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An efficient approach for the photosynthesis of various arylated 2-aryl-2H-indazoles (38 examples) in moderate to good yields (up to 87% yield) under mild conditions was developed by employing 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN) as an inexpensive photocatalyst. This protocol features wide substrate scope, good functional group tolerance, and operational simplicity. In addition, the strategy was successfully applied to the late-stage modification of drug molecules, and the meaningful introduction of complex drugs to the skeleton of 2H-Indazole was achieved for the first time.

Rapid detection of toxic and hazardous gases at trace concentrations plays a vital role in industrial, battlefield, and laboratory scenarios. Of interest are both sensitive as well as highly selective sensors. Whispering-gallery mode (WGM) microresonator-based biochemical sensors are among the most sensitive sensors in existence due to their long photon confinement times. One main concern with these devices, however, is their selectivity toward specific classes of target analytes. Here, we employ frequency locked WGM microtoroid optical resonators covalently modified with various polymer coatings to selectively detect the chemical warfare agent surrogate diisopropyl methylphosphonate (DIMP) as well as the toxic industrial chemicals formaldehyde and ammonia at parts-per-trillion concentrations (304, 434, and 117 ppt, respectively). This is 1-2 orders of magnitude better than previously reported, depending on the target, except for pristine graphene and pristine carbon nanotube sensors, which demonstrate similar detection levels but in vacuum and without selectivity. Selective polymer coatings include polyethylene glycol for DIMP sensing, accessed by the modification of commercially available materials, and 3-(triethoxysilyl) propyl-terminated polyvinyl acetate (PVAc) for ammonia sensing. Notably, we developed for the first time an efficient one-pot procedure to access 3-(triethoxysilyl) propyl-terminated PVAc that utilizes cobalt-mediated living radical polymerization and a nitroxyl polymer-terminating agent. Alkaline hydrolysis of PVAc coatings to form polyvinyl alcohol coatings directly bound to the microtoroid proved to be reliable and reproducible, leading to WGM sensors capable of the rapid and selective detection of formaldehyde vapors. The selectivity of these three polymer coatings as sensing media was predicted, in part, based on their functional group content and known reactivity patterns with the target analytes. Furthermore, we demonstrate that microtoroids coated with a mixture of polymers can serve as an all-in-one sensor that can detect multiple agents. We anticipate that our results will facilitate rapid early detection of chemical agents, as well as their surrogates and precursors.

The objective of this retrospective study was to establish the effect of the preoperative body mass index (BMI) on early outcomes of recipients after a kidney transplant, including liver and kidney function and fasting blood glucose recovery.Our analytical cohort were patients who had undergone a kidney transplant at The First Affiliated Hospital of USTC [2016-2019]. The BMI classifications were underweight (18.5 kg/mWe enrolled 831 recipients in the study. The percentage of patients with normal serum creatinine and normal urea nitrogen in the BMI ≥24 group was lower at different periods after surgery (P0.05). The percentage of patients with normal uric acid in the normal weight group was higher on day 1 and the first week after surgery (P0.001). In the first and second weeks postsurgery, the percentage of patients with aspartate transaminase/alanine aminotransaminase in the BMI ≥24 group was lower (P.005). In the first week postsurgery, the percentage of patients with normal albumin/globulin in the normal weight group was higher (P.05). No statistically significant difference among the 3 groups was found in the incidence of hyperglycemia (P.05).The patients who were overweight or obese preoperatively had poorer renal and liver functions postoperatively. Targeted interventions to control or mitigate rates of overweight or obesity preoperatively should be identified.

Superhydrophobic surfaces have gained sustained attention because of their extensive applications in the fields of self-cleaning, anti-icing, and drag reduction systems. Water droplets must have large apparent contact angle (CA) (150°) and small CA hysteresis (10°) on these surfaces. However, previous research usually involves complex fabrication strategies to modify the surface wettability. It is also challenging to maintain the temporal and mechanical stability of the delicate surface textures. Here, we develop a one-step solvent-free sand-in method to fabricate robust superhydrophobic surfaces directly atop various substrates with an apparent CA up to ∼163.8° and hysteresis less than 5°. The water repellency can withstand 100 Scotch tape peeling tests and remain stable after being stored under ambient humid conditions in Houston, Texas, for 18 months or being heated at 130 °C in air for 24 h. The superhydrophobic surfaces have excellent anti-icing ability, including a ∼2.6× longer water freezing time and ∼40% smaller ice adhesion strength with the temperature as low as -35 °C. Since the surface layers are fabricated by sanding the substrates with the powder additives, the surface damage can be repaired by a direct re-sanding treatment with the same powder additives. Further sand-in condition screenings broaden surface wettability from hydrophilic to superhydrophobic. The sand-in method induces the surface modification and the formation of the tribofilm. Surface and materials characterizations reveal that both microstructures and nanoscale asperities of the tribofilms contribute to the robust superhydrophobic features of sanded surfaces.

