Highly Selective Production of C2+ Oxygenates from CO2 in Strongly Acidic Condition by Rough Ag-Cu Electrocatalyst.

The acidic electrocatalytic conversion of CO2 to multi-carbon (C2+) oxygenates is of great importance in view of enhancing carbon utilization efficiency and generating products with high energy densities, but suffering from low selectivity and activity. Herein, we synthesized Ag-Cu alloy catalyst with highly rough surface, by which the selectivity to C2+ oxygenates can be greatly improved. In a strongly acidic condition (pH=0.75), the maximum C2+ products Faradaic efficiency (FE) and C2+ oxygenates FE reach 80.4% and 56.5% at -1.9 V versus reversible hydrogen electrode, respectively, with a ratio of FEC2+ oxygenates to FEethylene up to 2.36. At this condition, the C2+ oxygenates partial current density is as high as 480 mA cm-2. The in situ Raman measurements and control experiments indicate that the high generation of C2+ oxygenates over the catalyst originates from its large surface roughness and Ag alloying.

Associations between PM2.5 Components and Mortality of Ischemic Stroke, Chronic Obstructive Pulmonary Disease and Diabetes in Beijing, China.

Ischemic stroke (IS), chronic obstructive pulmonary disease (COPD) and diabetes mellitus (DM) account for a large burden of premature deaths. However, few studies have investigated the associations between fine particular matter (PM2.5) components and mortality of IS, COPD and DM. We aimed to examine these associations in Beijing, China. Data on daily mortality, air pollutants and meteorological factors from 2008 to 2011 in Beijing were collected. Daily concentrations of five PM2.5 components, namely, sulfate ion (SO42-), ammonium ion (NH4+), nitrate ion (NO3-), organic matter (OM) and black carbon (BC), were obtained from the Tracking Air Pollution (TAP) database in China. The association between PM2.5 components and daily deaths was explored using a quasi-Poisson regression with the distributed lag nonlinear model (DLNM). The average daily concentrations of SO42-, NH4+, NO3-, OM and BC were 11.24, 8.37, 12.00, 17.34 and 3.32 µg/m3, respectively. After adjusting for temperature, relative humidity, pressure, particulate matter less than 10 µm in aerodynamic diameter (PM10), nitrogen dioxide (NO2) and sulfur dioxide (SO2), an IQR increase in OM at lag day 2 and lag day 6 was associated with an increased DM mortality risk (RR 1.038; 95% CI: 1.005-1.071) and COPD mortality risk (RR 1.013; 95% CI: 1.001-1.026). An IQR increase in BC at lag day 0 and lag day 6 was associated with increased COPD mortality risk (RR 1.228; 95% CI: 1.017-1.48, RR 1.059; 95% CI: 1.001-1.121). Cumulative exposure to SO42- and NH4+ was associated with an increased mortality risk for IS, with the highest effect found for lag of 0-7 days (RR 1.085; 95% CI: 1.010-1.167, RR 1.083; 95% CI: 1.003-1.169). These effects varied by sex and age group. This study demonstrated associations of short-term exposure to PM2.5 components with increased risk of IS, COPD and DM mortality in the general population. Our study also highlighted susceptible subgroups.

G protein subunit Gγ13-mediated signaling pathway is critical to the inflammation resolution and functional recovery of severely injured lungs.

Tuft cells are a group of rare epithelial cells that can detect pathogenic microbes and parasites. Many of these cells express signaling proteins initially found in taste buds. It is, however, not well understood how these taste signaling proteins contribute to the response to the invading pathogens or to the recovery of injured tissues. In this study, we conditionally nullified the signaling G protein subunit Gγ13 and found that the number of ectopic tuft cells in the injured lung was reduced following the infection of the influenza virus H1N1. Furthermore, the infected mutant mice exhibited significantly larger areas of lung injury, increased macrophage infiltration, severer pulmonary epithelial leakage, augmented pyroptosis and cell death, greater bodyweight loss, slower recovery, worsened fibrosis and increased fatality. Our data demonstrate that the Gγ13-mediated signal transduction pathway is critical to tuft cells-mediated inflammation resolution and functional repair of the damaged lungs.To our best knowledge, it is the first report indicating subtype-specific contributions of tuft cells to the resolution and recovery.

