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Background: Type 2 Diabetes Mellitus (T2D) and Osteoarthritis (OA) are both prevalent diseases that significantly impact the health of patients. Increasing evidence suggests that there is a big correlation between T2D and OA, but the molecular mechanisms remain elusive. The aims of this study are to investigate the shared biomarkers and potential molecular mechanisms in T2D combined with OA. Methods: T2D and OA-related differentially expressed genes (DEGs) were identified via bioinformatic analysis on Gene Expression Omnibus (GEO) datasets GSE26168 and GSE114007 respectively. Subsequently, extensive target prediction and network analysis were finished with Gene Ontology (GO), protein-protein interaction (PPI), and pathway enrichment with DEGs. The transcription factors (TFs) and miRNAs coupled in co-expressed DEGs involved in T2D and OA were predicted as well. The key genes expressed both in the clinical tissues of T2D and OA were detected with western blot and qRT-PCR assay. Finally, the most promising candidate compounds were predicted with the Drug-Gene Interaction Database (DGIdb) and molecular docking. Results: In this study, 209 shared DEGs between T2D and OA were identified. Functional analysis disclosed that these DEGs are predominantly related to ossification, regulation of leukocyte migration, extracellular matrix (ECM) structural constituents, PI3K/AKT, and Wnt signaling pathways. Further analysis via Protein-Protein Interaction (PPI) analysis and validation with external datasets emphasized MMP9 and ANGPTL4 as crucial genes in both T2D and OA. Our findings were validated through qRT-PCR and Western blot analyses, which indicated high expression levels of these pivotal genes in T2D, OA, and T2D combined with OA cases. Additionally, the analysis of Transcription Factors (TFs)-miRNA interactions identified 7 TFs and one miRNA that jointly regulate these important genes. The Receiver Operating characteristic (ROC) analysis demonstrated the significant diagnostic potential of MMP9 and ANGPTL4.Moreover, we identified raloxifene, ezetimibe, and S-3304 as promising agents for patients with both T2D and OA. Conclusion: This study uncovers the shared signaling pathways, biomarkers, potential therapeutics, and diagnostic models for individuals suffering from both T2D and OA. These findings not only present novel perspectives on the complex interplay between T2D and OA but also hold significant promise for improving the clinical management and prognosis of patients with this concurrent condition.
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Biologia Computacional , Diabetes Mellitus Tipo 2 , Redes Reguladoras de Genes , Osteoartrite , Mapas de Interação de Proteínas , Humanos , Diabetes Mellitus Tipo 2/genética , Osteoartrite/genética , Osteoartrite/metabolismo , Biologia Computacional/métodos , Perfilação da Expressão Gênica , MicroRNAs/genética , Regulação da Expressão Gênica , Bases de Dados Genéticas , Proteína 4 Semelhante a Angiopoietina/genética , Proteína 4 Semelhante a Angiopoietina/metabolismo , Simulação de Acoplamento Molecular , Biomarcadores , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
SAPO-37 molecular sieve, characterized by its three-dimensional 12-membered-ring FAU structure, has drawn wide attention due to its unique properties and catalytic potential. However, its susceptibility to framework collapse under low-temperature and humid conditions hinders practical applications, affecting both the reaction performance and sample storage. To tackle this, we utilized aluminum phosphate as a precursor for synthesizing SAPO-37, aiming to modify Si incorporation mechanisms and improve P and Al environments. Solid NMR spectroscopy combined with other techniques proves that the resulting SAPO-37-AP has enriched silicon islands, leading to reduced water adsorption, more reversible structural change, and significantly enhanced stability after low-temperature vapor treatment compared to conventional SAPO-37. Remarkably, SAPO-37-AP, after water vapor treatment, still exhibits superior performance in the liquid-phase Beckmann rearrangement reaction. This approach enhances stability, reduces templating agent amounts, and improves the solid product yield, offering promising practical applications.
