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1.
Genes Dev ; 35(3-4): 218-233, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33446568

RESUMO

Pancreatic ductal adenocarcinoma is a lethal disease characterized by late diagnosis, propensity for early metastasis and resistance to chemotherapy. Little is known about the mechanisms that drive innate therapeutic resistance in pancreatic cancer. The ataxia-telangiectasia group D-associated gene (ATDC) is overexpressed in pancreatic cancer and promotes tumor growth and metastasis. Our study reveals that increased ATDC levels protect cancer cells from reactive oxygen species (ROS) via stabilization of nuclear factor erythroid 2-related factor 2 (NRF2). Mechanistically, ATDC binds to Kelch-like ECH-associated protein 1 (KEAP1), the principal regulator of NRF2 degradation, and thereby prevents degradation of NRF2 resulting in activation of a NRF2-dependent transcriptional program, reduced intracellular ROS and enhanced chemoresistance. Our findings define a novel role of ATDC in regulating redox balance and chemotherapeutic resistance by modulating NRF2 activity.


Assuntos
Carcinogênese/genética , Proteínas de Ligação a DNA/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Neoplasias Pancreáticas/fisiopatologia , Fatores de Transcrição/metabolismo , Humanos , Ligação Proteica , Neoplasias Pancreáticas
2.
Genes Dev ; 33(11-12): 641-655, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31048544

RESUMO

Pancreatic adenocarcinoma (PDA) is an aggressive disease driven by oncogenic KRAS and characterized by late diagnosis and therapeutic resistance. Here we show that deletion of the ataxia-telangiectasia group D-complementing (Atdc) gene, whose human homolog is up-regulated in the majority of pancreatic adenocarcinoma, completely prevents PDA development in the context of oncogenic KRAS. ATDC is required for KRAS-driven acinar-ductal metaplasia (ADM) and its progression to pancreatic intraepithelial neoplasia (PanIN). As a result, mice lacking ATDC are protected from developing PDA. Mechanistically, we show ATDC promotes ADM progression to PanIN through activation of ß-catenin signaling and subsequent SOX9 up-regulation. These results provide new insight into PDA initiation and reveal ATDC as a potential target for preventing early tumor-initiating events.


Assuntos
Carcinogênese , Carcinoma Ductal Pancreático/fisiopatologia , Neoplasias Pancreáticas/fisiopatologia , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Fatores de Transcrição/fisiologia , Células Acinares/metabolismo , Células Acinares/patologia , Animais , Carcinoma in Situ/patologia , Carcinoma in Situ/fisiopatologia , Carcinoma Ductal Pancreático/patologia , Transdiferenciação Celular , Células Cultivadas , Proteínas de Ligação a DNA/metabolismo , Regulação para Baixo , Técnicas de Silenciamento de Genes , Humanos , Metaplasia , Camundongos , Camundongos Transgênicos , Ductos Pancreáticos/metabolismo , Ductos Pancreáticos/patologia , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , beta Catenina/metabolismo
3.
Proc Natl Acad Sci U S A ; 119(1)2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34930823

RESUMO

Coxiella burnetii is a bacterial pathogen that replicates within host cells by establishing a membrane-bound niche called the Coxiella-containing vacuole. Biogenesis of this compartment requires effectors of its Dot/Icm type IV secretion system. A large cohort of such effectors has been identified, but the function of most of them remain elusive. Here, by a cell-based functional screening, we identified the effector Cbu0513 (designated as CinF) as an inhibitor of NF-κB signaling. CinF is highly similar to a fructose-1,6-bisphosphate (FBP) aldolase/phosphatase present in diverse bacteria. Further study reveals that unlike its ortholog from Sulfolobus tokodaii, CinF does not exhibit FBP phosphatase activity. Instead, it functions as a protein phosphatase that specifically dephosphorylates and stabilizes IκBα. The IκBα phosphatase activity is essential for the role of CinF in C. burnetii virulence. Our results establish that C. burnetii utilizes a protein adapted from sugar metabolism to subvert host immunity.


