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Soil organic carbon (SOC) mineralization is a key component of the global carbon cycle. Its temperature sensitivity Q10 (which is defined as the factor of change in mineralization with a 10 °C temperature increase) is crucial for understanding the carbon cycle-climate change feedback but remains uncertain. Here, we demonstrate the universal control of carbon quality-availability tradeoffs on Q10. When carbon availability is not limited, Q10 is controlled by carbon quality; otherwise, substrate availability controls Q10. A model driven by such quality-availability tradeoffs explains 97% of the spatiotemporal variability of Q10 in incubations of soils across the globe and predicts a global Q10 of 2.1 ± 0.4 (mean ± one SD) with higher Q10 in northern high-latitude regions. We further reveal that global Q10 is predominantly governed by the mineralization of high-quality carbon. The work provides a foundation for predicting SOC dynamics under climate and land use changes which may alter soil carbon quality and availability.
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The penetrating growth of Li into the inorganic solid-state electrolyte (SSE) is one key factor limiting its practical application. Research to understand the underlying mechanism of Li penetration has been ongoing for years and is continuing. Here, we report an in situ scanning electron microscopy methodology to investigate the dynamic behaviors of isolated Li filaments in the garnet SSE under practical cycling conditions. We find that the filaments tend to grow in the SSE, while surprisingly, those filaments can self-dissolve with a decrease in the current density without a reversal of the current direction. We further build a coupled electro-chemo-mechanical model to assess the interplay between electrochemistry and mechanics during the dynamic evolution of filaments. We reveal that filament growth is strongly regulated by the competition between the electrochemical driving force and mechanical resistive force. The numerical results provide rational guidance for the design of solid-state batteries with excellent properties.
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Rechargeable hydrogen gas batteries, driven by hydrogen evolution and oxidation reactions (HER/HOR), are emerging grid-scale energy storage technologies owing to their low cost and superb cycle life. However, compared with aqueous electrolytes, the HER/HOR activities in nonaqueous electrolytes have rarely been studied. Here, for the first time, we develop a nonaqueous proton electrolyte (NAPE) for a high-performance hydrogen gas-proton battery for all-climate energy storage applications. The advanced nonaqueous hydrogen gas-proton battery (NAHPB) assembled with a representative V2(PO4)3 cathode and H2 anode in a NAPE exhibits a high discharge capacity of 165 mAh g-1 at 1 C at room temperature. It also efficiently operates under all-climate conditions (from -30 to +70 °C) with an excellent electrochemical performance. Our findings offer a new direction for designing nonaqueous proton batteries in a wide temperature range.
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Gasdermin E (GSDME), a member of the gasdermin protein family, is associated with post-lingual hearing loss. All GSDME pathogenic mutations lead to skipping exon 8; however, the molecular mechanisms underlying hearing loss caused by GSDME mutants remain unclear. GSDME was recently identified as one of the mediators of programmed cell death, including apoptosis and pyroptosis. Therefore, in this study, we injected mice with GSDME mutant (MT) and examined the expression levels to assess its effect on hearing impairment. We observed loss of hair cells in the organ of Corti and spiral ganglion neurons. Further, the N-terminal release from the GSDME mutant in HEI-OC1 cells caused pyroptosis, characterized by cell swelling and rupture of the plasma membrane, releasing lactate dehydrogenase and cytokines such as interleukin-1ß. We also observed that the N-terminal release from GSDME mutants could permeabilize the mitochondrial membrane, releasing cytochromes and activating the mitochondrial apoptotic pathway, thereby generating possible positive feedback on the cleavage of GSDME. Furthermore, we found that treatment with disulfiram or dimethyl fumarate might inhibit pyroptosis and apoptosis by inhibiting the release of GSDME-N from GSDME mutants. In conclusion, this study elucidated the molecular mechanism associated with hearing loss caused by GSDME gene mutations, offering novel insights for potential treatment strategies.