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Transcription factors play crucial roles in almost all physiological processes including leaf senescence. Cell death is a typical symptom appearing in senescing leaves, which is also classified as developmental programmed cell death (PCD). However, the link between PCD and leaf senescence still remains unclear. Here, we found a WRKY transcription factor WRKY47 positively modulates age-dependent leaf senescence in Arabidopsis (Arabidopsis thaliana). WRKY47 was expressed preferentially in senescing leaves. A subcellular localization assay indicated that WRKY47 was exclusively localized in nuclei. Overexpression of WRKY47 showed precocious leaf senescence, with less chlorophyll content and higher electrolyte leakage, but loss-of-function mutants of WRKY47 delayed this biological process. Through qRT-PCR and dual luciferase reporter assays, we found that WRKY47 could activate the expression of senescence-associated genes (SAGs) and PCD-associated genes to regulate leaf senescence. Furthermore, through electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP)-qPCR, WRKY47 was found to bind to W-box fragments in promoter regions of BFN1 (Bifunctional Nuclease 1) and MC6 (Metacaspase 6) directly. In general, our research revealed that WRKY47 regulates age-dependent leaf senescence by activating the transcription of two PCD-associated genes.
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Proteínas de Arabidopsis , Arabidopsis , Regulação da Expressão Gênica de Plantas , Folhas de Planta , Senescência Vegetal , Fatores de Transcrição , Apoptose/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/genética , Senescência Vegetal/genética , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genéticaRESUMO
Interfacial hydrogen transfer between metal particles and catalyst supports is a ubiquitous phenomenon in heterogeneous catalysis, and this occurrence on reducible supports has been established, yet controversies remain about how hydrogen transfer can take place on nonreducible supports, such as silica. Herein, highly dispersed Pt clusters supported on a series of porous silica materials with zeolitic or/and amorphous frameworks were prepared to interrogate the nature of hydrogen transfer and its promotional effect on H2-HDO isotope catalytic exchange. The formation of zeolitic frameworks upon these porous silica supports by hydrothermal crystallization greatly promotes the interfacial hydrogen bidirectional migration between metal clusters and supports. Benefiting from this transfer effect, the isotope exchange rate is enhanced by 10 times compared to that on the amorphous counterpart (e.g., Pt/SBA-15). In situ spectroscopic and theoretical studies suggest that the defective silanols formed within the zeolite framework serve as the reactive sites to bind HDO or H2O by hydrogen bonds. Under the electrostatic attraction interaction, the D of hydrogen-bonded HDO scrambles to the Pt site and the dissociated H on Pt simultaneously spills back to the electronegative oxygen atom of adsorbed water to attain H-D isotope exchange with an energy barrier of 0.43 eV. The reverse spillover D on Pt combines with the other H on Pt to form HD in the effluent. We anticipate that these findings are able to improve our understanding of hydrogen transfer between metal and silica supports and favor the catalyst design for the hydrogen-involving reaction.
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A rapid and eco-friendly route has been developed for the synthesis of SAPO-34 with short crystallization time (1-3 h), low silica content (as low as 6.2 wt%) and excellent methanol-to-olefin (MTO) catalytic performance by utilization of a recycled mother liquid at elevated crystallization temperature.
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The inherent inertness and striking physicochemical similarities of krypton and xenon pose significant challenges to their separation. Reported herein is the efficient xenon capture and xenon/krypton adsorptive separation by transition metal-free zeolites under ambient conditions. The polarized environment of zeolite, denoted as local polarity, can be tuned by changing the topology, framework composition, and counter-cations, which in turn correlates with the guest-host interaction and separation performance. Chabazite zeolite with a framework Si/Al ratio of 2.5 and Ca2+ as the counter-cations, namely, Ca-CHA-2.5, is developed as a state-of-the-art zeolite adsorbent, showing remarkable performance, i.e., high dynamic xenon uptake, high xenon/krypton separation selectivity, and good recyclability, in the adsorptive separation of the xenon/krypton mixture. Grand Canonical Monte Carlo simulation reveals that extraframework Ca2+ cations act as the primary binding sites for xenon and can stabilize xenon molecules together with the chabazite framework, whereas krypton molecules are stabilized by weak guest-host interaction with the zeolite framework.
