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5-Hydroxymethylfurfural (HMF), which can be derived from lignocellulosic biomass, is an important platform molecule that can be used to produce valuable biofuels and polymeric materials. Electrochemical reduction of HMF is of great interest as it uses water as the hydrogen source and achieves desired reduction reactions at room temperature and ambient pressure. Hydrogenation and hydrogenolysis are two important reactions for reductive HMF conversion. Therefore, elucidating key characteristics of electrocatalysts that govern the selectivity for hydrogenation and hydrogenolysis is critical in rationally developing efficient and selective electrocatalysts. In this study, combined experimental and computational investigations are used to demonstrate how the adsorption energy of HMF on metal surfaces and the resulting changes in the intramolecular bond lengths of adsorbed HMF directly impact the reduction pathways of HMF. These results make it possible to rationally understand a general trend in the behaviors observed when using various metal electrodes for HMF reduction.

Hydrogenation and hydrogenolysis are two important reactions for electrochemical reductive valorization of biomass-derived oxygenates such as 5-hydroxymethylfurfural (HMF). In general, hydrogenolysis (which combines hydrogenation and deoxygenation) is more challenging than hydrogenation (which does not involve the cleavage of carbon-oxygen bonds). Thus, identifying factors and conditions that can promote hydrogenolysis is of great interest for reductive valorization of biomass-derived oxygenates. For the electrochemical reduction of HMF and its derivatives, it is known that aldehyde hydrogenation is not a part of aldehyde hydrogenolysis but rather a competing reaction; however, no atomic-level understanding is currently available to explain their electrochemical mechanistic differences. In this study, combined experimental and computational investigations were performed using Cu electrodes to elucidate the key mechanistic differences between electrochemical hydrogenation and hydrogenolysis of HMF. The results revealed that hydrogenation and hydrogenolysis of HMF involve the formation of different surface-adsorbed intermediates via different reduction mechanisms and that lowering the pH promoted the formation of the intermediates required for aldehyde and alcohol hydrogenolysis. This study for the first time explains the origins of the experimentally observed pH-dependent selectivities for hydrogenation and hydrogenolysis and offers a new mechanistic foundation upon which rational strategies to control electrochemical hydrogenation and hydrogenolysis can be developed.

Purpose: Measure the effect of inhaled pulmonary vasodilators on gas exchange in mechanically ventilated patients with COVID-19. Methods: A retrospective observational cohort study at three New York University Hospitals was performed including eighty-four mechanically ventilated SARS Cov-2 nasopharyngeal PCR positive patients, sixty nine treated with inhaled nitric oxide (iNO) and fifteen with inhaled epoprostenol (iEPO). The primary outcomes were change in PAO2:FIO2 ratio, oxygenation Index (OI), and ventilatory ratio (VR) after initiation of inhaled pulmonary vasodilators. Results: There was no significant change in PAO2:FIO2ratio after initiation of iNO (mean − 4.1, 95% CI -17.3-9.0, P = 0.54) or iEPO (mean − 3.4, 95% CI -19.7-12.9, P = 0.66), in OI after initiation of iNO (mean 2.1, 95% CI-0.04-4.2, P = 0.054) or iEPO (mean − 3.4, 95% CI -19.7-12.9, P = 0.75), or in VR after initiation of iNO (mean 0.17, 95% CI -0.03-0.36, P = 0.25) or iEPO (mean 0.33, 95% CI -0.0847-0.74, P = 0.11). PAO2:FIO2, OI and VR did not significantly change over a five day period starting the day prior to drug initiation in patients who received either iNO or iEPO assessed with a fixed effects model. Conclusion: Inhaled pulmonary vasodilators were not associated with significant improvement in gas exchange in mechanically ventilated patients with COVID-19.