Assuntos
Proteínas de Bactérias , Coxiella burnetii , Fosfoproteínas Fosfatases , Febre Q , Transdução de Sinais , Fatores de Virulência , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Chlorocebus aethiops , Coxiella burnetii/genética , Coxiella burnetii/imunologia , Coxiella burnetii/patogenicidade , Células HEK293 , Células HeLa , Humanos , NF-kappa B/genética , NF-kappa B/imunologia , Fosfoproteínas Fosfatases/genética , Fosfoproteínas Fosfatases/imunologia , Febre Q/genética , Febre Q/imunologia , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Células Vero , Fatores de Virulência/genética , Fatores de Virulência/imunologia
4.
Mol Med ; 30(1): 46, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38584262

RESUMO

Effective therapeutic targets and early diagnosis are major challenges in the treatment of gastrointestinal tract (GIT) cancers. SALL4 is a well-known transcription factor that is involved in organogenesis during embryonic development. Previous studies have revealed that SALL4 regulates cell proliferation, survival, and migration and maintains stem cell function in mature cells. Additionally, SALL4 overexpression is associated with tumorigenesis. Despite its characterization as a biomarker in various cancers, the role of SALL4 in GIT cancers and the underlying mechanisms are unclear. We describe the functions of SALL4 in GIT cancers and discuss its upstream/downstream genes and pathways associated with each cancer. We also consider the possibility of targeting these genes or pathways as potential therapeutic options for GIT cancers.


Assuntos
Neoplasias Gastrointestinais , Fatores de Transcrição , Humanos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Neoplasias Gastrointestinais/genética , Células-Tronco/metabolismo , Desenvolvimento Embrionário , Linhagem Celular Tumoral
5.
BMC Plant Biol ; 24(1): 432, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773389

RESUMO

The VIM (belonged to E3 ubiquitin ligase) gene family is crucial for plant growth, development, and stress responses, yet their role in salt stress remains unclear. We analyzed phylogenetic relationships, chromosomal localization, conserved motifs, gene structure, cis-acting elements, and gene expression patterns of the VIM gene family in four cotton varieties. Our findings reveal 29, 29, 17, and 14 members in Gossypium hirsutum (G.hirsutum), Gossypium barbadense (G.barbadense), Gossypium arboreum (G.arboreum), and Gossypium raimondii (G. raimondii), respectively, indicating the maturity and evolution of this gene family. motifs among GhVIMs genes were observed, along with the presence of stress-responsive, hormone-responsive, and growth-related elements in their promoter regions. Gene expression analysis showed varying patterns and tissue specificity of GhVIMs genes under abiotic stress. Silencing GhVIM28 via virus-induced gene silencing revealed its role as a salt-tolerant negative regulator. This work reveals a mechanism by which the VIM gene family in response to salt stress in cotton, identifying a potential negative regulator, GhVIM28, which could be targeted for enhancing salt tolerance in cotton. The objective of this study was to explore the evolutionary relationship of the VIM gene family and its potential function in salt stress tolerance, and provide important genetic resources for salt tolerance breeding of cotton.


Assuntos
Regulação da Expressão Gênica de Plantas , Gossypium , Família Multigênica , Filogenia , Proteínas de Plantas , Estresse Salino , Gossypium/genética , Gossypium/fisiologia , Estresse Salino/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Genes de Plantas , Tolerância ao Sal/genética
6.
Small ; : e2400661, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38597688

RESUMO

Renewable energy-driven conversion of CO2 to value-added fuels and chemicals via electrochemical CO2 reduction reaction (CO2RR) technology is regarded as a promising strategy with substantial environmental and economic benefits to achieve carbon neutrality. Because of its sluggish kinetics and complex reaction paths, developing robust catalytic materials with exceptional selectivity to the targeted products is one of the core issues, especially for extensively concerned Cu-based materials. Manipulating Cu species by anionic coordination is identified as an effective way to improve electrocatalytic performance, in terms of modulating active sites and regulating structural reconstruction. This review elaborates on recent discoveries and progress of Cu-based CO2RR catalytic materials enhanced by anionic coordination control, regarding reaction paths, functional mechanisms, and roles of different non-metallic anions in catalysis. Finally, the review concludes with some personal insights and provides challenges and perspectives on the utilization of this strategy to build desirable electrocatalysts.

