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This study aims to explore the inhibitory effect of daidzein on macrophage inflammation induced by high glucose via regulating the NOD-like receptor protein 3(NLRP3) inflammasome signaling pathway. The cell counting kit-8(CCK-8) assay was employed to detect the effects of daidzein at different concentrations on the viability of RAW264.7 cells. Western blot was employed to determine the protein level of tumor necrosis factor(TNF)-α in macrophages exposed to different concentrations of glucose for different time periods as well as the expression levels of proteins involved in the polarization and Toll-like receptor 4(TLR4)-myeloid differentiation factor(MyD88)-NLRP3 inflammasome pathway of the macrophages exposed to high glucose. Enzyme-linked immunosorbent assay was employed to measure the levels of TNF-α, interleukin(IL)-18, and IL-1ß secreted by macrophages. The expression level of nuclear factor-kappa B(NF-κB) p65 in macrophages exposed to high glucose was detected by immunofluorescence, and the level of intracellular reactive oxygen species(ROS) was detected by the DCFH-DA fluorescent probe. The mRNA levels of NLRP3, TNF-α, and IL-18 in macrophages were determined by qRT-PCR. The results showed that treatment with 30 mmol·L~(-1) glucose for 48 h was the best condition for the modeling of macrophage injury. Compared with the blank group, the model group showed improved polarization of macrophages, increased secretion of TNF-α, IL-18, and IL-1ß, elevated ROS level, and up-regulated expression of NF-κB p65. In addition, the modeling up-regulated the mRNA levels of NLRP3, TNF-α, and IL-18 and the protein levels of TLR4, MyD88, NLRP3, NF-κB p65, p-NF-κB p65, I-κB, p-I-κB, ASC, pro-caspase-1, pro-IL-1ß, cleaved IL-1ß, and pro-IL-18. Compared with the model group, daidzein(10, 20, and 40 µmol·L~(-1)) lowered the levels of inflammatory cytokines and down-regulated the mRNA levels of NLRP3, TNF-α, and IL-18 as well as the protein levels of TLR4, MyD88, NLRP3, NF-κB p65, p-NF-κB p65, I-κB, p-I-κB, ASC, pro-caspase-1, pro-IL-1ß, cleaved IL-1ß, and pro-IL-18. In addition, daidzein reduced intracellular ROS. According to the available reports and the experimental results, high glucose can induce the polarization of macrophages and promote the secretion of inflammatory cytokines. Daidzein can inhibit the expression of ROS in macrophages by regulating the NLRP3 inflammasome signaling pathway, thereby reducing the inflammation of macrophages exposed to high glucose.
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Glucosa , Inflamasomas , Isoflavonas , Macrófagos , Proteína con Dominio Pirina 3 de la Familia NLR , Transducción de Señal , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Animales , Ratones , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Macrófagos/metabolismo , Transducción de Señal/efectos de los fármacos , Glucosa/efectos adversos , Isoflavonas/farmacología , Inflamasomas/efectos de los fármacos , Inflamasomas/metabolismo , Células RAW 264.7 , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Inflamación/inducido químicamente , Especies Reactivas de Oxígeno/metabolismo , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo , Factor de Necrosis Tumoral alfa/inmunología , Interleucina-1beta/genética , Interleucina-1beta/inmunología , Interleucina-1beta/metabolismo , Interleucina-18/genética , Interleucina-18/metabolismo , Interleucina-18/inmunologíaRESUMEN
Boron compound BOMes2 containing an internal B-O bond undergoes highly efficient photoisomerization, followed by sequential structural transformations, resulting in a rare eight-membered B, O-heterocycle (S. Wang, etâ al. Org. Lett. 2019, 21, 5285-5289). In this work, the detailed reaction mechanisms of such a unique carbonyl-supported tetracoordinate boron system in the first excited singlet (S1 ) state and the ground (S0 ) state were investigated by using the complete active space self-consistent field and its second-order perturbation (MS-CASPT2//CASSCF) method combined with time-dependent density functional theory (TD-DFT). Moreover, an imine-substituted tetracoordinated organic boron system (BNMes2 ) was selected for comparative study to explore the intrinsic reasons for the difference in reactivity between the two types of compounds. Steric factor was found to influence the photoisomerization activity of BNMes2 and BOMes2 . These results rationalize the experimental observations and can provide helpful insights into understanding the excited-state dynamics of heteroatom-doped tetracoordinate organoboron compounds, which facilitates the rational design of boron-based materials with superior photoresponsive performances.
