoustical signal amplitude and its form changes vs. the laser beam spot geometry and its position in regard to defect were determined. We discovered that optimal conditions for flaw detection took place when the laser beam spot moving trough the defect’s range – crack and pore. In the first case amplitude growth of the signal was up to 7–8 time – like as resonance conditions realized. And the ratio of the laser’s beam spot width (as long strip) to wave length were ≈ 1.8–2.2. The more informative parameter to find crack with small width (≈ 0.5mm) was the acoustical pulse spectrum or the pulse entrance part. Thus, the further increasing of the surface flaw detection may be realized by laser simulation of the surface waves controlling the form of the moving spot of laser beam. New possibilities to increase sensitivity and reliability of ultrasonic evaluation surfaces in objects with complicated profile and fare accessible places are to be arise.

Simulation of Hydraulic Characteristic of Injecting Cable into Coiled Tubing

In order to control and monitor downhole equipment, it is needed to inject cable into coiled tubing. Being directly against the drawback of the traditional injecting method, a new method of adding pressurized water has been put forward. By using Workbench software, this paper researched the regular pattern that water flow’s pressureaffects cable in coiled tubing after it has various deformations in both entrance and main part of coiled tubing, taking 25mm diameter coiled tubing with 3mm diameter cable as an example. It also simulated the effects of water flow toward cable in coiled tubing as well as how the different diverging distances of entrance for injection affects the speed of cable during injection, taking 50.8mm diameter coiled tubing with 5.6 mm diameter cable as an example. It determined the optimal position of cable entrance and provided the theoretic foundation for the possibility and practical manipulation of the new method for injecting cable into coiled tubing.