Reversible Action Research Articles

Influence of Initial Position of Sliding Device on Premixed Methane/air Gas Explosion Flame at Driving Face in Coal Mine

ABSTRACT Many gas explosion accidents show that gas explosion can easily cause a large number of casualties and huge property losses in coal mines. Therefore, the sliding device is established to study its explosion suppression effect, and the influence of the initial position of the sliding device on the explosion is analyzed. The results show that when the sliding device is close to the ignition source, due to the strong reverse action of the spring, the sliding baffle has a reverse secondary acceleration movement, thus forming a crescent-shaped forward compression flame, forming a reverse acceleration inhibition effect and rapidly extinguishing, and this rapid reverse movement is the key technology of accelerating chain breaking and wall collision effect in methanation reaction. Generally speaking, the sliding device can effectively control the overpressure and can make the flame extinguish quickly. At the same time, the possibility of secondary fire and explosion caused by the spread of explosion in other areas is prevented. Thus, the sliding device has a good effect of explosion-proof and suppression in coal mines.

Experimental behaviour of non-seismical RWS connections with perforated beams under cyclic actions

The use of perforated (in particular cellular and castellated) beams has become widespread as their manufacturing processes keep minimising wasted material and has become cost-effective by reducing self-weight of steel structures, while allowing for larger clear spans. Although their behaviour to time-invariant vertical loads has been extensively investigated and validated in laboratory setups, their response to reversible actions has not been explored to the same extent. This paper presents results of cyclic load tests of beam-column reduced web section (RWS) connections, considering setups representative of what is observed in low-rise buildings in the UK; a region with sparse seismicity. Results show that RWS connections on these frames can achieve stable hysteresis loops without significant strength degradation, due to the simultaneous occurrence of yielding of the critical cross-section and development of a Vierendeel mechanism on the edges of the perforations (web openings). Also, inelastic action is mostly observed within the beam, thus being successful in protecting the beam-column connection. Performance particularly exceeds what is observed for a benchmarking RBS connection styled according to the same underlying assumptions, hinting that RWS connections could be a more suitable solution for structural retrofitting in regions where seismicity is sparse.

Reversing the Humidity Response of MoS2- and WS2-Based Sensors Using Transition-Metal Salts.

Two-dimensional materials, such as transition-metal dichalcogenides (TMDs), are attractive candidates for sensing applications due to their high surface-to-volume ratio, chemically active edges, and good electrical properties. However, their electrical response to humidity is still under debate and experimental reports remain inconclusive. For instance, in different studies, the impedance of MoS2-based sensors has been found to either decrease or increase with increasing humidity, compromising the use of MoS2 for humidity sensing. In this work, we focus on understanding the interaction between water and TMDs. We fabricated and studied humidity sensors based on MoS2 and WS2 coated with copper chloride and silver nitrate. The devices exhibited high chemical stability and excellent humidity sensing performance in relative humidity between 4 and 80%, with response and recovery times of 2 and 40 s, respectively. We have systematically investigated the humidity response of the materials as a function of the type and amount of induced metal salt and observed the reverse action of sensing mechanisms. This phenomenon is explained based on a detailed structural analysis of the samples considering the Grotthuss mechanism in the presence of charge trapping, which was represented by an appropriate lumped-element model. Our findings open up a possibility to tune the electrical response in a facile manner and without compromising the high performance of the sensor. They offer an insight into the time-dependent performance and aging of the TMD-based sensing devices.

Reverse action hydraulic hammer control circuit

The paper describes the mode of functioning of the reverse action hydraulic hammer with piston driven in the positive direction by the energy of air compressed during cocking of the piston by the hydraulic drive. The authors discuss various control circuits of such hydraulic hammers, control sensors, capabilities of the circuits, as well as their advantages and disadvantages.

A p97/Valosin-Containing Protein Inhibitor Drug CB-5083 Has a Potent but Reversible Off-Target Effect on Phosphodiesterase-6.

