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A new track-multilayer ground model was established to investigate railway subgrade dynamic responses induced by moving train load in this paper. The ground structure was modeled by an elastic layer overlying an unsaturated porous elastic half space. The dynamic governing equations of the three-phase porous medium, which are easy to be degraded to Biot's theory, were derived with consideration of both viscous drag and inertial coupling between pore fluids and soil skeleton as well as capillary pressure. The model solutions were obtained based on dynamic stiffness matrix method and Fourier transform and introducing corresponding boundary condition. The vertical displacement on the subgrade top surface and the pore water pressure along the depth were studied. The numerical results show that the effects of saturation, vehicle speed, train axle load and subgrade bed material properties on the subgrade responses are significant.

A detailed theoretical study on the mechanism and regioselectivity of the Au(I)-catalyzed intramolecular electrophilic aromatic substitution (SEAr) in 4-substituted isoxazole derivatives is reported, using two model substrates, 4-(1-methylpropargyloxy)isoxazole (Series A) and 4-(1-methyl propargylamino)isoxazole (Series B). The obtained theoretical data reveal similar energy profiles in both series for the 6-endo-dig heteroatom-assisted SEAr to form an alkenyl Au(I) intermediate. Then, in the series A, the 1,3-H-shift assisted by the 4-propargyloxyisoxazole leads to a final product and the catalyst regeneration. In contrast, in the series B, the elimination of proton by N-phenylbenzaldimine additive results in an iminium cation and dihydropyridine. In the next step, a hydride from dihydropyridine is accepted by the iminium cation to furnish pyridinium and N-benzylidenebenzenaminium species. Subsequently, protodeauration leads to a final product and N-phenylbenzylamine along with the catalyst regeneration. In the absence of N-phenylbenzaldimine additive, 4-(1-methylpropargylamino)isoxazole accepts the hydride instead of N-phenylbenzylamine and causes the consumption of the reactants, thus accounting for a low product yield. Furthermore, the regioselectivity and its origin as well as the rationalization of the deuterium labeling experiments are also examined and discussed in detail.

A detailed theoretical analysis of the mechanism and chemoselectivity for gold(I)-catalyzed reaction of o-(alkynyl)styrene containing an isopropyl and a methyl at the terminal position of the alken...

A new series of five three-dimensional Ln(III) metal-organic frameworks (MOFs) formulated as [Ln4(μ6-L)2(μ-HCOO)(μ3-OH)3(μ3-O)(DMF)2(H2O)4] n {Ln3+ = Tb3+ (1), Eu3+ (2), Gd3+ (3), Dy3+ (4), and Er3+ (5)} was successfully obtained via a solvothermal reaction between the corresponding lanthanide(III) nitrates and 2-(6-carboxypyridin-3-yl)terephthalic acid (H3L). All of the obtained compounds were fully characterized, and their structures were established by single-crystal X-ray diffraction. All products are isostructural and possess porous 3D networks of the fluorite topological type, which are driven by the cubane-like [Ln4(μ3-OH)3(μ3-O)(μ-HCOO)]6+ blocks and μ6-L3- spacers. Luminescent and sensing properties of 1-5 were investigated in detail, revealing a unique capability of Tb-MOF (1) for sensing acetone and metal(III) cations (Fe3+ or Ce3+) with high efficiency and selectivity. Apart from a facile recyclability after sensing experiments, the obtained Tb-MOF material features a remarkable stability in a diversity of environments such as common solvents, aqueous solutions of metal ions, and solutions with a broad pH range from 4 to 11. In addition, compound 1 represents a very rare example of the versatile Ln-MOF probe capable of sensing Ce3+ or Fe3+ cations or acetone molecules.

This study is devoted to a theoretical investigation of the mechanism, regioselectivity, role of catalyst, and effect of substituent and solvent in the Au-catalyzed cascade reaction between 1,4-diynes and pyrroles. Density functional theory (DFT) calculations indicate that this reaction comprises four principal stages: (1) formation of different intermediates through the first intermolecular hydroarylation, (2) 1,3-H transfer to give the enyne intermediates, (3) a second intermolecular hydroarylation, and (4) a second proton transfer along with Au(I) catalyst regeneration and final product formation. In addition, the computational results suggest that the first regioselectivity is determined by the electronic effects of the reagents. However, the torsional strains within the transition structures (intramolecular cyclization) and electronic effects of enyne intermediates would account for the second regioselectivity. A global reactivity index (GRI) analysis for different gold catalysts (namely, IPrAu+, PPh...