Under the background of rural revitalization, the important goal is to help the sustainable development of villages and towns. While implementing the concept of green development, development needs to promote the inheritance and continuous activation of rural culture. In this paper, the ancient architectural wisdom and green design concept contained in the traditional houses in the south of the Yangtze River were studied, and how to extract the low-carbon ideas and combine them with modern green technology to achieve the parallel development of villages and towns and the preservation and promotion of traditional culture was explored. The research results also provide new ideas for village development and cultural heritage in a carbon-neutral context.

Endowing strain sensors with superhydrophobicity is of great importance to guarantee their long-term service under harsh environments (such as wet, acid, alkali and salt atmospheres), whereas, the development of superhydrophobic strain sensors remains a great challenge. Herein, we realized a superhydrophobic and highly sensitive sensor for subtle human motion detection by designing a superhydrophobic and electrically conductive coating on cotton textile, via a facile drop-coating method. The resultant strain sensor showed a large water contact angle of 161.3 ° and a low sliding angle of 3.8 ° The superhydrophobic characteristics can keep almost unchanged even after undergoing 1000 peeling cycles, 1000 stretching-release cycles, and 1000 bending-releasing cycles, revealing its excellent mechanical robustness. High sensitivity with the maximum gage factor of 169 was achieved for the strain sensor under a small strain of 0–10%, and the sensing performance also showed well durability. Moreover, our sensor can effectively detect various subtle human physiological signals and body motions even under harsh conditions. These admirable features make the sensor promising applications in wearable electronics, personalized health monitoring, sound recognition, and so on.

Background Conventional dissolving microneedles (DMNs) face significant challenges in anti-melanoma therapy due to the lack of active thrust to achieve efficient transdermal drug delivery and intra-tumoral penetration. Methods In this study, the effervescent cannabidiol solid dispersion-doped dissolving microneedles (Ef/CBD-SD@DMNs) composed of the combined effervescent components (CaCO3 & NaHCO3) and CBD-based solid dispersion (CBD-SD) were facilely fabricated by the “one-step micro-molding” method for boosted transdermal and tumoral delivery of cannabidiol (CBD). Results Upon pressing into the skin, Ef/CBD-SD@DMNs rapidly produce CO2 bubbles through proton elimination, significantly enhancing the skin permeation and tumoral penetration of CBD. Once reaching the tumors, Ef/CBD-SD@DMNs can activate transient receptor potential vanilloid 1 (TRPV1) to increase Ca2+ influx and inhibit the downstream NFATc1-ATF3 signal to induce cell apoptosis. Additionally, Ef/CBD-SD@DMNs raise intra-tumoral pH environment to trigger the engineering of the tumor microenvironment (TME), including the M1 polarization of tumor-associated macrophages (TAMs) and increase of T cells infiltration. The introduction of Ca2+ can not only amplify the effervescent effect but also provide sufficient Ca2+ with CBD to potentiate the anti-melanoma efficacy. Such a “one stone, two birds” strategy combines the advantages of effervescent effects on transdermal delivery and TME regulation, creating favorable therapeutic conditions for CBD to obtain stronger inhibition of melanoma growth in vitro and in vivo. Conclusions This study holds promising potential in the transdermal delivery of CBD for melanoma therapy and offers a facile tool for transdermal therapies of skin tumors.