High-Efficiency Photocatalytic Oxidation of Benzyl Alcohol by NH2-UiO-66-(Indole-2,3-Dione)-Fe.

The photocatalytic oxidation of biomass-derived benzyl alcohol provides a promising way for the synthesis of benzoic acid, which is an important intermediate with wide applications. To improve the efficiency of photocatalytic benzyl alcohol oxidation to benzoic acid is of great interest. In this work, we propose the utilization of NH2-UiO-66-ID-Fe catalyst for photocatalytic oxidation of benzyl alcohol to benzoic acid, where NH2-UiO-66 is a typically used metal-organic framework, ID is indole-2,3-dione (ID) that has biocompatibility, light absorption property and can be covalently combined with amino-functionalized substances. The NH2-UiO-66-ID-Fe catalyst exhibits improved light absorption and photo-generated electron-hole separation ability compared with NH2-UiO-66. The photocatalytic performance of NH2-UiO-66-ID-Fe was examined for the oxidation of bio-based benzyl alcohol under mild conditions of air atmosphere, room temperature and no additive or additional oxidant involved. The results show that the conversion of benzyl alcohol and the selectivity to benzoic acid could both reach over 99 % in 6 h, and the generation rate of benzoic acid per gram of catalyst is 3.36 mmol g-1 h-1. The reaction mechanism was detected by radical trapping method and in situ electron paramagnetic resonance. This study presents an efficient and environmentally benign avenue for the synthesis of carboxylic acid compounds.

Synthesis of n-Propanol from CO2 Electroreduction on Bicontinuous Cu2O/Cu Nanodomains.

n-propanol is an important pharmaceutical and pesticide intermediate. To produce n-propanol by electrochemical reduction of CO2 is a promising way, but is largely restricted by the very low selectivity and activity. How to promote the coupling of *C1 and *C2 intermediates to form the *C3 intermediate for n-propanol formation is challenging. Here, we propose the construction of bicontinuous structure of Cu2O/Cu electrocatalyst, which consists of ultra-small Cu2O nanodomains, Cu nanodomains and large amounts of grain boundaries between Cu2O and Cu nanodomains. The n-propanol current density is as high as 101.6 mA cm-2 at the applied potential of -1.1 V vs. reversible hydrogen electrode in flow cell, with the Faradaic efficiency up to 12.1 %. Moreover, the catalyst keeps relatively stable during electrochemical CO2 reduction process. Experimental studies and theoretical calculations reveal that the bicontinuous structure of Cu2O/Cu can facilitate the *CO formation, *CO-*CO coupling and *CO-*OCCO coupling for the final generation of n-propanol.

Associations of metals and metal mixtures with glucose homeostasis: A combined bibliometric and epidemiological study.

This study employs a combination of bibliometric and epidemiological methodologies to investigate the relationship between metal exposure and glucose homeostasis. The bibliometric analysis quantitatively assessed this field, focusing on study design, predominant metals, analytical techniques, and citation trends. Furthermore, we analyzed cross-sectional data from Beijing, examining the associations between 14 blood metals and 6 glucose homeostasis markers using generalized linear models (GLM). Key metals were identified using LASSO-PIPs criteria, and Bayesian kernel machine regression (BKMR) was applied to assess metal mixtures, introducing an "Overall Positive/Negative Effect" concept for deeper analysis. Our findings reveal an increasing research interest, particularly in selenium, zinc, cadmium, lead, and manganese. Urine (27.6%), serum (19.0%), and whole blood (19.0%) were the primary sample types, with cross-sectional studies (49.5%) as the dominant design. Epidemiologically, significant associations were found between 9 metals-cobalt, copper, lithium, manganese, nickel, lead, selenium, vanadium, zinc-and glucose homeostasis. Notably, positive-metal mixtures exhibited a significant overall positive effect on insulin levels, and notable interactions involving nickel were identified. These finding not only map the knowledge landscape of research in this domain but also introduces a novel perspective on the analysis strategies for metal mixtures.

