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Appropriate capillary effects are beneficial for controlling the wet powder performance and agglomerate formation. As water content rises, the funicular regime supplants the pendular regime as the predominant state in wet granular media. The displacement of grains leading to the stretching of funicular liquid bridges until rupture is an interesting and common phenomenon. Utilizing Surface Evolver software (an energy minimization approach), this work develops an efficient and accurate numerical model to describe liquid interactions among three spherical grains. The effects of liquid volume, contact angle, grain size ratio, grain-pair gap, and separation distance on the capillary forces and rupture distances are investigated. Notably, we present a modified closed-form equation for predicting the rupture distance of funicular bridges between three grains, which reflects the coupled effects of the contact angle, grain size, and liquid volume on rupture distance. This present study provides insights for incorporating capillary effects into mechanical models relying on microassembly composed of several grains in bidisperse particulate systems. Additionally, the numerical findings confirm some findings regarding the splitting of funicular bridges.
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A practical synthesis of valuable N-acyl anthranilic acids has been achieved via a silver-catalyzed imino-ketene generation from readily available anthranils and carboxylic acids. A wide range of carboxylic acids including sterically demanding aliphatic carboxylic acids, aromatic carboxylic acids, acrylic acids, and amino acids are compatible in this reaction. Moreover, this method can be used to modify drug molecules and natural products, such as ibuprofen, probenecid, and acetylglycine.
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The combined cadmium (Cd) and acid rain pollution poses a significant threat to the global ecological environment. Previous studies on the combined adverse effects have predominantly focused on the aboveground plant physiological responses, with limited reports on the microbial response in the rhizosphere soil. This study employed Populus beijingensis seedlings and potting experiments to simulate the impacts of combined mild acid rain (pH=4.5, MA) or highly strong acid rain (pH=3.0, HA), and soil Cd pollution on the composition and diversity of microbial communities, as well as the physiochemical properties in the rhizosphere soil. The results showed that Cd decreased the content of inorganic nitrogen, resulting in an overall decrease of 49.10â¯% and 46.67â¯% in ammonium nitrogen and nitrate nitrogen, respectively. Conversely, acid rain was found to elevate the content of total potassium and soil organic carbon by 4.68â¯%-6.18â¯% and 8.64-19.16â¯%, respectively. Additionally, simulated acid rain was observed to decrease the pH level by 0.29-0.35, while Cd increased the pH level by 0.11. Moreover, Cd alone reduced the rhizosphere bacterial diversity, however, when combined with acid rain, regardless of its intensity, Cd was observed to increase the diversity. Fungal diversity was not influenced by the acid rain, but Cd increased fungal diversity to some extend under HA as observed in bacterial diversity. In addition, composition of the rhizosphere bacterial community was primarily influenced by the inorganic nitrogen components, while the fungal community was driven mainly by soil pH. Furthermore, "Metabolism" was emerged as the most significant bacterial function, which was markedly affected by the combined pollution, while Cd pollution led to a shift from symbiotroph to other trophic types for fungi. These findings suggest that simulated acid rain has a mitigating effect on the diversity of rhizosphere bacteria affected by Cd pollution, and also alters the trophic type of these microorganisms. This can be attributed to the acid rain-induced direct acidic environment, as well as the indirect changes in the availability or sources of carbon, nitrogen, or potassium.
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Chuva Ácida , Cádmio , Nitrogênio , Populus , Rizosfera , Plântula , Microbiologia do Solo , Poluentes do Solo , Cádmio/toxicidade , Cádmio/análise , Populus/efeitos dos fármacos , Populus/microbiologia , Populus/crescimento & desenvolvimento , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/microbiologia , Nitrogênio/análise , Solo/química , Microbiota/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacosRESUMO
Background: Non-small cell lung cancer (NSCLC) is the most prevalent malignant tumor of the lung cancer, for which the molecular mechanisms remain unknown. In this study, we identified novel biomarkers associated with the pathogenesis of NSCLC aiming to provide new diagnostic and therapeutic approaches for NSCLC by bioinformatics analysis. Methods: From the Gene Expression Omnibus database, GSE118370 and GSE10072 microarray datasets were obtained. Identifying the differentially expressed genes (DEGs) between lung adenocarcinoma and normal samples was done. By using bioinformatics tools, a protein-protein interaction (PPI) network was constructed, modules were analyzed, and enrichment analyses were performed. The expression and prognostic values of 14 hub genes were validated by the GEPIA database, and the correlation between hub genes and survival in lung adenocarcinoma was assessed by UALCAN, cBioPortal, String and Cytoscape, and Timer tools. Results: We found three genes (PIK3R1, SPP1, and PECAM1) that have a clear correlation with OS in the lung adenocarcinoma patient. It has been found that lung adenocarcinoma exhibits high expression of SPP1 and that this has been associated with poor prognosis, while low expression of PECAM1 and PIK3R1 is associated with poor prognosis (P < 0.05). We also found that the expression of SPP1 was associated with miR-146a-5p, while the high expression of miR-146a-5p was related to good prognosis (P < 0.05). On the contrary, the lower miR-21-5p on upstream of PIK3R1 is associated with a higher surviving rate in cancer patients (P < 0.05). Finally, we found that the immune checkpoint genes CD274(PD-L1) and PDCD1LG2(PD-1) were also related to SPP1 in lung adenocarcinoma. Conclusions: The results indicated that SPP1 is a cancer promoter (oncogene), while PECAM1 and PIK3R1 are cancer suppressor genes. These genes take part in the regulation of biological activities in lung adenocarcinoma, which provides a basis for improving detection and immunotherapeutic targets for lung adenocarcinoma.