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Stable aluminosilicate zeolites with extra-large pores that are open through rings of more than 12 tetrahedra could be used to process molecules larger than those currently manageable in zeolite materials. However, until very recently1-3, they proved elusive. In analogy to the interlayer expansion of layered zeolite precursors4,5, we report a strategy that yields thermally and hydrothermally stable silicates by expansion of a one-dimensional silicate chain with an intercalated silylating agent that separates and connects the chains. As a result, zeolites with extra-large pores delimited by 20, 16 and 16 Si tetrahedra along the three crystallographic directions are obtained. The as-made interchain-expanded zeolite contains dangling Si-CH3 groups that, by calcination, connect to each other, resulting in a true, fully connected (except possible defects) three-dimensional zeolite framework with a very low density. Additionally, it features triple four-ring units not seen before in any type of zeolite. The silicate expansion-condensation approach we report may be amenable to further extra-large-pore zeolite formation. Ti can be introduced in this zeolite, leading to a catalyst that is active in liquid-phase alkene oxidations involving bulky molecules, which shows promise in the industrially relevant clean production of propylene oxide using cumene hydroperoxide as an oxidant.
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Boron-based catalysts exhibit high alkene selectivity in oxidative dehydrogenation of propane (ODHP) but the mechanistic understanding remains incomplete. In this work, we show that the hydroxylation of framework boron species via steaming not only enhances the ODHP rate on both B-MFI and B-BEA, but also impacts the kinetics of the reaction. The altered activity, propane reaction order and the activation energy could be attributed to the hydrolysis of framework [B(OSi≡)3] unit to [B(OSi≡)3-x(OH···O(H)Si≡)x] (x = 1, 2, "···" represents hydrogen bonding). DFT calculations confirm that hydroxylated framework boron sites could stabilize radical species, e.g., hydroperoxyl radical, further facilitating the gas-phase radical mechanism. Variations in the contributions from gas-phase radical mechanisms in ODHP lead to the linear correlation between activation enthalpy and entropy on borosilicate zeolites. Insights gained in this work offer a general mechanistic framework to rationalize the kinetic behavior of the ODHP on boron-based catalysts.
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Various dissipative soliton solutions exist in the parameter space of mode-locked fiber lasers, including both coherent and incoherent pulses. Novel ultrafast laser designs can lead to distinctive dissipative soliton solutions formed by unique pulse shaping dynamics in the same cavity. However, transitionary states in between steady-state mode-locked regimes remain largely unexplored. Here, we investigate the intermediate transition dynamics in a versatile Tm-doped fiber laser capable of emitting both dissipative solitons with anomalous-dispersion and normal-dispersion pulse-shaping mechanisms by adjusting an intracavity polarization controller. Real-time pulse dynamics during mode-locking transitions are analyzed with a modified dispersive Fourier transform setup, illustrating characteristic pulse shaping mechanisms typically reserved for different dispersion regimes. Combined with a spectral intensity correlation analysis, the coherence evolution between two distinct mode-locked states is fully resolved for the first time.
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Recognizing the structure and nature of the nuclei for zeolites crystallization on an atomic level is of great importance, which can provide guidance on the control of crystallization kinetics and the rational synthesis of zeolites. However, it remains a long-standing challenge due to the difficulty in characterization of amorphous precursor with limited crystal nuclei. Herein, a top-down synthesis system was designed for SAPO-34 molecular sieve and well investigated. A clear precursor solution with abundant SAPO-34 crystal nuclei was obtained under a depolymerization-dominant condition. The species in the liquid precursor were identified by FT-ICR MS, solid-state MAS NMR and atomic pair distribution function analyses. In combination with various designed experiments, it is revealed that both the formation of small species containing Si-O-Al bonds and reaching a certain concentration, is crucial for driving the crystallization of SAPO-34, rather than structural units with specific spatial conformation. This work provides an important understanding on the (pre)nucleation of SAPO-34 and sheds light on the synthesis control of SAPO molecular sieves.
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Diffusion limitation and acid deficiency are two main challenges that the ZSM-48 zeolite faces in practical application. To date, there have been few effective strategies to solve both problems, simultaneously. Also, it is also a challenge to construct a hollow structure in a one-dimensional (1D) zeolite. Herein, an Al-rich ZSM-48 zeolite with a hollow structure is constructed through an alumination-recrystallization strategy, thereby solving the problems related to diffusion and acidity simultaneously. The hollowness and enrichment of aluminum can be controlled by judiciously matching the desilication and recrystallization. The silica to alumina ratio (SAR) of the ZSM-48 zeolite can be tuned from 130 to 45, which breaks the SAR limitation of conventional synthesis. On the basis of the different characterization results, the whole crystallization can be divided into two stages: rapid desilication-alumination and time-consuming recrystallization. In the selective desilication-recrystallization process, the preferential special distribution of the organic template leads to the formation of a hollow structure and the healing of mesopores at the outer shell, as evidenced by structured illumination microscopy images. Due to the enhancement in diffusion ability and acid density, the obtained hollow Al-rich ZSM-48 zeolite exhibits excellent catalytic stability and high p-xylene yield (â¼26%) in the m-xylene isomerization reaction (WHSV = 18 h-1), indicating its strong industrial application potential.