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Environmental governance by photothermal materials especially for the separation of organic pollutants and regeneration of freshwater afford growing attention owing to their special solar-to-heat properties. Here, we construct a special functional nanosphere composed of an internal silica core coated by a thin carbon layer encapsulated plasmonic bimetallic FeCo2O4 spinel (SiO2@CoFe/C) by a facile self-assembled approach and tuned calcination. Through combining the advantage of bimetallic Fe-Co and carbon layer, this obtained nanosphere affords improved multiple environmental governing functions including peroxymonosulfate (PMS) activation to degrade pollutants and photothermal interfacial solar water evaporation. Impressively, fined bimetal (FeCo) species (20 nm) acted as main catalytic substance were distributed on the N-doping carbon thin layer, which favors electron transfer and reactive accessibility of active metals. The increasing treatment temperature of catalysts caused the optimization of the surface active metal species and tuning catalytic properties in the AOPs. Besides, the incorporation of Co in the SiO2@CoFe/C-700 could enable the improved PMS activation efficiency compared to SiO2@Fe/C-700 and the mixed SiO2@Co/C-700 and SiO2@Fe/C-700, hinting a synergetic promotion effect. The bimetal coupled catalyst SiO2@CoFe/C-700 affords enhanced photothermal properties compared to SiO2@Co/C-700. Furthermore, photothermal catalytic PMS activation using optimal SiO2@CoFe/C-700 was further explored in addressing stubborn pollutants including oxytetracycline, sulfamethoxazole, 2, 4-dichlorophenol, and phenol. The free radical quenching control suggests that both the sulfate radical, hydroxyl radical, superoxide radical, and singlet oxygen species are involved in the degradation, while the hydroxyl radical and singlet oxygen play a dominant role. Furthermore, the implementation of a solar-driven interfacial water evaporation model using SiO2@CoFe/C-700 was further studied to obtain freshwater regeneration (1.26 kg m-2 h-1, 76.81% efficiency), indicating the comprehensive ability of the constructed nanocomposites for treating complicated environmental pollution including organics removal and freshwater regeneration.
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Contaminantes Ambientales , Nanosferas , Carbono , Dióxido de Silicio , Oxígeno Singlete , Agua , Radical Hidroxilo , Conservación de los Recursos Naturales , Política Ambiental , Metales , FenolesRESUMEN
Trajectory planning plays a crucial role in ensuring the safe navigation of ships, as it involves complex decision making influenced by various factors. This paper presents a heuristic algorithm, named the Markov decision process Heuristic Algorithm (MHA), for time-optimized avoidance of Unmanned Surface Vehicles (USVs) based on a Risk-Sensitive Markov decision process model. The proposed method utilizes the Risk-Sensitive Markov decision process model to generate a set of states within the USV collision avoidance search space. These states are determined based on the reachable locations and directions considering the time cost associated with the set of actions. By incorporating an enhanced reward function and a constraint time-dependent cost function, the USV can effectively plan practical motion paths that align with its actual time constraints. Experimental results demonstrate that the MHA algorithm enables decision makers to evaluate the trade-off between the budget and the probability of achieving the goal within the given budget. Moreover, the local stochastic optimization criterion assists the agent in selecting collision avoidance paths without significantly increasing the risk of collision.
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Ship collision avoidance is a complex process that is influenced by numerous factors. In this study, we propose a novel method called the Optimal Collision Avoidance Point (OCAP) for unmanned surface vehicles (USVs) to determine when to take appropriate actions to avoid collisions. The approach combines a model that accounts for the two degrees of freedom in USV dynamics with a velocity obstacle method for obstacle detection and avoidance. The method calculates the change in the USV's navigation state based on the critical condition of collision avoidance. First, the coordinates of the optimal collision avoidance point in the current ship encounter state are calculated based on the relative velocities and kinematic parameters of the USV and obstacles. Then, the increments of the vessel's linear velocity and heading angle that can reach the optimal collision avoidance point are set as a constraint for dynamic window sampling. Finally, the algorithm evaluates the probabilities of collision hazards for trajectories that satisfy the critical condition and uses the resulting collision avoidance probability value as a criterion for course assessment. The resulting collision avoidance algorithm is optimized for USV maneuverability and is capable of handling multiple moving obstacles in real-time. Experimental results show that the OCAP algorithm has higher and more robust path-finding efficiency than the other two algorithms when the dynamic obstacle density is higher.
