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The global spread of coronavirus illness (COVID-19) has been the most serious public health hazard to human life since 2019. For approximately three years, the COVID-19 pandemic has spread over the world, causing individuals to suffer not only from the virus's anguish but also from the consequences once they recover. Symptoms such as pneumonia, hypoxia, and severe respiratory distress emerge as the condition advances. The impact of gender, age, and genetic differences on the outcome of COVID-19 symptoms has piqued the interest of researchers in this field. Scientists from all over the world have established that the sequel is related to the epigenetic mechanism. As a result, the author examines the epigenetic effect on COVID-19 using a literature review method.

This study aimed to examine whether the administration of losartan can prevent acute elevation of pulmonary arterial pressure (AEPAP) induced by endovascular ethanol injection and to assess its related mechanisms. Male swine were selected and performed with absolute ethanol endovascular injection. Saline was used as the negative control. Losartan was administered preoperatively. Pulmonary arterial pressure (PAP), femoral arterial pressure (FAP) and heart rate (HR) were monitored during operations. Venous plasma and pulmonary artery (PA) tissue were harvested for analyses. Protein level was detected by Western blotting and ELISA, whereas qRT-PCR was used in mRNA detection. HE staining and immunohistochemistry were conducted to evaluate histopathology. Ethanol injection elevated PAP in swine. The concentration of RAS ligands was elevated in plasma (all P 0.0001) but not in PA. The level of oxidative stress increased in both plasma and PA. MRNA level of AT1R (P 0.01, 95% CI: 0.251-1.006), not AT2R increased in PA. Losartan failed to inhibit AEPAP after all sessions of ethanol injection, and partially reversed the ethanol-induced PA remodeling. The P38 MAPK was activated after ethanol injection and could be inhibited by losartan (P 0.01, 95% CI: -0.391 to -0.164). Ethanol also promoted the translocation of the P40-PHOX/P47-PHOX/P67-PHOX complex and the activation of NOX, which was independent from RAS. Endovascular ethanol injection can induce AEPAP mainly by activating RAS and P38 MAPK signaling. Losartan can partially prevent AEPAP and vascular remodeling owing to the promotion of NOX activity by ethanol. Mechanism diagram of endovascular ethanol injection-induced acute elevation of pulmonary arterial pressure (AEPAP) partially prevented by losartan. RAS: Renin-angiotensin system; AGT: angiotensinogen; Ang I: angiotensin I; ACE: angiotensin I converting enzyme; Ang II: angiotensin II. AT1R: angiotensin II type 1 receptor. NOX2: NADPH oxidase 2. PA: pulmonary artery.

The goaf is the main site of gas explosions in coal mines. A large number of accidents indicate that the occurrence of gas explosion in the goaf is related to the deformation and fracture of the goaf roof. An experimental system was constructed to study the instantaneous discharge characteristics and its ignition mechanism caused by rock damage. The research results reveal that different rocks produce avalanche-like dust clouds ejected outward during the fracture process, and the generation process takes an extremely short time. This dust cloud is not caused by rock fragments heated to incandescence because of friction. The electric sparks produced in the process of rock rupture and the appearance of instantaneous discharge are related not only to the quartz content of the rock, but also to the compressive strength of the rock. The piezoelectric effect of the rock becomes the key factor for the strength or the generation of an electric spark. The instantaneous discharge leaded to the collision of high-energy electrons released during the fracture process with air molecules, ionising, and breaking down the air. When the surrounding medium is gas air within the explosion limit, ionisation is formed and causes gas explosions.

Liquid flow is subject to head loss because of viscous force, surface tension, friction force, and so on. Part of the energy is irreversibly converted into heat, which then dissipates into the environment. Head loss intensifies in the turbulent state. At present, few studies explore the law of head loss caused by secondary flow, cavitation intensity, and turbulence intensity. In this study, the head losses in different sections of a jet pump were studied by controlling the cavitation number σ, the secondary flow rate

Background/Objectives: To investigate the effects of axial elongation on ganglion cell complex (GCC) thickness and retinal capillary density (CD) in the circular region (12 mm diameter) using wide-field swept-source optical coherence tomography angiography. Subjects/Methods: This retrospective and cross-sectional study included 506 eyes. Fovea-centred 15 × 12 mm² scans were acquired to measure the subregional GCC thickness and CD in the whole retina, superficial capillary plexus (SCP) and deep capillary plexus (DCP) among three groups: normal controls, high myopia (HM) eyes with an axial length (AL) 28 mm. The magnitude of GCC thickness and retinal CD changes with axial elongation was estimated using multivariable linear regression models. Results: The GCC thickness and retinal CD in HM eyes with an AL >28 mm were lesser than those in the other two groups in most regions (P