CB-5083 is an inhibitor of p97/valosin-containing protein (VCP), for which phase I trials for cancer were terminated because of adverse effects on vision, such as photophobia and dyschromatopsia. Lower dose CB-5083 could combat inclusion body myopathy with early-onset Paget disease and frontotemporal dementia or multisystem proteinopathy caused by gain-of-function mutations in VCP. We hypothesized that the visual impairment in the cancer trial was due to CB-5083's inhibition of phosphodiesterase (PDE)-6, which mediates signal transduction in photoreceptors. To test our hypothesis, we used in vivo and ex vivo electroretinography (ERG) in mice and a PDE6 activity assay of bovine rod outer segment (ROS) extracts. Additionally, histology and optical coherence tomography were used to assess CB-5083's long-term ocular toxicity. A single administration of CB-5083 led to robust ERG signal deterioration, specifically in photoresponse kinetics. Similar recordings with known PDE inhibitors sildenafil, tadalafil, vardenafil, and zaprinast showed that only vardenafil had as strong an effect on the ERG signal in vivo as did CB-5083. In the biochemical assay, CB-5083 inhibited PDE6 activity with a potency higher than sildenafil but lower than that of vardenafil. Ex vivo ERG revealed a PDE6 inhibition constant of 80 nM for CB-5083, which is 7-fold smaller than that for sildenafil. Finally, we showed that the inhibitory effect of CB-5083 on visual function is reversible, and its chronic administration does not cause permanent retinal anomalies in aged VCP-disease model mice. Our results warrant re-evaluation of CB-5083 as a clinical therapeutic agent. We recommend preclinical ERG recordings as a routine drug safety screen. SIGNIFICANCE STATEMENT: This report supports the use of a valosin-containing protein (VCP) inhibitor drug, CB-5083, for the treatment of neuromuscular VCP disease despite CB-5083's initial clinical failure for cancer treatment due to side effects on vision. The data show that CB-5083 displays a dose-dependent but reversible inhibitory action on phosphodiesterase-6, an essential enzyme in retinal photoreceptor function, but no long-term consequences on retinal function or structure.

Bi-state switch based on two-dimensional guided-mode resonance

In this paper, a bi-state (on/off) switch is proposed utilizing a two-dimensional, all-dielectric periodic guided-mode resonance (GMR) structure. Employing a conceptual MEMS mechanism, switching is performed by modifying the Fourier series coefficients of the refractive index distribution. This switch operates in the visible region. In the ‘on’ state, the switch exhibits a narrow linewidth reflection resonance at λ = 541 nm; this resonance disappears in the ‘off’ state. In fact, in the ‘off’ state, the condition for supporting a GMR is lost. This element exhibits a reversible switching action and can be a potential candidate for narrowband optical switches, light modulators, and laser systems.

Structural and stability analysis of Na4Mn4Ti5O18 for energy storage application

We report a single-phase Na4Mn4Ti5O18 oxide prepared via ceramic processing route. Rietveld refinement of X-ray diffraction results indicated orthorhombic unit cell indexed with Pbam space group. Further, structural analysis using X-ray diffraction, transmission electron microscopy and Raman spectroscopy suggested crystal structure comprising two distinct tunnel pathway, polygonal and Z-shaped tunnels with void dimensions ~ 4.07 A and ~ 3.01 A, respectively, suitable for reversible cation transport desirable for energy storage applications. X-ray photoelectron spectroscopy confirmed presence of Mn2+, Mn3+, Mn4+ and Ti4+ in Na4Mn4Ti5O18. Surface morphology in field emission scanning electron microscopy exhibited inhomogenously distributed micro-bead grains separated by well-defined boundaries in good agreement with complex impedance spectrum results. Estimated dc conductivity and surface area is ~ 1.745 × 10− 6 S cm− 1 and ~ 0.66 m2g− 1 respectively. Electrochemical energy storage performance with cell; Na || 1 M NaFSI (EC : DMC, 1:1 v/v%) || Na4Mn4Ti5O18 in voltage range 2.0–3.8 V indicated reversible redox action. Identical cell in voltage range 0.01–2.5 V, exhibited pseudo-capacitive behaviour. Results suggest energy storage possibility with Na4Mn4Ti5O18 electrode.

Updates on the molecular mechanisms of aspirin in the prevention of colorectal cancer: Review.

