Radical meta-C-H Halogenation of Azines via N-Benzyl Activation Strategy.

Regioselective halogenation of six-membered N-heteroarenes is crucial for precise functional derivatization. We present a meta-selective halogenation method for pyridines, quinolines, and isoquinolines via electrophilic halogen radical addition utilizing an N-benzyl activation strategy. This method achieves C3- and C5-dihalogenation in pyridines, C3- and C6-dihalogenation in quinolines, and C3-monohalogenation in isoquinolines. The feasibility and potential applications of this method were validated through scale-up reactions and the bromination of quinoline derivatives with biomolecular fragments.

Highly selective and additive-free Pd(OAc)2/CPP catalyzed hydroaminocarbonylation of alkynes.

Herein, the synthesis of branched α,ß-unsaturated amides by a hydroaminocarbonylation reaction of alkynes with various amine substrates such as aromatic amines, aliphatic amines, solid amine sources like NH4HCO3, and even strongly basic piperidines is reported, using a Pd(OAc)2/hybrid N-heterocyclic carbene-phosphine-phosphine (CPP) catalytic system. The reactions feature no additives, wide substrate scope, high selectivity (b/l > 99 : 1) and excellent yields. Mechanistic studies have disclosed that the reaction takes place via a palladium hydride pathway. CPP adopts a hybrid bidentate ligand conformation with a carbene-phosphine coordination mode, wherein one phosphorus atom remains externally accessible, potentially serving as a stabilizing auxiliary during catalytic cycles.

Efficient and selective external activator-free cobalt catalyst for hydroboration of terminal alkynes enabled by BiPyPhos.

Herein, a robust catalyst system, composed of a bipyridine-based diphosphine ligand (BiPyPhos) and a cobalt precursor Co(acac)2, is successfully developed and applied in the hydroboration of terminal alkynes, exclusively affording various versatile ß-E-vinylboronates in high yields at room temperature.

Organoboron-Promoted Electrochemical Chlorosulfonylation of Alkenes with Sulfonyl Chlorides.

Although extraordinary advances have been achieved by the transition-metal catalysis system, there is an urgent need to explore and develop alternative methodologies that are more environmentally friendly. Herein, we report an electrochemical chlorosulfonylation of alkenes using a wide range of sulfonyl chlorides with an inexpensive, degradable, and commercially available organoboron as a promoter. Furthermore, this protocol employs convergent paired electrolysis, reducing the need for sacrificial anodes and minimizing the extent of hydrogen evolution.

Unlocking iron metal as a cathode for sustainable Li-ion batteries by an anion solid solution.

Traditional cathode chemistry of Li-ion batteries relies on the transport of Li-ions within the solid structures, with the transition metal ions and anions acting as the static components. Here, we demonstrate that a solid solution of F- and PO43- facilitates the reversible conversion of a fine mixture of iron powder, LiF, and Li3PO4 into iron salts. Notably, in its fully lithiated state, we use commercial iron metal powder in this cathode, departing from electrodes that begin with iron salts, such as FeF3. Our results show that Fe-cations and anions of F- and PO43- act as charge carriers in addition to Li-ions during the conversion from iron metal to a solid solution of iron salts. This composite electrode delivers a reversible capacity of up to 368 mAh/g and a specific energy of 940 Wh/kg. Our study underscores the potential of amorphous composites comprising lithium salts as high-energy battery electrodes.

Lithiophilic Hydrogen-Substituted Graphdiyne Aerogels with Ionically Conductive Channels for High-Performance Lithium Metal Batteries.

Lithium (Li) metal stands as a promising anode in advancing high-energy-density batteries. However, intrinsic issues associated with metallic Li, especially the dendritic growth, have hindered its practical application. Herein, we focus on molecular combined structural design to develop dendrite-free anodes. Specifically, using hydrogen-substituted graphdiyne (HGDY) aerogel hosts, we successfully fabricated a promising Li composite anode (Li@HGDY). The HGDY aerogel's lithiophilic nature and hierarchical pores drive molten Li infusion and reduce local current density within the three-dimensional HGDY host. The unique molecular structure of HGDY provides favorable bulk pathways for lithium-ion transport. By simultaneous regulation of electron and ion transport within the HGDY host, uniform lithium stripping/platting is fulfilled. Li@HGDY symmetric cells exhibit a low overpotential and stable cycling. The Li@HGDY||lithium iron phosphate full cell retained 98.1% capacity after 170 cycles at 0.4 C. This study sheds new light on designing high-capacity and long-lasting lithium metal anodes.