AIM: To compare the changes of wavefront aberrations in patients with diabetic retinopathy(DR)and with different degrees of dry eye and to explore the reasons of visual quality decline in them. METHODS: We randomly selected 40 eyes in our hospital for treatment with DR and varying degrees of dry eye, and 40 eyes of normal control group. Topcon KR-1W visual quality analyzer was used to record the mean square the total high order corneal aberration, spherical aberration, comatic aberration and trefoil aberration of cornea with pupil diameters of 4mm and 6mm. Analysis of variance were used to compare the wavefront aberrations and the aberration values in the control group and in patients with diabetic retinopathy and with different degrees of dry eye. RESULTS: For 4mm and 6mm pupil diameters, nondiabetic retinopathy(NDR)with dry eye group, the nonproliferative diabetic retinopathy(NPDR)with dry eye group and proliferative diabetic retinopathy(PDR)dry eye group had significantly increased tHOA, coma and trefoil compared with the contrast group(PPCONCLUSION: Dry eye of diabetic retinopathy with different degrees is closely related to the increase of wavefront aberration. Increased wavefront aberration may be one of the reasons to reduced visual quality in patients with diabetic retinopathy and with dry eye, and provide the basis for the decline of visual function of diabetic patients with dry eye.

The present study reports a detailed theoretical analysis of the mechanistic and chemoselectivity features in 1,6-diyne ester cycloisomerization. The energy profiles for three different catalysts, namely, [AuI(PPhMe2)(NCMe)]+, [AuIII(Cl)2(pic)] (pic = 2-picolinate), and PtCl2, were investigated. The DFT calculations reveal that all of these catalysts entail similar 1,3-acyloxy migration and 5-exo-dig cyclization steps, whereas completely distinct reaction pathways are observed after the formation of the putative vinyl metal complex intermediates. In the [AuI(PPhMe2)(NCMe)]+ system, the configuration of the phosphine ligand can explain the exclusive chemoselectivity of the Friedel–Crafts reaction over the 1,5-acyl migration. On the other hand, in the [AuIII(Cl)2(pic)] and PtCl2 systems, the 1,5-acyl migration is assisted by the chloride ligand, offering an alternative mechanism that can justify a reasonable activation barrier and the corresponding stereochemical feature in the reaction. Moreover, the [AuI(...

A trifunctional aromatic building block (H2L) containing three different types of functional groups (carboxyl C(O)OH, aldehyde C(O)H, and O-ether) was applied for the hydrothermal synthesis of two novel lanthanide 2D coordination polymers [Ln(μ-HL)(μ3-L)(phen)]n {Ln = Tb (1) and Eu (2); H2L = 5-methoxy-(4-benzaldehyde)-1,3-benzene dicarboxylic acid; phen = 1,10-phenanthroline}. Both compounds 1 and 2 are isostructural and reveal very complicated 2D metal–organic double layers with the 3,4L27 topology. The presence of free aldehyde groups positioned outside of the double layers opens up a possibility of using them as functional groups toward sensing amines and small organic molecules. The fluorescence measurements for the Tb derivative 1 reveal that it acts as an efficient fluorescence sensor for p-phenylenediamine, benzidine and acetone molecules via a luminescence quenching effect. A similar sensing behavior was observed for the Eu compound 2. Moreover, thin-films of 1-PEG on glass (1-PEG-glass thin-film material) were fabricated and investigated for the detection of amine vapors.

This study reports the first theoretical evidence for the crucial role played by SbF6− in the determination of the regioselectivity in the gold-catalyzed cycloisomerization of ortho-(phenylethynyl) styrenes. According to our calculations, irrespective of using α-substituted or β,β-disubstituted o-(phenylethynyl) styrene, a novel and unusual reaction pathway for elimination of protons involving a four-center-three-electron intermediate, instead of the generation of HSbF6, is observed. On account of the electronic effect, the ring expansion pathway is more favorable than the elimination pathway for α-substituted o-(phenylethynyl) styrene. By using β,β-disubstituted o-(phenylethynyl) styrene, an elimination pathway involving the four-center-three-electron intermediate affords the indenyl derivative. Based on our calculation results and experimental facts, the regioselectivity for the title reaction is mainly controlled by electronic effects rather than steric effects. The theoretical results not only well rationalize the experimental observations but also provide insights into the details of the reaction.

By means of density functional theory (DFT), the mechanism and role of GaCl3 and aldehydes for the GaCl3-mediated reaction of donor–acceptor (D–A) cyclopropanes and arylaldehydes have been reported in this work. DFT calculations reveal that the title reaction proceeds through three main steps: (1) the isomerization of 2-arylcyclopropane-1,1-dicarboxylates r1 to generate the ethylidenemalonate gallium complex 1a or 2-styrylmalonates 1b. (2) Subsequently, reaction between 1a (or 1b) and aromatic aldehydes would induce the formation of substituted indenes (Stage I). (3) Finally, reaction between the formed substituted indenes and aromatic aldehydes would give the polycyclic lactones (Stage II). According to our calculation, aldehydes not only participate in the reaction as a reactant, they can also promote the reaction as a co-catalyst for their proton-shuttle feature. For this reason, some excess of aldehyde is essential for implementing the process. The excess GaCl3 will hydrolyze with the water formed in Stage I, which ensures that the reaction of Stage II is carried out under acidic conditions. Furthermore, the usual [3 + 2] cycloaddition of DACs with aromatic aldehydes has also been studied. The theoretical results not only well rationalize the experimental observations but provide insights into the details of the reaction.

