Structural implications of SARS-CoV-2 Surface Glycoprotein N501Y mutation within receptor-binding domain [499-505]–computational analysis of the most frequent Asn501 polar uncharged amino acid mutations

The aim of this study was to evaluate the impact of the most frequent Asn501 polar uncharged amino acid mutations upon important structural properties of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) Surface Glycoprotein RBD–hACE2 (human angiotensin-converting enzyme 2) heterodimer. Mutations N501Y, N501T and N501S were considered and their impact upon complex solubility, secondary motifs formation and intermolecular hydrogen bonding interface was analyzed. Results and findings are reported based on 50 ns run in Gromacs molecular dynamics simulation software. Special attention is paid on the biomechanical shifts in the receptor-binding domain (RBD) [499-505]: ProThrAsn(Tyr)GlyValGlyTyr, having substituted Asparagine to Tyrosine at position 501. The main findings indicate that the N501S mutation increases SARS-CoV-2 S-protein RBD–hACE2 solubility over N501T, N501 (wild type): (Formula presented.), (Formula presented.). The N501Y mutation shifts (Formula presented.) -helix S-protein RBD [366-370]: SerValLeuTyrAsn into π-helix for t > 38.5 ns. An S-protein RBD [503-505]: ValGlyTyr shift from (Formula presented.) -helix into a turn is observed due to the N501Y mutation in t > 33 ns. An empirical proof for the presence of a Y501-binding pocket, based on RBD [499-505]: PTYGVGY (Formula presented.) 's RMSF peak formation is presented. There is enhanced electrostatic interaction between Tyr505 (RBD) phenolic -OH group and Glu37 (hACE2) side chain oxygen atoms due to the N501Y mutation. The N501Y mutation shifts the (Formula presented.) hydrogen bond into permanent polar contact;(Formula presented.);(Formula presented.). © 2023 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.

Beyond Lyophilization

The company's Lyoguard trays are being used in the production of mAbs;diagnostics tests for COVID-19 virus or antibodies;and some of the key raw materials used in messenger RNA (mRNA) vaccines, including synthetic oligonucleotides, adjuvants, and lipid nanoparticles, he says. [...]it's a question of capacity. Another problem is the fact that lyophilization involves very slow cooling, at a rate of one degree Kelvin per second, says Bill Williams, a professor at the University of Texas and inventor of the thin-film freezing process, which he developed years ago at the Dow Chemical Co. TFF Pharma licensed his technology and commercialized it in 2019. Williams and his team, with corporate and US government funding, are now focusing on research designed to optimize use of thin-film freezing to improve the processing and delivery of biologics, including vaccines, along with the cold chain.

Research on the 6XS6 of the SARS-CoV-2 Spike Protein

The 6XS6 is the structure of the SARS-CoV-2 spike protein. The physiological role of the spike protein is relative to the respiratory syndrome coronavirus and has a stronger infect on the human body than the ancestor virus. The purification of the 6XS6 is in the homo sapiens cell by the affinity chromatography, PBS supplemented and Size Exclusion chromatography. At last, using the Cryo-Electron Microscopy to see the structure. This paper is using the D614G mutation to illustrate the structure of the 6XS6. The N-terminal domain and C-terminal domain of the 6XS6 protein are ALA27 and VAL1137. Furthermore, the mutation doesn't have the hydrogen bond because the Asp614 is substituted by the Gly614, and the molecule that interacts with the Ala 647 may occur. While the 6XS6 structure has lots of non-covalent and disulfide bonds. Comparing the structure of the 6XS6 and 6VXX, both are glycoproteins, have three monomers, have two subunits, and have the same category of expression and classification. The different conformations of the two structures can affect the binding ability with the ACE2. This paper can help the researchers to further understand the structure and function of the 6XS6 which can be used in future experiments. © 2023 SPIE.