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Apoptose , Piroptose , Piroptose/genética , Animais , Camundongos , Mutação com Ganho de Função , Perda Auditiva/genética , Perda Auditiva/patologia , Humanos , Gânglio Espiral da Cóclea/metabolismo , Gânglio Espiral da Cóclea/patologia , Órgão Espiral/metabolismo , Órgão Espiral/patologia , Células Ciliadas Auditivas/metabolismo , Células Ciliadas Auditivas/patologia , GasderminasRESUMO
A 1D/2D genome-wide association study strategy was adopted to investigate the genetic systems underlying the reciprocal adaptation of rice (Oryza sativa) and its bacterial pathogen, Xanthomonas oryzae pv. oryzae (Xoo) using the whole-genome sequencing and large-scale phenotyping data of 701 rice accessions and 23 diverse Xoo strains. Forty-seven Xoo virulence-related genes and 318 rice quantitative resistance genes (QR-genes) mainly located in 41 genomic regions, and genome-wide interactions between the detected virulence-related genes and QR genes were identified, including well-known resistance genes/virulence genes plus many previously uncharacterized ones. The relationship between rice and Xoo was characterized by strong differentiation among Xoo races corresponding to the subspecific differentiation of rice, by strong shifts toward increased resistance/virulence of rice/Xoo populations and by rich genetic diversity at the detected rice QR-genes and Xoo virulence genes, and by genome-wide interactions between many rice QR-genes and Xoo virulence genes in a multiple-to-multiple manner, presumably resulting either from direct protein-protein interactions or from genetic epistasis. The observed complex genetic interaction system between rice and Xoo likely exists in other crop-pathogen systems that would maintain high levels of diversity at their QR-loci/virulence-loci, resulting in dynamic coevolutionary consequences during their reciprocal adaptation.
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Interações Hospedeiro-Patógeno/genética , Oryza/genética , Oryza/microbiologia , Xanthomonas/genética , Adaptação Fisiológica/genética , Resistência à Doença/genética , Regulação Bacteriana da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genoma Bacteriano , Genoma de Planta , Estudo de Associação Genômica Ampla , Desequilíbrio de Ligação , Filogenia , Melhoramento Vegetal , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Polimorfismo de Nucleotídeo Único , Virulência/genética , Sequenciamento Completo do Genoma , Xanthomonas/patogenicidadeRESUMO
Colorectal cancer (CRC) is a highly invasive malignant tumor with pronounced proliferation capacity and is prone to epithelial-mesenchymal transition (EMT) and subsequent metastasis. A disintegrin and metalloproteinase domain-like decysin 1 (ADAMDEC1) is a proteolytically active metzincin metalloprotease that is involved in extracellular matrix remodeling, cell adhesion, invasion, and migration. However, the effects of ADAMDEC1 on CRC are unclear. This study was conducted to investigate the expression and biological role of ADAMDEC1 in CRC. We found that ADAMDEC1 was differentially expressed in CRC. Further, ADAMDEC1 was found to enhance CRC proliferation, migration, and invasion while inhibiting apoptosis. Exogenous ADAMDEC1 overexpression elicited EMT in CRC cells, as evidenced by alterations in E-cadherin, N-cadherin, and vimentin expression. In ADAMDEC1 knockdown or ADAMDEC1 overexpressed CRC cells, the western blotting analysis revealed that Wnt/ß-catenin signaling pathway-related proteins were down-regulated or up-regulated. Furthermore, an inhibitor of the Wnt/ß-catenin pathway (FH535) partially negated the effect of ADAMDEC1 overexpression on EMT and CRC cell proliferation. Further mechanistic research suggested that ADAMDEC1 knockdown may upregulate GSK-3ß and inactivate the Wnt/ß-catenin pathway, accompanied by suppressing the expression of ß-catenin. Additionally, the blocker of GSK-3ß (CHIR-99021) markedly abolished the inhibitory effect of ADAMDEC1 knockdown on Wnt/ß-catenin signaling. Our results indicate that ADAMDEC1 promotes CRC metastasis by negatively regulating GSK-3ß, activating the Wnt/ß-catenin signaling pathway, and inducing EMT, presenting its potential as a therapeutic target for the treatment of metastatic CRC.