A Dataset on Population Activity Patterns in Typical Regions of North China.

This data article describes the "Typical Regional Activity Patterns" (TRAP) dataset, which is based on the Tackling Key Problems in Air Pollution Control Program. In order to explore the interaction between air pollution and physical activity, we collected activity patterns of 9,221 residents with different occupations and lifestyles for three consecutive days in typical regions (Jinan and Baoding) where air pollutant concentrations were higher than those in neighboring areas. The TRAP dataset consists of two aspects of information: demographic indicators (personal information, occupation, personal habits, and living situation) and physical activity pattern data (activity location and intensity); additionally, the exposure measures of physical activity patterns are included, which data users can match to various endpoints for their specific purpose. This dataset provides evidence for exploring the attributes of activity patterns of residents in northern China and for interdisciplinary researchers to develop strategies and measures for health education and health promotion.

Green solvent systems for material syntheses and chemical reactions.

It is of great significance to develop environmentally benign, non-volatile and recyclable green solvents for different applications. This feature article overviews the properties of green solvent systems (e.g., ionic liquids, supercritical carbon dioxide, deep eutectic solvents and mixed green solvent systems) and their applications in (1) framework material syntheses, including metal-organic frameworks, covalent organic frameworks and hydrogen-bonded organic frameworks, and (2) CO2 conversion reactions, including photocatalytic and electrocatalytic reduction reactions. Finally, the future perspective for research on green solvent systems is proposed from different aspects.

Tuft cells utilize taste signaling molecules to respond to the pathobiont microbe Ruminococcus gnavus in the proximal colon.

Tuft cells are a type of rare epithelial cells that have been recently found to utilize taste signal transduction pathways to detect and respond to various noxious stimuli and pathogens, including allergens, bacteria, protists and parasitic helminths. It is, however, not fully understood how many different types of pathogens they can sense or what exact molecular mechanisms they employ to initiate targeted responses. In this study, we found that an anaerobic pathobiont microbe, Ruminococcus gnavus (R. gnavus), can induce tuft cell proliferation in the proximal colon whereas the microbe's lysate can stimulate these proximal colonic tuft cells to release interleukin-25 (IL-25). Nullification of the Gng13 and Trpm5 genes that encode the G protein subunit Gγ13 and transient receptor potential ion channel Trpm5, respectively, or application of the Tas2r inhibitor allyl isothiocyanate (AITC), G protein Gßγ subunit inhibitor Gallein or the phospholipase Cß2 (PLCß2) inhibitor U73122 reduces R. gnavus-elicited tuft cell proliferation or IL-25 release or both. Furthermore, Gng13 conditional knockout or Trpm5 knockout diminishes the expression of gasdermins C2, C3 and C4, and concomitantly increases the activated forms of caspases 3, 8 and 9 as well as the number of TUNEL-positive apoptotic cells in the proximal colon. Together, our data suggest that taste signal transduction pathways are not only involved in the detection of R. gnavus infection, but also contribute to helping maintain gasdermin expression and prevent apoptotic cell death in the proximal colon, and these findings provide another strategy to combat R. gnavus infection and sheds light on new roles of taste signaling proteins along with gasdermins in protecting the integrity of the proximal colonic epithelium.

Alkaline Ionic Liquid Microphase Promotes Deep Reduction of CO2 on Copper.