Recent advances in the effect of ultrasound on the binding of protein−polyphenol complexes in foodstuff

Foodstuff is a complex system that consists of a variety of nutrients. Protein is the basis of human life and health, which is made up of amino acids combined in different proportional orders. Polyphenols are a class of small molecule active substances with strong pro-life health effects. It has been found that protein and polyphenols can be combined by covalent and non-covalent interactions to form complex delivery carriers. The interaction between the two can effectively improve the physiological activities of proteins and enhance the bio-accessibility of polyphenols. With the maturation of ultrasound technology, several studies have shown that ultrasound can promote the production of protein−polyphenol complexes. To promote the study of protein–polyphenol interactions in foodstuff by ultrasound technology, the preparation methods of protein−polyphenol complexes, the effects of ultrasound on complex generation, and analytical methods were systematically summarized based on an extensive literature review, and further research directions were proposed. It provides the reference for the ultrasound study of protein−polyphenol complexes.

Engineering Design of a Health Service Station Sewage Treatment Station under COVID-19 Epidemic

Health service station is a place in which close contacts with the COVID-19 and other key populations are centralized quarantined for medical observation.A newly built health service station is equipped with 4 700 beds and a supporting sewage treatment station with a designed treatment scale of2 200 m~3/d.The treatment process consists of enhanced biological treatment system,sewage virus disinfection and sterilization system,aerosol disinfection and sterilization system and sludge disinfection and sterilization system.After treatment,the effluent and waste gas can meet the limit specified in Discharge Standard of Water Pollutants for Medical Organization （GB 18466-2005）.The average COD,NH3-N and SS in effluent are 14.53 mg/L,1.26 mg/L and 9.11 mg/L,respectively,and the average concentrations of H2S,NH3 and odor at the outlet are 0.01 mg/L,0.8 mg/L and 6.3,respectively.The sludge is disinfected regularly and then transported outside for disposal.This project can provide reference for sewage treatment design of emergency medical temporary isolation and observation facility and cabin hospital.

Inhalation Pneumonitis Caused by Nebulized Hydrogen Peroxide.

Hydrogen peroxide is a chemical commonly used as a household antiseptic for cleaning and disinfecting. No cases of acute hydrogen peroxide inhalation-induced lung injury are previously described. We present a case of acute chemical pneumonitis caused by mixing hydrogen peroxide in a nighttime continuous positive airway pressure device's humidifier used for obstructive sleep apnea to prevent COVID-19 infection. The patient endorsed mixing hydrogen peroxide with distilled water in his nighttime continuous positive airway pressure device's humidifier at a ratio of 1:3-1:2 for the previous week before admission based on a friend's advice in preventing COVID-19. The presenting chest X-ray showed new multifocal consolidations with interstitial markings and alveolar edema throughout both lungs. Chest computed tomography (CT) imaging demonstrated multifocal, bilateral, hazy consolidations with increased interstitial markings and bilateral pleural effusions. The patient was subsequently initiated on systemic glucocorticoid therapy, significantly improving hypoxemia and dyspnea. Inhalation of hydrogen peroxide may produce acute pneumonitis distinct from what has been described previously with chronic inhalation. Given this case, systemic glucocorticoid therapy may be considered a viable treatment option for acute hydrogen peroxide-associated inhalation lung injury causing pneumonitis.

Rapid degradation of chloroquine derivatives in a novel advanced reduction process: role of intramolecular hydrogen bond in the formation of excited triplet state compound