A great deal of attention has been directed toward studying the electrochemical oxidation of 5-hydroxymethylfurfural (HMF), a molecule that can be obtained from biomass-derived cellulose and hemicellulose, to 2,5-furandicarboxylic acid (FDCA), a molecule that can replace the petroleum-derived terephthalic acid in the production of widely used polymers such as polyethylene terephthalate. NiOOH is one of the best and most well studied electrocatalysts for achieving this transformation; however, the mechanism by which it does so is still poorly understood. This study quantitatively examines how two different dehydrogenation mechanisms on NiOOH impact the oxidation of HMF and its oxidation intermediates on the way to FDCA. The first mechanism is a well-established indirect oxidation mechanism featuring chemical hydrogen atom transfer to Ni

Selective oxidation of alcohols to their corresponding aldehyde or carboxylic acid is one of the most important classes of organic synthesis reactions. In addition, electrochemical alcohol oxidation is considered a viable anode reaction that can be paired with H2 evolution or other reductive fuel production reactions in electrochemical and photoelectrochemical cells. NiOOH, a material that has been extensively studied as an oxygen evolution catalyst, is among the most promising electrocatalysts for selective alcohol oxidation. Electrochemical alcohol oxidation by NiOOH has been understood since the 1970s to proceed through a hydrogen atom transfer to NiOOH. In this study, we establish that there is a second, more dominant general alcohol oxidation pathway on NiOOH enabled at more positive potentials. Using a three-step electrochemical procedure we developed, we deconvoluted the currents corresponding to these two pathways for various alcohols and aldehydes. The results show that alcohols and aldehydes have a distinct difference in their respective preferences for the two oxidation pathways. Our three-step electrochemical procedure also allowed us to evaluate the Ni valence involved with the different oxidation pathways to elucidate their mechanistic differences. Using these experimental results coupled with a computational investigation, we propose that the new pathway entails hydride transfer from the substrate to Ni4+ sites in NiOOH. This study offers an essential foundation to understand various oxidative electrochemical dehydrogenation reactions on oxide and hydroxide-based catalytic electrodes.

Nitriles are highly important synthetic intermediates with applications in a wide variety of organic reactions including production of pharmaceuticals, fine chemicals, and agricultural chemicals. Thus, developing effective green routes to oxidize amines to nitriles is of great interest. One promising method to achieve the oxidation of primary amines to nitriles is through electrochemical oxidation on NiOOH electrodes. This reaction has long been thought to occur through an indirect mechanism consisting of a series of potential independent hydrogen atom transfer steps to catalytic Ni

Semiconducting single-walled carbon nanotubes (s-SWCNTs) are promising materials for solar energy conversion and photodetectors. Fullerenes and their derivatives, being widely employed as electron ...

Levels of anti-annexin A2 antibodies at admission strongly predicted mortality among hospitalised COVID-19 patients. Given its critical protective function in the lung, annexin A2 antagonism may play an important role in the pathophysiology of COVID-19.https://bit.ly/2UMPr9w

BackgroundAnnexin A2 is a phospholipid-binding protein involved in fibrinolysis, cell membrane stabilization and repair, and ensuring the integrity of the pulmonary microvasculature. Given the autoantibodies observed in COVID-19 and that Annexin A2 is a known target of antiphospholipid antibodies, we studied autoimmunity directed against Annexin A2 among hospitalized COVID-19 patients.MethodsWe used ELISA to identify the levels of IgG autoantibodies recognizing Annexin A2 and A5 among 86 hospitalized cases of COVID-19. Using logistic regression, we analyzed the association between anti-Annexin A2 and A5 antibody levels with mortality after adjusting for age, sex, race and key comorbidities.ResultsWe found higher average levels of anti-Annexin A2 antibodies among hospitalized COVID-19 patients that died when compared with non-critical hospitalized COVID-19 patients (p-value = 0.006) and critically ill COVID-19 patients (p-value = 0.04). No significant differences in anti-Annexin A5 antibody levels were identified. Regression analysis showed that anti-Annexin A2 antibody levels as measured in relative units strongly predicted mortality with an odds ratio of 9.3 (95% CI: 1.9 to 44.6, p=0.005). In contrast, anti-Annexin A5 antibody levels were not associated with higher mortality (95% CI: 0.5 to 15.2, p=0.22).ConclusionsWe determined that anti-Annexin A2 antibodies were elevated among hospitalized COVID-19 patients and these levels predicted mortality. It is known that inhibition of Annexin A2 induces systemic thrombosis, cell death, and non-cardiogenic pulmonary edema. Autoimmunity to Annexin A2 is a potential mechanism that may explain the key clinical findings of severe COVID-19.