The prediction of tribological characteristics of the piston ring-cylinder liner friction (PRCL) assembly near the top dead center has been a difficult area of research. This study explores the micro-friction behavior of PRCL assemblies near the top dead center in engines using the molecular dynamics approach. The tribological characteristics of the PRCL were analyzed under various operating conditions such as ring sliding speed, ring back load, operating temperature, and lubricant supply amount. The liner surface morphology, liner wear, and lubricant film distribution were used to evaluate the tribological characteristics. It was determined that the lubricant supply amount has the most significant impact on the micro-friction behavior of the PRCL assembly.

Sustained retina drug delivery and rational drug combination are considered essential for enhancing the efficacy of therapy for wet age-related macular degeneration (wAMD) due to the conservative structure of the posterior ocular segment and the multi-factorial pathological mechanism. Designing a drug co-delivery system that can simultaneously achieve deep penetration and long-lasting retention in the vitreous is highly desired, yet remains a huge challenge. In this study, we fabricated Bor/RB-M@TRG as an intravitreal-injectable hydrogel depot for deep penetration into the posterior ocular segment and long-lasting distribution in the retinal pigment epithelium (RPE) layer. The Bor/RB-M@TRG consisted of borneol-decorated rhein and baicalein-coloaded microemulsions (Bor/RB-M, the therapy entity) and a temperature-responsive hydrogel matrix (the intravitreal depot). Bor/RB-M exhibited the strongest in vitro anti-angiogenic effects among all the groups studied, which is potentially associated with improved cellular uptake, as well as the synergism of rhein and baicalein, acting via anti-angiogenic and anti-oxidative stress pathways, respectively. Importantly, a single intravitreal (IVT) injection with Bor/RB-M@TRG displayed significant inhibition against the CNV of wAMD model mice, compared to all other groups. Particularly, coumarin-6-labeled Bor/RB-M@TRG (Bor/C6-M@TRG) could not only deeply penetrate into the retina but also stably accumulate in the RPE layer for at least 14 days. Our design integrates the advantages of borneol-decorated microemulsions and hydrogel depots, offering a promising new approach for clinically-translatable retinal drug delivery and synergistic anti-wAMD treatment.

Cyanosporus is a genus widely distributed in Asia, Europe, North America, South America and Oceania. It grows on different angiosperm and gymnosperm trees and can cause brown rot of wood. Blue-tinted basidiomata of Cyanosporus makes it easy to distinguish from other genera, but the similar morphological characters make it difficult to identify species within the genus. Phylogeny and taxonomy of Cyanosporus were carried out based on worldwide samples with an emphasis on Chinese collections, and the species diversity of the genus is updated. Four new species, C. flavus, C. rigidus, C. subungulatus and C. tenuicontextus, are described based on the evidence of morphological characters, distribution areas, host trees and molecular phylogenetic analyses inferred from the internal transcribed spacer (ITS) regions, the large subunit of nuclear ribosomal RNA gene (nLSU), the small subunit of nuclear ribosomal RNA gene (nSSU), the small subunit of mitochondrial rRNA gene (mtSSU), the largest subunit of RNA polymerase II (RPB1), the second largest subunit of RNA polymerase II (RPB2), and the translation elongation factor 1-α gene (TEF). Our study expanded the number of Cyanosporus species to 35 around the world including 23 species from China. Detailed descriptions of the four new species and the geographical locations of the Cyanosporus species in China are provided.

Carbon nanohoops with donor-acceptor (D-A) structures are attractive electronic materials and biological fluorophores, but their synthesis is usually challenging. Moreover, the preparation of D-A nanohoop fluorophores exhibiting high fluorescence quantum yields beyond 500 nm remains a key challenge. This study presents a modular synthetic approach based on an efficient metal-free cyclocondensation reaction that readily produced nine congeners with D-A or donor-acceptor-donor' (D-A-D') structures, one of which is water-soluble. The tailored molecular design of nanohoops enabled a systematic and detailed study of their host-guest complexation with fullerene, optical properties, and charge transfer (CT) dynamics using X-ray crystallography, fluorescence titration, steady and ultrafast transient absorption spectroscopy, and theoretical calculations. The findings revealed intriguing physical properties associated with D-A motifs, such as tight binding with fullerene, moderate fluorescence quantum yields (37-67%) beyond 540 nm, and unique solvation-controlled CT relaxation of D-A-D' nanohoops, where two CT states (D-A and A-D') can be effectively tuned by solvation, resulting in dramatically changed relaxation pathways in different solvents.