The role of triplet excited state compounds (TESC) in contaminants degradation by advanced reduction processes (ARPs) is rarely reported. In this study, Salicylic acid derivatives (SAD, e.g. Salicylic Acid (SA) and Sulfosalicylic acid (SSA)) were applied in ultraviolet activated sulfite process (UV/Sulfite) to generate TESC and enhance the decomposition of chloroquine derivatives (CQD, antiviral drugs being used for treating COVID-19 infection, e.g. chloroquine phosphate (CP)). The results indicated that the pseudo 1st order rate constant of CP (kobs-CP) increased by 2.76 and 6.26 fold, which increased from 9.10 × 10–4 s–1 in UV/Sulfite process to 2.51 × 10–3 s–1, 5.72 × 10–3 s–1 in UV/Sulfite/SA and UV/Sulfite/SSA process respectively. Similar phenomena were observed in other CQDs. Transient absorption spectra demonstrated that both triplet excited state SAD (3SAD*) and hydrated electron (eaq–) were the reactive intermediates in UV/Sulfite/SAD process, and contribute to the abatement of CP. The enhancement of SAD on contaminants degradation in UV/Sulfite/SAD process could attribute to the strong acceleration of eaq– toward the formation of 3SAD* in its photosensitive process, where SAD with intramoleuclar hydrogen bond would not undergo a directly photoionization process after absorbing a photon but undergo intersystem crossing to transform into 3SAD* which was then ionized to eaq– by biphotonic process, and constitute a hydrated electrons mediated photosensitization cycle with the supplement of eaq– from UV/Sulfite process. The higher CP degradation rate in UV/Sulfite/SSA process than that in UV/Sulfite/SA process was ascribed to a higher second order rate constant of 3SSA* toward CP and a higher yield of 3SSA*, which resulted from its higher intramolecular hydrogen bond energy enhancing photosensitization and photoionization.

Hydrogen Bonding (Base Pairing) in Antiviral Activity.

Base pairing based on hydrogen bonding has, since its inception, been crucial in the antiviral activity of arabinosyladenine, 2'-deoxyuridines (i.e., IDU, TFT, BVDU), acyclic nucleoside analogues (i.e., acyclovir) and nucleoside reverse transcriptase inhibitors (NRTIs). Base pairing based on hydrogen bonding also plays a key role in the mechanism of action of various acyclic nucleoside phosphonates (ANPs) such as adefovir, tenofovir, cidofovir and O-DAPYs, thus explaining their activity against a wide array of DNA viruses (human hepatitis B virus (HBV), human immunodeficiency (HIV) and human herpes viruses (i.e., human cytomegalovirus)). Hydrogen bonding (base pairing) also seems to be involved in the inhibitory activity of Cf1743 (and its prodrug FV-100) against varicella-zoster virus (VZV) and in the activity of sofosbuvir against hepatitis C virus and that of remdesivir against SARS-CoV-2 (COVID-19). Hydrogen bonding (base pairing) may also explain the broad-spectrum antiviral effects of ribavirin and favipiravir. This may lead to lethal mutagenesis (error catastrophe), as has been demonstrated with molnutegravir in its activity against SARS-CoV-2.

Lactulose Works in the Large Bowel: But How Does It Improve Hepatic Encephalopathy in a Patient Without a Large Bowel?

Introduction: Lactulose is a non-absorbable disaccharide which acts in the large bowel, and is commonly used in the treatment of hepatic encephalopathy. We present an interesting case of altered mental status due to hepatic encephalopathy successfully managed with lactulose in a patient with history of total colectomy. Case Description/Methods: A 67-year-old male with non-alcoholic cirrhosis and inflammatory bowel disease (IBD) post total proctocolectomy with a continent ileostomy known as a Kock-pouch (K-pouch) presented to the hospital with flu like symptoms and altered mental status. He was subsequently found to be positive for COVID-19. At the time of initial evaluation, the patient was obtunded with an elevated ammonia level of 91 umol/L. Colorectal surgery was consulted as the patient was not able to empty his K-pouch. Recently, he complained of inability to catheterize and with bleeding from the stoma. Initial catheterization with a Water's tube yielded 400 cc of effluent. Nasogastric tube was placed through which he was receiving lactulose 30 mg q8 hours. The patient's mental status improved within 24 hours. The patient ultimately underwent flexible pouchoscopy with endoscopic dilation and placement of a 22 French mushroom catheter for decompression of the K-pouch. Discussion(s): Lactulose is a non-absorbable disaccharide composed of galactose and fructose. The small intestine does not have the enzymes required to breakdown lactulose so it reaches the large bowel in its original form. In the large bowel, it is metabolized by colonic bacteria into monosaccharides and then to volatile fatty acids, hydrogen and methane. Lactulose decreases both the production and absorption of ammonia mainly through the presence of gut bacteria. The question arises as to how lactulose decreased ammonia levels in this patient without a large bowel. One proposed mechanism is the translocation of bacteria normally found in the large bowel to the small intestine. Small Intestinal Bacterial Overgrowth (SIBO), is a condition causing an increased number of bacteria in the small intestine. Patients with IBD and structural abnormalities are at increased risk of developing SIBO. Lactulose is commonly used in the diagnosis through the administration of lactulose and subsequent measurements of hydrogen and methane gas in expired air. This condition, in our patient with history of ulcerative colitis and colectomy, is a proposed mechanism of the efficacy of lactulose in the treatment of hepatic encephalopathy.