Background: Demethoxycurcumin (DMC), a natural derivative of curcumin, has anti-inflammatory activities. However, the mechanism has not been fully elucidated. Objective: The aim of the current study was to investigate the role of DMC on NLRP3 inflammasome priming. Methods: Protein expression was quantified by western blotting. Inflammatory cytokines were measured by ELISA. Autophagosomes were evaluated by transmission electron microscopy. Results: DMC inhibited LPS-stimulated NLRP3, pro-caspase-1, and pro-IL-1β expression. Meanwhile, DMC diminished NLRP3-dependent IL-1β maturation, caspase-1 activation, IL-1β, and IL-18 production caused by LPS plus ATP. Moreover, DMC induced autophagy and autophagy inhibitor 3-MA abrogated the role of DMC on NLRP3 inflammasome priming and subsequent activation. DMC also inhibited LPS-stimulated phosphorylation and nuclear translocation of p65 NF-κB. Additionally, DMC significantly increased the PPARγ expression, and the effects of DMC in NF- κB inhibition, autophagy, and NLRP3 inflammasome priming were abrogated by specific PPARγ antagonist T0070907. Conclusion: The evidence presented here has confirmed that DMC increases PPARγ expression, resulting in autophagy and NF-κB inhibition, and subsequently inhibits LPS-induced NLRP3 inflammasome priming and subsequent activation.

The wetting properties of ALES (Ammonium lauryl ether sulfate), SLES (sodium lauryl ether sulfate), TD (dodecyl triethanolamine salfate) and SDS (sodium dodecyl sulfate) solutions and their adsorption capacities on coal dust surface were evaluated by surface tension, contact angle, sink time, wetting rate, and changes in the micromorphology and functional groups on coal surface. The results showed that the four surfactants share similar adhesion and spreading wettability, while they differ notably in immersion wetting. A water-surfactant-low rank coal (LRC) system was established using Materials Studio software and the Wender coal model; then quantum chemical calculations and molecular dynamics (MD) simulations were conducted. The results showed that ALES is of the widest relative concentration distribution range (25.25–60 Å), the largest overlap range (25 Å) and the largest diffusion coefficient (D = 0.318); NH4+ can easily penetrate the surfactant layer, which proves the strong modification ability of ALES to LRC. ALES/LRC/H2O has the lowest interaction energy and the most H-bonds, indicating that ALES is of a strong adsorption capacity. Based on the experimental data and simulation results, the integrated wettabilities of the four surfactants follow ALES＞SLES＞TD＞SDS, partially contributed by the hydrolytic cations and EO groups. This project was supported by the Key Program of the National Natural Science Foundation of China (Grant No. 52130411), the National Natural Science Foundation of China (Grant No. 51974299), and the Fundamental Research Funds for the Central Universities (2020CXNL10). Jian Gan was supported by the China Scholarship Council (Grant No. 202006420018).

Purpose: Here, we report our experience treating a patient with Maffucci syndrome and evaluate the outcomes resulting from surgical management combined with sclerotherapy in the treatment of head and neck venous malformations (VMs). A 19-years-old woman with multiple enchondromas and heterauxesis complained of masses in the oral cavity that had gradually increased in size and eventually affected her daily life. A tracheotomy was performed followed by traditional sclerotherapy to treat the oropharyngeal VMs. Next, we surgically excised the VMs of the oral cavity and maxillofacial skin. Results: Magnetic resonance imaging indicated that the oral VMs were nearly eradicated and the oropharyngeal VMs had stabilized. The patient’s appearance and normal maxillofacial region function were restored. Conclusion: In summary, local resection combined with sclerotherapy facilitated timely and efficient VMs removal from the head and neck region of a patient with Maffucci syndrome.

Existing studies of coal self-ignition and impact frictional sparks do not provide valid support for the analysis of ignition sources in all cases of methane explosions in the gob. In this paper, the explosion in the gob of the Renlou coal mine is used to investigate the piezoelectric effect and ignition characteristics of roof collapse in identifying a new ignition source of gas explosion. Experimental and theoretical analyses conclude that the piezoelectric effect is produced by quartz, which is the main constituent of the roof sandstone. During the loading process, the piezoelectric effect and compressive strength are key factors in the gathering of free charges on rock tips. During rupture, the rock tip retains a large number of charges, forming a ″point-surface″ effect, which triggers an electron avalanche accompanied by an orange-yellow spark lasting over 22 ms, far exceeding the ionization energy and ignition induction period of methane–air mixtures. The piezoelectric effect and compressive strength of the rock cause the generation of electrical sparks, which is the ignition source of the explosion in the gob of Renlou mine II7322.

Additive Manufacturing technology has aroused widespread attention for free designing and rapid prototyping. Selective Laser Melting technology is one of the metal additive manufacturing technologies, and it has become an important choice for precision manufacturing of metal parts with high performance and complex shape. In the process of selective laser melting, the accuracy and efficiency of laying powders directly affect the quality and time of parts printing. In order to realize laying powder accurately and efficiently in printing process, the mechanical mechanism and movement strategy of the powder laying device are studied in this paper. A powder laying mechanism with automatic leveling function is designed. On the premise of ensuring the powder laying accuracy, a variable position powder laying movement strategy is proposed to improve the powder laying efficiency The case analysis results show that the laying powder efficiency has been increased by 49.2%.