Solvation-property relationship of lithium-sulphur battery electrolytes.

The Li-S battery is a promising next-generation battery chemistry that offers high energy density and low cost. The Li-S battery has a unique chemistry with intermediate sulphur species readily solvated in electrolytes, and understanding their implications is important from both practical and fundamental perspectives. In this study, we utilise the solvation free energy of electrolytes as a metric to formulate solvation-property relationships in various electrolytes and investigate their impact on the solvated lithium polysulphides. We find that solvation free energy influences Li-S battery voltage profile, lithium polysulphide solubility, Li-S battery cyclability and the Li metal anode; weaker solvation leads to lower 1st plateau voltage, higher 2nd plateau voltage, lower lithium polysulphide solubility, and superior cyclability of Li-S full cells and Li metal anodes. We believe that relationships delineated in this study can guide the design of high-performance electrolytes for Li-S batteries.

Wearable intelligent sweat platform for SERS-AI diagnosis of gout.

For the past few years, sweat analysis for health monitoring has attracted increasing attention benefiting from wearable technology. In related research, the sensitive detection of uric acid (UA) in sweat with complex composition based on surface-enhanced Raman spectroscopy (SERS) for the diagnosis of gout is still a significant challenge. Herein, we report a visualized and intelligent wearable sweat platform for SERS detection of UA in sweat. In this wearable platform, the spiral channel consisted of colorimetric paper with Ag nanowires (AgNWs) that could capture sweat for SERS measurement. With the help of photos from a smartphone, the pH value and volume of sweat could be quantified intelligently based on the image recognition technique. To diagnose gout, SERS spectra of human sweat with UA are collected in this wearable intelligent platform and analyzed by artificial intelligence (AI) algorithms. The results indicate that the artificial neural network (ANN) algorithm exhibits good identification of gout with high accuracy at 97%. Our work demonstrates that SERS-AI in a wearable intelligent sweat platform could be a feasible strategy for diagnosis of gout, which expands research on sweat analysis for comfortable and noninvasive health monitoring.

CO2 Enrichment Boosts Highly Selective Infrared-Light-Driven CO2 Conversion to CH4 by UiO-66/Co9S8 Photocatalyst.

Photocatalytic CO2 reduction to high-value chemicals is an attractive approach to mitigate climate change, but it remains a great challenge to produce a specific product selectively by IR light. Hence, UiO-66/Co9S8 composite is designed to couple the advantages of metallic photocatalysts and porous CO2 adsorbers for IR-light-driven CO2-to-CH4 conversion. The metallic nature of Co9S8 endows UiO-66/Co9S8 with exceptional IR light absorption, while UiO-66 dramatically enhances its local CO2 concentration, revealed by finite-element method simulations. As a result, Co9S8 or UiO-66 alone does not show observable IR-light photocatalytic activity, whereas UiO-66/Co9S8 exhibits exceptional activity. The CH4 evolution rate over UiO-66/Co9S8 reaches 25.7 µmol g-1 h-1 with ca.100% selectivity under IR light irradiation, outperforming most reported catalysts under similar reaction conditions. The X-ray absorption fine structure spectroscopy spectra verify the presence of two distinct Co sites and confirm the existence of metallic Co─Co bond in Co9S8. Energy diagrams analysis and transient absorption spectra manifest that CO2 reduction mainly occurs on Co9S8 for UiO-66/Co9S8, while density functional theory calculations demonstrate that high-electron-density Co1 sites are the key active sites, possessing lower energy barriers for further protonation of *CO, leading to the ultra-high selectivity toward CH4.

Correlating chemistry and mass transport in sustainable iron production.

Steelmaking contributes 8% to the total CO2 emissions globally, primarily due to coal-based iron ore reduction. Clean hydrogen-based ironmaking has variable performance because the dominant gas-solid reduction mechanism is set by the defects and pores inside the mm- to nm-sized oxide particles that change significantly as the reaction progresses. While these governing dynamics are essential to establish continuous flow of iron and its ores through reactors, the direct link between agglomeration and chemistry is still contested due to missing measurements. In this work, we directly measure the connection between chemistry and agglomeration in the smallest iron oxides relevant to magnetite ores. Using synthesized spherical 10-nm magnetite particles reacting in H2, we resolve the formation and consumption of wüstite (Fe1-xO)-the step most commonly attributed to whiskering. Using X-ray diffraction, we resolve crystallographic anisotropy in the rate of the initial reaction. Complementary imaging demonstrated how the particles self-assemble, subsequently react, and grow into elongated "whisker" structures. Our insights into how morphologically uniform iron oxide particles react and agglomerate in H2 reduction enable future size-dependent models to effectively describe the multiscale aspects of iron ore reduction.