Leptoporus is a rare and remarkable genus, mainly occurring in coniferous forests in the Northern Hemisphere. Recent phylogenetic studies showed that Leptoporus belongs to Irpicaceae in the phlebioid clade. It is worth noting that most species in the phlebioid clade can cause white-rot decay, except for the Leptoporus species, which can cause a brown-rot decay. In this study, we performed phylogenetic and taxonomic studies of Leptoporus and related genera. Molecular phylogenetic analyses were conducted based on sequences from multiple loci including the internal transcribed spacer (ITS) regions, the large subunit of nuclear ribosomal RNA gene (nLSU), the largest subunit of RNA polymerase II gene (RPB1), the second largest subunit of RNA polymerase II gene (RPB2), and the translation elongation factor 1-α gene (TEF1). Combined with morphological characteristics, a new species, Leptoporus submollis sp. nov., is discovered and illustrated from Southwest China.

The genus Hydnellum is a kind of ectomycorrhizal fungi that can play a role in the material cycle by connecting the plant roots to the soil, and some species of Hydnellum are medicinal fungi with vital research value. The species diversity of Hydnellum is unclear in China. In this study, five new species of Hydnellum are described from China based on morphological characters and phylogenetic analyses inferred from two datasets of ITS + LSU and ITS + LSU + SSU + RPB2 sequences. H. chocolatum is characterized by its chocolate basidiomata with the fibrillose, spongy to tomentose pileal surface, and subglobose to globose basidiospores measuring (4.5–)5–6 × 4–5(–5.8) μm. H. concentricum is characterized by its zonate pileal surface, thin context, short stipe, presence of both simple septa and clamp connections in generative hyphae of spines, and subglobose to ellipsoidal basidiospores measuring (3.5–)4–5(–5.2) × (3.2–)3.5–5 μm. H. crassipileatum is characterized by its thick pileus with the reddish brown to grayish brown pileal surface, and subglobose to ellipsoidal basidiospores measuring 4–6(–6.5) × 4–5.5 μm. H. melanocarpum is characterized by its vinaceous brown to black pileus with spongy pileal surface, presence of both simple septa and clamp connections in generative hyphae of spines, and subglobose basidiospores measuring 4.5–5.5(–6) × (3.5–)3.8–5.1 μm. H. radiatum is characterized by its radially aligned stripes on pileal surface, grayish brown context, short stipe, and subglobose to ellipsoidal basidiospores measuring (3.5–)4–5 × 3–4.5(–5) μm. Full descriptions, illustrations, and phylogenetic trees to show the placement of the new species are provided.

The genus

Organizations are increasingly relying on data to support decisions. When data contains private and sensitive information, the data owner often desires to publish a synthetic database instance that is similarly useful as the true data, while ensuring the privacy of individual data records. Existing differentially private data synthesis methods aim to generate useful data based on applications, but they fail in keeping one of the most fundamental data properties of the structured data -- the underlying correlations and dependencies among tuples and attributes (i.e., the structure of the data). This structure is often expressed as integrity and schema constraints, or with a probabilistic generative process. As a result, the synthesized data is not useful for any downstream tasks that require this structure to be preserved. This work presents Kamino, a data synthesis system to ensure differential privacy and to preserve the structure and correlations present in the original dataset. Kamino takes as input of a database instance, along with its schema (including integrity constraints), and produces a synthetic database instance with differential privacy and structure preservation guarantees. We empirically show that while preserving the structure of the data, Kamino achieves comparable and even better usefulness in applications of training classification models and answering marginal queries than the state-of-the-art methods of differentially private data synthesis., Update based on reviewers' comments

Insufficient infiltration of T cells severely compromises the antitumor efficacy of adoptive cell therapy (ACT) against solid tumors. Here, we present a facile immune cell surface engineering strategy aiming to substantially enhance the anti-tumor efficacy of Th9-mediated ACT by rapidly identifying tumor-specific binding ligands and improving the infiltration of infused cells into solid tumors. Non-genetic decoration of Th9 cells with tumor-targeting peptide screened from phage display not only allowed precise targeted ACT against highly heterogeneous solid tumors but also substantially enhanced infiltration of CD8