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Adenocarcinoma de Pulmão , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Perfilação da Expressão Gênica/métodos , Biomarcadores Tumorais/genética , Adenocarcinoma de Pulmão/genética , Prognóstico , Biologia Computacional/métodos , Regulação Neoplásica da Expressão GênicaRESUMO
An external photocatalyst-free benzylic C-H functionalization with fluorenones under visible-light irradiation has been achieved. This transformation provides an efficient synthetic approach to 9-benzylated fluorenols in ≤91% yield with 100% atom economy under mild conditions. Spectroscopic studies suggest that a reductive quenching of photoexcited fluorenones with toluene derivatives generates ketyl radicals and benzyl radicals, which undergo a cross-coupling to afford the desired fluorenols.
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Different chemoselectivities of phenols and thiophenols were observed in a Tf2O-promoted C3 functionalization of simple anthranils. The reaction of phenols and anthranils gives 3-aryl anthranils via a C-C bond formation, whereas thiophenols afford 3-thio anthranils through a C-S bond formation. Both reactions have a broad substrate scope and tolerate a wide range of functional groups, affording the corresponding products with specific chemoselectivity.
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The traditional hydrolysis-cooling-adsorption process for coke oven gas (COG) desulfurization urgently needs to be improved because of its complex nature and high energy consumption. One promising alternative for replacing the last two steps is selective catalytic oxidation. However, most catalysts used in selective catalytic oxidation require a high temperature to achieve effective desulfurization. Herein, a robust 30Fe-MCM41 catalyst is developed for direct desulfurization at medium temperatures after hydrolysis. This catalyst exhibits excellent stability for over 300 h and a high breakthrough sulfur capacity (2327.6 mgS gcat-1). Introducing Ag into the 30Fe-MCM41 (30Fe5Ag-MCM41) catalyst further enhances the H2S removal efficiency and sulfur selectivity at 120 °C. Its outstanding performance can be attributed to the synergistic effect of Fe-Ag clusters. During H2S selective oxidation, Fe serves as the active site for H2S adsorption and dissociation, while Ag functions as the catalyst promoter, increasing Fe dispersion, reducing the oxidation capacity of the catalyst, improving the desorption capacity of sulfur, and facilitating the reaction between active oxygen species and [HS]. This process provides a potential route for enhancing COG desulfurization.
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Coque , Sulfeto de Hidrogênio , Adsorção , Hidrogênio , Sulfetos , TemperaturaRESUMO
Numerous studies have proved that epithelial-mesenchymal transition (EMT) of lung epithelial cells is one of the important causes of radiation-induced pulmonary fibrosis (RIPF). Aldose reductase (AR) is a monomer enzyme in the polyglycolic metabolic pathway and belongs to the aldo-keno reductase protein superfamily. Our previous studies have found that AR as one of the most significantly up-regulated genes was associated with the development of bleomycin-induced PF in rats. It is not clear whether aldose reductase is related to the regulation of radiation-induced EMT and mediates RIPF. AR-knockout mice, wild-type mice and lung epithelial cells were induced by radiation to establish a RIPF animal model and EMT system, to explore whether AR is mediation to RIPF through the EMT pathway. In vivo, AR deficiency significantly alleviated radiation-induced histopathological changes, reduced collagen deposition and inhibited collagen I, matrix metalloproteinase 2 (MMP2) and Twist1 expression. In addition, AR knockout up-regulated E-cadherin expression and up-regulated α-SMA and Vimentin expression. In vitro, AR, collagen I and MMP2 expression were increased in lung epithelial cells after radiation, which was accompanied by Twist1 expression up-regulation and EMT changes evidenced by decreased E-cadherin expression and increased α-SMA and Vimentin expression. Knockdown or inhibition of AR inhibited the expressions of Twist1, MMP2 and collagen I, and reduced cell migration and reversed radiation-induced EMT. These results indicated that aldose reductase may be related to radiation-induced lung epithelial cells EMT, and that inhibition of aldose reductase might be a promising treatment for RIPF.