Differential effects of parental and developmental temperatures on larval thermal adaptation in oviparous and viviparous model fish species.

Phenotypic plasticity has been identified as a major mechanism of response to changing temperatures. Parental effects are potentially important drivers of ecological and evolutionary dynamics, while developmental plasticity also plays a key role in generating phenotypic variation. However, little is known of the interaction between parental effects and developmental plasticity on the thermal phenotypes of fishes with different reproductive modes (i.e. oviparous vs. viviparous). To understand the contributions of inter- and intra-generational plasticity of thermal phenotypes (preferred temperature, avoidance temperatures, critical thermal thresholds) in fishes with different reproductive modes, we carried out a factorial experiment in which both breeding parents and offspring were exposed to lower (22 °C) or higher (28 °C) temperatures, using zebrafish (Danio rerio) and guppies (Poecilia reticulata) as representative oviparous and viviparous species. We found that offspring thermal preference and avoidance of both species were significantly influenced by parental effects and developmental plasticity, with higher thermal preference and avoidance consistent with higher background (parental) temperature treatments. However, parental effects were only found to impose significant effect on the thermal tolerances of guppies. The findings suggest that phenotypic plasticity, both within and across generations, may be an important mechanism to adapt to rapid climate changes, and that future temperature fluctuations may impose more profound effects on viviparous fish species in general.

Electrolytes with moderate lithium polysulfide solubility for high-performance long-calendar-life lithium-sulfur batteries.

Lithium-sulfur (Li-S) batteries with high energy density and low cost are promising for next-generation energy storage. However, their cycling stability is plagued by the high solubility of lithium polysulfide (LiPS) intermediates, causing fast capacity decay and severe self-discharge. Exploring electrolytes with low LiPS solubility has shown promising results toward addressing these challenges. However, here, we report that electrolytes with moderate LiPS solubility are more effective for simultaneously limiting the shuttling effect and achieving good Li-S reaction kinetics. We explored a range of solubility from 37 to 1,100 mM (based on S atom, [S]) and found that a moderate solubility from 50 to 200 mM [S] performed the best. Using a series of electrolyte solvents with various degrees of fluorination, we formulated the Single-Solvent, Single-Salt, Standard Salt concentration with Moderate LiPSs solubility Electrolytes (termed S6MILE) for Li-S batteries. Among the designed electrolytes, Li-S cells using fluorinated-1,2-diethoxyethane S6MILE (F4DEE-S6MILE) showed the highest capacity of 1,160 mAh g-1 at 0.05 C at room temperature. At 60 °C, fluorinated-1,4-dimethoxybutane S6MILE (F4DMB-S6MILE) gave the highest capacity of 1,526 mAh g-1 at 0.05 C and an average CE of 99.89% for 150 cycles at 0.2 C under lean electrolyte conditions. This is a fivefold increase in cycle life compared with other conventional ether-based electrolytes. Moreover, we observed a long calendar aging life, with a capacity increase/recovery of 4.3% after resting for 30 d using F4DMB-S6MILE. Furthermore, the correlation between LiPS solubility, degree of fluorination of the electrolyte solvent, and battery performance was systematically investigated.

Copper-Mediated and Palladium-Catalyzed Cross-Coupling of Indoles and N-Methylpyridinium Salts: A Practical Way to Prepare 3-(Pyridin-2-yl)indoles.

Herein, a Pd/Cu bimetallic-catalyzed direct C-H heteroarylation of pyridines via the traceless protecting group strategy is described. A series of N-methyl-activated pyridines and 1-methylindoles are coupled with high regioselectivity to produce the corresponding 3-(pyridin-2-yl)indoles in moderate to good yields, wherein related electron-rich heterocycles (e.g., indole, 1-methylpyrrole, benzofuran, benzo[b]thiophene) are also applicable. Streamlined operation, good functional group tolerance, and late-stage modifications make this twofold C-H activation protocol an attractive route for the synthesis of 3-(pyridin-2-yl)indole derivatives.

