Water-Assisted Oxygen Activation During Selective Oxidation Reactions

The selective functionalization of hydrocarbons with oxygen to produce valuable commodity chemicals is inherently challenging, because of the thermodynamic stability of the complete combustion products. Emerging green synthesis routes and sustainable energy production also rely on the success of selective oxidation reactions. As one of the unselective by-products, water is always present under reaction conditions and numerous studies indicate that the catalytic activity and selectivity of selective oxidation reactions may be tuned by judiciously controlling the water content during the reaction. Some experimentally verified examples include the preferential oxidation of carbon monoxide, direct hydrogen peroxide synthesis, propene epoxidation and alcohol oxidation. Finally, it has been predicted that the direct conversion of methane to methanol can benefit from the right amount of water near the active site during oxygen activation

Finite Size Effects in Submonolayer Catalysts Investigated by CO Electrosorption on Pt_sML/Pd(100)

A combination of scanning tunneling microscopy, subtractively normalized interfacial Fourier transform infrared spectroscopy (SNIFTIRS), and density functional theory (DFT) is used to quantify the local strain in 2D Pt clusters on the 100 facet of Pd and its effect on CO chemisorption. Good agreement between SNIFTIRS experiments and DFT simulations provide strong evidence that, in the absence of coherent strain between Pt and Pd, finite size effects introduce local compressive strain, which alters the chemisorption properties of the surface. Though this effect has been widely neglected in prior studies, our results suggest that accurate control over cluster sizes in submonolayer catalyst systems can be an effective approach to fine-tune their catalytic properties

Active Learning Guided Computational Discovery of Plant-Based Redoxmers for Organic Nonaqueous Redox Flow Batteries

Organic nonaqueous redox flow batteries (O-NRFBs) are promising energy storage devices due to their scalability and reliance on sourceable materials. However, finding suitable redox-active organic molecules (redoxmers) for these batteries remains a challenge. Using plant-based compounds as precursors for these redoxmers can decrease their costs and environmental toxicity. In this computational study, flavonoid molecules have been examined as potential redoxmers for O-NRFBs. Flavone and isoflavone derivatives were selected as catholyte (positive charge carrier) and anolyte (negative charge carrier) molecules, respectively. To drive their redox potentials to the opposite extremes, in silico derivatization was performed using a novel algorithm to generate a library of > 40000 candidate molecules that penalizes overly complex structures. A multiobjective Bayesian optimization based active learning algorithm was then used to identify best redoxmer candidates in these search spaces. Our study provides methodologies for molecular design and optimization of natural scaffolds and highlights the need of incorporating expert chemistry awareness of the natural products and the basic rules of synthetic chemistry in machine learning

Physical activity and social support are associated with quality of life in middle-aged women

Purposes: This cross-sectional study assessed the quality of life and related factors of Vietnamese women during perimenopause in terms of vasomotor, psychosocial, physical, and sexual aspects. Materials and methods: A cross-sectional study on 400 middle-aged women was conducted in Hung Yen, a delta province in Vietnam. Data about socioeconomic characteristics, daily activity patterns, quality of life in terms of vasomotor, psychosocial, physical, and sexual aspects, and level of social support were collected. Tobit multivariate regression model was used to identify factors related to the quality of life among participants. Results: The symptoms of perimenopause appeared to worsen with the increase of age and the existence of such health issues as migraine and diabetes. Meanwhile, exercises, recreational activities, and social support appeared to alleviate the negative impact of perimenopausal symptoms on women. Conclusions: It is important to address the care needs of women during perimenopausal age, especially their sexual well-being, and development of specific healthcare services and programs focusing on sport, entertainment, and support for women in perimenopause should be facilitated

Effect of Corticosteroid-Sparing Treatment With Mycophenolate Mofetil vs Methotrexate on Inflammation in Patients With Uveitis: A Randomized Clinical Trial.

ImportanceMethotrexate and mycophenolate mofetil are commonly used immunomodulatory therapies for achieving corticosteroid-sparing control of noninfectious uveitis, but there is uncertainty about which drug is more effective.ObjectiveTo compare the effect of methotrexate and mycophenolate for achieving corticosteroid-sparing control of noninfectious intermediate uveitis, posterior uveitis, and panuveitis.Design, setting, and participantsThe First-line Antimetabolites as Steroid-sparing Treatment (FAST) uveitis trial screened 265 adults with noninfectious uveitis requiring corticosteroid-sparing immunosuppressive therapy from 9 referral eye centers in India, the United States, Australia, Saudi Arabia, and Mexico between August 22, 2013, and August 16, 2017. Follow-up ended on August 20, 2018.InterventionsPatients were randomized to receive oral methotrexate, 25 mg weekly (n = 107), or oral mycophenolate mofetil, 3 g daily (n = 109).Main outcomes and measuresThe primary outcome was treatment success at 6 months, which was defined as having control of inflammation in both eyes, no more than 7.5 mg prednisone daily and less than or equal to 2 drops of prednisolone acetate 1%, and no treatment failure due to safety or intolerability. Patients underwent follow-up to 12 months while receiving the same treatment or switched to the other antimetabolite, depending on their 6-month outcome.ResultsAmong 216 patients who were randomized (median age, 38 years; 135 (62.5%) women), 194 (89.8%) completed follow-up through 6 months. Treatment success occurred in 64 (66.7%) patients in the methotrexate group vs 56 (57.1%) in the mycophenolate group (difference, 9.5% [95% CI, -5.3% to 21.8%]; odds ratio [OR], 1.50 [95% CI, 0.81 to 2.81]; P = .20). Among patients with posterior uveitis or panuveitis, treatment success was achieved in 58 (74.4%) in the methotrexate group vs 42 (55.3%) in the mycophenolate group (difference, 19.1% [95% CI, 3.6% to 30.6%]; OR, 2.35 [95% CI, 1.16 to 4.90]; P = .02); whereas among patients with intermediate uveitis treatment success occurred in 6 (33.3%) in the methotrexate group vs 14 (63.6%) in the mycophenolate group (difference, -30.3% [95% CI, -51.6% to 1.1%]; OR, 0.29 [95% CI, 0.08 to 1.05]; P = .07; P for interaction = .004). Elevated liver enzymes were the most common nonserious laboratory adverse event, occurring in 14 patients (13.0%) in the methotrexate group and 8 patients (7.4%) in the mycophenolate group.Conclusions and relevanceAmong adults with noninfectious uveitis, the use of mycophenolate mofetil compared with methotrexate as first-line corticosteroid-sparing treatment did not result in superior control of inflammation. Further research is needed to determine if either drug is more effective based on the anatomical subtype of uveitis.Trial registrationClinicalTrials.gov Identifier: NCT01829295