The impact on the morphology nanoceramic materials generated from group 4 metal alkoxides ([M(OR)4]) and the same precursors modified by 6,6'-(((2-hydroxyethyl)azanediyl)bis(methylene))bis(2,4-di- tert-butylphenol) (referred to as H3-AM-DBP2 (1)) was explored. The products isolated from the 1:1 stoichiometric reaction of a series of [M(OR)4] where M = Ti, Zr, or Hf; OR = OCH(CH3)2(OPr i); OC(CH3)3(OBu t); OCH2C(CH3)3(ONep) with H3-AM-DBP2 proved, by single crystal X-ray diffraction, to be [(ONep)Ti( k4( O,O',O'',N)-AM-DBP2)] (2), [(OR)M(μ( O)- k3( O',O'',N)-AM-DBP2)]2 [M = Zr: OR = OPr i, 3·tol; OBu t, 4·tol; ONep, 5·tol; M = Hf: OR = OBu t, 6·tol; ONep, 7·tol]. The product from each system led to a tetradentate AM-DBP2 ligand and retention of a parent alkoxide ligand. For the monomeric Ti derivative (2), the metal was solved in a trigonal bipyramidal geometry, whereas for the Zr (3-5) and Hf (6, 7) derivatives a symmetric dinuclear complex was formed where the ethoxide moiety of the AM-DBP2 ligand bridges to the other metal center, generating an octahedral geometry. High quality density functional theory level gas-phase electronic structure calculations on compounds 2-7 using Gaussian 09 were used for meaningful time dependent density functional theory calculations in the interpretation of the UV-vis absorbance spectral data on 2-7. Nanoparticles generated from the solvothermal treatment of the ONep/AM-DBP2 modified compounds (2, 5, 7) in comparison to their parent [M(ONep)4] were larger and had improved regularity and dispersion of the final ceramic nanomaterials.

A 100% solid, curable liquid encapsulant for photovoltaic modules was developed using acrylic/urethane hybrid chemistry. These liquid acrylics are easily coated and cured with polyisocyanates to form rubbery solids with tunable cure time, excellent optical properties, and UV stability for over 5000 h of accelerated aging. Adhesion to a variety of substrates was good and remained high after aging as well. A variety of catalysts can be used for the curing reaction to tune pot life and cure time. The dielectric strength, surface resistivity, and volume resistivity are similar to commercial encapsulants, and the water vapor transmission rate is lower than EVA. The materials described herein are also useful as optically clear adhesives and potting agents.

Purpose of review Community-acquired pneumonia (CAP) is a pervasive disease that is encountered in outpatient and inpatient settings. CAP is the leading cause of death from an infectious disease and accounts for significant worldwide morbidity and mortality. This update reviews current advances that can be used to promote improved outcomes in CAP. Recent findings Early recognition of CAP and its severe presentations, with appropriate site of care decisions, leads to reduced patient mortality. In addition to traditional prognostic tools, certain serum biomarkers can assist in defining disease severity and guide treatment and management strategies. The use of macrolides as part of combination antibiotic therapy has shown beneficial mortality effects across the CAP disease spectrum, especially for those with severe illness. When treating community-associated, methicillin-resistant Staphylococcus aureus pneumonia, use of an antitoxin antibiotic is likely to be valuable. Adjunctive therapy with corticosteroids may prevent delayed clinical resolution in selected patients with severe CAP. Recent data expand on the interaction of CAP with comorbid disease, particularly cardiovascular disease, and its impact on mortality in CAP patients. Summary Improved diagnostic tools, optimized treatment regimens, and enhanced understanding of CAP-induced perturbations in comorbid disease states hold promise to improve patient outcomes.

Kawasaki disease is an acute, self-limited, febrile vasculitis typically seen in early childhood. Pulmonary involvement is uncommon and is not part of the conventional diagnostic criteria. We add to the literature a unique case of a 22year-old male with Kawasaki disease and pulmonary involvement. It illustrates the importance of recognizing unusual presentations of Kawasaki disease and highlights the possibility of pulmonary abnormalities on physical and imaging examination. Awareness of such presentations can help avoid delayed diagnosis, prevent the development of coronary aneurysms, and allow careful observation for imaging resolution.

Human immunodeficiency virus (HIV) infection is associated with an increased risk of venous thrombosis compared to that of the general population. In addition to traditional risk factors for venous thromboembolism (VTE) such as age, smoking and hospitalization, several of which are more prevalent in HIV-infected individuals, HIV-specific factors including the degree of immunosuppression, presence of opportunistic infections and malignancy, HIV-related coagulation abnormalities and medications used in the treatment of HIV, also contribute to this increased risk. The incidence of arterial thrombosis and cardiovascular disease is also increased in HIV infection, and VTE and arterial thrombosis share many risk factors. Importantly, increased chronic inflammation and immune activation persist in HIV infection even despite effective antiretroviral therapy and play an important role in these disease processes. Given the increased incidence of thrombosis in HIV, it is important that clinicians are alert to the condition in this population. Additionally, a diagnosis of HIV should be considered in individuals presenting with unexplained VTE.