Colorectal cancer is one of the commonest malignancies worldwide. The estimated lifetime risk of the disease is about 5% with an incidence of one million new cases and 600,000 deaths worldwide every year. It is estimated that in 2019, approximately 134,490 new cases of colorectal cancer will be diagnosed with 49,190 mortalities. Though the disease is regarded as a disorder of the more developed world, the occurrence is steadily increasing in many developing countries. Since chronic inflammation is a known aggravating risk factor for colorectal cancer, anti-inflammatory agents such as aspirin have been used to prevent the development of colorectal cancer and related mortality. The potential mechanisms for the effect of aspirin in the prevention of colorectal cancer have been proposed and broadly classified as cyclooxygenase (COX) dependent and COX-independent. Some of the primary effectors of COX-dependent mechanisms in carcinogenesis are likely to be prostaglandins. In contrast to the reversible action of other nonsteroidal anti-inflammatory drugs, aspirin is known to irreversibly inactivate COX enzymes to suppress production of prostaglandins. COX-independent mechanisms of anticancer effects of aspirin include down-regulation of nuclear factor kappa B activity and Akt activation, modulation of Bcl-2 and Bax family proteins, suppression of vascular endothelial growth factor, induction of apoptosis, disruption of DNA repair mechanisms, and induction of spermidine/spermine N1-acetyltransferase that modulates polyamine catabolism.

СТОЙКОСТЬ УГЛЕПЛАСТИКОВ И СТЕКЛОПЛАСТИКОВ НА ОСНОВЕ РАСПЛАВНЫХ СВЯЗУЮЩИХ К ВОЗДЕЙСТВИЮ УМЕРЕННО ХОЛОДНОГО И УМЕРЕННО ТЕПЛОГО КЛИМАТА

In this work has been investigated the climatic resistance of carbon and fiberglass polymers for aviation purposes based on solvent-free binders VST-1208, VSE-1212, VSR-3M after 3 years of exposure of these materials in the moderate cold climate of Moscow and the moderate warm climate of Gelendzhik. The effect of destruction, post curing, plasticization of binders on the compressive and flexural strengths of carbon plastics VKU-27L, VKU-39, VKU-46 and fiberglass plastics VPS-47/7781, VPS-48/778 was determined using the methods of profilometry, moisture transfer and dynamic mechanical analysis. It is shown that while determining the state of PCM after climatic exposure, it is necessary to take into account the effects of the reversible plasticizing action of moisture. A comparison is made of the climatic resistance of the investigated materials.

ТЕОРЕТИЧНІ ОСНОВИ МЕХАНІЗМІВ СТРУКТУРУВАННЯ ПІДСИСТЕМИ ПЛАНУВАННЯ І КОНТРОЛЮ ОПЕРАЦІЙНОЇ СИСТЕМИ ОРГАНІЗАЦІЇ

The article discusses the theoretical foundations of the structuring mechanism for the planning and control subsystem of the organization's operating system. In the operating management system, the system acts as the object of management, planning and control subsystem is the subject of management. The author's algorithm for constructing of mechanism planning and control subsystem (PCS) of the operating system (OS) of the organization is proposed. This mechanism represents a scientifically grounded trajectory of its development. The core of the mechanism for constructing the PCS OS of the organization is the PCS reengineering model on the basis of which the structuring of the processes occurring in the PCS OS is carried out. The PCS OS reengineering model is considered as the subordination of three components to be studied in the organization: formation of the OS development concept; diagnostics of the state of the PCS OS; simulation of PCS OS. Formation of the OS development concept is the definition of the main parameters of the OS PCS activity, but their formulation is an important role in the further development of the OS PCS. Diagnostics of the organization's PCS OS operation includes the determination of evaluative features, the choice of methods for their measurement and characterization of these features according to certain principles, assessment of the identified deviations from standard, generally accepted values. Reengineering PCS OS is a process of identifying management tasks that are not at all solved in PCS OS or are being solved poorly. The PCS OS model of an organization based on reengineering consists of several blocks. The input receives information about the conceptual (methodological) parameters of the OS, there are the goal, the strategy and the policy for the development of the OS, as well as promising programs for the development of the OS. These parameters are the vision of the operational management and top management of the organization of the current market situation, demand on products and other important indicators. The OS development program can contain both general and specific areas of activity. The final stage of structuring is the formation of functional tasks for managing the OS PCS. The stages of implementation of the PCS reengineering model in the OS are analyzed as well as indicators for assessing the implementation results, the assessment algorithm, possible scenarios and reverse actions based on the results of implementation are considered.