An eco-friendly strategy for recovery of H-2-CH4-rich syngas, benzene-rich tar and carbon nanoparticles from surgical mask waste using an updraft gasifier system

The COVID-19 pandemic has created a new type of waste (surgical mask waste "WMs") that presents a major challenge now and in the future, given the strong possibilities of similar epidemics to reoccur. In order to find an effective industrial solution to the millions of WMs produced daily, this research aims to develop a new eco-friendly strategy to convert WMs into H-2-CH4-rich syngas, carbon nanoparticles (CNPs), and benzene-rich tar using an updraft gasifier system. The experiments started with the preparation of WM granules using shredding followed by granulation processes. Subsequently, the granules were processed in a lab-scale reactor with a capacity of 0.9-1 kg/h and consisted of a continuous WM feed system, a gasifier, a sampling system for syngas and tar, a ceramic filtration unit for separating the CNPs against the synthesis gas, and a burner. The gasification experiments were performed in ambient air with different air-fuel equivalence ratios (ER: 0.21, 0.25, and 0.29) and temperatures (700 degrees C, 800 degrees C, and 900 degrees C) to determine the optimal conditions that yield the maximum amount of H-2-CH4-rich syngas and CNPs with less impurities. The chemical composition and morphology of the obtained gasification products (syngas, tar, and CNPs) were observed using GC-FID, FTIR, and SEM. The results showed that the maximum production of syngas (4.29 +/- 0.16 kg/h with HHV of 3804 kJ/kg) and CNPs (0.14 +/- 0.011 kg/h) accompanied by a moderate tar rate (0.123 +/- 0.009 kg/h with HHV of 41,139.88 kJ/kg) could be obtained at 900 degrees C and ER = 0.29, while the highest H-2 (16.93 +/- 1.7 vol.%) and CH4 (10.44 +/- 0.85 vol.%) contents in syngas product were synthesized at 900 degrees C and ER = 0.19. Benzene and toluene were the major GC-FID compounds in the formulated tar product with abundance up to 25.6% and 11%, respectively. Meanwhile, gasification conditions of 900 degrees C and ER = 0.24 allowed the best morphology to be formulated for spherical-shaped CNPs with a diameter of less than 200 nm.

Towards a free energy-based elastic network model and its application to the SARS-COV2 binding to ACE2.

Classical normal mode analysis (cNMA) is a standard method for studying the equilibrium vibrations of macromolecules. A major limitation of cNMA is that it requires a cumbersome step of energy minimization that also alters the input structure significantly. Variants of normal mode analysis (NMA) exist that perform NMA directly on PDB structures without energy minimization, while maintaining most of the accuracy of cNMA. Spring-based NMA (sbNMA) is such a model. sbNMA uses an all-atom force field as cNMA does, which includes bonded terms such as bond stretching, bond angle bending, torsional, improper, and non-bonded terms such as van der Waals interactions. Electrostatics was not included in sbNMA because it introduced negative spring constants. In this work, we present a way to incorporate most of the electrostatic contributions in normal mode computations, which marks another significant step toward a free-energy-based elastic network model (ENM) for NMA. The vast majority of ENMs are entropy models. One significance of having a free energy-based model for NMA is that it allows one to study the contributions of both entropy and enthalpy. As an application, we apply this model to study the binding stability between SARS-COV2 and angiotensin converting enzyme 2 (or ACE2). Our results show that the stability at the binding interface is contributed nearly equally by hydrophobic interactions and hydrogen bonds.