More than a decade in the making, a new, legally binding treaty on mercury will be adopted by governments in the fall of 2013. The treaty's objective is to protect human health and the environment from anthropogenic mercury emissions through a range of provisions - including an article devoted to reducing exposure to mercury. Global emissions have increased since 2005, with the environmental health burden increasingly shifting to developing countries. Time is of the essence to reduce pollution because (i) exposure risk to mercury is much greater than previously thought and (ii) mercury already in the environment can be re-emitted via processes in the natural cycle, resulting in a longer lag time before pollution reduction can have a demonstrable effect on the food chain. Health professionals can assist in reducing exposure, choosing mercury-free products and urging governments to ratify the treaty as quickly as possible so that it can take effect.

Community-acquired pneumonia (CAP) encompasses a broad spectrum of disease severity and may require outpatient, inpatient, or intensive care management. Successful treatment hinges on expedient delivery of appropriate antibiotic therapy tailored to both the likely offending pathogens and the severity of disease. This review summarizes key principles in starting treatment and provides recommended empiric therapy regimens for each site of care. In addition, we discuss the antimicrobial and anti-inflammatory role macrolides play in CAP, as well as specific information for managing individual CAP pathogens such as community-acquired methicillin-resistant Staphylococcus aureus and drug-resistant Streptococcus pneumoniae. We also examine several novel antibiotics being developed for CAP and review the evidence guiding duration of therapy and current best practices for the transition of hospitalized patients from intravenous antibiotics to oral therapy.

Community-acquired pneumonia (CAP) is the leading cause of death from infectious disease in North America, accounting for over 60,000 deaths in the United States in 2005 (1). CAP encompasses a wide range of clinical presentations resulting in variable clinical outcomes. While mild forms lead to mortality in less than 5% and may be safely treated in outpatient settings, more severe forms necessitate intensive care unit (ICU) admission and are associated with mortality rates exceeding 30% (2).

Published guidelines for community-acquired pneumonia (CAP) have informed management and treatment recommendations for 25 years. Since inception, CAP guidelines have been developed for nearly every region of world, in part owing to improved mortality, clinical outcomes, and costs associated with implementation of guideline based care. This review highlights reasons why guidelines remain useful, overviews the similarities and differences among global CAP guidelines, and focuses on the treatment principles underpinning management recommendations, and addresses treatment issues that should be resolved in future CAP guidelines.

The steroid hormone ecdysone directs Drosophila metamorphosis via three heterodimeric receptors that differ according to which of three ecdysone receptor isoforms encoded by the EcR gene (EcR-A, EcR-B1, or EcR-B2) is activated by the orphan nuclear receptor USP. We have identified and molecularly mapped two classes of EcR mutations: those specific to EcR-B1 that uncouple metamorphosis, and embryonic-lethal mutations that map to common sequences encoding the DNA- and ligand-binding domains. In the larval salivary gland, loss of EcR-B1 results in loss of activation of ecdysone-induced genes. Comparable transgenic expression of EcR-B1, EcR-B2, and EcR-A in these mutant glands results, respectively, in full, partial, and no repair of that loss.

The steroid hormone ecdysone triggers coordinate changes in Drosophila tissue development that result in metamorphosis. To advance our understanding of the genetic regulatory hierarchies controlling this tissue response, we have isolated and characterized a gene, EcR, for a new steroid receptor homolog and have shown that it encodes an ecdysone receptor. First, EcR protein binds active ecdysteroids and is antigenically indistinguishable from the ecdysone-binding protein previously observed in extracts of Drosophila cell lines and tissues. Second, EcR protein binds DNA with high specificity at ecdysone response elements. Third, ecdysone-responsive cultured cells express EcR, whereas ecdysone-resistant cells derived from them are deficient in EcR. Expression of EcR in such resistant cells by transfection restores their ability to respond to the hormone. As expected, EcR is nuclear and found in all ecdysone target tissues examined. Furthermore, the EcR gene is expressed at each developmental stage marked by a pulse of ecdysone.