Electrochemical reduction of CO2 to multicarbon (C2+) products using renewable energy sources is an important route to storing sustainable energy and achieving carbon neutrality. It remains a challenge to achieve high C2+ product faraday efficiency (FE) at ampere-level current densities. Herein, we propose the immobilization of an alkaline ionic liquid on copper for promoting the deep reduction of CO2. By this strategy, a C2+ FE of 81.4% can be achieved under a current density of 0.9 A·cm-2 with a half-cell energy conversion efficiency of 47.4% at -0.76 V vs reversible hydrogen electrode (RHE). Particularly, when the current density is as high as 1.8 A·cm-2, the C2+ FE reaches 71.6% at an applied potential of -1.31 V vs RHE. Mechanistic studies demonstrate that the alkaline ionic liquid plays multiple roles of improving the accumulation of CO2 molecules on the copper surface, promoting the activation of the adsorbed CO2, reducing the energy barrier of CO dimerization, stabilizing intermediates, and facilitating the C2+ product formation.

Cu/Cu2O nanocrystals for electrocatalytic carbon dioxide reduction to multi-carbon products.

We demonstrate the electrochemical conversion of carbon dioxide into multi-carbon products catalyzed by Cu/Cu2O nanocrystals, with a maximum C2+ faradaic efficiency of 75% in 0.10 M K2SO4 aqueous solution at -2.0 V versus Ag/AgCl and a partial current density of 34 mA cm-2.

AMF colonization affects allelopathic effects of Zea mays L. root exudates and community structure of rhizosphere bacteria.

Arbuscular mycorrhizal fungi (AMF) widely exist in the soil ecosystem. It has been confirmed that AMF can affect the root exudates of the host, but the chain reaction effect of changes in the root exudates has not been reported much. The change of soil microorganisms and soil enzyme vigor is a direct response to the change in the soil environment. Root exudates are an important carbon source for soil microorganisms. AMF colonization affects root exudates, which is bound to have a certain impact on soil microorganisms. This manuscript measured and analyzed the changes in root exudates and allelopathic effects of root exudates of maize after AMF colonization, as well as the enzymatic vigor and bacterial diversity of maize rhizosphere soil. The results showed that after AMF colonization, the contents of 35 compounds in maize root exudates were significantly different. The root exudates of maize can inhibit the seed germination and seedling growth of recipient plants, and AMF colonization can alleviate this situation. After AMF colonization, the comprehensive allelopathy indexes of maize root exudates on the growth of radish, cucumber, lettuce, pepper, and ryegrass seedlings decreased by 60.99%, 70.19%, 80.83%, 36.26% and 57.15% respectively. The root exudates of maize inhibited the growth of the mycelia of the pathogens of soil-borne diseases, and AMF colonization can strengthen this situation. After AMF colonization, the activities of dehydrogenase, sucrase, cellulase, polyphenol oxidase and neutral protein in maize rhizosphere soil increased significantly, while the bacterial diversity decreased but the bacterial abundance increased. This research can provide a theoretical basis for AMF to improve the stubble of maize and the intercropping mode between maize and other plants, and can also provide a reference for AMF to prevent soil-borne diseases in maize.

Electrocatalytic Carbon Dioxide Reduction to Ethylene over Copper-based Catalytic Systems.

The electrocatalytic carbon dioxide (CO2 ) conversion to ethylene (C2 H4 ) has attracted significant attention in recent years. Copper-based catalytic systems have been proven to be the most efficient for producing C2 H4 from electrocatalytic CO2 reduction reaction. In this review, we present the recent progress on the electrocatalytic CO2 reduction to C2 H4 over copper-based catalytic systems, mainly focusing on reaction mechanism, design of catalysts and influences of electrolyte, CO2 supplement and electrolyzer on activity, selectivity and stability.

Dual RNA and 16S ribosomal DNA sequencing reveal arbuscular mycorrhizal fungi-mediated mitigation of selenate stress in Zea mays L. and reshaping of soil microbiota.