In this study, the mechanism and stereoselectivity in the B(C6F5)3-catalyzed cyclopropanation of styrenes and aryldiazoacetates were studied by the density functional theory (DFT), revealing a number of important observations. (1) The whole reaction entails the coordination of B(C6F5)3 to the Lewis basic ester site on diazo compound, generating an alkene diazonium species. Loss of dinitrogen affords a resonance stabilized Lewis acid-activated carbene intermediate, which then undergoes a concerted [2 + 1] cycloaddition with styrene to yield a S-isomeric product and regenerate the catalyst. (2) Additional calculation results for E/Z-β-methyl styrene and allyl 4-bromophenyldiazoacetate also support the concerted pathway. (3) For tosylvinylindole substrate, the reaction tends to produce a cyclopropane of the olefin rather than the C H insertion product or cyclopropanation of the 2,3-bond of the indole unit. (4) The calculation results for three ineffective diazo substrates indicate that the activation free energy for the formation of Lewis acid-activated carbene is too high to conduct further reaction. In addition, the distortion/interaction analysis showed that the chemoselectivity of cyclopropanation (C1 or C2) and C H functionalization were entirely determined by the distortion energy, while the stereoselectivity is influenced by the interaction and distortion energies. The obtained results can be of particular significance in homogeneous catalysis toward the design and prediction of organocatalytic molecular systems and [2 + 1] cycloaddition transformations involving alkenes and diazo derivatives.

The hydroxy-aluminum solution is prepared by alkali neutralization titration and the subsequent cross-linking tests are designed by mixing the hydroxy-aluminum solution and expansive soil, followed by the discussion on the influence of the molar ratio of OH- to Al3+ and ratio of total aluminum to expansive soil on the swelling behavior of the cross-linked soil. The free swelling ratio of the cross-linked soil decreased significantly, indicating that the main aluminum species that changes the expansion properties of the cross-linked soil is [Al13]7+.

This study reports a detailed theoretical analysis of the mechanisms and chemoselectivity for the formation of benzo[b]fluorenes or benzofulvenes from propargyl esters catalyzed by an organometallic Au(I) complex. Three different substitution patterns within the 1,5-diyne ester substrates were explored to rationalize the reaction mechanism and chemoselectivity. DFT calculations reveal that the title reaction proceeds through four main steps: (i) 1,3-acyl-shift, (ii) 6-endo-dig or 5-exo-dig cyclization, (iii) Friedel–Crafts-type, and (iv) proton transfer, with step (ii) being rate-determining in all studied pathways. In the absence of substituents at the aromatic rings of the substrate (R = H), the 6-endo-dig cyclization is favored. In turn, in the presence of one strong electron-donating substituent at the backbone (R = OCH3) of the substrate, the 5-exo-dig cyclization is favored. Besides, a modification of the substrate’s acetyl group by a pivaloyl group leads to an activation barrier difference between ...

Subgrade long-term deformation was investigated by taking the effects of both traffic load and drying–wetting cycles into consideration on the basis of numerical calculation and laboratory ...

Atopic dermatitis (AD) is a chronic inflammatory skin disease which is often associated with Staphylococcus aureus (S. aureus) colonization. S. aureus ingredients are potential ligands to activate the Toll-like receptor 2 (TLR2) and drive inflammatory cytokine or chemokine production. However, the role of TLR2-mediated chemokine expression in AD development has not been systematically investigated. In this study, we sought to determine the mode of TLR2-mediated chemokine expression in AD patients. Human peripheral blood mononuclear cells (PBMCs) were isolated from AD patients and healthy controls. Upon incubation with TLR2 ligands Pam3CSK4 and PGN, mRNA expression of chemokines, including CCL1, CCL5, CCL8, CCL13, CCL17, CCL18, CCL22, and CCL27, were determined by quantitative real-time polymerase chain reaction (qRT-PCR) analysis. The results showed that basal mRNA expression of CCL17 in PBMCs from AD patients was upregulated compared with healthy controls, while those of CCL8 and CCL13 were downregulated. When stimulated with TLR2 ligands, the mRNA expression of CCL5, CCL8, CCL13, CCL18, and CCL22 in PBMCs from AD patients was significantly higher than those from healthy controls. The different basal chemokine mRNA expression profiles indicate the different immune status in patients with AD compared with healthy controls. Excessive chemokine mRNA expression induced by TLR2 activation is associated with the development of AD.