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This study aimed to examine the effect and underlying mechanism of Puerariae Lobatae Radix on insulin resistance in db/db mice with type 2 diabetes mellitus(T2DM) based on the analysis of intestinal flora. Fifty db/db mice were randomly divided into a model group(M group), a metformin group(YX group), a high-dose Puerariae Lobatae Radix group(YGG group), a medium-dose Puerariae Lobatae Radix group(YGZ group), and a low-dose Puerariae Lobatae Radix group(YGD group). Another 10 db/m mice were assigned to the normal group(K group). After continuous administration for eight weeks, body weight and blood sugar of mice were measured. Enzyme linked immunosorbent assay(ELISA) was used to detect glycosylated serum protein(GSP) and fasting serum insulin(FINS), and insulin resistance index(HOMA-IR) was calculated. The histopathological changes in the pancreas were observed by HE staining. Tumor necrosis factor(TNF)-α expression in the pancreas was detected using immunohistochemistry. The structural changes in fecal intestinal flora in the K, M, and YGZ groups were detected by 16S rRNA. Western blot was used to detect the expression of farnesoid X receptor(FXR) and takeda G protein-coupled receptor 5(TGR5) in the ileum, cholesterol 7α-hydroxylase(CYP7A1) and sterol 27α-hydroxylase(CYP27A1) in the liver, and G protein-coupled receptors 41(GPR41) and 43(GPR43) in the colon. Compared with the K group, the M group showed increased body weight, blood sugar, serum GSP, fasting blood glucose(FBG), and FINS, increased HOMA-IR, inflammatory infiltration of islet cells, necrosis and degeneration of massive acinar cells, unclear boundary between islet cells and acinar cells, disturbed intestinal flora, and down-regulated FXR, TGR5, CYP7A1, CYP27A1, GPR41, and GPR43. Compared with the M group, the YX, YGG, YGZ, and YGD groups showed decreased body weight, blood sugar, serum GSP, FBG, and FINS, islet cells with intact and clumpy morphology and clear boundary, necrosis of a few acinar cells, and more visible islet cells. The intestinal flora in the YGZ group changed from phylum to genus levels, and the relative abundance of intestinal flora affecting the metabolites of intestinal flora increased. The protein expression of FXR, TGR5, CYP7A1, CYP27A1, GPR41, and GPR43 increased. The results show that Puerariae Lobatae Radix can improve the inflammatory damage of pancreatic islet cells and reduce insulin resistance in db/db mice with T2DM. The mechanism of action may be related to the increase in the abundance of Actinobacteria, Bifidobacterium, and Bacteroides in the intestinal tract and the protein expression related to metabolites of intestinal flora.
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Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Resistencia a la Insulina , Pueraria , Ratones , Animales , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/genética , Pueraria/química , ARN Ribosómico 16S , Peso Corporal , NecrosisRESUMEN
The first reversible photoisomerization between a borepin and a borirane was reported in the photo-induced reactions of B(npy)Ar2 (npy=2-(naphthalen-1-yl) pyridine, Ar=phenyl or electron rich aryl; S. Wang, etâ al. Angew. Chem. Int. Ed. 2019, 58, 6683-6687). In this work, the detailed mechanisms of the unprecedented reversible photoisomerization between the borepin (compound a) and the borirane (compound b) of B(npy)Ph2 in the first excited singlet (S1 ) state and the ground (S0 ) state were studied by carrying out calculations with the complete active space self-consistent field (CASSCF) and its second-order perturbation (CASPT2) methods combined with time-dependent density functional theory (TD-DFT). The calculation results show that photoexcitation of a-S0 at 365â nm and b-S0 at 450â nm populate their S1 state with evident charge transfer characteristics. The photoisomerization is triggered in the S1 state and ends in the S0 state, at which the intersection points in a (S1 /S0 )x intersection seam participate in and promote phenyl migration and ring-closure processes. Furthermore, we reveal that the not large energy difference (less than 0.6â eV) and similar conjugation properties of π electrons between a-S0 and b-S0 are responsible for their unique photo-reversible reactivity, compared with those of the isomers of the thermally reversible compound B(ppy)Mes2 . Our results contribute to an understanding of the excited-state reactivity of organoboron compounds and will be useful to support the design of new boron-based photo-responsive materials.