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Neoplasias Colorretais , Via de Sinalização Wnt , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Neoplasias Colorretais/patologia , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismoRESUMO
Pattern recognition receptors are an essential part of the immune system, which detect pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs) and help shape both innate and adaptive immune responses. When dsDNA is present, cyclic GMP-AMP Synthase (cGAS) produces a second messenger called cyclic GMP-AMP (cGAMP), which then triggers an adaptor protein called STING, and eventually activates the expression of type I interferon (IFN) and pro-inflammatory cytokines in immune cells. The cGAS-STING signaling pathway has been receiving a lot of attention lately as a key immune-surveillance mediator. In this review, we summarize the present circumstances of the cGAS-STING signaling pathway in viral infections and inflammatory diseases, as well as autoimmune diseases. Modulation of the cGAS-STING signaling pathway provides potential strategies for treating viral infections, inflammatory diseases, and autoimmune diseases.
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PURPOSE: Colorectal cancer (CRC) is a very common malignancy of the digestive system. Despite a variety of treatments including surgery, chemotherapeutic and targeted drugs, the prognosis for patients with CRC is still unsatisfactory and the mortality remains high. Protein phosphorylation plays an essential role in tumorigenesis and progression and is also crucial for protein to act with proper functions. Ferroptosis is found widely involved in various diseases especially tumors as a newly identified programmed cell death. METHODS: In our study, we aimed at PPP2CA as a prospective target which may play a crucial role in CRC progression. In one hand, knockdown of PPP2CA significantly enhanced the malignant phenotype in HCT116. In the other hand, knockdown of PPP2CA significantly enhanced Erastin-induced ferroptosis as well. RESULTS: Specifically, knockdown of PPP2CA in HCT116 significantly increased the relative level of malondialdehyde (MDA), reactive oxygen species (ROS) and Fe2+, and decreased GSH/GSSG ratio after the treatment of certain concentration of Erastin. Besides, we found that the inhibition of PPP2CA further led to the suppression of SCD1 expression in CRC cells in a AMPK-dependent way. CONCLUSION: Ultimately, we conclude that PPP2CA may regulate Erastin-induced ferroptosis through AMPK/SCD1 signaling pathway.
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Proteínas Quinases Ativadas por AMP , Neoplasias Colorretais , Ferroptose , Proteína Fosfatase 2 , Humanos , Ferroptose/efeitos dos fármacos , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/tratamento farmacológico , Proteína Fosfatase 2/metabolismo , Proteína Fosfatase 2/genética , Células HCT116 , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Transdução de Sinais , Piperazinas/farmacologia , Espécies Reativas de Oxigênio/metabolismoRESUMO
Aluminum (Al) metal is an attractive anode material for next-generation rechargeable batteries, because of its low cost and high capacities. However, it brings some fundamental issues such as dendrites, low Coulombic efficiency (CE), and low utilization. Here, we propose a strategy for constructing an ultrathin aluminophilic interface layer (AIL) to regulate the Al nucleation and growth behaviors, which enables highly reversible and dendrite-free Al plating/stripping under high areal capacity. Metallic Al can maintain stable plating/stripping on the Pt-AIL@Ti for over 2000 h at 10 mAh cm-2 with an average CE of 99.9%. The Pt-AIL also enables reversible Al plating/stripping at a record high areal capacity of 50 mAh cm-2, which is 1-2 orders of magnitude higher than the previous studies. This work provides a valuable direction for further construction of high-performance rechargeable Al metal batteries.