TNF-α–mediated reduction in inhibitory neurotransmission precedes sporadic Alzheimer’s disease pathology in young Trem2R47H rats

Alzheimer’s disease (AD) is a neurodegenerative dementia associated with deposition of amyloid plaques and neurofibrillary tangles, formed by amyloid β (Aβ) peptides and phosphor-tau, respectively, in the central nervous system. Approximately 2% of AD cases are due to familial AD (FAD); ∼98% of cases are sporadic AD (SAD). Animal models with FAD are commonly used to study SAD pathogenesis. Because mechanisms leading to FAD and SAD may be distinct, to study SAD pathogenesis, we generated Trem2R47H knock-in rats, which carry the SAD risk factor p.R47H variant of the microglia gene triggering receptor expressed on myeloid cells 2 (TREM2). Trem2R47H rats produce human-Aβ from a humanized-App rat allele because human-Aβ is more toxic than rodent-Aβ and the pathogenic role of the p.R47H TREM2 variant has been linked to human-Aβ–clearing deficits. Using periadolescent Trem2R47H rats, we previously demonstrated that supraphysiological tumor necrosis factor-α (TNF-α) boosts glutamatergic transmission, which is excitatory, and suppresses long-term potentiation, a surrogate of learning and memory. Here, we tested the effect of the p.R47H variant on the inhibitory neurotransmitter γ-aminobutyric acid. We report that GABAergic transmission is decreased in Trem2R47H/R47H rats. This decrease is due to acute and reversible action of TNF-α and is not associated with increased human-Aβ levels and AD pathology. Thus, the p.R47H variant changes the excitatory/inhibitory balance, favoring excitation. This imbalance could potentiate glutamate excitotoxicity and contribute to neuronal dysfunction, enhanced neuronal death, and neurodegeneration. Future studies will determine whether this imbalance represents an early, Aβ-independent pathway leading to dementia and may reveal the AD-modifying therapeutic potential of TNF-α inhibition in the central nervous system.

An experimental study to evaluate the antidotal activity of Neeli Moola (Indigofera tinctoria) Kalka w.s.r to haematological parameters in Vatsanabha (Aconitum ferox ) induced toxicity

Background: Vatsanabha is a potent cardiac poison comes under the category of Mahavisha with its main active principles aconitine, picraconine and pseudaconine. In the literatures there are descriptions about toxicants and in some traditional Malayalam textbooks antidotes has been explained under the concept “Prathyoushadha”. Neeli Moola has been mentioned as a Prathyoushadha for Vatsanabha poisoning in a renowned textbook „Visha Vaidya Jyotsnika‟. Hence to evaluate the antidotal activity in Vatsanabha poisoning, Neeli Moola Kalka has been used and the haematological parameters were analyzed to screen the results. Methods: Wistar strain albino rats were used in this study which were divided into 3 groups, normal control, toxic control and the test drug group. The duration of the study was 28 days .The data generated was mentioned as Mean±SEM. Difference among the groups was assessed by employing one way ANOVA followed by Dunnet‟s mul tiple „t‟ test. Results: Reversible action has been observed after the administration of Neeli Moola Kalka in the hematological parameters which has shown toxicity changes due to administration of Vatsanabha. Conclusion: Neeli Moola Kalka is having mild to moderate antidote effect in Vatsanbha induced toxicity.