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Part of tetrahedral framework aluminum in a protonic mordenite (HMOR) will convert geometry to distorted tetrahedral and octahedral coordination. High-field 27 Alâ NMR data show that more framework Al atoms at T3 and T4 sites change geometry to nonframework structures than others. These nonframework Al species preferentially reside in the side pockets, which will decrease the accessibility of acid sites in the 8-membered ring (MR) channel, impairing the dimethyl ether (DME) carbonylation reaction. The arisen octahedrally coordinated Al species are framework-associated, which can be reverted into the zeolite framework. Herein, we find that a facile treatment with pyridine could force the octahedral coordination Al back into a tetrahedral environment, which could increase the number of available active sites and enhance the diffusion of DME, thus improving the reactivity (4 times) of the DME carbonylation reaction and prolonging the lifetime of catalysts.
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It is of great significance to accurately quantify the Brønsted acid sites (BASs) at different positions of mordenite (MOR) zeolite. However, H-MOR obtained from Na-MOR can hardly avoid dealumination under hydrothermal conditions, which causes difficulty in the acid characterization. Herein, 23Na-27Al D-HMQC was performed combined with high-field 23Na MQ MAS NMR and DFT calculation, which provided an unambiguous attribution of the 23Na chemical shifts and further helped to improve the resolution of 27Al MAS NMR. By fitting the 23Na and 1H MAS NMR spectra of Na/H-MOR, the intrinsic BAS contents in different T-sites were measured by characterizing the location and content of sodium ions. These Na/H-MOR zeolites with various acid distributions were used for DME carbonylation and showed that the amount of BASs in the T3 site was proportional to the activity of carbonylation. This study provides a new method for investigating the intrinsic acid properties of zeolites.
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Laser cavities which can generate different types of ultrashort pulses are attractive for practical applications and the study of pulse dynamics. Here, we report the first experimental observation of both conventional solitons (CS) and dissipative solitons (DS) generated from a single all-fiber laser with net-anomalous dispersion. A birefringence-related intracavity Lyot filter with an adjustable extinction ratio enables the switching between the two types of ultrashort pulses. Depending on the polarization controller settings and the pump power, either chirp-free CS with a pulse energy of 406 pJ and a spectral bandwidth of 5.1 nm or up-chirped DS with a pulse energy of 5.1 nJ and an optical bandwidth of 9.6 nm can be generated. Similar polarization features are observed when the laser switches between different soliton operations as both CS and DS are group-velocity-locked vector solitons. Our work paves a novel way to generate dissipative solitons with a relatively high pulse energy (one order of magnitude larger than for CS) and a large chirp directly from an all-fiber net-anomalous-dispersion cavity through birefringent filter management.
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The evolution of soliton pulses into noise-like pulses in a nonlinear fiber externally to the laser oscillator is demonstrated at 1.9 µm, for the first time. Soliton collapse based mechanisms induce noise-like pulses with varying properties as a function of nonlinear fiber length without requiring any laser cavity feedback. The proposed method allows the generation of noise-like pulses with a sub-300 fs spike and sub-40 ps pedestal duration. Power scaling of the noise-like pulses is demonstrated in a double-clad thulium-doped fiber amplifier with amplification up to an average power of 5.19 W, corresponding to a pulse energy of 244 nJ. This method provides an alternative route for generating fully synchronized noise-like pulses and solitons in the same system, without relying on the conventionally used mechanism of changing the intracavity nonlinearity within the laser cavity.
