Potential prophylactic efficacy of mast cell stabilizers against COVID-19 vaccine-induced anaphylaxis

To fight against coronavirus disease 2019 (COVID-19), the vaccination is currently the most effective approach. However, in addition to common systemic side effects, the vaccines can cause serious allergic reactions or anaphylaxis. In anaphylaxis, the exposure to the allergen causes a sudden release of chemical mediators from mast cells, for which adrenaline is the drug of first choice. In our previous basic studies, in addition to adrenaline, anti-allergic drugs (olopatadine, loratadine, tranilast and ketotifen), antibiotics (clarithromycin), corticosteroids (hydrocortisone and dexamethasone) and certain food constituents (caffeine and catechin) inhibited the process of exocytosis and showed their effectiveness as highly potent mast cell stabilizers. In these studies, since mast cells were pre-incubated with these drugs or the food constituents before exocytosis was induced, the findings strongly indicated their prophylactic efficacy in stabilizing mast cells. Considering such pharmacological properties of these commonly prescribed medications or the food constituents, their prophylactic use may potentially be beneficial in preventing anaphylaxis caused by COVID-19 vaccination.

Seismic Response Control of Elevated Water Tank using Base Isolation: A Review

Earthquake events are not something which can be avoidable. The Indian subcontinent has a background marked by devasting quakes. Quakes are generally caused when the stone underground out of nowhere breaks along an issue. Ground shake is caused by seismic waves due to sudden release of energy. The Centre of earthquake vibration is known as epicentre. Due to earthquake millions of lives are lost which can never be affordable. Most of the structures are subjected to vibrations; it causes destruction of country’s infrastructure. In the recent earthquakes many well designed concrete structures have been severely damaged or collapsed. To protect structures from response reduction of structures and important harm under such serious earthquakes has become a vital theme in structural engineering. In this investigation, we evaluated seismic performance of staging system of elevated water storage tank with or without Base Isolation by using SAP2000. From this examination the powers following up on elevated water tank because of seismic powers are determined for zone IV.

Discontinuity in equilibrium wave–current ripple size and shape caused by a winnowing threshold in cohesive sand–clay beds

Sediments composed of mixed cohesive clay and non-cohesive sand are widespread in a range of aquatic environments. The dynamics of ripples in mixed sand–clay substrates have been studied under pure current and pure wave conditions. However, the effect of cohesive clay on ripple development under combined currents and waves has not been examined, even though combined flows are common in estuaries, particularly during storms. Based on a series of large flume experiments on ripple development under combined flows, we identified a robust inverse relationship between initial bed clay content, C0, and ripple growth rate. The experimental results also revealed two distinct types of equilibrium combined-flow ripples on mixed sand–clay beds: (a) large asymmetrical ripples with dimensions and plan geometries comparable to clean-sand counterparts for C0 ≤ 10.6%; and (b) small, flat ripples for C0 > 11%. The increase in bed cohesion contributed to this discontinuity, expressed most clearly in a sharp reduction in equilibrium ripple height, and thus a significant reduction in bed roughness, which implies that the performance of existing ripple predictors can be improved by the incorporation of this physical cohesive effect. These improvements are particularly important for sediment transport and morphodynamic models in muddy estuarine environments. For C0 ≤ 10.6%, strong clay winnowing efficiency under combined flows resulted in the formation of equilibrium clean-sand ripples and clay loss at depths far below the ripple base. In natural environments, this ‘deep cleaning’ of bed clay may cause a concurrent sudden release of a large amount of pollutants during storms, and lead to a sudden reduction in post-storm resistance to erosion of mixed sand–clay substrates.

