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Salinization is a severe threat to agriculture and the environment in many areas, and the same in Qaidam Basin, Qinghai Province, Northwestern China. Microorganisms have an important influence on regulating the biochemical cycles of ecosystems; however, systematic research exploring microbial diversity and interactions with saline-soil ecosystems' environmental variables remains scarce. Thus, 16â¯S rRNA high-throughput sequencing was performed in this paper to characterize microbial diversity under different levels of salinized soils: non-salinized (NS, 2.25â¯g/L), moderately salinized (MS, 6.14â¯g/L) and highly salinized (HS, 9.82â¯g/L). The alpha diversity results showed that the HS soil was significantly different from the NS and MS soils. An analysis of similarity (ANOSIM) and a principal co-ordinates analysis (PCoA) indicated that NS and MS clustered closely while HS separated from the other two. Significant differences in microbial composition were observed at the taxonomic level. Proteobacteria (42.29-79.23â¯%) were the most abundant phyla in the studied soils. Gammaproteobacteria (52.49 and 66.61â¯%) had higher abundance in the MS and HS soils at the class level; Methylophaga and Pseudomonas were the predominant bacteria in the HS soil; and Azotobacter and Methylobacillus were abundant in the MS soil. Most genera belonging to Proteobacteria and Actinobacteria were detected via a linear discriminate analysis (LDA) effect size (LEfSe) analysis, which indicated that microbes with the ability to degrade organic matter and accomplish nutrient cycling can be well-adapted to salt conditions. Further analyses (redundancy analysis and Mantel test) showed that the microbial communities were mainly related to the soil salinity, electrical conductivity (EC1:5), total phosphorus (TP) and ammonia nitrogen (NH4+-N). Overall, the findings of the study can provide insights for better understanding the dominant indigenous microbes and their roles in biochemical cycles in different saline soils in the Qaidam Basin, Qinghai Province, China. The researches related to microbial community under typical poplar species should further clarify the mechanism of plant-microbial interaction and benefit for microbial utilization in salt soil remediation.
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Populus , Salinidad , Microbiología del Suelo , Suelo , China , Populus/microbiología , Suelo/química , Microbiota , ARN Ribosómico 16S/genética , Bacterias/clasificación , Bacterias/genética , EcosistemaRESUMEN
Polaritons, hybrid light and matter waves, offer a platform for subwavelength on-chip light manipulation. Recent works on planar refraction and focusing of polaritons all rely on heterogeneous components with different refractive indices. A fundamental question, thus, arises whether it is possible to configure two-dimensional monolithic polariton lenses based on a single medium. Here, we design and fabricate a type of monolithic polariton lens by directly sculpting an individual hyperbolic van der Waals crystal. The in-plane polariton focusing through sculptured step-terraces is triggered by geometry-induced symmetry breaking of momentum matching in polariton refractions. We show that the monolithic polariton lenses can be robustly tuned by the rise of van der Waals terraces and their curvatures, achieving a subwavelength focusing resolution down to 10% of the free-space light wavelength. Fusing with transformation optics, monolithic polariton lenses with gradient effective refractive indices, such as Luneburg lenses and Maxwell's fisheye lenses, are expected by sculpting polaritonic structures with gradually varied depths. Our results bear potential in planar subwavelength lenses, integrated optical circuits, and photonic chips.
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Aim: Our goal was to explore the prognostic value of the neutrophil-to-hemoglobin ratio (NHR) in HBV-related decompensated cirrhosis (HBV-DC) patients. Methods: 172 HBV-DC patients were enrolled. Multivariate analyses were used to identify risk factors influencing 30-day mortality. Results: The 30-day mortality was 12.8% (22/172). nonsurvivors exhibited a higher NHR than survivors. On multivariate analysis, NHR and model for end-stage liver disease (MELD) score were the only independent predictors of mortality. Notably, the predictive capabilities of NHR were found to be comparable to those of the MELD score. Conclusion: High NHR was associated with poor prognosis in HBV-DC patients, and NHR can serve as an effective and readily available indicator for the prediction of mortality in these patients.
[Box: see text].