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This study deciphered the mechanism of Shenling Baizhu Powder in treatment of mouse model of ulcerative colitis(UC) via NOD-like receptor thermoprotein domain 3(NLRP3) signaling pathway. After three days of adaptive feeding, 70 SPF-grade BALB/c mice were randomized into 7 groups: normal group, model group(dextran sodium sulfate, DSS), mesalazine group(DSS + 5-aminosalicylic acid, 5-ASA), NLRP3 inhibitor group(DSS + MCC950), and high-, medium-, and low-dose Shenling Baizhu Powder groups(DSS + high-, medium-, and low-dose Shenling Baizhu Powder), with 10 mice per group. The normal group had free access to double distilled water, and the remaining groups had free access to DSS-containing water to establish the acute UC model. Intragastric administration was started at the same time as modeling for one week. During the experiment, the general mental state and disease activity of each group of mice were recorded and scored. After the experiment, colon and serum samples were collected. The pathological changes in colon tissue were observed through hematoxylin-eosin(HE) staining. Enzyme-linked immunosorbent assay(ELISA) was employed to determine the levels of interleukin-18(IL-18) and myeloperoxidase(MPO) in colon tissue and interleukin-1ß(IL-1ß) in serum. Immunofluorescence(IF) and immunohistochemistry(IHC) methods were employed to examine the expression of NLRP3 and IL-18 in colon tissue. Western blot was employed to measure the protein levels of NLRP3, apoptosis-associated speck-like protein(ASC), cystein-aspartate protease 1(caspase-1), and downstream inflammatory cytokines in colon tissue. Compared with the normal group, the modeling of UC increased the disease activity index(DAI), colon pathological injury score, IL-1ß level in serum, and IL-18 and MPO levels in colon tissue(P<0.05, P<0.01). Furthermore, the modeling caused obvious pathological changes and up-regulated the expression of NLRP3, caspase-1, ASC, pro-IL-1ß, cleaved-IL-1ß, pro-IL-18, and cleaved-IL-18 in the colon(P<0.01). Compared with the model group, the administration of corresponding drugs decreased the DAI, pathological injury score, IL-1ß level in serum, and IL-18 and MPO levels in colon tissue, and down-regulated the protein levels of NLRP3, caspase-1, ASC, pro-IL-1ß, cleaved-IL-1ß, pro-IL-18, and cleaved-IL-18 in the colon(P<0.05, P<0.01). According to the results of previous study and this study, we concluded that Shenling Baizhu Powder can alleviate the inflammatory response and intestinal damage of DSS-induced UC by regulating the expression of the proteins and inflammatory cytokines associated with NLRP3 signaling pathway.
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Colitis Ulcerosa , Colitis , Ratones , Animales , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/tratamiento farmacológico , Sulfato de Dextran/efectos adversos , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Interleucina-18/genética , Polvos , Colon/metabolismo , Caspasa 1 , Mesalamina/efectos adversos , Ratones Endogámicos BALB C , Modelos Animales de Enfermedad , Citocinas/metabolismo , Agua , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colitis/patologíaRESUMEN
It is still challenging to design a stable and efficient catalyst for visible-light CO2 reduction. Here, Er3+ single atom composite photocatalysts are successfully constructed based on both the special role of Er3+ and the special advantages of Zn2 GeO4 /g-C3 N4 heterojunction in the photocatalysis reduction of CO2 . Especially, Zn2 GeO4 :Er3+ /g-C3 N4 obtained by in situ synthesis is not only more conducive to the tight junction of Zn2 GeO4 and g-C3 N4 , but also more favorable for g-C3 N4 to anchor rare-earth atoms. Under visible-light irradiation, Zn2 GeO4 :Er3+ /g-C3 N4 shows more than five times enhancement in the catalytic efficiency compared to that of pure g-C3 N4 without any sacrificial agent in the photocatalytic reaction system. A series of theoretical and experimental results show that the charge density around Er, Ge, Zn, and O increases compared with Zn2 GeO4 :Er3+ , while the charge density around C decreases compared with g-C3 N4 . These results show that an efficient way of electron transfer is provided to promote charge separation, and the dual functions of CO2 molecular activation of Er3+ single atom and 4f levels as electron transport bridge are fully exploited. The pattern of combining single-atom catalysis and heterojunction opens up new methods for enhancing photocatalytic activity.