METHODICAL SUPPORT OF ASSESSMENT OF THE DEVELOPMENT OF ECONOMIC SECURITY OF THE REGION

The subject of research is actual problems of diagnostics of threats and risks of regional development, factors of economic safety, methodological support of its estimation. The aim is to formulate a methodological framework for assessing the economic security of the regions development. The formation of the research methodology is carried out on the basis of theoretical and methodological platform for the development of rating method for assessing the economic security of the region. The use of the matrix method for describing the initial state of the system has been justified; the method of normalized values has been used for bringing various indices. Factors influencing the level of investment activity and economic security of the region have been identified. All factors that change the level of economic security are divided into four groups depending on the macroeconomic indicators, the level of which they take into account. It is proposed to divide them into two groups – direct action factors that increase the level of safety and reverse action factors that reduce it. Indicators characterizing the economic development of the region have been grouped by factors of economic security. For each group, the significance of the impact of indicators of individual groups for evaluation of the economic security of the region development has been determined. To estimate the economic security of the regions' development, it was proposed to use an integral indicator based on the state of general economic development, investment activity in the region and demographic indicators of economic development. Depending on the influence of individual factors, the rank of each region is determined first for each group of factors, and then the integral. According to the results of the assessment of the economic security of regions' development by individual groups of factors and the calculated integral indicator, the place of each region has been determined by the level of economic security. The result of the study is classification of the regions according to certain criteria on the basis of the integral index of economic security of the regions' development, which will allow not only to compare the level of economic security, but also to formulate a nationally balanced regional development strategy and identify priority investment areas.

Heat transfer in a cylindrical crucible with liquid metal under continuous and reverse action of traveling and rotating magnetic fields

Heat transfer in a cylindrical crucible with liquid metal under continuous and reverse action of traveling and rotating magnetic fields

Analytical models for reverse arch and compressive arch action in horizontally restrained unbonded prestressed RC beam-column sub-assemblages

This paper presents the analytical models to predict the reverse arch action (RAA) and the compressive arch action (CAA) of unbonded prestressed reinforced concrete (UPRC) beam-column sub-assemblages under column removal scenarios. In the models, the realistic stress–strain model for concrete is applied to calculate the compression force sustained by concrete, instead of the equivalent rectangular concrete stress block. A linear variation of the strains for concrete and steel reinforcement along the beam length is assumed. Moreover, a notional eccentricity of eccentric force imposing on beam section is introduced in the RAA model to determine its bending moment. Comparisons between FEM’s and analytical results indicate that reasonable accuracy can be obtained in predicting not only the inverted camber and the RAA capacity of the sub-assemblages by the RAA model, but also the CAA capacity and the horizontal reaction force through the CAA model. Furthermore, the effects of effective prestress on the CAA of the sub-assemblages are investigated. Finally, through a contrastive analysis, it can be concluded that the increase of effective prestress is beneficial to the enhancement of CAA capacity to mitigate structural progressive collapse but worse to the ductility of beam section.

Investigating Reversibility of Steps in Petri Nets

In reversible computations one is interested in the development of mechanisms allowing to undo the effects of executed actions. The past research has been concerned mainly with reversing single actions. In this paper, we consider the problem of reversing the effect of the execution of groups of actions (steps). Using Petri nets as a system model, we introduce concepts related to this new scenario, generalising notions used in the single action case. We then present properties arising when reverse actions are allowed in place/transition nets (PT-nets). We obtain both positive and negative results, showing that allowing steps makes reversibility more problematic than in the interleaving/sequential case. In particular, we demonstrate that there is a crucial difference between reversing steps which are sets and those which are true multisets. Moreover, in contrast to sequential semantics, splitting reverses does not lead to a general method for reversing bounded PT-nets. We then show that a suitable solution can be obtained by combining split reverses with weighted read arcs.

Tribological tests of the improved piston mechanism of the axial piston hydraulic machine

Axial-piston hydraulic swash plate machines are widely applied in positive displacement hydraulic drives of various purposes. Such drives are highly energy-intensive and have a relatively small control range due to the presence of a large dead-band, which limits their use in reverse action systems. To reduce the dead-band, an improved axial-piston hydraulic swash plate machine was designed. The decrease of the dead-band is achieved by reducing the friction forces in the piston mechanism. This article presents the results of comparative tribological tests of a standard and improved piston mechanisms. The experimental research was conducted in terms of reducing the friction forces in the piston mechanism and their effect on the moment of starting of the hydraulic machine. It was revealed that the use of the improved piston mechanism allows to increase the useful force of the piston up to 20 % in the motor mode and to reduce the dead band by 1.6 times when switching to the pump mode.