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Milk fat is a premium nutritional health product, yet there is a lack of high-fat dairy products for daily consumption in the current market. This study investigated the influence of different milk fat contents on the physicochemical and textural properties of fermented milk. The research revealed that an increase in milkfat content significantly improved the water-holding capacity, syneresis, color, hardness, springiness, gumminess, and chewiness of fermented milk, while showing minimal changes in pH and total titratable acidity. Response surface analysis indicated that fermented milk with 25% milk fat, 2.5% inoculum, a fermentation time of 16 h, and a fermentation temperature of 30 °C exhibited the highest overall acceptability. Using GC-IMS technology, 36 volatile compounds were identified, with an increase in milk fat content leading to elevated levels of ketone compounds, and 14 compounds were defined as key aroma compounds (ROAV > 1). Electronic nose distinguished samples with different milk fat contents. The results demonstrate that an increase in milk fat content enhances the physicochemical and flavor attributes of fermented milk. This work provides theoretical references for the production and development of high-fat fermented milk.
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Espectrometria de Mobilidade Iônica , Leite , Animais , Leite/química , Cromatografia Gasosa-Espectrometria de Massas , Análise Multivariada , Cetonas/análiseRESUMO
BACKGROUND: Highland hulless barley has garnered attention as a promising economic product and a potential healthy food ingredient. The present study aimed to comprehensively investigate the molecular structure of extractable fibers obtained from a specific highland hulless barley. Water-soluble fiber (WSF) and alkaline-soluble fiber (ASF) were extracted using enzymatic digestion and an alkaline method, respectively. The purified fibers underwent a thorough investigation for their structural characterization. RESULTS: The monosaccharide composition revealed that WSF primarily consisted of glucose (91.7%), whereas ASF was composed of arabinose (54.5%) and xylose (45.5%), indicating the presence of an arabinoxylan molecule with an A/X ratio of 1.2. The refined structural information was further confirmed through methylation, 1 H NMR and Fourier-transform infrared spectroscopy analyses. WSF fiber exclusively exhibited α-anomeric patterns, suggesting it was an α-glucan. It has a low molecular weight of 5 kDa, as determined by gel permeation chromatography. Conversely, ASF was identified as a heavily branched arabinoxylan with 41.55% of 'â2,3,4)-Xylp-(1â' linkages. ASF and WSF exhibited notable differences in their morphology, water absorption capabilities and rheological properties. CONCLUSION: Based on these findings, molecular models of WSF and ASF were proposed. The deep characterization of these fiber structures provides valuable insights into their physicochemical and functional properties, thereby unlocking their potential applications in the food industry. © 2023 Society of Chemical Industry.
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Hordeum , Hordeum/química , Glucanos/análise , Monossacarídeos , Indústria Alimentícia , Indústria de Processamento de AlimentosRESUMO
Rechargeable Li-Cl2 battery is a promising high energy density battery system. However, reasonable cycle life could only be achieved under low specific capacities due to the sluggish oxidation of LiCl to Cl2 . Herein, we propose an amine-functionalized covalent organic framework (COF) with catalytic activity, namely COF-NH2 , that significantly decreases the oxidation barrier of LiCl and accelerates the oxidation kinetics of LiCl in Li-Cl2 cell. The resulting Li-Cl2 cell using COF-NH2 (Li-Cl2 @COF-NH2 ) simultaneously exhibits low overpotential, ultrahigh discharge capacity up to 3500â mAh/g and a promoted utilization ratio of deposited LiCl at the first cycle (UR-LiCl) of 81.4 %, which is one of the highest reported values to date. Furthermore, the Li-Cl2 @COF-NH2 cell could be stably cycled for over 200â cycles when operating at a capacity of 2000â mAh/g at -20 °C with a Coulombic efficiency (CE) of ≈100 % and a discharge plateau of 3.5â V. Our superior Li-Cl2 batteries enabled by organocatalyst enlighten an arena towards high-energy storage applications.