7.
Environ Sci Technol ; 58(16): 6978-6987, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38598712

RESUMO

Decarbonization of the cement sector is essentially required to achieve carbon neutrality to combat climate change. Amine-based CO2 capture is a leading and practical technology to deeply remove CO2 from the cement industry, owing to its high retrofittability to existing cement plants and extensive engineering experience in industrial flue gas decarbonization. While research efforts have been made to achieve low-carbon cement with 90% CO2 removal, a net-zero-emission cement plant that will be required for a carbon neutrality society has not yet been investigated. The present study proposed an advanced amine-based CO2 capture system integrated with a cement plant to achieve net-zero CO2 emission by pushing the CO2 capture efficiency to 99.7%. Monoethanomaine (MEA) and piperazine/2-amino-2-methyl-1-propanol (PZ-AMP) amine systems, which are considered to be the first- and second-generation capture agents, respectively, were detailed investigated to deeply decarbonize the cement plant. Compared to MEA, the advanced PZ-AMP system exhibited excellent energy performance with a regeneration duty of ∼2.6 GJ/tonne CO2 at 99.7% capture, 39% lower than the MEA process. This enabled a low CO2 avoided cost of $72.0/tonne CO2, which was 18% lower than that of the MEA-based zero-emission process and even 16.2% lower than the standard 90% MEA process. Sensitivity analysis revealed that the zero-emission capture cost of the PZ-AMP system would be further reduced to below $56/tonne CO2 at a $4/GJ steam production cost, indicating its economic competitiveness among various CO2 capture technologies to achieve a zero-emission cement plant.


Assuntos
Aminas , Dióxido de Carbono , Dióxido de Carbono/química , Aminas/química , Materiais de Construção
8.
Environ Sci Technol ; 58(10): 4606-4616, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38427797

RESUMO

Transforming hazardous species into active sites by ingenious material design was a promising and positive strategy to improve catalytic reactions in industrial applications. To synergistically address the issue of sluggish CO2 desorption kinetics and SO2-poisoning solvent of amine scrubbing, we propose a novel method for preparing a high-performance core-shell C@Mn3O4 catalyst for heterogeneous sulfur migration and in situ reconstruction to active -SO3H groups, and thus inducing an enhanced proton-coupled electron transfer (PCET) effect for CO2 desorption. As anticipated, the rate of CO2 desorption increases significantly, by 255%, when SO2 is introduced. On a bench scale, dynamic CO2 capture experiments reveal that the catalytic regeneration heat duty of SO2-poisoned solvent experiences a 32% reduction compared to the blank case, while the durability of the catalyst is confirmed. Thus, the enhanced PCET of C@Mn3O4, facilitated by sulfur migration and simultaneous transformation, effectively improves the SO2 resistance and regeneration efficiency of amine solvents, providing a novel route for pursuing cost-effective CO2 capture with an amine solvent.


Assuntos
Dióxido de Carbono , Prótons , Elétrons , Solventes , Aminas , Enxofre
9.
Environ Sci Technol ; 58(12): 5557-5566, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38412381