INFLUENCE OF TECTONIC DISTURBANCES OF COAL LAYER ON HIS GAS DYNAMIC STATE

Problem Statement and Purpose. At one of the coal mines of the Donetsk basin, there was a sudden release of coal and gas. The peculiarity of this case is that the accident happened in the place of the alleged development of a geological disturbance, but without any visible signs of this. Inspection of the ejection site and adjacent horizons made it possible to conclude that the emergency site is located in the place of the plicative disturbance development. Thus, it is necessary to study in more detail the influence of disturbed zones hidden nature on the gas-dynamic state of the reservoir, as well as to develop and implement methods for determining such zones. Data & Methods. To achieve this goal, a new method was tested, based on the property of structureless substances to form crystal-like units. This phenomenon has been studied for decades; therefore, such new formations have long been given the name quasicrystals. It was noted that the increase in the concentration of such forms is associated with the presence of geological disturbances. Consequently, the increase in quasicrystals in the rock is an indicator of its disturbance due to the influence of tectonic pressure. Thus, in order to test the technique and reveal the hidden geological disturbance of the coal seam, coal samples were taken, microstructural features were studied, and the strength of the coal seam was measured at 56 points. Result. As a result the values of the concentration of quasicrystals, data on the strength of the formation were obtained, a schematic map of the development of the disturbance in this area was built, its contours were determined, the center of the disturbed zone was identified and the role of such disturbances in the outburst hazard of the formation was substantiated. It has been established that geological disturbances, even of plicative nature, have a high degree of fracturing. Such pores and cracks in coal reduce the strength properties and are able to concentrate sufficient volumes of gas for manifestation of GDP.

The Parthians’ Failed Vassalage of Syria: The Shortsighted Western Policy of Phraates Ii and the Second Reign of Demetrius Ii (129–125 BCE)

SummaryBy 128 BCE the Parthians had emerged temporarily as the de facto leading power throughout the Hellenistic Middle East. Their defeat of Demetrius II’s invasion of Mesopotamia in 138 BCE had furthered their heated rivalry with the Seleucids; however, their destruction of Antiochus VII’s invasion of Mesopotamia and Media in 129 BCE finally ended the threat of the Seleucids to their eastern lands. For the first time in their history, the Parthians considered expanding their hegemony over Armenia, Syria, and the regions along the Eastern Mediterranean coast, thus firmly establishing their unrivaled hegemony. Yet any hopes of immediately occupying these regions quickly vanished because of calamities and miscalculations in the early 120s BCE. Although nomadic incursions ravaged the Iranian plateau in the east throughout the 120s BCE, in the west Phraates II’s sudden release of Demetrius to contest the Seleucid throne in Syria before the death of Antiochus became a political debacle that hindered Parthian influence in the region. Despite the arguments of recent scholarship, Phraates’ decision to release Demetrius was shortsighted and haphazard, and Demetrius never served in Syria as a Parthian vassal. This article is a reevaluation of the western policy of the Parthians in the early 120s BCE and the actions of Demetrius during his second reign concerning the Parthians.

Base Shear Struktur Beton Bertulang Yang Menggunakan Base Isolator Akibat Beban Gempa Dengan Menggunakan Etabs

The sudden release of energy within earth creates seismic waves on earth’s surface that is earthquake. This research was carried out using a base isolator type of HDR with Certification Number MVBR-0516 (XO.3R) to reduce base shear, displacement and internal forces acting on the structure. This study uses time history analysis method with some earthquake loads in the form of acceleration acceleration. The objectives of the study were to determine the base shear of a reinforced concrete structure building using a base isolator and without using a base insulator. The results of this study indicate the use of base insulators reduces base shear by about 20% -67% and 14% -70.5% for earthquakes in the x direction to the east and west. Meanwhile, in the y direction earthquake, it was around 43% -70% and 43% -62% to the south and north

Acoustic Emission of Metallic Specimen with Surface Defect During Fatigue Crack Growth

Acoustic emission is defined as the phenomena whereby transient elastic waves are generated by the rapid release of localized sources within a material. During fatigue crack growth, the formation of new crack surfaces is associated with a sudden release of energy, which constitutes acoustic sources for acoustic emission. This paper investigates the acoustic emission signature arising from fatigue test of a metallic specimen under tensile fatigue test. In this experimental study, dog-bone aluminium alloy specimen with a surface defect was fatigued to failure. It is found that the acoustic emission characteristics are different during the propagation of surface crack, because the source is changing. The results provide a useful guide in identifying source origin based on the characteristics of the acoustic emission waveform.