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High-silica zeolite Y (FAU) plays a vital role in (petro)chemical industries. However, the slow nucleation and growth kinetics of the high-silica FAU framework limit its direct synthesis and the improvement of framework SiO2 /Al2 O3 ratio (SAR). Here, a facile strategy is developed to realize the fast crystallization of high-silica zeolite Y, which involves the combination of high crystallization temperature, ultra-stable Y (USY) seeds and efficient organic-structure directing agent (OSDA). The synthesis can be finished in 5-16â h at 160 °C and with tunable SAR up to 18.2, and the key factors affecting crystallization kinetics and phase purity are elucidated. Moreover, the crystallization process was monitored to reveal the fast crystal growth mechanism. The high-silica products possess high (hydro)thermal stability and abundant strong acid sites, which endow them excellent catalytic cracking performance, obviously superior to commercial USY.
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Controlling the location of aluminum atoms in a zeolite framework is critical for understanding structure-performance relationships of catalytic reaction systems and tailoring catalyst design. Herein, we report a strategy to preferentially relocate mordenite (MOR) framework Al atoms into the desired T3 sites by low-pressure SiCl4 treatment (LPST). High-field 27 Al NMR was used to identify the exact location of framework Al for the MOR samples. The results indicate that 73 % of the framework Al atoms were at the T3 sites after LPST under optimal conditions, which leads to controllably generating and intensifying active sites in MOR zeolite for the dimethyl ether (DME) carbonylation reaction with higher methyl acetate (MA) selectivity and much longer lifetime (25â times). Further research reveals that the Al relocation mechanism involves simultaneous extraction, migration, and reinsertion of Al atoms from and into the parent MOR framework. This unique method is potentially applicable to other zeolites to control Al location.
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Diffusion is an extremely critical step in zeolite catalysis that determines the catalytic performance, in particular for the conversion of bulky molecules. Introducing interconnected mesopores and macropores into a single microporous zeolite with the rationalized pore size at each level is an effective strategy to suppress the diffusion limitations, but remains highly challenging due to the lack of rational design principles. Herein, we demonstrate the first example of boosting molecular diffusion by constructing hierarchical Murray zeolites with a highly ordered and fully interconnected macro-meso-microporous structure on the basis of the generalized Murray's Law. Such a hierarchical Murray zeolite with a refined quantitative relationship between the pore size at each length scale exhibited 9 and 5 times higher effective diffusion rates, leading to 2.5 and 1.5 times higher catalytic performance in the bulky 1,3,5-triisopropylbenzene cracking reaction than those of microporous ZSM-5 and ZSM-5 nanocrystals, respectively. The concept of hierarchical Murray zeolites with optimized structural features and their design principles could be applied to other catalytic reactions for maximized performance.
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The traditional zeolites used in air separation are generally N2-selective adsorbents. It was found for the first time that the O2/N2 adsorption selectivity can be reversed by directly decorating the Ce metal ion sites of a traditional Y zeolite with imidazole molecules, which results in a novel O2 adsorbent. The O2/N2 selectivity changes from 0.9 to 1.6 under normal conditions, and most importantly, the O2 adsorbent is recyclable. The in situ XPS characterization results indicate that the imidazole modification can change the electronic state of Ce in the Y zeolite and increase its affinity for O2, which is confirmed by theoretical calculations. Dynamic breakthrough adsorption experiments show that the adsorbent has significant application potential in air separation.
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Hierarchical zeolites are regarded as promising catalysts due to their well-developed porosity, increased accessible surface area, and minimal diffusion constraints. Thus far, the focus has been on the creation of mesopores in zeolites, however, little is known about a microporosity upgrading and its effect on the diffusion and catalytic performance. Here the authors show that the "birth" of mesopore formation in faujasite (FAU) type zeolite starts by removing framework T atoms from the sodalite (SOD) cages followed by propagation throughout the crystals. This is evidenced by following the diffusion of xenon (Xe) in the mesoporous FAU zeolite prepared by unbiased leaching with NH4 F in comparison to the pristine FAU zeolite. A new diffusion pathway for the Xe in the mesoporous zeolite is proposed. Xenon first penetrates through the opened SOD cages and then diffuses to supercages of the mesoporous zeolite. Density functional theory (DFT) calculations indicate that Xe diffusion between SOD cage and supercage occurs only in hierarchical FAU structure with defect-contained six-member-ring separating these two types of cages. The catalytic performance of the mesoporous FAU zeolite further indicates that the upgraded microporosity facilitates the intracrystalline molecular traffic and increases the catalytic performance.