RESUMO

Wet flue gas denitrification offers a new route to convert industrial nitrogen oxides (NOx) into highly concentrated nitrate wastewater, from which the nitrogen resource can be recovered to ammonia (NH3) via electrochemical nitrate reduction reactions (NITRRs). Low-cost, scalable, and efficient cathodic materials need to be developed to enhance the NH3 production rate. Here, in situ electrodeposition was adopted to fabricate a foamy Cu-based heterojunction electrode containing both Cu-defects and oxygen vacancy loaded Cu2O (OVs-Cu2O), which achieved an NH3 yield rate of 3.59 mmol h-1 cm-2, NH3 Faradaic efficiency of 99.5%, and NH3 selectivity of 100%. Characterizations and theoretical calculations unveiled that the Cu-defects and OVs-Cu2O heterojunction boosted the H* yield, suppressed the hydrogen evolution reaction (HER), and served as dual reaction sites to coherently match the tandem reactions kinetics of NO3-to-NO2 and NO2-to-NH3. An integrated system was further built to combine wet flue gas denitrification and desulfurization, simultaneously converting NO and SO2 to produce the (NH4)2SO4 fertilizer. This study offers new insights into the application of low-cost Cu-based cathode for electrochemically driven wet denitrification wastewater valorization.


Assuntos
Amônia , Águas Residuárias , Nitratos/química , Dióxido de Nitrogênio , Desnitrificação , Eletrodos
10.
Chem Soc Rev ; 52(17): 5827-5860, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37531220

RESUMO

The shortage of freshwater resources caused by heavy metal pollution is an acute global issue, which has a great impact on environmental protection and human health. Therefore, the exploitation of new strategies for designing and synthesizing green, efficient, and economical materials for the detection and removal of heavy metal ions is crucial. Among the various methods for the detection and removal of heavy ions, advanced functional systems including nanomaterials, polymers, porous materials, and biomaterials have attracted considerable attention over the past several years due to their capabilities of real-time detection, excellent removal efficiency, anti-interference, quick response, high selectivity, and low limit of detection. In this tutorial review, we review the general design principles underlying the aforementioned functional materials, and in particular highlight the fundamental mechanisms and specific examples of detecting and removing heavy metal ions. Additionally, the methods which enhance water purification quality using these functional materials have been reviewed, also current challenges and opportunities in this exciting field have been highlighted, including the fabrication, subsequent treatment, and potential future applications of such functional materials. We envision that this tutorial review will provide invaluable guidance for the design of functional materials tailored towards the detection and removal of heavy metals, thereby expediting the development of high-performance materials and fostering the development of more efficient approaches to water pollution remediation.

11.
Entropy (Basel) ; 26(1)2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38248173

RESUMO

This paper introduces the notion of multi-sensitivity with respect to a vector within the context of non-autonomous dynamical systems on uniform spaces and provides insightful results regarding N-sensitivity and strongly multi-sensitivity, along with their behaviors under various conditions. The main results established are as follows: (1) For a k-periodic nonautonomous dynamical system on a Hausdorff uniform space (S,U), the system (S,fk∘⋯∘f1) exhibits N-sensitivity (or strongly multi-sensitivity) if and only if the system (S,f1,∞) displays N-sensitivity (or strongly multi-sensitivity). (2) Consider a finitely generated family of surjective maps on uniform space (S,U). If the system (S,f1,∞) is N-sensitive, then the system (S,fk,∞) is also N-sensitive. When the family f1,∞ is feebly open, the converse statement holds true as well. (3) Within a finitely generated family on uniform space (S,U), N-sensitivity (and strongly multi-sensitivity) persists under iteration. (4) We present a sufficient condition under which an nonautonomous dynamical system on infinite Hausdorff uniform space demonstrates N-sensitivity.

12.
Entropy (Basel) ; 26(6)2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38920457

RESUMO

In the realm of cardiac research, the control of spiral waves and turbulent states has been a persistent focus for scholars. Among various avenues of investigation, the modulation of ion currents represents a crucial direction. It has been proved that the methods involving combined control of currents are superior to singular approaches. While previous studies have proposed some combination strategies, further reinforcement and supplementation are required, particularly in the context of controlling arrhythmias through the combined regulation of two potassium ion currents. This study employs the Luo-Rudy phase I cardiac model, modulating the maximum conductance of the time-dependent potassium current and the time-independent potassium current, to investigate the effects of this combined modulation on spiral waves and turbulent states. Numerical simulation results indicate that, compared to modulating a single current, combining reductions in the conductance of two potassium ion currents can rapidly control spiral waves and turbulent states in a short duration. This implies that employing blockers for both potassium ion currents concurrently represents a more efficient control strategy. The control outcomes of this study represent a novel and effective combination for antiarrhythmic interventions, offering potential avenues for new antiarrhythmic drug targets.

