Carbon dioxide electroreduction facilitates the sustainable synthesis of fuels and chemicals1. Although Cu enables CO2-to-multicarbon product (C2+) conversion, the nature of the active sites under ...operating conditions remains elusive2. Importantly, identifying active sites of high-performance Cu nanocatalysts necessitates nanoscale, time-resolved operando techniques3-5. Here, we present a comprehensive investigation ofthe structural dynamics during the life cycle of Cu nanocatalysts. A 7nm Cu nanoparticle ensemble evolves into metallic Cu nanograins during electrolysis before complete oxidation to single-crystal Cu2O nanocubes following post-electrolysis air exposure. Operando analytical and four-dimensional electrochemical liquid-cell scanning transmission electron microscopy shows the presence of metallic Cu nanograins under CO2 reduction conditions. Correlated high-energy-resolution time-resolved X-ray spectroscopy suggests that metallic Cu, rich in nanograin boundaries, supports undercoordinated active sites for C-C coupling. Quantitative structure-activity correlation shows that a higher fraction of metallic Cu nanograins leads to higher C2+ selectivity. A 7nm Cu nanoparticle ensemble, with a unity fraction of active Cu nanograins, exhibits sixfold higher C2+ selectivity than the 18 nm counterpart with one-third of active Cu nanograins. The correlation of multimodal operando techniques serves as a powerful platform to advance our fundamental understanding ofthe complex structural evolution of nanocatalysts under electrochemical conditions.
Naringenin (NGN) exhibits anti-inflammatory and antioxidant activities, but it remains undetermined its topical actions against ultraviolet B (UVB)-induced inflammation and oxidative stress in vivo. ...The purpose of this study was to evaluate the physicochemical and functional antioxidant stability of NGN containing formulations, and the effects of selected NGN containing formulation on UVB irradiation-induced skin inflammation and oxidative damage in hairless mice. NGN presented ferric reducing power, ability to scavenge 2,2'-azinobis (3-ethylbenzothiazoline- 6-sulfonic acid) (ABTS) and hydroxyl radical, and inhibited iron-independent and dependent lipid peroxidation. Among the three formulations containing NGN, only the F3 kept its physicochemical and functional stability over 180 days. Topical application of F3 in mice protected from UVB-induced skin damage by inhibiting edema and cytokine production (TNF-α, IL-1β, IL-6, and IL-10). Furthermore, F3 inhibited superoxide anion and lipid hydroperoxides production and maintained ferric reducing and ABTS scavenging abilities, catalase activity, and reduced glutathione levels. In addition, F3 maintained mRNA expression of cellular antioxidants glutathione peroxidase 1, glutathione reductase and transcription factor Nrf2 (nuclear factor erythroid 2-related factor 2), and induced mRNA expression of heme oxygenase-1. In conclusion, a formulation containing NGN may be a promising approach to protecting the skin from the deleterious effects of UVB irradiation.
Food production is challenged by changes in climate and land use and expanding human population growth. Proper pollination can increase the production and quality of fruit, nut, oil, and fiber ...crops.We reviewed crop dependence on pollinators and estimated the economic value of pollination per year for each crop in Brazil. We analyzed 141 crops and found that 85 depend on pollinators. Almost one-third of these crops have an essential or great dependence on pollinators. The economic contribution of pollinators totals ∼30% (∼US$12 billion) of the total annual agricultural income of the dependent crops (totalizing almost US$45 billion). However, half of these figures includes soybean crop (US$5.7 billion of pollinators' contribution and US$22 billion of annual income). Soybean was considered as having a modest dependence on pollinators, but this remains controversial because pollinator dependence might vary among different varieties cultivated in Brazil. Moreover, we have no information about pollinator dependence regarding some important crops, showing the urgent need for basic research into reproductive biology and pollination ecology.
Summary
The identification that T follicular helper (Tfh) cells is critical for the emergence of germinal centre responses prompted the study of CXCR5‐expressing CD4+ T cell subsets in autoimmunity. ...However, circulating CXCR5‐expressing T cells are heterogeneous by containing Forkhead box protein 3 (FoxP3)+ T follicular regulatory (Tfr) cells in addition to bona fide Tfh cells. Such heterogeneity may hamper the analysis of the contribution of specific follicular T cell subsets for autoimmune pathogenesis. Therefore, separate assessment of Tfh and Tfr populations offer greater opportunities for stratification of autoimmune patients, such as Sjögren’s syndrome patients.