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Hemoglobinas , Cirrosis Hepática , Neutrófilos , Humanos , Masculino , Femenino , Cirrosis Hepática/sangre , Cirrosis Hepática/mortalidad , Cirrosis Hepática/complicaciones , Cirrosis Hepática/virología , Persona de Mediana Edad , Hemoglobinas/metabolismo , Hemoglobinas/análisis , Adulto , Pronóstico , Virus de la Hepatitis B , Hepatitis B/complicaciones , Hepatitis B/sangre , Hepatitis B/mortalidad , Anciano , Factores de RiesgoRESUMEN
Recently, many topological materials have been discovered as promising electrocatalysts in chemical conversion processes and energy storage. However, it remains unclear how the topological electronic states specifically modulate the catalytic reaction. Here, the two-dimensional metal phthalocyanine-based covalent organic framework (MPc-COF) is studied by ab initio thermodynamic calculations to clearly reveal the promotional effect on the electrochemical hydrogen evolution reaction (HER) induced by topological gapless bands (TGBs). We find that the prehydrogenated (and fluorinated) H4CdPc-COF(F) shows the best HER performance, with 0.016 V (near zero) overpotential. By tracking changes to the electronic structure and free energy as the prehydrogenation and HER processes occur, we are able to separately attribute the high HER efficiency in part due to the increase of the electron bath by donating electrons to the conjugated π bonds and also to the existence of TGBs. Specifically, the significant catalytic promotion by TGBs is proven to decrease the free energy by 0.218 eV to near zero. When the TGBs are destroyed, e.g., by replacing N with P and opening a band gap, the HER efficiency is reduced. This study opens avenues for deterministically harnessing topological band features to improve electrocatalysis.
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Acute pancreatitis (AP) is among the most common hospital gastrointestinal diagnoses; understanding the mechanisms underlying the severity of AP is critical for development of new treatment options for this disease. Here, we evaluate the biological function of phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3) in AP pathogenesis in 2 independent genetically engineered mouse models of AP. PFKFB3 was elevated in AP and severe AP (SAP), and KO of Pfkfb3 abrogated the severity of alcoholic SAP (FAEE-SAP). Using a combination of genetic, pharmacological, and molecular studies, we defined the interaction of PFKFB3 with inositol 1,4,5-trisphosphate receptor (IP3R) as a key event mediating this phenomenon. Further analysis demonstrated that the interaction between PFKFB3 and IP3R promotes FAEE-SAP severity by altering intracellular calcium homeostasis in acinar cells. Together, our results support a PFKFB3-driven mechanism controlling AP pathobiology and define this enzyme as a therapeutic target to ameliorate the severity of this condition.
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Células Acinares , Calcio , Receptores de Inositol 1,4,5-Trifosfato , Pancreatitis , Fosfofructoquinasa-2 , Animales , Fosfofructoquinasa-2/metabolismo , Fosfofructoquinasa-2/genética , Ratones , Pancreatitis/metabolismo , Pancreatitis/genética , Pancreatitis/patología , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Receptores de Inositol 1,4,5-Trifosfato/genética , Calcio/metabolismo , Células Acinares/metabolismo , Células Acinares/patología , Ratones Noqueados , Modelos Animales de Enfermedad , Índice de Severidad de la Enfermedad , Masculino , Humanos , Señalización del Calcio/genéticaRESUMEN
Drug clearance in obese subjects varies widely among different drugs and across subjects with different severity of obesity. This study investigates correlations between plasma clearance (CLp) and drug- and patient-related characteristics in obese subjects, and evaluates the systematic accuracy of common weight-based dosing methods. A physiologically-based pharmacokinetic (PBPK) modeling approach that uses recent information on obesity-related changes in physiology was used to simulate CLp for a normal-weight subject (body mass index [BMI] = 20) and subjects with various severities of obesity (BMI 25-60) for hypothetical hepatically cleared drugs with a wide range of properties. Influential variables for CLp change were investigated. For each drug and obese subject, the exponent that yields perfect allometric scaling of CLp from normal-weight subjects was assessed. Among all variables, BMI and relative changes in enzyme activity resulting from obesity proved highly correlated with obesity-related CLp changes. Drugs bound to α1-acid glycoprotein (AAG) had lower CLp changes compared to drugs bound to human serum albumin (HSA). Lower extraction ratios (ER) corresponded to higher CLp changes compared to higher ER. The allometric exponent for perfect scaling ranged from -3.84 to 3.34 illustrating that none of the scaling methods performed well in all situations. While all three dosing methods are generally systematically accurate for drugs with unchanged or up to 50% increased enzyme activity in subjects with a BMI below 30 kg/m2, in any of the other cases, information on the different drug properties and severity of obesity is required to select an appropriate dosing method for individuals with obesity.