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Fibrose Pulmonar , Camundongos , Ratos , Animais , Fibrose Pulmonar/genética , Fibrose Pulmonar/induzido quimicamente , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Vimentina/metabolismo , Aldeído Redutase/genética , Aldeído Redutase/metabolismo , Pulmão/patologia , Colágeno/genética , Colágeno/metabolismo , Caderinas/genética , Caderinas/metabolismo , Transição Epitelial-Mesenquimal/genéticaRESUMO
Non-point source pollution caused by surface runoff has been a popular hydrological and environmental safety issue and has attracted extensive attention from global scholars. To identify the optimal vegetation coverage of Festuca arundinacea grassland for controlling soil erosion and purifying surface runoff, bare land was chosen as the control in this experiment. Simulated rainfall experiments were carried out with three levels of coverage (low coverage, moderate coverage and full coverage) under four slope conditions (flat slope, gentle slope, medium slope, and steep slope) and at four rainfall intensities (moderate rainfall, heavy rainfall, rainstorm and heavy rainstorm). The comprehensive evaluation results suggested that the capacity of Festuca arundinacea grassland for reducing the surface runoff, sediment yield, suspended solids (SS), total nitrogen (TN), total phosphorus (TP) and chemical oxygen demand (COD) decreased with increasing rainfall intensity and slope but increased with increasing vegetation coverage. Structural equation model (SEM) results suggested that there were positive relationships between the vegetation coverage and purification capacity index and negative correlations between the rainfall intensity and slope and the purification capacity index. The response surface analysis results suggested that the optimal vegetation coverage should be higher than 84% and that the slope should be smaller than 10° for controlling soil erosion and avoiding pollution via diffusion with surface runoff in Festuca arundinacea grassland. This study proposes recommendations for the vegetation configuration pattern in the development and management of runoff purification systems.
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Conservação dos Recursos Hídricos , Poluição Difusa , China , Monitoramento Ambiental/métodos , Pradaria , Chuva , Solo , Movimentos da ÁguaRESUMO
A three-component reaction involving arynes, trialkyl phosphites, and halides has been achieved under mild reaction conditions. This transformation provides a direct synthetic approach to ortho-halogenated arylphosphonates, which could be rapidly converted to diversely ortho-functionalized arylphosphorus compounds.
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A nickel-catalyzed polarity-reversed hydroamination of olefins has been achieved with anthranils as the electrophilic aminating agents and hydrosilane as the reductant. This protocol provides a facile access to N-alkyl-2-aminobenzophenones that are versatile intermediates in organic synthesis. A wide range of olefins and anthranils are compatible in this transformation, delivering the desired amines in useful to excellent yields (38 examples, up to 92% yield). The utility of this protocol is exhibited in the late-stage functionalization of drug molecules and the valuable derivatives of the obtained amination products.
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Alcenos , Níquel , Aminação , Catálise , Cobre , IsoxazóisRESUMO
A novel three-component reaction of arynes, sodium sulfinates, and aldehydes under mild reaction conditions is described. This transformation provides a direct synthetic approach to 2-sulfonyl benzyl alcohol derivatives, which could be rapidly converted to diverse arylsulfur compounds via the transformation of the corresponding hydroxyl groups. Various aryne precursors, sodium arenesulfinates, and aromatic aldehydes can be effectively converted to the desired products in 40-84% yields (29 examples).