Excessively high concentrations of selenium (Se) in soil are toxic to crop plants, and inoculation with arbuscular mycorrhizal fungi (AMF) can reverse Se stress in maize (Zea mays L.). To investigate the underlying mechanisms, maize seedlings were treated with sodium selenate (5 mg Se[VI] kg-1) and/or AMF (Funneliformis mosseae and Claroideoglomus etunicatum). Dual RNA sequencing in mycorrhiza and 16 S ribosomal DNA sequencing in soil were performed. The results showed that Se(VI) application alone decreased plant dry weight, but increased plant Se concentration, total Se content (mainly selenocysteine), and root superoxide content. Inoculation with either F. mosseae or C. etunicatum increased plant dry weight, decreased Se accumulation and selenocysteine proportion, enhanced root peroxidase activity, and alleviated oxidative stress in Se(VI)-treated plants. Inoculation also downregulated the expression of genes encoding Se transporters, assimilation enzymes, and cysteine-rich receptor-like kinases in Se(VI)-stressed plants, similar to plant-pathogen interaction and glutathione metabolism related genes. Conversely, genes encoding selenium-binding proteins and those related to phenylpropanoid biosynthesis were upregulated in inoculated plants under Se(VI) stress. Compared with Se(VI)-free plants, Se tolerance index, symbiotic feedback percentage on plant dry weight, and root colonization rate were all increased in inoculated plants under Se(VI) stress, corresponding to upregulated expression of 'key genes' in symbiosis. AMF inoculation increased bacterial diversity, decreased the relative abundances of selenobacteria related to plant Se absorption (e.g., Proteobacteria and Firmicutes), and improved bacterial network complexity in Se(VI)-stressed soils. We suggest that stress-mediated enhancement of mycorrhizal symbiosis contributed to plant Se(VI) tolerance, whereas AMF-mediated reshaping of soil bacterial community structure prevented excessive Se accumulation in maize.

Mycorrhizal symbiosis promotes the nutrient content accumulation and affects the root exudates in maize.

BACKGROUND: Arbuscular mycorrhizal fungi (AMF) are a group of important symbiotic microorganisms found in ecosystems. Maize is the second most produced food crop globally. To investigate the mechanisms by which mycorrhizal symbiosis improves maize yields, the effects of mycorrhizal symbiosis on root vigor, nutrient accumulation in various tissues, and root exudates were investigated. We propose the following hypothesis: The secretion of organic acids in root exudates has antagonistic or synergistic effects, which are related to the rhizosphere environment. AMF symbiosis will enhance this effect. RESULT: Rhizophagus aggreatus, Claroideoglomus etunicatum, and Funneliformis mosseae were used to inoculate maize plants separately; meanwhile, maize was inoculated with the above three fungi together for another processing. The plant tissues were sampled at five growth stages: V12 (twelve-leaf), VT (Tassel), R1 (Silking), R2 (Blister), and R4 (Dough stage). The root vigor, and nutrient content in different maize organs and organic acids in root exudates were determined in these stages. The results show that mycorrhizal symbiosis significantly improved the root vigor of maize, especially for plants inoculated with F. mosseae. AMF symbiosis significantly increased N, P, and K accumulation. Mixed inoculation with arbuscular mycorrhizal fungi significantly promoted the accumulation of N and K in maize. P accumulation was significantly promoted by C. etunicatum inoculation. Mycorrhizal symbiosis reduced the levels of protocatechuic, vanillic, citric, and ferulic acid in maize root exudates and increased the levels of p-hydroxybenzoic and caffeic acid. Except for syringic, chlorogenic and succinic acid, the levels of other organic acids in root exudates were higher in plants inoculated with F. mosseae than in other treatments. CONCLUSION: This study demonstrates that mycorrhizal symbiosis improves root vigor and promotes nutrient accumulation at various sites; in addition, mycorrhizal symbiosis affects the content of organic acids in root exudates.

Arbuscular mycorrhizal fungi reverse selenium stress in Zea mays seedlings by improving plant and soil characteristics.