C36H26N2O4Co, monolinic, C2/c (no. 15), a = 43.230(14) Å, b = 17.100(6) Å, c = 11.275(4) Å, β = 103.112(4)°, V = 8118(5) Å3, Z = 12, R gt(F) = 0.0370, wR ref(F 2) = 0.0931, T = 100(2) K.

Deafness has become one of the most frequent health problems worldwide, and affects almost every age group. Hair cell damage or absence is the main cause of hearing loss, but there is no successful treatment to heal deafness. MicroRNA (miRNA), as a highly conserved endogenous non-coding small RNA, plays an important role in inner ear cochlea and hair cell development. In this review, we elaborate on the expression and function of miRNAs in cochlear hair cell development, and reveal its indispensable important role. We summarize the molecular mechanism of miRNA in regulating transcription factors involved in cochlear hair cell development, which may provide references and insights for hair cell regeneration in vivo and cellular transplantation therapy of deafness.

A variety of axially chiral biaryldiols were synthesized in good yields with excellent atropo-enantioselectivities through construction of axially chiral indoles catalyzed by asymmetric hydrogen-bond donors. In addition, the new axially chiral compounds were proved to be efficient and practical catalysts for asymmetric catalysis. The strategy not only provides a novel method to synthesize axially chiral compounds but also extends the scope of chiral catalysts.

The Evidential Reasoning (ER) approach is an inference method to analyse multi-criteria decision-making problems with uncertainties. However, due to the pressure of time, limit of knowledge and lack of data, such problems need to be assessed using both human judgments and limited data. In this case, it is suitable to provide a belief structure by means of linguistic terms, which we refer to as linguistic belief structure. Considering that different decision-makers may have different perceptions, the semantics of human judgments can also be different. In this paper, we introduce three linguistic scale functions to capture the semantics of linguistic belief degrees for constructing a complete linguistic information fusion method. We then extend the framework of the ER approach to multi-expert multi-criteria decision making. The method proposed in this study can fill the research gap of the ER approach for multi-expert multi-criteria decision-making problems with linguistic belief structures.

Activation of RIPK1 controls TNF-mediated apoptosis, necroptosis and inflammatory pathways

This paper presents a 5G mobile communication dual-band antenna based on graphene film. The graphene film has a high conductivity of $1.1\times 10^{6}\ \mathrm{S}/\mathrm{m}$ . The new antenna has an excellent return loss of −30.02 dB and −26.09 dB at 3.5 GHz and 4.9 GHz, respectively. The −10 dB bandwidth of the antenna is 3.31 GHz to 3.81 GHz and 4.67 GHz to 5.03 GHz. In addition, the simulation results agree well with the measured results.

This paper proposes a grid voltage disturbance compensation control to improve the stability of the DFIG system under weak grid condition. A detailed impedance model of the DFIG system is developed in the d-q frame. Based on the proposed model, the relationship between the outputs of the controllers and the grid voltage disturbance at PCC can be obtained. Then, the compensation control of the grid voltage disturbance are integrated to the current control loops of RSC and GSC to improve the stability of the DFIG system connected to the weak grid. In this paper, the effective of the proposed compensation control is proved through the GNC, which illustrates that the compensation control implemented in RSC and GSC simultaneously has a better ability to maintain the stability of the DFIG system under weak grid condition than the only one side used. The simulation results verify the analysis.

This paper presents an inverted-F antenna based on graphene film for 5G mobile communications. The graphene film has a high conductivity of 1.1×106 S/m. The graphene film based inverted-F antenna with the resonant frequency of 3.48 GHz has excellent performance, which the |S 11 | is -43.2 dB and the bandwidth is from 3.08 GHz to 4.65 GHz.

The global pandemic caused by the 2019 coronavirus (COVID-19) has led to a dramatic increase in medical waste worldwide. This tremendous increase in medical waste is an important transmission medium for the virus and thus poses new and serious challenges to urban medical waste management. This study investigates the response of medical waste management to the COVID-19 pandemic and subsequent changes in Wuhan City based on the most detailed data available, including waste generation, storage, transportation, and disposal. The results show that despite a 5-fold increase in the demand for daily medical waste disposal in the peak period, the quick responses in the storage, transportation, and disposal sectors during the pandemic ensured that all medical waste was disposed of within 24 hours of generation. Furthermore, this paper discusses medical waste management during future emergencies in Wuhan. The ability of the medical waste management system in Wuhan to successfully cope with the rapid increase in medical waste caused by major public health emergencies has important implications for other cities suffering from the pandemic and demonstrates the need to establish resilient medical emergency systems in urban areas.