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All-nitrogen salts have attracted extensive attention because of their unique chemical, physical properties, and potential applications as high-energy density materials. Using first-principles calculations and a particle swarm optimization structure search method, the pressure versus composition phase diagram of the Sc-N system is established. A new stable phase of C2/m-ScN5 with the intriguing 2D N106- is identified for the first time and we also found ScN3 with the P1[combining macron] structure which has been reported before. Under ambient conditions, both of them have high kinetic and thermodynamic stability with high energy density (2.40 kJ g-1 and 4.23 kJ g-1 relative to ScN and N2 gas). The analyses of chemical bonding pattern indicate that the nitrogen atoms in the N66- chains are connected by covalent bonds with a combined σ and π bond character. We also give a possible high-pressure experimental route to P1[combining macron]-ScN3 and C2/m-ScN5 at modest pressure. We expect that our theoretical research could encourage experimental realization in the future and contribute to the understanding of the bonding features of nitrogen chains.
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As the first discovered organoboron compound with photochromic property, B(ppy)Mes2 (ppy=2-phenylpyridine, Mes=mesityl) displays rich photochemistry that constitutes a solid foundation for wide applications in optoelectronic fields. In this work, we investigated the B(ppy)Mes2 to borirane isomerization mechanisms in the three lowest electronic states (S0 , S1 , and T1 ) based on the complete active space self-consistent field (CASSCF) and its second-order perturbation (CASPT2) methods combined with time-dependent density functional theory (TD-DFT) calculations. Our results show that the photoisomerization in the S1 state is dominant, which is initiated by the cleavage of the B-Cppy bond. After overcoming a barrier of 0.5â eV, the reaction pathway leads to a conical intersection between the S1 and S0 states (S1 /S0 )x , from which the decay path may go back to the reactant B(ppy)Mes2 via a closed-shell intermediate (Int1-S0 ) or to the product borirane via a biradical intermediate (Int2-S0 ). Although triplet states are probably involved in the photoinduced process, the possibility of the photoisomerization in T1 state is very small owing to the weakly allowed S1 âT1 intersystem crossing and the high energy barrier (0.77â eV). In addition, we found the photoisomerization is thermally reversible, which is consistent with the experimental observations.
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The finite-difference time-domain method is employed to study the light extraction efficiency of white light emitters. The cone arrays designed on top of white light emitters eliminate the dependency of light extraction on the wavelength and the cavity thickness and that leads to significant enhancement in light extraction efficiency for whole visible light spectrum. The light extraction efficiency of 81% has been achieved. Most importantly, the high extraction efficiency is achieved for the whole visible spectrum from 400 nm to 700 nm. This work will provide guidelines for designing highly efficient white light emitters for general illumination and display purpose.
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Herein, the complete active space self-consistent field (CASSCF) and its second-order perturbation (CASPT2) methods combined with time-dependent density functional theory (TD-DFT) calculations were employed to investigate the isomerization reaction mechanisms of an asymmetric N,C-chelate organoboron compound, B(ppy)MesPh, in the ground (S0) state and the first singlet excited (S1) state. Our calculations show that isomerizations proceed via different pathways in the S0 and S1 states,; however, the energy barriers for mesityl isomerization are higher than those for phenyl isomerization in both states; this is in good agreement with the experimentally observed regioselectivity (S. Wang, et al. Angew. Chem., Int. Ed., 2017, 56, 6093-6097). Photoisomerization is motivated by charge transfer from two phenyl rings to the pyridyl moiety and initiated by the cleavage of the B-Cppy bond, followed by the formation of a boracyclopropane ring via an (S1/S0)X conical intersection and a biradical intermediate. Both steric and electronic features were found to be important for regioselective photoisomerization. Our results not only shed light on the experimental observations, but also provide valuable details on the excited state dynamics of organoboron compounds and can facilitate further syntheses and applications.
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In this work, a hybrid of chromium(III) terephthalate metal organic framework (MIL-101) and graphene oxide (GO) was synthesized and its performance in the removal of azo dyes (Amaranth, Sunset Yellow, and Carmine) from water was evaluated. The adsorption for azo dyes on MIL-101/GO was compared with that of MIL-101, and it was found that the addition of GO enhanced the stability of MIL-101 in water and increased the adsorption capacity. The maximum adsorption capacities of MIL-101/GO were 111.01 mg g(-1) for Amaranth, 81.28 mg g(-1) for Sunset Yellow, and 77.61 mg g(-1) for Carmine. The adsorption isotherms and kinetics were investigated, showing that the adsorption fits the Freundlich isotherm and the pseudo-second-order kinetic model. The recyclability of MIL-101/GO was shown by the regeneration by acetone. The high adsorption capability and excellent reusability make MIL-101/GO a competent adsorbent for the removal dyes from aqueous solution.