Ni Anchored to Hydrogen-Substituted Graphdiyne for Lithium Sulfide Cathodes in Lithium-Sulfur Batteries.

Lithium-sulfur (Li-S) batteries are promising candidates for next-generation energy storage systems due to their high theoretical energy density and the low cost of sulfur. However, slow conversion kinetics between the insulating S and lithium sulfide (Li2S) remains as a technical challenge. In this work, we report a catalyst featuring nickel (Ni) single atoms and clusters anchored to a porous hydrogen-substituted graphdiyne support (termed Ni@HGDY), which is incorporated in Li2S cathodes. The rapidly synthesized catalyst was found to enhance ionic and electronic conductivity, decrease the reaction overpotential, and promote more complete conversion between Li2S and sulfur. The addition of Ni@HGDY to commercial Li2S powder enabled a capacity of over 516 mAh gLi2S-1 at 1 C for over 125 cycles, whereas the control Li2S cathode managed to maintain just over 200 mAh gLi2S-1. These findings highlight the efficacy of Ni as a metal catalyst and demonstrate the promise of HGDY in energy storage devices.

An Evaluation of Fluorouracil plus Paclitaxel and Oxiliplatin as a First-Line Treatment for Advanced Gastric Squamous Cell Carcinoma.

Objective: To investigate the efficacy of fluorouracil (FU) combined with paclitaxel (PTX) and oxaliplatin (OXA) as the first-line treatment for advanced gastric signet ring cell carcinoma (SRCC) and its influence on human epidermal growth factor receptor 2 (HER-2) expression. Methods: We collected one hundred and sixty-eight patients with advanced gastric SRCC, including 87 patients treated with FU combined with PTX and OXA as the study group (SG) and 81 patients treated with FU combined with OXA as the control group (CG). We compared indicators such as efficacy and adverse reactions after treatment between the two groups and also detected serum HER-2 expression pre- and post-treatment. Results: The incidence of adverse reactions differed insignificantly between SG and CG (P > 0.05). SG presented a notably higher objective response rate (ORR) and disease control rate (DCR) than that of CG (P < 0.05). After treatment, the serum HER-2 expression level of patients in both groups decreased significantly (P < 0.05), and that in SG was significantly declined compared to CG (P < 0.05). HER-2 was negatively correlated with the efficacy of both SG and CG. The 1-year survival rate in SG (29.89%) was significantly higher than that in CG (16.05%) (P < 0.05). The median OS and PFS were higher in DG than that in CG (P < 0.05). Conclusion: FU combined with PTX and OXA can effectively improve the efficacy of first-line treatment for advanced gastric SRCC while reducing HER-2 expression, without increasing the adverse reaction rate. This treatment is worthy of clinical promotion.

Absorption, metabolism, and functions of hyaluronic acid and its therapeutic prospects in combination with microorganisms: A review.

Hyaluronic acid (HA) is key to the stability of the internal environment of tissues. HA content in tissues gradually decreases with age, causing age-related health problems. Exogenous HA supplements are used to prevent or treat these problems including skin dryness and wrinkles, intestinal imbalance, xerophthalmia, and arthritis after absorption. Moreover, some probiotics are able to promote endogenous HA synthesis and alleviate symptoms caused by HA loss, thus introducing potential preventative or therapeutic applications of HA and probiotics. Here, we review the oral absorption, metabolism, and biological function of HA as well as the potential role of probiotics and HA in increasing the efficacy of HA supplements.

Tandem Ring-Contraction/Regioselective C-H Iodination Reaction of Pyridinium Salts.

A facile route for direct access to the 4-iodopyrrole-2-carbaldehydes from pyridinium salts has been successfully developed, which undergoes cascade pyrrole-2-carbaldehydes construction/selective C4 position iodination process. Using Na2S2O8 as an oxidant and readily available sodium iodide as an iodine source, a variety of 4-iodopyrrole-2-carbaldehydes were obtained in good to excellent yields. Atom- and step-economy, good functional group tolerance, high regioselectivity, as well as mild conditions entail this transformation an alternative strategy for enriching pyrroles library.

Hydrogen-substituted graphdiyne-assisted ultrafast sparking synthesis of metastable nanomaterials.