13.
BMC Genomics ; 24(1): 507, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37648967

RESUMO

BACKGROUND: The Mongolian gazelle (Procapra gutturosa) population has shown a considerable range of contractions and local extinctions over the last century, owing to habitat fragmentation and poaching. A thorough understanding of the genetic diversity and structure of Mongolian gazelle populations in fragmented habitats is critical for planning effective conservation strategies. RESULT: In this study, we used eight microsatellite loci and mitochondrial cytochrome b (Cytb) to compare the levels of genetic diversity and genetic structure of Mongolian gazelle populations in the Hulun Lake National Nature Reserve (HLH) with those in the China-Mongolia border area (BJ). The results showed that the nucleotide diversity and observed heterozygosity of the HLH population were lower than those of the BJ population. Moreover, the HLH and BJ populations showed genetic differentiation. We concluded that the HLH population had lower genetic diversity and a distinct genetic structure compared with the BJ population. CONCLUSION: The genetic diversity of fragmented Mongolian gazelle populations, can be improved by protecting these populations while reinforcing their gene exchange with other populations. For example, attempts can be made to introduce new individuals with higher genetic diversity from other populations to reduce inbreeding.


Assuntos
Antílopes , Humanos , Animais , Antílopes/genética , China , Citocromos b/genética , Deriva Genética , Variação Genética
14.
J Am Chem Soc ; 145(36): 20000-20008, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37610355

RESUMO

Advances in single-atom (-site) catalysts (SACs) provide a new solution of atomic economy and accuracy for designing efficient electrocatalysts. In addition to a precise local coordination environment, controllable spatial active structure and tolerance under harsh operating conditions remain great challenges in the development of SACs. Here, we show a series of molecule-spaced SACs (msSACs) using different acid anhydrides to regulate the spatial density of discrete metal phthalocyanines with single Co sites, which significantly improve the effective active-site numbers and mass transfer, enabling one of the msSACs connected by pyromellitic dianhydride to exhibit an outstanding mass activity of (1.63 ± 0.01) × 105 A·g-1 and TOFbulk of 27.66 ± 1.59 s-1 at 1.58 V (vs RHE) and long-term durability at an ultrahigh current density of 2.0 A·cm-2 under industrial conditions for oxygen evolution reaction. This study demonstrates that the accessible spatial density of single atom sites can be another important parameter to enhance the overall performance of catalysts.

15.
Funct Integr Genomics ; 23(1): 28, 2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36598654

RESUMO

Increasing evidence has demonstrated that lncRNA plays a significant role in the immunity regulation of gastric adenocarcinoma. However, the immune-related lncRNAs and the prognostic value in immunotherapies remain largely unexplored. We collected immune-related lncRNA and the associated pathways of gastric cancer from the ImmLnc database. The cox regression model is used to analyze the prognostic value of these lncRNAs. Gastric cancer is further divided into different subtypes based on these lncRNAs. Tumor microenvironment analysis, functional enrichment analysis, and genomic alteration analysis are performed for different subtypes. Furthermore, chemotherapeutic and immunotherapeutic sensitivity are also analyzed among different subtypes. Nine lncRNAs are identified as significant regulators of the immune pathway of gastric cancer. Gastric cancer can be classified into 5 subtypes based on these lncRNAs. Tumor microenvironment analysis shows that cluster C3 has the highest immune score and C5 has the lowest score. Functional analysis shows that these subtypes are enriched with distinct biological processes. Genomic analysis shows that LAMA2 mutation is a protective factor in C3 but a risk factor in C5. Furthermore, these subtypes are found to respond distinctly to the same chemotherapeutic and immunotherapeutic drugs. In this study, we analyzed the immune-related lncRNA and identified the crucial role in the regulation of immune properties, biological processes, and immunotherapeutic sensitivity. These findings can improve our understanding of the epigenetic immunoregulation of lncRNA and advance the research of immunotherapy.