Field test is the most direct and essential way to evaluate subgrade dynamic responses, which is of great importance in designing and ensuring long-term subgrade performance. Many researchers have performed field tests considering the dynamic responses of subgrade. However, in the previous tests, the water content of the soil, which decides the mechanical properties of unsaturated soil, is rarely considered. In this paper, the dynamic responses of subgrade in different saturations are investigated by both field tests and analytical simulations. The vertical stress and acceleration tested in the field under different water contents, depths, truck speeds, and axle weights are presented. The result shows that as the water content in the subgrade rises, vertical stress variation is insignificant, while the amplitude of acceleration increases. According to the distribution of water content of the subgrade, a double-layer unsaturated soil model was proposed using the stiffness matrix method. The comparison between field test and simulation results shows that the agreement is good.

In this work, the hypothesis that thermoplastic polyurethane (TPU) microplastics (MPs) could form complex toxic pollution by absorbing both antibiotics and heavy metals simultaneously was proposed. The unique features of the adsorption of Cu(II) and oxytetracycline (OTC) on the pristine TPU and photo-aged (aged) TPU MPs in single and coexisting system were investigated, which included the kinetics, isothermal equilibrium and thermodynamics. The possibly synergistic or competitive effects between Cu(II) and OTC were also evaluated. The results showed that the adsorption process of Cu(II) and OTC could be described well by pseudo-second-order kinetic equation. The entire process could be divided into two stages: internal diffusion and external diffusion. The Sips model could give good fitting for the isothermal adsorption equilibrium. The thermodynamic parameters depicted the endothermic nature of adsorptions and the process was spontaneous. In the coexisting system, synergistic or competitive effects depended critically on the ratio of concentrations (Cu(II) vs OTC). When the ratio was 1:1, Cu(II) significantly enhanced the adsorption of OTC, while OTC showed a weak effect on Cu(II) adsorption. The synergies could be attributed to the formation of Cu(II)-OTC complex and the bridging effect of Cu(II). Overall, the adsorption capacity of aged TPU was higher than that of pristine TPU, which was due to the differences in morphological characteristics and functional groups. FTIR studies revealed that ester carbonyl and acylamino groups in the TPU may be involved in the adsorption of Cu(II) and OTC.

Studies concerning noncolloidally crosslinked montmorillonites (NCMs) are significant for the chemical treatment of expansive soil. In this study, NCMs with OH/Al molar ratios of 1.0, 1.5, 2.0, and 2.5 and Al/montmorillonite ratios of 0.1, 0.3, 0.5, 0.8, and 1.0 mmol g⁻¹ were prepared via AlCl₃–NaOH reactions and subsequent Al₁₃–montmorillonite interactions. The resulting NCMs exhibited the characteristics of silt as well as significant expansion and mechanical property changes. The expansion properties of the NCM samples, including the free swelling ratio, swelling force, free expansion ratio, and expansion ratio under 50 kPa all decreased significantly. According to the X-ray diffraction data, the basal spacing of the NCM samples became relatively stable and slightly expanded after the drying and rewetting processes. Additionally, the cohesive force and shear strength of the NCM samples increased significantly after the crosslinking process. Furthermore, the X-ray fluorescence spectrometry results confirmed that the Al oxide content of the NCMs increased as the swelling properties decreased, indicating that primarily the Al₁₃ groups influenced the swelling behavior of the NCMs.

Impedance-based method is an effective method to analyze the system stability. Based on the impedance stability theory, an improved virtual inductance control method considering PLL dynamic is presented for the stability of doubly-fed induction generator (DFIG) under weak grid condition. Firstly, equivalent input admittance model of the DFIG system including all its controller is developed in the synchronous reference (d-q) frame. Secondly, the generalized Nyquist criterion (GNC) proves that the stability of the DFIG system can be improved by increasing the rotor inductance. Then, a virtual inductance term is introduced into the RSC current controller to emulate additional inductance in the rotor. However, the virtual inductance method may be ineffectual due to the influence of the PLL dynamic under weak grid condition. Therefore, an improved virtual inductance control method considering the PLL dynamic is implemented to improve the stability of the DFIG system under weak grid condition, and the simulation is used to verify the effectiveness of the improved virtual inductance control strategy.

The mechanism and “silver effect” in regiodivergent gold-catalyzed hydroamination of terminal alkynyl sulfamides have been explored by the density functional theory (DFT) in the model systems composed of [AuCl(Ph3P)]/AgOTf (series A), AuCl(Ph3P)]/K2CO3 (series B) and [AuCl(Ph3P)]/Ag2CO3 (series C). Our results clearly showed that the regioselectivity of the terminal alkynyl sulfamides is mainly controlled by true involvement of Ag in the catalysis when using different silver salts as a component of gold-based catalytic system, rather than the steric effect. In the [AuCl(Ph3P)]/AgOTf and [AuCl(Ph3P)]/Ag2CO3 catalytic systems, the formation of π-activation or σ-gold-π-silver intermediates turns more favorable the 6-endo-dig cyclization in comparison with the 5-exo-dig pathway. On the other hand, the 5-exo-dig cyclization involving a three-membered Au-C-Au ring activated alkyne intermediate is likely the major pathway for the [AuCl(Ph3P)]/K2CO3 catalytic system. Furthermore, the regioselectivity and its origin as well as the rationalization of “silver effect” are also examined and discussed in detail.