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Colorante de Amaranto/química , Compuestos Azo/química , Carmín/química , Compuestos de Cromo/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Adsorción , Colorantes , Grafito/química , Concentración de Iones de Hidrógeno , Cinética , Metales , Óxidos , AguaRESUMEN
The effect of high pressure on the crystal structure of thiourea dioxide has been investigated by Raman spectroscopy and angle-dispersive X-ray diffraction (ADXRD) in a diamond anvil cell up to 10.3 GPa. The marked changes in the Raman spectra at 3.7 GPa strongly indicated a structural phase transition associated with the distortions of hydrogen bonding. There were no further changes up to the maximum pressure of 10.3 GPa and the observed transition was completely reversible when the system was brought back to ambient pressure. This transition was further confirmed by the changes of ADXRD spectra. The high-pressure phase was indexed and refined to an orthorhombic structure with a possible space group Pbam. The results from the first-principles calculations suggested that this phase transition was mainly related to the changes of hydrogen-bonded networks in thiourea dioxide.
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Disordered structures of boron nitride (BN), graphite, boron carbide (BC), and boron carbon nitride (BCN) systems are considered important precursor materials for synthesis of superhard phases in these systems. However, phase transformation of such materials can be achieved only at extreme pressure-temperature conditions, which is irrelevant to industrial applications. Here, the phase transition from disordered nanocrystalline hexagonal (h)BN to superhard wurtzitic (w)BN was found at room temperature under a pressure of 6.7 GPa after applying large plastic shear in a rotational diamond anvil cell (RDAC) monitored by in situ synchrotron X-ray diffraction (XRD) measurements. However, under hydrostatic compression to 52.8 GPa, the same hBN sample did not transform to wBN but probably underwent a reversible transformation to a high-pressure disordered phase with closed-packed buckled layers. The current phase-transition pressure is the lowest among all reported direct-phase transitions from hBN to wBN at room temperature. Usually, large plastic straining leads to disordering and amorphization; here, in contrast, highly disordered hBN transformed to crystalline wBN. The mechanisms of strain-induced phase transformation and the reasons for such a low transformation pressure are discussed. Our results demonstrate a potential of low pressure-room temperature synthesis of superhard materials under plastic shear from disordered or amorphous precursors. They also open a pathway of phase transformation of nanocrystalline materials and materials with disordered and amorphous structures under extensive shear.
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Alkali metal azides can be used as starting materials in the synthesis of polymeric nitrogen, a potential high-energy-density material. The structural evolutionary behaviors of nitrogen in CsN3 have been studied up to 200 GPa using particle swarm optimization structure search combining with density functional theory. Three stable new phases with C2/m, P21/m, and P-1 structure at pressure of 6, 13, and 51 GPa are identified for the first time. The phase transition to chain like structure (P-1 phase) occurs at a modest pressure 51 GPa, the azide ions N3 (-) (linear chains of three N atoms with covalent bonds and interact weakly with each other) begin to show remarkable polymeric N properties in the CsN3 system. Throughout the stable pressure range, the structure is metallic and consists of N atoms in sp(2) hybridizations. Our study completes the structural evolution of CsN3 under pressure and reveals that the introduced Cs atoms are responsible for the decreased synthesis pressure comparing to pure molecular nitrogen under compression.
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In this study, high pressure infrared (IR) absorption and Raman scattering studies for ammonium azide (NH4N3) were carried out at room temperature up to 20 GPa and 22 GPa, respectively. For comparison and further assignment, the vibrational spectra at ambient conditions were calculated using CASTEP code, particularly for the far- and mid-IR modes. The recorded vibrational data consistently indicated a pressure-induced phase transition at 2.9 GPa. All observed vibrational modes maintained their identities at the high pressure phase, indicating that NH4N3 was still presented in the form of ammonium cations and azide anions linked by the hydrogen bond (N-Hâ¯N). Above 2.9 GPa, the relative magnitude of the torsional mode weakened and the N-H symmetric stretch displayed a redshift, indicating strengthened hydrogen bonding energy. The opposite effects were observed above 12 GPa, where the relative magnitude of the torsional mode strengthened and the N-H symmetric stretch reverted to a blueshift, indicating weakened hydrogen bonding energy. It can be concluded that the hydrogen bonding energy exhibited a weakening (0-2.9 GPa), strengthening (2.9-12 GPa), and then again weakening (12-22 GPa) phenomena with the increasing of compression. The hydrogen bonding energy changing with the increase of pressure can be ascribed to a phase transition at 2.9 GPa and a rotational or bending behavior of azide ions at 12 GPa.