The present study was aimed to identify hub genes associated with recurrent spontaneous abortion (RSA) via both bioinformatics analysis and clinical verification, also to evaluate the related pathways and immune infiltration situation of RSA, for exploring its underlying mechanism.We screened candidate hub genes associated with RSA via bioinformatic analysis in the microarray datasets GSE22490 downloaded from the Gene Expression Omnibus (GEO) database. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and Western blotting were used to validate these hub genes. Several kinds of enrichment analysis were carried out to find out the pathways related to RSA. Additionally, CIBERSORT was used for evaluation of local immune Infiltration status of RSA.There were 536 differentially expressed genes (DEGs) including 301 upregulated and 235 downregulated genes in RSA group compared with healthy control group. Four hub genes (STAT3, TLR2, TLR4 and CD86) were finally screened out according to the protein-protein interaction (PPI) network analysis, RT-qPCR and Western blotting. Enrichment analysis showed that Toll-like receptor signaling pathway, neutrophil chemotaxis, chemokine signaling pathway and Fc gamma receptor-mediated phagocytosis were strongly associated with RSA. And in immune infiltration analysis, RSA tissue was found containing a higher proportion of monocytes and eosinophils.This study screened out four hub genes and several important pathways changed in the trophoblastic tissue of RSA patients. We also found that monocytes and eosinophils may be involved in RSA. These findings provide theoretical basis for further studies on the mechanisms of RSA.

Turbostratic layers in 2D materials have an interlayer misalignment. The lack of alignment expands the intrinsic interlayer distances and weakens the optical and electronic interactions between adjacent layers. This introduces properties distinct from those structures with well-aligned lattices and strong coupling interactions. However, direct and rapid synthesis of turbostratic materials remains a challenge owing to their thermodynamically metastable properties. Here, a flash Joule heating (FJH) method to achieve bulk synthesis of boron-carbon-nitrogen ternary compounds with turbostratic structures by a kinetically controlled ultrafast cooling process that takes place within milliseconds (10

Small nucleolar RNA (snoRNA) plays important role in various histogenesis. Whether snoRNA plays a role in adipogenesis is unknown. SNORD126 is a C/D box snoRNA. We previously demonstrated that SNORD126 promoted hepatocellular carcinoma cell growth by activating the phosphoinositide 3-kinase-protein kinase B (Akt) pathway through upregulating fibroblast growth factor receptor 2 expression. In the present study, we found that the expression of SNORD126 was downregulated in the obesity-related tissues in high-fat diet-fed rats. Overexpression of SNORD126 in 3T3-L1 cells promoted adipocytes differentiation. SNORD126 significantly increased the expression of CCAAT/enhancer-binding protein α, fatty acid-binding protein 4, peroxisome proliferative-activated receptor-γ, and the phosphorylation of Akt and p70S6K. Overexpression of SNORD126 in human adipose-derived stem cells stimulated adipogenesis and increased phosphorylation of Akt. Meanwhile, SNORD126 increased the messenger RNA and protein levels of cyclin D1 and cyclin-dependent kinase 2, which promoted mitotic clonal expansion progression during the early stage of 3T3-L1 cell differentiation. We further found that SNORD126 accelerated the growth of the groin fat pad and increased phosphorylation of Akt and p70S6K in rats. Overall, our results suggested that SNORD126 promoted adipocyte differentiation through increasing phosphorylation of Akt and p70S6K both in vitro and in vivo.

The present study investigated the effects of dietary astaxanthin on the growth, blood biochemical, antioxidant, immune and inflammatory response in lipopolysaccharide‐challenged Channa argus. A total of 0, 50, 100 and 200 mg/kg of astaxanthin were added to the basal die for 56 days. After the feeding experiment, each group was subjected to a lipopolysaccharide challenge (except for the Control group). The results showed that adding astaxanthin to the diet can significantly increase the weight gain and specific growth rate and decrease the feed conversion ratio of C. argus; the highest weight gain, specific growth rate and minimum feed conversion ratio occurred in the 100 mg/kg group. Furthermore, dietary astaxanthin supplementation can alleviate the negative effects of lipopolysaccharides by increasing the levels of alkaline phosphatase, lysozyme, complement 3, complement 4, total serum protein, albumin, globulin, superoxide dismutase, catalase and glutathione peroxidase and decrease the serum cortisol, aspartate aminotransferase, alanine aminotransferase, glutathione peroxidase, and malondialdehyde. Dietary astaxanthin supplementation also can decrease the relative expression of inflammatory genes (nuclear factor κB, interleukin‐1, interleukin‐8 and tumour necrosis factor‐α) in the liver, spleen, kidney and intestine. To summarise, dietary astaxanthin addition can improve the growth performance and attenuate the negative effects of lipopolysaccharide challenge in C. argus. The optimal amount of astaxanthin is 100 mg/kg.