The photoelectrocatalytic CO2 reduction into value-added carbon-based energetic molecules is a promising strategy to store solar energy into chemicals, which lessen the concentration of atmospheric contamination. In this study, the graphitic supported and multiple functionalized nanowire TiO2 semiconductor was firstly used to CO2 reduction with water under photoelectrocatalytic conditions. These photocathodes of R-TiO2@GS were designed to be functionalized by organic ligands that catch CO2 and control the C-C coupling as the Calvin cycle in natural plants. These new organic–inorganic composite electrodes were facile to be prepared and well characterized by using NMR, UV–vis, FTIR, PL, TRPL, EIS and XPS spectra; XRD patterns; SEM, TEM images. The transient absorption spectra of photocathodes demonstrate the efficiency of electron transfer between the Eosin Y and semiconductor, ensuring CO2 reduction. Their Mott–Schottky plots show that the flat band potentials are improved by organic ligands, favoring the ethanol production. The light quantum efficiency of the best photoelectrocatalytic cell of S-TiO2@GS│SCE│Pt reaches to 1.0 % that is 2 times better than natural plant. To better understand the working process of the photoelectrocatalytic cell, a plausible mechanism of CO2 reduction in water was carefully proposed as well.

It is found that hypobromous acid (HOBr) can affect the activity of type IV collagen. Herein, we synthesized a lysosome-targeted fluorescence probe NA-lyso based on Suzuki coupling reaction with naphthalimide as a fluorescent group. HOBr can oxidize the amino group and methylthio group, which increased the degree of conjugation of the probe, thereby affecting its optical properties. Accordingly, it can establish a method for the specific detection of HOBr. NA-lyso has the properties including fast response, high fluorescence quantum yield (Φ = 59.17%), high selectivity, low cytotoxicity and good membrane-permeability. The probe can locate to lysosome of cells. The potential of the probe as biosensor for HOBr was demonstrated by imaging of exogenous and endogenous HOBr in living cells and in mice. In consequence, NA-lyso is expected to be a powerful tool to detect HOBr in complex biosystem and provides a means of exploring physiological functions associated with HOBr in living organisms.

Here a highly efficient cascade approach is reported that combines a cycloaddition reaction with a regioselective strain-release process to afford diverse heterocyclic frameworks through bifunctional catalysis. The cooperation of hydrogen-bonding network activation and a regiodivergent strain-assisted effect is the key to promoting this complex chemical transformation, leading to the generation of two different ring systems in high yields with excellent stereoselectivities. The reaction proceeded by a mechanism involving a "spring-loaded" intermediate with switchable C-C bond cleavages achieved by controllable ring-strain release. This reaction was also amenable to gram scale synthesis with only 0.1 mol % catalyst loading.

Therapy-related side effects and severe antimicrobial resistance still remain an obstacle to Helicobacter pylori eradication. This meta-analysis aimed to investigate the efficacy of Lactobacillus-supplemented triple therapy on H. pylori eradication rates and therapy-related side effects in children. Five studies involving 484 pediatric patients were included in our analysis. The pooled relative risk (RR) for eradication rates in the Lactobacillus group versus the control group was 1.19 [95% confidence interval (CI) 1.07-1.33]. In subgroup analyses based on dose and duration of Lactobacillus supplementation, the pooled RRs for eradication rates were 1.36 (95% CI 1.15-1.60) in the high-dose group, 1.08 (95% CI 0.86-1.35) in the low-dose group, 1.24 (95% CI 1.06-1.46) in the long-term group, and 1.17 (95% CI 0.96-1.44) in the short-term group. With respect to side effects, Lactobacillus supplementation significantly reduced the incidence of diarrhea (RR = 0.30, 95% CI 0.10-0.85).Conclusions: Lactobacillus, as an adjunct to triple therapy, can increase H. pylori eradication rates as well as reduce the incidence of therapy-related diarrhea in children. And a higher dose and a longer duration of supplementation may conduce to the positive impact of Lactobacillus on H. pylori eradication. What is Known: • Probiotics-supplemented triple therapy may be beneficial in improving H. pylori eradication rates and reducing therapy-related side effects in children. However, not all probiotics are beneficial to H. pylori eradication and the pooled outcomes based on different probiotics may be erroneously extrapolated to other ineffective strains. What is New: • Lactobacillus, as an adjunct to triple therapy, can increase H. pylori eradication rates as well as reduce the incidence of therapy-related diarrhea in children.