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The aqueous zinc-iodine battery is a promising energy storage device, but the conventional two-electron reaction potential and energy density of the iodine cathode are far from meeting practical application requirements. Given that iodine is rich in redox reactions, activating the high-valence iodine cathode reaction has become a promising research direction for developing high-voltage zinc-iodine batteries. In this work, by designing a multifunctional electrolyte additive trimethylamine hydrochloride (TAH), a stable high-valence iodine cathode in four-electron-transfer I-/I2/I+ reactions with a high theoretical specific capacity is achieved through a unique amine group, Cl bidentate coordination structure of (TA)ICl. Characterization techniques such as synchrotron radiation, in situ Raman spectra, and DFT calculations are used to verify the mechanism of the stable bidentate structure. This electrolyte additive stabilizes the zinc anode by promoting the desolvation process and shielding mechanism, enabling the zinc anode to cycle steadily at a maximum areal capacity of 57â mAh cm-2 with 97 % zinc utilization rate. Finally, the four-electron-transfer aqueous Zn-I2 full cell achieves 5000 stable cycles at an N/P ratio of 2.5. The unique bidentate coordination structure contributes to the further development of high-valence and high capacity aqueous zinc-iodine batteries.
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Rechargeable Li-Cl2 batteries are recognized as promising candidates for energy storage due to their ultrahigh energy densities and superior safety features. However, Li-Cl2 batteries suffer from a short cycle life and low Coulombic efficiency (CE) at a high specific cycling capacity due to a sluggish and insufficient Cl2 supply during the redox reaction. To achieve Li-Cl2 batteries with high discharge capacity and CE, herein, we propose and design an imine-functionalized porous organic nanocage (POC) to enrich Cl2 molecules. Based on density functional theory (DFT) calculations, the imine group sites in host cages strongly interact with Cl2 molecules, facilitating the rapid capture of Cl2. As a result, the output capacity of the Li-Cl2 battery using POC (Li-Cl2@POC) is significantly boosted, achieving an ultrahigh discharge capacity of 4000 mAh/g at â¼100% CE. Benefiting from the designed POC, the highest utilization ratio of deposited LiCl at the first cycle in the Li-Cl2@POC battery reaches as high as 85%, superior to all reported values. The Li-Cl2@POC battery exhibits excellent electrochemical performance even at low temperatures, delivering stable cycling over 200 cycles under a capacity of 2000 mAh/g at -20 °C with a voltage plateau of 3.5 V and an average CE of 99.7%. We also demonstrate that the Li-Cl2@POC cells can be assembled and well-operated in a dry room, showing advantages for mass production. Our designed POC promotes the practical deployment of rechargeable Li-Cl2 batteries.
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Hydrogen-chlorine (H2-Cl2) fuel cells have distinct merits due to fast electrochemical kinetics but are afflicted by high cost, low efficiency, and poor reversibility. The development of a rechargeable H2-Cl2 battery is highly desirable yet challenging. Here, we report a rechargeable H2-Cl2 battery operating statically in a wide temperature ranging from -70 to 40 °C, which is enabled by a reversible Cl2/Cl- redox cathode and an electrocatalytic H2 anode. A hierarchically porous carbon cathode is designed to achieve effective Cl2 gas confinement and activate the discharge plateau of Cl2/Cl- redox at room temperature, with a discharge plateau at â¼1.15 V and steady cycling for over 500 cycles without capacity decay. Furthermore, the battery operation at an ultralow temperature is successfully achieved in a phosphoric acid-based antifreezing electrolyte, with a reversible discharge capacity of 282 mAh g-1 provided by the highly porous carbon at -70 °C and an average Coulombic efficiency of 91% for more than 300 cycles at -40 °C. This work offers a new strategy to enhance the reversibility of aqueous chlorine batteries for energy storage applications in a wide temperature range.