Assuntos
Adenocarcinoma , RNA Longo não Codificante , Neoplasias Gástricas , Humanos , Relevância Clínica , RNA Longo não Codificante/genética , Neoplasias Gástricas/genética , Adenocarcinoma/genética , Epigenômica , Microambiente Tumoral/genética
16.
Cancer Cell Int ; 23(1): 191, 2023 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-37660003

RESUMO

BACKGROUND: Progranulin (PGRN), a glycoprotein secreted by a wide range of epithelial cells and plays an important role in inflammatory mechanisms and tumor progression. In this study, the expression, and functions of PGRN in papillary thyroid carcinoma (PTC) was examined to explore the potential pathogenesis of PTC. METHODS: Western blotting and qRT-PCR were used to detect the relationship between PGRN expression and clinicopathological characteristics of patients with PTC. PTC cell lines with PGRN overexpression and with PGRN knockdown were established to explore their effects on the biological behavior. Western blotting was used to detect the changes of relevant molecules and JAK2-STAT3/4 signaling pathway. Moreover, rescue experiments validated the involvement of the JAK2-STAT3/4 signaling pathway. And statistical analyses were analyzed using SPASS 21.0 and graph generation were performed using GraphPad Prism 8.0. RESULTS: PGRN was overexpressed in PTC tissue and increased by 75% at mRNA level and 161% at relative protein level in the patients with lymph node metastasis compared to without lymph node metastasis. Besides, PGRN regulated and promoted PTC cell proliferation, migration, invasion, and inhibited cell apoptosis. With PGRN overexpressed, relevant molecules including the expression of BCL2/BAX, BCL2/BAD, CyclinD1, MMP2, vimentin and N-cadherin were increased, the expression level of E-cadherin was decreased, and the phosphorylation of JAK2 and STAT3/4 were increased. JAK inhibitor (JSI-124) rescued these changes of PTC cells induced by overexpressed PGRN. CONCLUSIONS: These findings revealed that PGRN promote the progression of PTC through the JAK2-STAT3/4 pathway, and PGRN could be served as a potential therapeutic target for PTC.

17.
Theor Appl Genet ; 136(3): 45, 2023 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-36905488

RESUMO

KEY MESSAGE: Leaf senescence in sorghum is primarily controlled by the progression, but not by the onset of senescence. The senescence-delaying haplotypes of 45 key genes accentuated from landraces to improved lines. Leaf senescence is a genetically programmed developmental process and plays a central role for plant survival and crop production by remobilising nutrients accumulated in senescent leaves. In theory, the ultimate outcome of leaf senescence is determined by the onset and progression of senescence, but how these two processes contribute to senescence is not fully illustrated in crops and the genetic basis for them is not well understood. Sorghum (Sorghum bicolor), which is known for the remarkable stay-green trait, is ideal for dissecting the genomic architecture underlying the regulation of senescence. In this study, a diverse panel of 333 sorghum lines was explored for the onset and progression of leaf senescence. Trait correlation analysis showed that the progression of leaf senescence, rather than the onset of leaf senescence, significantly correlated with variations of the final leaf greenness. This notion was further supported by GWAS, which identified 31 senescence-associated genomic regions containing 148 genes, of which 124 were related to the progression of leaf senescence. The senescence-delaying haplotypes of 45 key candidate genes were enriched in lines with extremely prolonged senescence duration, while senescence-promoting haplotypes in those with extremely accelerated senescence. Haplotype combinations of these genes could well explain the segregation of the senescence trait in a recombinant inbred population. We also demonstrated that senescence-delaying haplotypes of candidate genes were under strong selection during sorghum domestication and genetic improvement. Together, this research advanced our understanding of crop leaf senescence and provided a suite of candidate genes for functional genomics and molecular breeding.