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Índice de Masa Corporal , Modelos Biológicos , Obesidad , Humanos , Obesidad/metabolismo , Tasa de Depuración Metabólica/fisiología , Preparaciones Farmacéuticas/metabolismo , Preparaciones Farmacéuticas/administración & dosificación , Hígado/metabolismo , Orosomucoide/metabolismo , Albúmina Sérica Humana/metabolismo , Albúmina Sérica Humana/análisis , Masculino , AdultoRESUMEN
Extensive investigations on the moiré magic angle in twisted bilayer graphene have unlocked the emerging field-twistronics. Recently, its optics analogue, namely opto-twistronics, further expands the potential universal applicability of twistronics. However, since heat diffusion neither possesses the dispersion like photons nor carries the band structure as electrons, the real magic angle in electrons or photons is ill-defined for heat diffusion, making it elusive to understand or design any thermal analogue of magic angle. Here, we introduce and experimentally validate the twisted thermotics in a twisted diffusion system by judiciously tailoring thermal coupling, in which twisting an analog thermal magic angle would result in the function switching from cloaking to concentration. Our work provides insights for the tunable heat diffusion control, and opens up an unexpected branch for twistronics -- twisted thermotics, paving the way towards field manipulation in twisted configurations including but not limited to fluids.
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Besides be affected by coal confining pressure, coal seams are also be affected by the surrounding pressure during mining. To understand the heat release characteristics and microstructural evolution of oxidization within coal under different gas pressures is of great significance. For this reason, a combination of theoretical research and test analysis was adopted, which includes differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR) and mercury intrusion method (MIP). The influences of gas phase transformation and migration on the oxidation and spontaneous combustion processes of gas-containing coal under different gas pressures were explored. The distributions and variations in heat release, gas derivation, pore structure and functional group characteristics during the oxidation of gas-containing coal were analysed. We clarified the cross-coupling attributes of heat, seepage and chemical properties in the oxidation of gas-containing coal. The experimental results show that the methane within coal migrates outward in pores with the increase of temperature, which inhibits the penetration and adsorption of oxygen, thereby inhibiting the coaloxygen composite reaction and delaying the heat accumulation within coal. There is a positive correlation between loose and porous characteristics of coal and gas pressure. With the continuous increase of coal temperature, the pore connectivity of high-pressure gas-containing coal is enhanced, which increases the risk of coal spontaneous combustion. The research results are of great significance to the theoretical research on the prevention and prediction of spontaneous combustion of gas-containing coal.
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The transcription factor, signal transducer, and stimulator of transcription 3 (STAT3) is a potential target in osteoarthritis (OA) treatment. Although xanthatin (XA), a biologically active substance derived from Xanthium strumarium L, specifically inhibits STAT3 phosphorylation at Tyr705, the mechanism underlying its inhibitory effect on OA progression remains unclear. In this study, our objective was to explore the therapeutic effects exerted by XA on OA and the underlying molecular mechanisms. The effects of XA treatment on mouse OA models subjected to destabilization of the medial meniscus using medial collateral ligament transection, as well as on interleukin-1ß (IL-1ß)-induced mouse chondrocytes, were examined. Histological changes in cartilage and subchondral bone (SCB), as well as changes in the expression levels of osteophytes, cartilage degeneration- and osteoclast differentiation-related factors, and the role of XA-related signaling pathways in human cartilage tissue, were studied using different techniques. XA inhibited STAT3 phosphorylation at Tyr705 and further attenuated the activity of nuclear factor-κB (NF-κB) in chondrocytes and osteoclasts. In vitro, XA administration alleviated pro-inflammatory cytokine release, extracellular matrix catabolism, and RANKL-mediated osteoclast differentiation. In vivo, intraperitoneal injection of XA exerted a protective effect on cartilage degeneration and SCB loss. Similarly, XA exerted a protective effect on human cartilage tissue by inhibiting the STAT3/NF-κB signaling pathway. Overall, our study elucidated the therapeutic potential of XA as a small-molecule inhibitor of STAT3-driven OA progression. This discovery may help enhance innovative clinical interventions against OA.