Evaluating the effect of gargling with hydrogen peroxide and povidone-iodine on salivary viral load of SARS-CoV-2: A pilot randomized clinical trial.

Background and Aim: This study evaluates the salivary viral load of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in hospitalized patients and outpatients before and after gargling with 1% hydrogen peroxide and 0.25% povidone-iodine in comparison with normal saline. Patients and Methods: This clinical trial was conducted on 120 participants with laboratory-confirmed coronavirus disease 2019 (COVID-19) in two groups: outpatients (n = 60) and hospitalized patients (n = 60). In each group, the patients were randomly divided into three subgroups of 20 based on their given mouthwash for gargling (hydrogen peroxide, povidone-iodine, or normal saline). Two saliva samples were taken from each patient: the first one before gargling and the second one 10 minutes after gargling 10 ml of the respected mouthwashes for 30 seconds. The TaqMan real-time polymerase chain reaction (PCR) amplification of SARS-CoV-2 was used to measure the viral load. Results: Saliva samples from 46% of patients were positive for coronavirus before gargling the mouthwashes. The percentage of patients with an initial positive saliva sample was significantly higher in the outpatient group (83.3%) than in the hospitalized group (5.4%) (P = 0.01). According to the findings, gargling any mouthwash similar to saline did not reduce the viral load (P > 0.05). Conclusion: The saliva of COVID-19 patients in the initial stage of the disease was more likely to contain SARS-CoV-2 than the saliva of the hospitalized patients. Gargling hydrogen peroxide or povidone-iodine did not reduce the salivary SARS-CoV-2 viral load.

Analysis of the European Strategy for Hydrogen: A Comprehensive Review

This review focuses on analysing the strategy and aspirations of the European Union within the hydrogen sector. This aim is achieved through the examination of the European Parliament's hydrogen strategy, allowing for a study of actions and projects in hydrogen technologies. The Parliament's hydrogen strategy is the document that provides the guideline of how the EU intends to function in the hydrogen sector and manages to cover a wide range of topics, all of them significant to represent the entirety of the hydrogen sector. It touches on subjects such as hydrogen demand, infrastructure, research, and standards, among others. The review discusses also the aspect that the EU intends to be a leader in the hydrogen sector, including the large-scale industrialization of key elements such as electrolysers, and this purpose is corroborated by the large number of associations, strategies, plans, and projects that are being established and developed by the European Union. The most important conclusions to learn from this analysis are that hydrogen has many of the right characteristics to make it the key to decarbonisation, especially in hard-to-abate sectors, and that it is bound to be one of the main actors in the imminent green transition. Moreover, hydrogen seems to be having its breakthrough, and this field's development can have benefits not only from an environmental perspective but also from an economical one, enabling the way into the green transition and the fight against climate change.

Changes in the proteomics of exhaled breath condensate under the influence of inhaled hydrogen in patients with post-COVID syndrome.