A detailed theoretical analysis of the mechanism and chemoselectivity for gold(I)-catalyzed reaction of o-(alkynyl)styrene containing an isopropyl and a methyl at the terminal position of the alkene has been reported in this work. Two different counterions (SbF6– and OTs–) were studied as model catalysts. According to our calculation, for SbF6–, the reaction pathway is more prone to direct 1,2-H shifts (isopropyl H) than the elimination and ring expansion pathway. However, an elimination pathway affords the indenyl derivative by forming p-toluenesulfonic acid (HOTs), which may be the main pathway in the presence of OTs–. The chemoselectivity for the title reaction is mainly determined by the electronic effect of the counterion and the substituent rather than the steric effect. In other words, less basic SbF6– mainly provides the charge separation effect rather than assisted proton elimination. However, the more basic OTs– mainly assist proton elimination through the formation of HOTs. In addition to the good agreement with the experimental data, the density functional theory results also provide a significant contribution to the understanding of the reaction mechanism.

Equivalent input admittance model of DFIG wind turbine is built in synchronous reference frame. DFIG electromagnetic transient, PLL dynamics and rotor side controllers including power control and current control are considered in this model. The influence of rotor inductance on stability of DFIG wind turbine connected with weak grid is investigated based on generalized Nyquist criterion (GNC) which proves that the incensement of rotor inductance has a positive impact on system stability. Phase lock loop (PLL) is a critical component in the system, which may propagate the grid voltage perturbations to the control system and has an adverse impact on stability of DFIG wind turbine. Compared with conventional virtual inductance based control strategy, the improved control strategy proposed in this paper take the influence of PLL dynamics into consideration and can improve the system stability efficiently under weak grid condition. The validity of the improved control strategy is verified by theoretical analysis and simulation.

Three novel 2D coordination polymers [Tb2(μ4-L)2(μ-HL)(μ-HCOO)(DEF)]n (Tb-L), [Eu(μ4-L)(L)(H2O)2]n (Eu-L), and [Nd(μ4-L)(L)(H2O)2]n (Nd-L) were assembled from the corresponding lanthanide(III) nitrates and 5 methoxy-(4-benzaldehyde)-1,3-benzenedicarboxylic acid (H2L) as a main multifunctional building block bearing carboxylate and aldehyde functional groups, using H2O/DEF {DEF = N,N-diethylformamide} as a reaction medium. The obtained coordination polymers were isolated as stable microcrystalline solids and fully characterized by elemental analysis, FT-IR spectroscopy, TGA, BET, PXRD, and single-crystal X-ray diffraction methods. Their structures feature intricate 2D metal–organic networks, which were topologically classified as underlying layers with the 4,6L26 (for Tb-L) or sql (for Eu-L and Nd-L) topologies. Besides, a novel series of mesoporous hybrid materials wherein the Tb-L, Eu-L, or Nd-L coordination polymers are covalently grafted into the amine-functionalized SBA-15-NH2 or MCM-41-NH2 matrices (via the formation of Schiff-base groups) was also synthesized and fully characterized. These hybrid materials show high thermal and photoluminescence stability, as well as remarkable chemical resistance to boiling water, and acidic or alkaline medium. Luminescent properties of the parent coordination polymers and derived hybrid materials are investigated in detail, showing that the latter combine the luminescent characteristics (intense green or red emissions and excellent stability) of lanthanide coordination polymers and structural features of ordered mesoporous silica molecular sieves. Moreover, light emitting devices were assembled, by coating the hybrid materials onto the surface of UV-LED bulbs, and showed excellent light emitting properties.

A new series of five lanthanide(III) metal–organic frameworks with a general formula of [Ln3(bcpb)4(μ-HCOO)(μ-H2O)(H2O)2(DEF)]n (1–5) was generated by solvothermal reactions from Ln(NO3)3·6H2O {Ln = Eu (1), Tb (2), Gd (3), Dy (4), and Sm (5)} and 3,5-bis(3-carboxyphenyl)pyridine (H2bcpb) in an aqueous N,N-diethylformamide (DEF) medium. The obtained products were characterized by elemental analysis, FT-IR spectroscopy, thermogravimetric analysis (TGA), and powder and single crystal X-ray diffraction. The latter reveals that all compounds (1–5) are isostructural and feature very intricate 2D metal–organic frameworks. These were topologically analyzed, revealing a very complex hexanodal underlying net that can be simplified further to a binodal 3,5-connected layer with the 3,5L52 topology. Solid-state photoluminescence properties of 1–5 were studied in detail. Compound 1 exhibits a strong red luminescence upon excitation at 338 nm and its lifetime is 532 μs. Compound 2 shows an intense green luminescence upon excitation at 336 and its lifetime is 981 μs. The triplet state (3ππ*) of bcpb2− studied by using the Gd(III) derivative 3 demonstrated that the ligand effectively populates Tb(III) emission (Φ = 70.96%), whereas the corresponding Eu(III) derivative 1 shows a weak luminescence efficiency (Φ = 15.81%) as the triplet state of bcpb2− has a poor match with the 5D0 energy level of Eu(III). A notable feature of 1 is its remarkable sensing ability for Cu2+ ions and 2,4,6-trinitrophenol (TNP). Besides, a series of heterobimetallic Tb-based MOFs, [Tb3(1−x)Eu3x(bcpb)4(μ-HCOO)(μ-H2O)(H2O)2(DEF)]n {x = 0.001, 0.002, 0.003, 0.01, 0.02, 0.03, 0.04, 0.10, 0.15, 0.20} (compounds 2a–2j, respectively), was prepared. The luminescence studies reveal that the simultaneous presence of the characteristic sharp emission bands of Eu3+ and Tb3+ allows the tuning of the photoluminescence colors of such materials by adjusting the doping concentration of the Eu3+ ions.