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Condrocitos , Progresión de la Enfermedad , Furanos , Ratones Endogámicos C57BL , FN-kappa B , Osteoartritis , Factor de Transcripción STAT3 , Transducción de Señal , Animales , Factor de Transcripción STAT3/metabolismo , Osteoartritis/tratamiento farmacológico , Osteoartritis/patología , Osteoartritis/metabolismo , Transducción de Señal/efectos de los fármacos , FN-kappa B/metabolismo , Humanos , Ratones , Condrocitos/efectos de los fármacos , Condrocitos/metabolismo , Condrocitos/patología , Masculino , Fosforilación/efectos de los fármacos , Modelos Animales de Enfermedad , Osteoclastos/efectos de los fármacos , Osteoclastos/metabolismoRESUMEN
The magnetic type-II Weyl semimetal (MWSM) Co3Sn2S2 has recently been found to host a variety of remarkable phenomena including surface Fermi-arcs, giant anomalous Hall effect, and negative flat band magnetism. However, the dynamic magnetic properties remain relatively unexplored. Here, we investigate the ultrafast spin dynamics of Co3Sn2S2 crystal using time-resolved magneto-optical Kerr effect and reflectivity spectroscopies. We observe a transient magnetization behavior, consisting of spin-flipping dominated fast demagnetization, slow demagnetization due to overall half-metallic electronic structures, and an unexpected ultrafast magnetization enhancement lasting hundreds of picoseconds upon femtosecond laser excitation. By combining temperature-, pump fluence-, and pump polarization-dependent measurements, we unambiguously demonstrate the correlation between the ultrafast magnetization enhancement and the Weyl nodes. Our theoretical modelling suggests that the excited electrons are spin-polarized when relaxing, leading to the enhanced spin-up density of states near the Fermi level and the consequently unusual magnetization enhancement. Our results reveal the unique role of the Weyl properties of Co3Sn2S2 in femtosecond laser-induced spin dynamics.
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Metastasis causes most cancer-related deaths, and the role and mechanism of periostin (POSTN) in the metastasis of hepatocellular carcinoma (HCC) remain undiscovered. In this study, DEN and HTVi HCC models were performed in hepatic-specific Postn ablation and Postn knock-in mouse to reveal the role of POSTN in HCC metastasis. Furthermore, POSTN was positively correlated with circulating EPCs level and promoted EPC mobilization and tumour infiltration. POSTN also mediated the crosstalk between HCC and EPCs, which promoted metastasis ability and upregulated CD36 expression in HCC through indirect crosstalk. Chemokine arrays further revealed that hepatic-derived POSTN induced elevated CCL2 expression and secretion in EPCs, and CCL2 promoted prometastatic traits in HCC. Mechanistic studies showed that POSTN upregulated CCL2 expression in EPCs via the αvß3/ILK/NF-κB pathway. CCL2 further induced CD36 expression via the CCR2/STAT3 pathway by directly binding to the promoter region of CD36. Finally, CD36 was verified to have a prometastatic role in vitro and to be correlated with POSTN expression, metastasis and recurrence in HCC in clinical samples. Our findings revealed that crosstalk between HCC and EPCs is mediated by periostin/CCL2/CD36 signalling which promotes HCC metastasis and emphasizes a potential therapeutic strategy for preventing HCC metastasis.