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The dysfunction of pancreatic ß-cells plays a pivotal role in the pathogenesis of type 2 diabetes mellitus (T2DM). Despite numerous studies demonstrating the anti-inflammatory and antioxidant properties of puerarin, the protective effects of puerarin on ß-cells remain poorly understood. Hence, this study aimed to explore the effects of puerarin on ß-cell dysfunction in a hyperglycemic environment via the PINK/Parkin-mediated mitochondrial autophagy pathway. The alterations in cell viability of MIN6 cells exposed to glucose concentrations of 5 mM, 10 mM, 20 mM, and 30 mM for 24 h, 48 h, and 72 h, respectively, were assessed using the CCK-8 assay to optimize the modeling conditions. Subsequently, cellular insulin secretion was measured using enzyme-linked immunosorbent assay (ELISA), apoptosis rate by flow cytometry, mitochondrial membrane potential alteration by JC-1, cellular ROS production by the DCFH-DA fluorescent probe, and fusion of cellular autophagosomes and lysosomes through adenoviral infection analysis. Furthermore, gene and protein expression levels of the PINK/Parkin-mediated mitochondrial autophagy pathway and mitochondrial apoptosis pathway were assessed using real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot, respectively. Results indicated a significant decrease in MIN6 cell viability following 48 h of exposure to 30 mM glucose concentration. Puerarin intervention markedly attenuated ROS production, restored mitochondrial membrane potential, induced PINK/Parkin-mediated mitochondrial autophagy, suppressed activation of the mitochondrial apoptotic pathway, mitigated apoptosis, and enhanced insulin secretion in a high glucose (HG) environment. The findings of this investigation contribute to a deeper understanding of the precise mechanism underlying the protective effects of puerarin on ß-cells and offer a theoretical foundation for advancing puerarin-based therapeutics aimed at ameliorating T2DM.
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Growing attention has been paid to the rational treatment of antibiotics-bearing medical wastewater. However, the complexity of polluted wastewater makes the later comprehensive treatment difficult only by the Advanced Oxidation Process technique. Therefore, the coupled water treatment techniques including contaminant mineralization and regeneration of cleanwater become very attractive. A bimetallic functional hollow nanoreactor defined as (Co@SiO2/Cu-X) was successfully constructed by coating a Cu-doped silica layer on the metal-organic framework (ZIF-67) followed by programmed calcination in nitrogen. The nanoreactor was endowed with a hollow configuration composed of mesoporous N-doping C-Silica hybrid shell encapsulated ultrafine Cu and Co metallic species. Such a configuration allows for the efficient diffusion and open reaction space of big contaminant molecules. The catalytic synergy of exposed Co-Cu bimetals and the easy accessibility of electron-rich contaminants by polar N doping sites triggered surface affinity make the optimal Co@SiO2/Cu-6 afford an excellent catalytic norfloxacin mineralization activity (7â min, kabs=0.744â min-1) compared to Cu-free Co@SiO2-6 (kabs=0.493â min-1) and Co-6 (kabs=0.378â min-1) Benefiting from the above unique advantages, Co@SiO2/Cu-6 show excellent removal performance in degrading different pollutants (carbamazepine, oxytetracycline, tetracycline, and bisphenol A) and persistent recycled stability in removing NFX. In addition, by virtue of the excellent photothermal properties, interfacial solar water evaporation application by Co@SiO2/Cu-6 was further explored to reach the regeneration of cleanwater (1.595â kg m-2 h-1, 97.51 %). The integration of pollutant mineralization and solar water evaporation by creating the monolith evaporation by anchoring the Co@SiO2/Cu-6 onto the tailored melamine sponge allows the regeneration of cleanwater (1.6â kgâ m-2â h-1) and synchronous pollutant removal (NFX, 95 %, 60â min), which provides potential possibility the treatment of complicated wastewater.