Circulating CXCR5‐expressing follicular cells comprise Tfh and Tfr subsets.
We use classical electrodynamics calculations to investigate the plasmonic properties of the post-transition metals Al, Bi, Ga, In, and Sn, which are active in the ultraviolet, focusing in particular ...on the material- and resonance-dependent origins of plasmon broadening. Analytic Mie theory, the modified-long wavelength approximation, and the quasistatic dipole approximation together show that radiative processes dominate plasmon dephasing and damping in small (5–25 nm radius) Al, Bi, Ga, In, and Sn spheres. For Al, Ga, In, and Sn, the radiative contribution (∼0.5–2 eV) to the plasmon linewidth is more than 100-fold greater than the nonradiative contribution (0.001–0.02 eV) derived from the bulk dielectric function. This is significantly different than what is observed for Ag spheres, where nonradiative contributions (∼0.1 eV) are the primary source of broadening up to a radius of 25 nm. Overall, these data suggest that the plasmonic properties, dephasing, and lifetimes for Al, Ga, In, and Snand to a lesser extent Bispheres are qualitatively similar. To develop a more general understanding of the relationship between plasmon energy and linewidth, we use a model for ideal free-electron Drude metals. It is seen that the linewidth increases at higher energies even for lossless Drude metals, suggesting that the increased broadening observed in UV-active metals is a generalizable observation. These data have important implications for the use of these metals for ultraviolet plasmonics. The increased importance of radiative damping for post-transition metals could influence the ability to harvest photons, generate hot carriers, and enhance spectroscopy in the ultraviolet while providing new opportunities for manipulating high-energy photons.
The COVID-19 pandemic has added an enormous toll to the existing challenge of diabetes care world-wide. A large proportion of patients with COVID-19 requiring hospitalization and/or succumbing to the ...disease have had diabetes and other chronic conditions as underlying risk factors. In particular, individuals belonging to racial/ethnic minorities in the U.S. and other countries have been significantly and disproportionately impacted. Multiple and complex socioeconomic factors have long played a role in increasing the risk for diabetes and now for COVID-19.
Since the pandemic began, the global healthcare community has accumulated invaluable clinical experience on providing diabetes care in the setting of COVID-19. In addition, understanding of the pathophysiological mechanisms that link these two diseases is being developed.
The current clinical management of diabetes is a work in progress, requiring a shift in patient-provider interaction beyond the walls of clinics and hospitals: the use of tele-medicine when feasible, innovative patient education programs, strategies to ensure medication and glucose testing availability and affordability, as well as numerous ideas on how to improve meal plans and physical activity. Notably, this worldwide experience offers us the possibility to not only prepare better for future disasters but also transform diabetes care beyond the COVID-19 era.
•The COVID-19 pandemic has added an enormous toll to the existing challenge of diabetes care worldwide•Diabetes and other chronic conditions increase the risk of hospitalization and death from COVID-19•Comprehensive management of diabetes and common comorbidities is crucial to reducing morbidity and mortality rates•Individuals from racial or ethnic minorities have been disproportionately impacted by diabetes and COVID-19•Socioeconomic factors should be acknowledged and addressed at multiple levels to reduce diabetes & COVID-19 disease burdens•Lessons learned during this pandemic should influence the future of both disaster-based and routine diabetes care
Advances in electrocatalysis research rely heavily on building a thorough mechanistic understanding of catalyst active sites under realistic operating conditions. Only recently have techniques ...emerged that enable sensitive spectroscopic data collection to distinguish catalytically relevant surface sites from the underlying bulk material under applied potential in the presence of an electrolyte layer. Here, we demonstrate that operando high-energy-resolution fluorescence detected X-ray absorption spectroscopy (HERFD-XAS) is a powerful spectroscopic method which offers critical surface chemistry insights in CO2 electroreduction with sub-electronvolt energy resolution using hard X-rays. Combined with the high surface area-to-volume ratio of 5 nm copper nanoparticles, operando HERFD-XAS allows us to observe with clear evidence the breaking of chemical bonds between the ligands and the Cu surface as part of the ligand desorption process occurring under electrochemical potentials relevant for the CO2 reduction reaction (CO2RR). In addition, the dynamic evolution of oxidation state and coordination number throughout the operation of the nanocatalyst was continuously tracked. With these results in hand, undercoordinated metallic copper nanograins are proposed to be the real active sites in the CO2RR. This work emphasizes the importance of HERFD-XAS compared to routine XAS in catalyst characterization and mechanism exploration, especially in the complicated electrochemical CO2RR.