Selenium (Se) is a beneficial trace element for certain animals including humans, while remaining controversial for plants. High Se concentration in soil is toxic to plants especially at seedling stage of the plants. Although, arbuscular mycorrhizal fungi (AMF) are important for plant stress resistance; but the mechanisms by which AMF alleviate Se stress in crop seedlings are unclear. Therefore, we investigated the potential strategies of AMF symbiosis to alleviate Se stress in maize (Zea mays) from plants and soil perspectives. Results showed that Se stress (Se application level > 5 mg kg-1) significantly inhibited leaf area, shoot dry weight, and root dry weight of maize (P < 0.05). In contrast, AM symbiosis significantly improved root morphology, increased nitrogen and phosphorus nutrition, promoted shoot growth, inhibited the transport of Se from soil/roots to shoots, and then diluted the concentration of Se in shoots (32.65-52.80%). In general, the response of maize growth to AMF was mainly observed in shoots rather than roots. In addition, AMF inoculation significantly increased the easily extractable glomalin-related soil protein and organic matter contents and decreased the availability of soil Se to the plant. Principal component analysis showed that AMF promoted growth and nutrition uptake of maize was the most dominant effect of Se stress alleviation, followed by the decrease of soil Se availability, limiting Se transport from soil/roots to shoots. Moreover, the expression of Se uptake-related ion transporter genes (ZmPht2, ZmNIP2;1, and ZmSultr1;3) in maize roots were down-regulated upon AM symbiosis which resultantly inhibited the uptake and transport of Se from soil to maize roots. Thus, AMF could impede Se stress in maize seedlings by improving plant and soil characteristics.

Insights into photoluminescence mechanisms of carbon dots: advances and perspectives.

Carbon dots (CDs) are potentially useful in many areas such as bioimaging, light-emitting diodes, and sensing because of their excellent optical properties, high biocompatibility, and low toxicity. Knowledge of their photoluminescence (PL) mechanisms, which have been widely studied, is of significance in guiding the synthesis and promoting applications of CDs with tunable PL emissions. However, the intrinsic mechanism of PL emission remains unclear, and a unified mechanism has not been found because of differences in particle structures. This review generalizes the categories of CDs, noting their structural diversity. Three types of PL mechanism pertaining to structural differences are outlined: internal factors dominated emission (including the conjugation effect, the surface state, and the synergistic effect), external factors dominated emission (including the molecular state and the environment effect), and crosslink-enhanced emission. Optical applications of CDs are also briefly mentioned. Finally, the prospects for research into PL mechanisms are discussed, noting the remaining challenges and directions for future work.

Photochromism of metal-organic frameworks based on carbazole-dicarboxylic acid and bipyridine: sensing adjustment by controlling strut-to-strut energy transfer.

In this paper, two energy-transfer photochromic metal-organic frameworks (MOFs) {[Zn(L)0.5(bpy)]·H2O·DMF}n (1) and {[Zn(L)0.5(bpe)]·2H2O·DMF}n (2) (H4L = 9,9'-(1,4-phenylenebis(methylene))bis(9H-carbazole-3,6-dicarboxylic acid), bpy = 4,4'-bipyridine, bpe = 4,4'-vinylenedipyridine) were designed and synthesized. Both 1 and 2 showed similar pillared-paddle wheel type frameworks with bpy and bpe as the chromophore, respectively, and L4- as the antenna-type light harvester, yielding strut-to-strut energy transfer (antenna behavior) within the well-ordered structures. Among them, 1 displayed excellent energy-transfer photochromic behavior under UV light accompanied by color transformation from colorless to purple. In addition, the photochromic behavior of 1 has obvious, fast, controllable and reversible characteristics. On the other hand, 2 showed a different energy-transfer photochromic behavior in the aspects of color changing, gamut, and sensitivity. The variation has been ascribed to the substitution of chromophore bpy in 1 with bpe in 2, which influences the efficiency of energy transfer within the MOFs. Therefore, with the structural diversity and tunability of MOFs, the sensitivity, color, and gamut of energy-transfer of the photochromic MOFs can be tuned by the appropriate choice of the constitutions of MOFs. This work will provide useful guidance for developing novel energy-transfer photochromic MOF materials.