HAPPINESS FACING TO THE PERFIDIOUS AND INVISIBLE CHALLENGE OF COVID-19

In this study we are dealing with a new aspect of the problem in discussion that is the pursuing of Happiness, supported by institutions and regulations in the domain, but in moments of disturbances, in moments of crisis. We need to have goals, actions to be accomplished, in order to achieve the desired state of satisfaction or Happiness that anyone can have. We are in the presence of a double determination: the first one is represented by the material, especially money background, influencing the life and activities of households and entities and, the second one is represented by the reverse action that is of Happiness affecting the management and the activities of individuals, households and firms/organizations. The survey of the literature in the field, data from the World Health Organization, from the national authorities, analyses of the specialists in healthcare and economics, reports of the people in difficult health and economic situations are used in order to be able to synthesize the situation at this moment and possible forecasts regarding medical healing and economic recovery of the countries. Nothing is hard to manage, if you have knowledge, required abilities/skills to anticipate challenges or to make fast and right decisions, altogether at Micro and Macro-levels, in the benefit of all parts involved in. The huge interest is to reestablish the economies, mental health of people, i.e. the elements of a functional economic infrastructure.

PdpaMn inhibits fatty acid synthase-mediated glycolysis by down-regulating PI3K/Akt signaling pathway in breast cancer.

Novel manganese complex, PdpaMn ([(Pdpa)MnCl2]), was developed to induce apoptosis in breast cancer cells. The impact of phosphoinositide-(3)-kinase pathway onto fatty acid synthase (FASN) has an effect on cellular metabolism in breast cancer. However, reverse actions from FASN towards PI3K/Akt are still indefinable. Perhaps, loss of FASN could regulate glycolysis. Previously we established that PdpaMn inhibits FASN and involve in mitochondrial function. This study investigated the activity of PdpaMn on glycolysis and its mechanism. PdpaMn was used to suppress FASN expression in tumor. Expression of ATP and lactic acid level was measured to investigate the glycolysis variance in cells and animals. MCF-7 and 4T1 cells were treated with G28UCM, an inhibitor of FASN and PdpaMn, western blotting to detect PI3K/Akt signaling pathway. The capacity of proliferation was investigated by western blotting and immunohistochemistry. PdpaMn selectively inhibits cancer cells and tumor growth but also block FASN expression and suppresses the content of free fatty acid. Lactate dehydrogenase (LDHA) protein level was down-regulated as G28UCM and PdpaMn inhibited FASN, glucose transporter (Glut1), and pyruvate kinase (PKM2) proteins level were not affected. PI3K, p-Akt in the experimental group evidently declined compared to the control group. Proliferation was suppressed in FASN-arbitrated glycolysis. Our study supports the hypothesis that loss of FASN by PdpaMn suppressed glycolysis via down-regulating PI3K/Akt signaling pathway revealing the direct link between FASN and glycolysis. The results have paved the way to unravel the mechanisms of FASN and mitochondrial will be useful for designing novel co-targeting strategies for breast cancer.

Folium Sennae and emodin reverse airway smooth muscle contraction.

The objective of this project was to find a bronchodilatory compound from herbs and clarify the mechanism. We found that the ethanol extract of Folium Sennae (EEFS) can relax airway smooth muscle (ASM). EEFS inhibited ASM contraction, induced by acetylcholine, in mouse tracheal rings and lung slices. High-performance liquid chromatography assay showed that EEFS contained emodin. Emodin had a similar reversal action. Acetylcholine-evoked contraction was also partially reduced by nifedipine (a selective inhibitor of L-type voltage-dependent Ca2+ channels, LVDCCs), YM-58483 (a selective inhibitor of store-operated Ca2+ entry, SOCE), as well as Y-27632 (an inhibitor of Rho-associated protein kinase). In addition, LVDCC- and SOCE-mediated currents and cytosolic Ca2+ elevations were inhibited by emodin. Emodin reversed acetylcholine-caused increases in phosphorylation of myosin phosphatase target subunit 1. Furthermore, emodin, in vivo, inhibited acetylcholine-induced respiratory system resistance in mice. These results indicate that EEFS-induced relaxation results from emodin inhibiting LVDCC, SOCE, and Ca2+ sensitization. These findings suggest that Folium Sennae and emodin may be new sources of bronchodilators.