Metastable nanomaterials, such as single-atom and high-entropy systems, with exciting physical and chemical properties are increasingly important for next-generation technologies. Here, we developed a hydrogen-substituted graphdiyne-assisted ultrafast sparking synthesis (GAUSS) platform for the preparation of metastable nanomaterials. The GAUSS platform can reach an ultra-high reaction temperature of 3,286 K within 8 ms, a rate exceeding 105 K s-1. Controlling the composition and chemistry of the hydrogen-substituted graphdiyne aerogel framework, the reaction temperature can be tuned from 1,640 K to 3,286 K. We demonstrate the versatility of the GAUSS platform with the successful synthesis of single atoms, high-entropy alloys and high-entropy oxides. Electrochemical measurements and density functional theory show that single atoms synthesized by GAUSS enhance the lithium-sulfur redox reaction kinetics in all-solid-state lithium-sulfur batteries. Our design of the GAUSS platform offers a powerful way to synthesize a variety of metastable nanomaterials.

Genome-wide SNPs reveal novel patterns of spatial genetic structure in Aedes albopictus (Diptera Culicidae) population in China.

Introduction: Since the second half of the 20th century, Aedes albopictus, a vector for more than 20 arboviruses, has spread worldwide. Aedes albopictus is the main vector of infectious diseases transmitted by Aedes mosquitoes in China, and it has caused concerns regarding public health. A comprehensive understanding of the spatial genetic structure of this vector species at a genomic level is essential for effective vector control and the prevention of vector-borne diseases. Methods: During 2016-2018, adult female Ae. albopictus mosquitoes were collected from eight different geographical locations across China. Restriction site-associated DNA sequencing (RAD-seq) was used for high-throughput identification of single nucleotide polymorphisms (SNPs) and genotyping of the Ae. albopictus population. The spatial genetic structure was analyzed and compared to those exhibited by mitochondrial cytochrome c oxidase subunit 1 (cox1) and microsatellites in the Ae. albopictus population. Results: A total of 9,103 genome-wide SNP loci in 101 specimens and 32 haplotypes of cox1 in 231 specimens were identified in the samples from eight locations in China. Principal component analysis revealed that samples from Lingshui and Zhanjiang were more genetically different than those from the other locations. The SNPs provided a better resolution and stronger signals for novel spatial population genetic structures than those from the cox1 data and a set of previously genotyped microsatellites. The fixation indexes from the SNP dataset showed shallow but significant genetic differentiation in the population. The Mantel test indicated a positive correlation between genetic distance and geographical distance. However, the asymmetric gene flow was detected among the populations, and it was higher from south to north and west to east than in the opposite directions. Conclusions: The genome-wide SNPs revealed seven gene pools and fine spatial genetic structure of the Ae. albopictus population in China. The RAD-seq approach has great potential to increase our understanding of the spatial dynamics of population spread and establishment, which will help us to design new strategies for controlling vectors and mosquito-borne diseases.

Isobaric tags for relative and absolute quantification-based proteomic analysis of host-pathogen protein interactions in the midgut of Aedes albopictus during dengue virus infection.

Aedes albopictus (Ae. albopictus), an important vector of dengue virus (DENV), is distributed worldwide. Identifying host proteins involved in flavivirus replication in Ae. albopictus and determining their natural antiviral mechanisms are critical to control virus transmission. Revealing the key proteins related to virus replication and exploring the host-pathogen interaction are of great significance in finding new pathways of the natural immune response in Ae. albopictus. Isobaric tags for relative and absolute quantification (iTRAQ) was used to perform a comparative proteomic analysis between the midgut of Ae. albopictus infected with DENV and the control. 3,419 proteins were detected, of which 162 were ≥ 1.2-fold differentially upregulated or ≤ 0.8-fold differentially downregulated (p < 0.05) during DENV infections. Differentially expressed proteins (DEPs) were mainly enriched in ubiquitin ligase complex, structural constituent of cuticle, carbohydrate metabolism, and lipid metabolism pathways. We found that one of the DEPs, a putative pupal cuticle (PC) protein could inhibit the replication of DENV and interact with the DENV-E protein. In addition, the result of immunofluorescence (IF) test showed that there was co-localization between ubiquitin carboxyl-terminal hydrolase (UCH) protein and the DENV-E protein, and virus infection reduced the level of this protein. iTRAQ-based proteomic analysis of the Ae. albopictus midgut identified dengue infection-induced upregulated and downregulated proteins. The interaction between the PC and UCH proteins in the midgut of Ae. albopictus might exert a natural antiviral mechanism in mosquito.