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Antígenos CD36 , Carcinoma Hepatocelular , Quimiocina CCL2 , Células Progenitoras Endoteliales , Neoplasias Hepáticas , Periostina , Animales , Ratones , Carcinoma Hepatocelular/patología , Células Progenitoras Endoteliales/metabolismo , Células Progenitoras Endoteliales/patología , Neoplasias Hepáticas/patología , Transducción de Señal/genética , Microambiente Tumoral/genética , Quimiocina CCL2/metabolismo , Antígenos CD36/metabolismoRESUMEN
Auxins and their analogs are widely used to promote root growth, flower and fruit development, and yield in crops. The action characteristics and application scope of various auxins are different. To overcome the limitations of existing auxins, expand the scope of applications, and reduce side effects, it is necessary to screen new auxin analogs. Here, we identified 3,4-dichlorophenylacetic acid (Dcaa) as having auxin-like activity and acting through the auxin signaling pathway in plants. At the physiological level, Dcaa promotes the elongation of oat coleoptile segments, the generation of adventitious roots, and the growth of crop roots. At the molecular level, Dcaa induces the expression of auxin-responsive genes and acts through auxin receptors. Molecular docking results showed that Dcaa can bind to auxin receptors, among which TIR1 has the highest binding activity. Application of Dcaa at the root tip of the DR5:GUS auxin-responsive reporter induces GUS expression in the root hair zone, which requires the PIN2 auxin efflux carrier. Dcaa also inhibits the endocytosis of PIN proteins like other auxins. These results provide a basis for the application of Dcaa in agricultural practices.
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Proteínas de Arabidopsis , Arabidopsis , Ácidos Indolacéticos/farmacología , Ácidos Indolacéticos/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Simulación del Acoplamiento Molecular , Raíces de Plantas/metabolismoRESUMEN
The Z4 symmetry indicator is widely used to classify topological materials hosting inversion symmetry. We find orthorhombic Li2AuBi in space group Cmcm is a topological insulator with Z4=1 under no strain via first-principles calculations. Due to small band gaps in the kz = 0 plane, the band inversions can be selectively induced by moderate external strains to realize phases covering all values of Z4 = 1, 2, 3, and 0. Detailed Z4 phase diagrams are plotted under various moderate strains. The (001) surface states and their associated Fermi surfaces and spin textures are calculated. The topological surface states have different connectivities and different spin textures for the four different Z4 phases. The tunability of topological surface states via moderate strain suggests Li2AuBi as an attractive topological material for device applications.
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An electrochemical hydrogen atom transfer (HAT) strategy for the direct amino-α-C-H heteroarylation of amides is described. The cheap TMSN3 acts as a hydrogen atom transfer reagent. A series of heteroarenes including quinoxalin-2(1H)-ones, 4-methylquinoline, isoquinoline, 2-methylquinoxaline, benzothiazole, etc., and various readily available amides/lactams were suitable. The reaction has the characteristics of a wide range of substrates, good regioselectivity, chemical oxidant-free conditions, etc.
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The inability to process many covalent organic frameworks (COFs) as thin films plagues their widespread utilization. Herein, a vapor-phase pathway for the bottom-up synthesis of a class of porphyrin-based COFs is presented. This approach allows integrating electrocatalysts made of metal-ion-containing COFs into the electrodes' architectures in a single-step synthesis and deposition. By precisely controlling the metal sites at the atomic level, remarkable electrocatalytic performance is achieved, resulting in unprecedentedly high mass activity values. How the choice of metal atoms, i.e., cobalt and copper, can determine the catalytic activities of POR-COFs is demonstrated. The theoretical data proves that the Cu site is highly active for nitrate conversion to ammonia on the synthesized COFs.
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T0001 is the first mutant of etanercept with a higher affinity to tumor necrosis factor α (TNF-α) than etanercept. In order to investigate the safety and tolerability of T0001, a study was carried out in healthy Chinese subjects. A first-in-human, dose escalation study was conducted in healthy Chinese subjects. Fifty-six subjects were divided into six dose cohorts (10 mg, 20 mg, 35 mg, 50 mg, 65 mg and 75 mg) to receive a single subcutaneous injection of T0001. Safety and tolerability assessment were based on the records of vital signs, physical examinations, clinical laboratory tests, 12-lead electrocardiograms and adverse events (AEs). All subjects were in good compliance and none withdraw due to AEs. No serious AEs occurred. A total of twenty-three AEs in sixteen subjects were recorded, and eighteen of these AEs were believed to be related to T0001. The most frequently reported AEs were injection site reactions and white blood cell count increase. All these AEs were of mild to moderate intensity and most of them recovered spontaneously within 14 days. In this study, no dose-limiting toxicity was observed, and the maximum tolerated dose was identified as 75 mg. T0001 was considered safe and generally well tolerated at doses up to 75 mg in healthy Chinese volunteers