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BACKGROUND: In clinical practice, some patients with advanced intrahepatic cholangiocarcinoma (ICC) cannot tolerate or refuse chemotherapy due to the toxicity, necessitating alternative treatments. PD-1 blockade combined with lenvatinib showed promising results in phase II studies with small sample size, but there is a lack of data on the routine use with this regimen. This study aimed to evaluate the effectiveness and safety of the regimen in patients with advanced ICC, and to identify predictors for treatment response and prognosis. METHODS: We conducted a retrospective cohort study of patients treated with PD-1 inhibitors plus lenvatinib for advanced ICC between July 2017 and August 2022. The study endpoints were progression-free survival (PFS), overall survival (OS), objective response rate (ORR), disease control rate (DCR), and safety. Biomarker analysis for CA19-9 and PD-L1 expression was performed. Exploratory analysis for genetic alternation was conducted. RESULTS: The study included 103 patients. It demonstrated a median PFS of 5.9 months and a median OS of 11.4 months. ORR was 18.4% and DCR was 80.6%. The incidence of grade 3 or 4 adverse events was 50.5%. Positive PD-L1 expression (TPS ≥ 1%) was associated with higher ORR (P = 0.013) and prolonged PFS (P = 0.023). Elevated CA19-9 (> 37 U/ml) was associated with decreased ORR (P = 0.019), poorer PFS (P = 0.005) and OS (P = 0.034). Patients with IDH1 mutations exhibited a favorable response to the treatment (P = 0.011), and patients with TP53 mutations tended to have worse OS (P = 0.031). CONCLUSIONS: PD-1 blockade plus lenvatinib is effective and safe in routine practice. PD-L1 expression and CA19-9 level appear to predict the treatment efficacy. IDH1 mutations might indicate a better treatment response. CLINICAL TRIAL REGISTRATION: NCT03892577.
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Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Antígeno B7-H1 , Antígeno CA-19-9 , Estudos de Coortes , Receptor de Morte Celular Programada 1 , Estudos Retrospectivos , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/genética , Neoplasias dos Ductos Biliares/tratamento farmacológico , Neoplasias dos Ductos Biliares/genética , Ductos Biliares Intra-HepáticosRESUMO
Selective hydrogenolysis of glycerol to 1,3-propanediol (1,3-PDO) is recognized as one of the most promising reactions for the valorization of biomass. Precise activation of CâO bonds of glycerol molecule is the key step to realize the high yield of catalytic conversion. Here, a Pt-loaded Nb-W composite oxides with crystallographic shear phase for the precise activation and cleavage of secondary CâO (C(2)âO) bonds are first reported. The developed Nb14 W3 O44 with uniform structure possesses arrays of W-O-Nb active sites that totally distinct from individual WOx or NbOx species, which is superior to the adsorption and activation of C(2)âO bonds. The Nb14 W3 O44 support with rich reversible redox couples also promotes the electron feedback ability of Pt and enhances its interaction with Pt nanoparticles, resulting in high activity for H2 dissociation and hydrogenation. All these favorable factors confer the Pt/Nb14 W3 O44 excellent performance for selective hydrogenolysis of glycerol to 1,3-PDO with the yield of 75.2% exceeding the record of 66%, paying the way for the commercial development of biomass conversion. The reported catalysts or approach can also be adopted to create a family of Nb-W metal composite oxides for other catalytic reactions requiring selective CâO bond activation and cleavage.