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This study aimed to assess whether chrysin(ChR) can inhibit epithelial-mesenchymal transition(EMT) of type â ¡ alveolar epithelial cell and produce anti-pulmonary fibrosis effect by regulating the NF-κB/Twist 1 signaling pathway. Sixty rats were randomly divided into the control group, the bleomycin(BLC) group, BLC+ChR(50 mg·kg~(-1)) group and BLC+ChR(100 mg·kg~(-1)) group, with 15 rats in each group. The pulmonary fibrosis model was induced by intratracheal injection of BLC(7 500 U·kg~(-1)). Rats were orally administered with different doses of ChR after BLC injection for 28 days. The cells were divided into control group, TGF-ß1 group(5 ng·mL~(-1)), and TGF-ß1+ChR(1, 10, 100 µmol·L~(-1)) groups. The type â ¡ alveolar epithelial cells were treated with TGF-ß1 for 24 h, and then treated with TGF-ß1 for 48 h in the presence or absence of different doses of ChR(1, 10 and 100 µmol·L~(-1)). The morphological changes and collagen deposition in lung tissues were analyzed by HE staining, Masson staining and immunohistochemistry. The mRNA and protein expression levels of collagen â , E-cadherin, zonula occludens-1(ZO-1), vimentin, alpha smooth muscle actin(α-SMA), inhibitor of nuclear factor kappa B alpha(IκBα), nuclear factor-kappa B p65(NF-κB p65), phospho-NF-κB p65(p-p65) and Twist 1 in lung tissues and cells were detected by qPCR and Western blot, respectively. The animal experiment results showed that as compared with the BLC group, after administration of ChR for 28 days, bleomycin-induced pulmonary fibrosis in rats was significantly relieved, collagen â expression in lung tissues was significantly reduced(P<0.05 or P<0.01), and EMT of alveolar epithelial cells was obviously inhibited [the expression levels of E-cadherin and ZO-1 were increased and the expression levels of vimentin and α-SMA were decreased(P<0.05 or P<0.01)], concomitantly with significantly reduced IκBα and p65 phosphorylation level in cytoplasm and decreased NF-κB p65 and Twist 1 expression in nucleus(P<0.05 or P<0.01). The cell experiment results showed that different doses of ChR(1, 10 and 100 µmol·L~(-1)) significantly reduced TGF-ß1-induced collagen â expression(P<0.05 or P<0.01), significantly inhibited EMT of type â ¡ alveolar epithelial cells[the expression levels of E-cadherin and ZO-1 were increased and the expression levels of vimentin and α-SMA were decreased(P<0.05 or P<0.01)], and inhibited IκBα and p65 phosphorylation in cytoplasm and down-regulated NF-κB p65 and Twist 1 expression in nucleus induced by TGF-ß1(P<0.05 or P<0.01). The results suggest that ChR can reverse EMT of type â ¡ alveolar epithelial cell and alleviate pulmonary fibrosis in rats, and its mechanism may be associated with reducing IκBα phosphorylation and inhibiting NF-κB p65 phosphorylation and nuclear transfer, thus down-regulating Twist 1 expression.
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Transição Epitelial-Mesenquimal , NF-kappa B , Células Epiteliais Alveolares/metabolismo , Animais , Flavonoides , NF-kappa B/genética , NF-kappa B/metabolismo , Ratos , Transdução de Sinais , Fator de Crescimento Transformador beta1/genéticaRESUMO
A direct and practical metal-free N-H phosphorylation has been achieved via the TBHP/NH4I-mediated cross-dehydrogenative coupling (CDC) reactions between imines/imidates and P(O)H compounds. This transformation provides an efficient synthetic route to the construction of P-N bonds with good functional group compatibility, leading to the formation of N-phosphorylimines and N-phosphorylimidates in up to 95% yield (33 examples) under mild conditions.
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The forest gap crucially influences forest environments, but its effects on local fungal community assembly are not fully understood. In this study, the fungal community in a weeping cypress forest was investigated as a function of forest gap locations based on forest clearing, using amplicon sequencing of the ITS2 region. The results showed that the fungal community significantly varied with the variations in soil properties related to gap location. Deterministic processes played pivotal roles in fungal community assembly, which was mainly driven by the temperature, moisture, available nitrogen, and microbial carbon in soil. Beta diversity of the fungal community increased from the gap center to the closed canopy. The relative abundances of dominant orders such as Microascales, Sordariales, and Chaetothyriales regularly varied as a function of gap location, and they were potential indicators for different gap locations. Based on network analysis, gap locations caused distinct co-occurrence patterns of fungal communities. This study shed light on the roles of forest gaps in the assembly of local fungal communities and provided additional strategies to manage forest ecosystems.