Quorum sensing (QS) is a ubiquitous cell–cell communication mechanism that can be employed to autonomously and dynamically control metabolic fluxes. However, since the functions of genetic components in the circuits are not fully understood, the developed QS circuits are still less sophisticated for regulating multiple sets of genes or operons in metabolic engineering applications. Here, we discover the regulatory roles of a CRP-binding site and the lux box to −10 region within luxR-luxI intergenic sequence in controlling the lux-type QS promoters. By varying the numbers of the CRP-binding site and redesigning the lux box to −10 site sequence, we create a library of QS variants that possess both high dynamic ranges and low leakiness. These circuits are successfully applied to achieve diverse metabolic control in salicylic acid and 4-hydroxycoumarin biosynthetic pathways in Escherichia coli. This work expands the toolbox for dynamic control of multiple metabolic fluxes under complex metabolic background and presents paradigms to engineer metabolic pathways for high-level synthesis of target products.

Purpose: To describe the prevalence and analyse the associated factors of possible sarcopenia and sarcopenia among community-dwelling old adults in China, in order to provide effective strategies for early prevention and treatment of sarcopenia.Methods: This cross-sectional study evaluated community-dwelling old adults aged over 60 years. The basic information, morphological indices, body composition, physical activities were collected and assessed. Possible sarcopenia and sarcopenia were diagnosed by the criteria of Asian Working Group for Sarcopenia (AWGS) in 2019. A multivariate logistic regression model with stepwise method was employed to identify factors associated with possible sarcopenia and sarcopenia.Results: In total 729 old adults from Tianjin were included in this study. 81 participants were diagnosed with possible sarcopenia (prevalence of 11.11%). 75 participants were diagnosed with sarcopenia (prevalence of 10.29%). Age (odds ratio (OR):1.047, 95% confidence interval (CI): 1.055-1.090) and lower physical activities (low level OR:4.171, 95% CI:1.790-9.720; medium level OR:2.634, 95% CI:1.352-5.132) were significantly associated with possible sarcopenia. Age (OR:1.187, 95% CI:1.124-1.253), higher body fat percentage (OR:1.225, 95% CI:1.140-1.317), lower BMI (OR:0.424, 95% CI:0.346-0.519), lower mini-mental state examination (MMSE) scores (OR:0.865,95% CI:0.781-0.958) and low physical activities (OR:4.638, 95% CI:1.683-12.782) were significantly associated with sarcopenia.Conclusion: Possible sarcopenia and sarcopenia are prevalent among community-dwelling old adults in China. Ageing and lower physical activities were both associated with possible sarcopenia and sarcopenia. Old adults with sarcopenia more likely have higher body fat percentage, lower BMI and lower cognitive function compared with those without this condition.

Fomitopsis is a worldwide brown-rot fungal genus of Polyporales, which grows on different gymnosperm and angiosperm trees and has important ecological functions and economic values. In this study, species diversity, phylogenetic relationships, and ecological habits of Fomitopsis were investigated. A total of 195 specimens from 24 countries representing 29 species of Fomitopsis were studied. Based on the morphological characters and phylogenetic evidence of DNA sequences including the internal transcribed spacer (ITS) regions, the large subunit of nuclear ribosomal RNA gene (nLSU), the small subunit of nuclear ribosomal RNA gene (nSSU), the small subunit of mitochondrial rRNA gene (mtSSU), the translation elongation factor 1-α gene (TEF), and the second subunit of RNA polymerase II (RPB2), 30 species are accepted in Fomitopsis, including four new species: F. resupinata, F. srilankensis, F. submeliae and F. yimengensis. Illustrated descriptions of the novel species and the geographical locations of the Fomitopsis species are provided.