Aim. To study the effect of inhalation therapy with an active hydrogen (AH) on the protein composition of exhaled breath condensate (EBC) in patients with post-COVID syndrome (PCS). Material and methods. This randomized controlled parallel prospective study included 60 patients after coronavirus disease 2019 (COVID-19) with PCS during the recovery period and clinical manifestations of chronic fatigue syndrome who received standard therapy according to the protocol for managing patients with chronic fatigue syndrome (CFS). The patients were divided into 2 groups: group 1 (main) - 30 people who received standard therapy and AH inhalations (SUISONIA, Japan) for 10 days, and group 2 (control) - 30 medical workers who received only standard therapy. Patients in both groups were comparable in sex and mean age. All participants in the study were sampled with EBC on days 1 and 10. Samples were subjected to tryptic digestion and high-performance liquid chromatography combined with tandem mass spectrometry analysis using a nanoflow chromatograph (Dionex 3000) in tandem with a high-resolution time-of-flight mass spectrometer (timsTOF Pro). Results. A total of 478 proteins and 1350 peptides were identified using high resolution mass spectrometry. The number of proteins in samples after AH therapy, on average, is 12% more than before treatment. An analysis of the distribution of proteins in different groups of patients showed that only half of these proteins (112) are common for all groups of samples and are detected in EBC before, after, and regardless of hydrogen therapy. In addition to the qualitative difference in the EBC protein compositions in different groups, quantitative changes in the concentration of 36 proteins (mainly structural and protective) were also revealed, which together made it possible to reliably distinguish between subgroups before and after treatment. It is worth noting that among these proteins there are participants of blood coagulation (alpha-1-antitrypsin), chemokine- and cytokine-mediated inflammation, and a number of signaling pathways (cytoplasmic actin 2), response to oxidative stress (thioredoxin), glycolysis (glyceraldehyde-3- phosphate dehydrogenase), etc. Conclusion. The use of hydrogen therapy can contribute to the switching of a number of physiological processes, which may affect the success of recovery in PCS patients. In particular, the obtained results indicate the activation of aerobic synthesis of adenosine triphosphate in mitochondria by hydrogen therapy, which correlates well with the decrease in the blood lactate level detected by laboratory studies. At the same time, this therapy can inhibit pro-inflammatory activity, negatively affecting the coagulation and signaling pathways of integrins and apoptosis, and, in addition, activate protective pathways, tricarboxylic acid cycle, FAS signaling, and purine metabolism, which may be essential for effective recovery after COVID-19.Copyright © 2023 Vserossiiskoe Obshchestvo Kardiologov. All rights reserved.

Coronavirus Disease (COVID-19) Possible Transmission Routes and Alleviation Strategies

Coronavirus disease is a contagious respiratory ailment that has spread significantly around the world. Most cases of COVID-19 are spread from person to person by coming into contact with respiratory droplets that are released when an infected person coughs or sneezes. In this manuscript, we have highlighted the possible transmission of COVID-19 through food, water, air and paper. In the case of food, we have extensively covered the transmission of COVID-19 through meat, frozen foods, food packaging and food market along with the incidences worldwide. In the nextsection, we have highlighted the different components of air which are responsible for the transmission and also covered its relation with PM 2.5 incidence. The SARS-CoV-2 was isolated from sewage water/wastewater of various countries namely the United States, India, Australia, Netherlands and France signifying that wastewater can be a mode of virus transmission. The paper circulation by the infected COVID-19 patients can also be a virus conveyance route. It can be concluded that SARS-CoV-2 can therefore be transmitted indirectly through food via the workers involved in food packing or food marts.By following general safety precautions (wearing masks, using hand sanitisers, cleaning and disinfecting contact surfaces, and avoiding close contact), heating and using chemicals like ethanol (67-71%), sodium hypochlorite (0.1%) and hydrogen peroxide (0.5%) on environmental surfaces, along with vaccination, it is possible to reduce the spread of the SARS-CoV-2 virus.Copyright © 2023 The International Journal of Pharmaceutical Research and Allied Sciences (IJPRAS).

Post-Covid mucormycosis presenting as retropharyngeal abscess: a rare case report

Background: Post-Covid retropharyngeal mucormycosis is a rare presentation, and no case has been reported in literature until date. Case presentation: A-32-year-old female post Covid presented to our OPD with history of dysphagia and with a history of steroid intake. Radiology confirmed it as retropharyngeal abscess. Endoscopic-guided aspiration was done. HPE (histopathological examination) revealed classic broad aseptate hyphae of mucormycosis. Patient was managed conservatively with broad-spectrum antifungal. Conclusion(s): Retropharyngeal mucormycosis is a rare entity in Covid era. Rapid diagnosis and management are needed to save life of an individual, or results could be fatal.Copyright © 2022, The Author(s).