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Florestas , Fungos/fisiologia , Micobioma/fisiologia , Microbiologia do Solo , Biodiversidade , Carbono/metabolismo , Cupressus , DNA Intergênico , Fungos/genética , Micobioma/genética , Nitrogênio/metabolismo , Temperatura , ÁrvoresRESUMO
Iron ore sintering is a major source of gaseous and particulate pollutants emission in iron smelt plant. The aim of present study is to characterize the volatile organic compounds (VOCs) emission profiles from iron ore sintering process. Both sinter pot test and sinter simulation experiment were conducted and compared. Out results showed that sinter process produced large quantity of VOCs together with NOx and SO2. VOCs and NO were produced simultaneously in sinter pot test from 3 to 24 min after ignition, flowed by SO2 production from 15 min to the end of sintering. Total VOCs (TVOC) concentration in sinter flue gas was affected by the coal and coke ratio in sinter raw material. The maximum TVOC concentration was 34.5 ppm when using 100% coal as fuel. Sinter simulation experiments found that the number of VOCs species and their concentrations were found by sinter temperature. The largest VOCs species varieties were obtained at 500 °C. Benzene, toluene, xylene and ethylbenzene were major VOCs in sinter flue gas based on the results from both simulation test and sinter pot. It thus demonstrated that in addition to NOx, SO2 and metal oxide particles, sinter flue gas also contained significant amount of VOCs whose environmental impact cannot be ignored. Based on our work, it is timely needed to establish a new VOC emission standard for sinter flue gas and develop advanced techniques to simultaneously eliminate multi-pollutants in iron ore sinter process.
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Ferro/química , Compostos Orgânicos Voláteis/química , Temperatura Alta , Óxidos/química , Material Particulado/químicaRESUMO
Herein we report a novel palladium-catalyzed oxidative carbonylation reaction for the synthesis of phthalimides with high atom- and step-economy. In our strategy, the imine and H2O, which are generated in situ from the condensation of aldehyde and amine, serve as self-sufficient directing group and nucleophile, respectively. This method provides rapid access to phthalimides starting from readily available materials in a one-pot manner. Various phthalimide derivatives are constructed efficiently, including medicinally and biologically active phthalimide-containing compounds.
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Two novel highly selective quinoline-based fluorescent probes (1 and 2) with an aggregation induced emission (AIE) feature have been designed and synthesized for the rapid analysis of Cu2+ ions in aqueous media and on paper strips with a fluorescence quenching mechanism. Moreover, probes 1 and 2 exhibit excellent sensitivity and anti-interference for Cu2+ detection, and the detection limits are as low as 1.3 × 10-8 M and 8.5 × 10-8 M, respectively, which are much lower than the allowable standard of Cu2+ (â¼20 µM) in drinking water (EPA). More importantly, these two probes were successfully applied for the determination of Cu2+ in real aqueous samples and fabrication of simple device test strips for rapid and on-site detection of Cu2+ ions. Interestingly, they can also be regenerated by adding an excess of S2-. Additionally, the crystallographic structure of probe 1 was confirmed through a single crystal X-ray study. Job's plot analysis and ESI-MS spectroscopic studies reflect the 1 : 1 complexation of the 1-Cu2+ and 2-Cu2+ complexes. Furthermore, DFT/TDDFT calculations were performed in order to help in understanding the electronic properties of the complexes and the chelation-induced quenching mechanism.
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An oxidative cascade that involves multicomponent reaction comprising a terminal alkyne, 2-amino N-heterocycle, benzyl or allylic bromide with molecular oxygen, delivering densely functionalized imidazo fused heterocycles, is described. This reaction features a cheap catalyst, a green oxidant, and readily available starting materials, which make the overall synthesis applicable in the quick access to relevant pharmaceutical molecules with imidazole derived heterocycles.
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The Internet of Things (IoT) is emerging as a new communication paradigm and has attracted a significant amount of attention from both academic and engineering communities. In this paper, we consider an IoT market where three roles exist: Wireless Sensor Networks (WSNs), two service providers (SPs) and end users. The WSNs are responsible for sensing and providing data to the two SPs. Based on the sensed data from WSNs, the two SPs compete to provide services to the end users. We model the relationship between the two SPs and end users as a two-stage Stackelberg game, where the two SPs set the prices for their services firstly, and then the end users decide which SP to choose. Specifically, we consider two price-competition scenarios of the two SPs, which are engaged in two games, one is a noncooperative strategic game (NSG) where the two SPs set the prices for services simultaneously, the other is a Stackelberg game (SG) where SP1 who sets the price first is the leader and SP2 who sets the price after is the follower. Each user decides whether and which SP to purchase services from based on prices and service rates. An equilibrium is achieved in each of the two scenarios. Numerical results are conducted to verify our theoretical analysis.