The basic helix-loop-helix (

Heteroatom doping can effectively tailor the local structures and electronic states of intrinsic two-dimensional materials, and endow them with modified optical, electrical, and mechanical properties. Recent studies have shown the feasibility of preparing doped graphene from graphene oxide and its derivatives via some post-treatments, including solid-state and solvothermal methods, but they require reactive and harsh reagents. However, direct synthesis of various heteroatom-doped graphene in larger quantities and high purity through bottom-up methods remains challenging. Here, we report catalyst-free and solvent-free direct synthesis of graphene doped with various heteroatoms in bulk via flash Joule heating (FJH). Seven types of heteroatom-doped flash graphene (FG) are synthesized through millisecond flashing, including single-element-doped FG (boron, nitrogen, oxygen, phosphorus, sulfur), two-element

In this study, phylogenetic analyses of

Rapid detection of toxic and hazardous gases at trace concentrations plays a vital role in industrial, battlefield, and laboratory scenarios. Of interest are both sensitive as well as highly selective sensors. Whispering gallery mode (WGM) microresonator-based biochemical sensors are among the most sensitive sensors in existence due to their long photon confinement times. One main concern with these devices, however, is their selectivity towards specific classes of target analytes. Here, we employ frequency locked whispering gallery mode microtoroid optical resonators covalently modified with various polymer coatings to selectively detect the chemical warfare agent surrogate diisopropyl methylphosphonate (DIMP) as well as the toxic industrial chemicals formaldehyde and ammonia at parts-per-trillion concentrations. This is 1-2 orders of magnitude better than previously reported, depending on the target, except for pristine graphene and pristine carbon nanotube sensors, which demonstrate similar detection levels but in vacuum and without selectivity. Selective polymer coatings include polyethylene glycol (PEG) for DIMP sensing, accessed by the modification of commercially available materials, and 3-(triethoxysilyl)propyl-terminated polyvinyl acetate (PVAc) for ammonia sensing. Notably, we developed an efficient one-pot procedure to access 3-(triethoxysilyl)propyl-terminated PVAc that utilizes cobalt-mediated living radical polymerization and a nitroxyl polymer-terminating agent. Alkaline hydrolysis of PVAc coatings to form polyvinyl alcohol (PVA) coatings directly bound to the microtoroid proved to be reliable and reproducible, leading to WGM sensors capable of the rapid and selective detection of formaldehyde vapors. The selectivity of these three polymer coatings as sensing media was predicted, in part, based on their functional group content and known reactivity patterns with the target analytes. Furthermore, we demonstrate that microtoroids coated with a mixture of polymers can serve as an all-in-one sensor that can detect multiple agents. We anticipate that our results will facilitate rapid early detection of chemical agents, as well as their surrogates and precursors.

Five kinds of multi-component entropy-stabilized oxide ceramics were prepared by a solid-state reaction method for thermal barrier coatings, namely La0.125Y0.125Yb0.125Gd0.125Zr0.5O1.75 (LaYYbGdZr), Y0.125Yb0.125Gd0.125Ta0.125Zr0.5O1.875 (YYbGdTaZr), La0.1Y0.1Yb0.1Gd0.1Ta0.1Zr0.5O1.85 (LaYYbGdTaZr), Y0.125Yb0.125Gd0.125Ta0.125Hf0.25Zr0.25O1.875 (YYbGdTaHfZr), and La0.1Y0.1Yb0.1Gd0.1Ta0.1Hf0.25Zr0.25O1.85 (LaYYbGdTaHfZr). Many properties of the materials were studied, such as their microscopic morphology, crystal structure, thermophysical properties, and ablation resistance. The results show that the oxide ceramics synthesized in this paper have a uniform single-phase defect fluorite structure, and can still maintain this structure after high-temperature treatment at 1500 °C. The YYbGdTaHfZr coatings had the lowest thermal conductivity (0.61~0.89 W·m–1·K–1), which was much lower than that of YSZ. The ceramic blocks also exhibited excellent thermal expansion properties. The thermal expansion coefficient of LaYYbGdTaZr could reach 11.09 × 10−6 K−1 (1400 °C), which was slightly higher than that of 8YSZ (11.0 × 10−6 K−1). The antioxidant ablation results proved that the YYbGdTaHfZr coating showed the best heat-insulating property. All the results showed that the YYbGdTaHfZr coating is a promising thermal barrier coating.