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Soil biogeochemical processes may present depth-dependent responses to climate change, due to vertical environmental gradients (e.g., thermal and moisture regimes, and the quantity and quality of soil organic matter) along soil profile. However, it is a grand challenge to distinguish such depth dependence under field conditions. Here we present an innovative, cost-effective and simple approach of field incubation of intact soil cores to explore such depth dependence. The approach adopts field incubation of two sets of intact soil cores: one incubated right-side up (i.e., non-inverted), and another upside down (i.e., inverted). This inversion keeps soil intact but changes the depth of the soil layer of same depth origin. Combining reciprocal translocation experiments to generate natural climate shift, we applied this incubation approach along a 2200 m elevational mountainous transect in southeast Tibetan Plateau. We measured soil respiration (Rs) from non-inverted and inverted cores of 1 m deep, respectively, which were exchanged among and incubated at different elevations. The results indicated that Rs responds significantly (p < .05) to translocation-induced climate shifts, but this response is depth-independent. As the incubation proceeds, Rs from both non-inverted and inverted cores become more sensitive to climate shifts, indicating higher vulnerability of persistent soil organic matter (SOM) to climate change than labile components, if labile substrates are assumed to be depleted with the proceeding of incubation. These results show in situ evidence that whole-profile SOM mineralization is sensitive to climate change regardless of the depth location. Together with measurements of vertical physiochemical conditions, the inversion experiment can serve as an experimental platform to elucidate the depth dependence of the response of soil biogeochemical processes to climate change.
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Mudança Climática , Solo , Microbiologia do Solo , Respiração , Carbono , TemperaturaRESUMO
Traffic congestion not only has a great impact on people's travel, but also increases energy consumption and air pollution. The control analysis of the macroscopic traffic flow model considering the vehicle braking effect is particularly important, reflecting the impact on the actual traffic flow density wave, so as to better solve the actual traffic problems. In this paper, based on a speed difference optimization speed model, the micro-macro-variables are transformed into a high-order continuous traffic flow model. Then, a random function considering the physical correlation of random components is added to the high-order continuous traffic flow model to establish a random traffic flow model that can reflect the uncertain behavior of traffic flow acceleration or deceleration. Based on this stochastic traffic model, the existence of Hopf bifurcation and bifurcation control of the traffic flow system model considering stochastic characteristics are derived by using Hopf bifurcation theorem. By Chebyshev polynomial approximation method, the stochastic problem of the system is transformed into the bifurcation control problem of its equivalent deterministic system. A feedback controller is designed to delay the occurrence of Hopf bifurcation and control the amplitude of the limit cycle. Without changing the equilibrium point of the system, the complete elimination of Hopf bifurcation can be achieved by controlling the amplitude of the limit cycle. That is, the feedback controller is used to modify the bifurcation characteristics of the system, such as the bifurcation appearing at the equilibrium point in the control system moves forward, moves backward or disappears, so as to achieve the effect of preventing or alleviating traffic congestion.
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Bisphenol A (BPA), one of the widely known endocrine-disrupting chemicals, can be effectively degraded by advanced oxidation processes in water because of the powerful reactive oxygen species. In this study, Fenton, UV/Fenton, and metal ion/peroxymonosulfate (PMS) processes were compared to investigate BPA degradation efficiency and pathways initiated by hydroxyl radicals and sulfate radicals. In contrast to the Fenton system, which only degraded 60% of BPA within 15 min, the UV/Fenton system could degrade greater than 80% of BPA, because more hydroxyl radicals (â¢OH) were generated under the reduction of Fe3+ to Fe2+. The optimized parameters of the UV/Fenton system were as follows: 8 µmol/L of Fe2+, 80 µmol/L of H2O2, and a pH value of 3.0. As for the metal ion/PMS system, the BPA degradation efficiency was closely associated with the applied metal ions, and the order was as follows: Co2+/PMS (â¼100%) > Fe2+/PMS (â¼80%) > Cu2+/PMS (â¼79%). The degradation pathways of BPA were theoretically interpreted through density functional theory prediction and degradation products during various processes. Two major initial reaction sites (4C and 6C) for â¢OH initiated using the UV/Fenton system and one initial reaction site (4C) for sulfate radicals (SO4â¢-) using the metal ion/PMS system were recognized for BPA degradation processes. The degradation products by â¢OH showed a larger average molecular weight than those by SO4â¢-. These studies are instructive for the application of different advanced oxidation systems in the treatment process of BPA in wastewater.