Antiviral activitiy of curcumin, demethoxycurcumin, bisdemethoxycurcumin and cyclocurcumin compounds of Curcuma longa against NSP3 on SARS-CoV-2

SARS-CoV-2 genome encodes two large polyproteins (pp), pp1a and pp1ab which are cleaved and transformed into a mature form by a protease, non-structural protein 3 (NSP3). NSP3 is encoded by open reading frame (ORF) 1a/b. Curcuma longa (C. longa) or turmeric has been documented to have antiviral effects. The aim of this study was to assess the viral activities of C. longa against SARS-CoV-2 focusing on its potency to inhibit viral replication by targeting NSP3. PubChem databases were used to obtain the metabolic profile of C. longa. The compound's interaction with nucleocapsid was analyzed using molecular docking with Molegro Virtual Docker. Bioinformatics analysis based on rerank score presents all compounds of C. longa have higher binding affinity than the native ligand with cyclocurcumin as the lowest score (-128.38 kcal/mol). This anti-viral activity was hypothesized from the similarity of hydrogen bonds with amino acid residues Ser 128 and Asn 40 as key residues present in Ribavirin. This study reveals that C. longa is the potential to be developed as an antiviral agent through replication inhibition in SARS-CoV-2 targeting its replication mediated by NSP3.

Hydrogen sulfide: physiological roles and therapeutic implications against COVID-19.

The COVID-19 pandemic due to severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) poses a major menace to economic and public health worldwide. Angiotensin-converting enzyme 2 (ACE2) and transmembrane protease serine 2 (TMPRSS2) are two host proteins that play an essential function in the entry of SARS-COV-2 into host cells. Hydrogen sulfide (H2S), a new gasotransmitter, has been shown to protect the lungs from potential damage through its anti-inflammatory, antioxidant, antiviral, and anti-aging effects. It is well known that H2S is crucial in controlling the inflammatory reaction and the pro-inflammatory cytokine storm. Therefore, it has been suggested that some H2S donors may help treat acute lung inflammation. Furthermore, recent research illuminates a number of mechanisms of action that may explain the antiviral properties of H2S. Some early clinical findings indicate a negative correlation between endogenous H2S concentrations and COVID-19 intensity. Therefore, reusing H2S-releasing drugs could represent a curative option for COVID-19 therapy.

Production efficiency and economic benefit evaluation of biohydrogen produced using macroalgae as a biomass feedstock in Asian circular economies

This study uses three data envelopment analysis models to determine the production efficiency of biohydrogen which is produced from macroalgae and other sources by dark fermentation. The efficiency of macroalgae is greatest in batch mode for S. Japonica using a sDFMEC process at pH 5.3, 35 degrees C, 1 g COD/L and a hydrogen production rate (HPR) of 0.34 L/L/h. The highest efficiency is using an internal circulation batch reactor in continuous mode for beverage waste water. The HPR and substrate concentration are the most important factor of biohydrogen efficiency, and efficiency and temperature are the most important factors of HPR. Malaysia and India are the two economies that most benefit from increased production efficiency due to the use of macroalgae. Increasing biohydrogen yield efficiency will improve macroeconomic growth and establish a renewable hydrogen and biohydrogen industry, which is especially efficient related to the economic recovery during the COVID-19 pandemic. (c) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Modeling technology changes in air transport in the presence of a market shock: A passenger-based analysis

This paper proposes a formal model to assess the introduction of hydrogen technology in the air transport sector when the initial market is uncovered, a situation relevant to the current COVID-19 crisis. The "flight shame” movement causes some passengers to leave the market while allowing for some willingness-to-pay for cleaner technologies. Starting from a horizontally differentiated duopoly between airlines with old technology and an uncovered market, the introduction of hydrogen technology provides the opportunity for vertical differentiation in line with the increased environmental consciousness of passengers. The principal methodological novelties start from an uncovered market and combine horizontal and vertical differentiation. The main results are the airlines' optimal strategy sets and the adoption strategy dynamics with an increased valuation of quality by passengers. We justify a regulator's intervention and draw several potential policy implications from this dynamic, such as a minimum subsidy level and educational advertising. © 2022