Assuntos
Sorghum , Sorghum/genética , Senescência Vegetal , Locos de Características Quantitativas , Fenótipo , Grão Comestível/genética , Genômica
18.
Inorg Chem ; 62(7): 3297-3304, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36758163

RESUMO

Remodeling the active surface through fabricating heterostructures can substantially enhance alkaline water electrolysis driven by renewable electrical energy. However, there are still great challenges in the synthesis of highly reactive and robust heterostructures to achieve both ampere-level current density hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Herein, we report a new Co/CeO2 heterojunction self-supported electrode for sustainable overall water splitting. The self-supporting Co/CeO2 heterostructures required only low overpotentials of 31.9 ± 2.2, 253.3 ± 2.7, and 316.7 ± 3 mV for HER and 214.1 ± 1.4, 362.3 ± 1.9, and 400.3 ± 3.7 mV for OER at 0.01, 0.5, and 1.0 A·cm-2, respectively, being one of the best Co-based bifunctional electrodes. Electrolyzer constructed from this electrode acting as an anode and cathode merely required cell voltages of 1.92 ± 0.02 V at 1.0 A·cm-2 for overall water splitting. Multiple characterization techniques combined with density functional theory calculations disclosed the different active sites on the anode and cathode, and the charge redistributions on the heterointerfaces that can optimize the adsorption of H and oxygen-containing intermediates, respectively. This study presents the tremendous prospective of self-supporting heterostructures for effective and economical overall water splitting.

19.
Environ Sci Technol ; 57(41): 15465-15474, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37782821

RESUMO

Metal-molecular sieve composites with high acidity are promising solid acid catalysts (SACs) for accelerating sluggish CO2 desorption processes and reducing the energy consumption of CO2 chemisorption systems. However, the production of such SACs through conventional approaches such as loading or ion-exchange methods often leads to uncontrolled and unstable metal distribution on the catalysts, which limits their pore structure regulation and catalytic performance. In this study, we demonstrated a feasible strategy for improving the durability, surface chemical activity, and pore structure of metal-doped HZSM-5 through bimetallic Mo/Mn modification. This strategy involves the immobilization of Mo-O-Mn species confined in an MFI structure by regulating MoO42- anions and Mn2+ cations. The embedded Mn/Mo species of low valence can strongly induce electron transfer and increase the density of compensatory H+ on the MoMn@H catalyst, thereby reducing the CO2 desorption temperature by 8.27 °C and energy consumption by 37% in comparison to a blank. The durability enhancement and activity regulation method used in this study is expected to advance the rational synthesis of metal-molecular sieve composites for energy-efficient CO2 capture using amine regeneration technology.


Assuntos
Aminas , Dióxido de Carbono , Catálise , Transporte de Elétrons , Troca Iônica
20.
Environ Sci Technol ; 57(45): 17553-17565, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37917662

RESUMO

The hydrogenation of organic sulfur (CS2) present in industrial off-gases to produce sulfur-free hydrocarbons and H2S can be achieved by using noble-metal catalysts. However, there has been a lack of comprehensive investigation into the underlying reaction mechanisms associated with this process. In this study, we have conducted an in-depth examination of the activity and selectivity of Pt- and Pd-loaded alumina-based catalysts, revealing significant disparities between them. Notably, Pd/Al2O3 catalysts exhibit an enhanced performance at low temperatures. Furthermore, we have observed that CS2 displays a higher propensity for conversion to methane when employing Pt/Al2O3 catalysts, while Pd/Al2O3 catalysts demonstrate a greater tendency for coke deposition. By combining experimental observations with theoretical calculations, we revealed that the capability of H2 spillover along with the adsorption capacity of CS2, play pivotal roles in determining the observed differences. Moreover, the key intermediate species involved in the methanation and coke pathways were identified. The intermediate CH2S* is found to be crucial in the methanation pathway, while the intermediate CSH* is identified as significant in the coke pathway.


Assuntos
Coque , Adsorção , Óxido de Alumínio , Hidrogenação , Enxofre
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