Aims
Ipragliflozin is a novel, selective inhibitor of sodium glucose co‐transporter 2 (SGLT2 inhibitor) in clinical development for type 2 diabetes mellitus (T2DM) treatment. This study assessed the ...efficacy and safety of different doses of ipragliflozin.
Methods
In a 12‐week, multicentre, double‐blind, randomized, placebo‐controlled, dose‐finding study patients with inadequate glycaemic control on metformin monotherapy (≥1500 mg/day) were randomized to one of four ipragliflozin treatment groups (12.5, 50, 150 or 300 mg once daily) or placebo. Primary efficacy outcome was mean change from baseline in haemoglobin A1c (HbA1c) compared to placebo at week 12. Adverse events (AEs), vital signs and laboratory safety measurements were assessed.
Results
Ipragliflozin dose dependently decreased HbA1c from baseline to week 12 compared to placebo (−0.22, −0.34, −0.40 and −0.48% for ipragliflozin 12.5, 50, 150 and 300 mg, respectively). Decreases in body weight and blood pressure were observed for all ipragliflozin groups. AEs occurred in 39.7–51.4% of the ipragliflozin groups and 39.4% of placebo patients. Urinary tract infections (1.4–6.9 vs. 6.1%), genital infections (0–4.3 vs. 1.5%) and hypoglycaemia (0–5.9 vs. 3.0%) were similar in the ipragliflozin and placebo groups, respectively, without dose dependency. There were no clinically relevant effects on other safety measurements.
Conclusions
Ipragliflozin treatment improved glycaemic control when added to metformin therapy and may be associated with weight loss and reductions in blood pressure compared to placebo. No safety or tolerability concerns were identified at any of the tested doses supporting the further development of ipragliflozin at ≥50 mg doses in T2DM patients.
Forest degradation in the Brazilian Amazon due to selective logging and forest fires may greatly increase the human footprint beyond outright deforestation. We demonstrate a method to quantify annual ...deforestation and degradation simultaneously across the entire region for the years 2000–2010 using high-resolution Landsat satellite imagery. Combining spectral mixture analysis, normalized difference fraction index, and knowledge-based decision tree classification, we mapped and assessed the accuracy to quantify forest (0.97), deforestation (0.85) and forest degradation (0.82) with an overall accuracy of 0.92. We show that 169,074 km2 of Amazonian forest was converted to human-dominated land uses, such as agriculture, from 2000 to 2010. In that same time frame, an additional 50,815 km2 of forest was directly altered by timber harvesting and/or fire, equivalent to 30% of the area converted by deforestation. While average annual outright deforestation declined by 46% between the first and second halves of the study period, annual forest degradation increased by 20%. Existing operational monitoring systems (PRODES: Monitoramento da Florestal Amazônica Brasileira por Satélite) report deforestation area to within 2% of our results, but do not account for the extensive forest degradation occurring throughout the region due to selective logging and forest fire. Annual monitoring of forest degradation across tropical forests is critical for developing land management policies as well as the monitoring of carbon stocks/emissions and protected areas.
In spite of the many studies examining alcohol consumption, recent reviews have indicated that binge drinking has not been extensively studied. Furthermore, it is becoming increasingly clear that ...sleep is associated with many physiological functions and to drug addictions. The present study aimed to evaluate the relationship between alcohol binge drinking and insomnia in college students of health sciences. All first-year health sciences students (n=286) were evaluated in a cross- sectional study. Envelopes containing the Insomnia Severity Index (ISI), the Alcohol, Smoking, and Substance Involvement Screening Test (ASSIST), and questions capturing sociodemographic data were distributed and collected in classes. It was found that most non-drinkers were female (70.6%), although there were no sex-related differences in the number of binge drinkers (more than 5 drinks on each occasion at least once a week), allowing statistical comparison. The Mann-Whitney U test indicated that the ISI scores were significantly greater in female than male binge drinkers (P=0.014). Moderate or severe insomnia was reported by 23% of the sample, with alcohol being the most frequently associated substance. A specialized intervention was suggested by ASSIST: brief for marijuana (19.2%) and tobacco (23.3%) use, and moderate (31.5%) or intensive (1.4%) for alcohol consumers. The data highlighted the need to pay attention to the habits of college students beyond obtaining scientific information. New data suggesting the influence of genetics on insomnia may be of importance when performing additional studies on the sex differences in alcohol binge drinking. Key words: Sleep; Alcohol; University; Insomnia; Binge drinking; Sex
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