In this report we present results of theoretical analysis for the reaction mechanism involving a tungsten-germylyne complex with α, β-unsaturated ketones. Three different substituents, namely H, Me and CF3 in α-position of the unsaturated ketones have been selected to account for a variety of experimental observations. The computed results for different unsaturated ketones are in good agreement with experimental evidence and suggest that the formation of the final product can be achieved through steric as well as electronic effects.

WRKY proteins are transcription factors (TFs) that regulate the expression of defense-related genes. The salicylic acid (SA)-inducible Oryza sativa WRKY6 (OsWRKY6) was identified as a positive regulator of Oryza sativa pathogenesis-related 10a (OsPR10a) by transient expression assays. A physical interaction between OsWRKY6 and W-box-like element 1 (WLE1), which positively regulates OsPR10a/probenazole induced protein 1 expression, was verified in vitro. Several pathogenesis-related (PR) genes were constitutively activated, including OsPR10a, and transgenic rice (Oryza sativa) plants overexpressing (ox) OsWRKY6 exhibited enhanced disease resistance to pathogens. By contrast, PR gene induction was compromised in transgenic OsWRKY6-RNAi lines, suggesting that OsWRKY6 is a positive regulator of defense responses. OsWRKY6-ox lines displayed leaf lesions, and increased OsWRKY6 levels caused cell death. Salicylic acid (SA) concentrations were higher in OsWRKY6-ox lines than in wild-type (WT) plants, and transcript levels of Oryza sativa isochorismate synthase 1 (OsICS1), which encodes a major enzyme involved in SA biosynthesis, were higher in OsWRKY6-ox lines than in WT. OsWRKY6 directly bound to the OsICS1 promoter in vivo. This indicates that OsWRKY6 can directly regulate OsICS1 expression and thereby increase SA concentrations. OsWRKY6 autoregulates its own expression. OsWRKY6 protein degradation is possibly regulated by ubiquitination. Our results suggest that OsWRKY6 positively regulates defense responses through activation of OsICS1 expression and OsWRKY6 stabilization.

Considering the refuse and leachate as one whole system, a conventional landfill (CL) was set as a control, transformation of dioctyl phthalate (DOP) in recirculated landfill (RL) and bioreactor landfill (BL) was studied. Results showed that DOP was detected in both leachate and refuse from CL, RL and BL. The initial DOP amount was 0.8 μg g-1 in the landfill refuse. At the day of 310, refuse sedimentation rates were 7.0%, 11.9% and 24.3% in CL, RL and BL, respectively. DOP removal rates were 17.4%, 30.8% and 31.7% in the refuse from CL, RL and BL, respectively. The residual amounts of DOP with significant differences well fitted exponential decay models in CL, RL and BL. DOP biodegradation was accelerated with the operation of leachate recirculation compared to the conventional operation, and it was further promoted with the introduction of methanogenic reactor.

Casting Mg-Li alloy samples were subjected to solid solution treatment with different temperatures and aging with different times, and the corrosion resistance of different samples was investigated by potentiodynamic polarization measurements in 3.5% NaCl solution. The results show that the corrosion resistance of the Mg-Li alloy is improved with increasing solution temperatures and aging times.

The reaction mechanisms of N-heterocylic carbene (NHC)-catalyzed annulation to 3-pyrancarbaldehydes or cyclopentene were theoretically analyzed. Different from what has been reported for normal aldehydes or enals, our calculation results revealed that the intermediate results from the conjugate addition to the central carbon atom of the allene moiety, instead of forming the Breslow intermediate. The next step, 1,4-addition of the chalcone, resulted in the formation of an enolate anion intermediate. Then, intramolecular conjugate addition and elimination of the NHC catalyst afforded the final product. In addition, the computed results showed good agreement with the experimental evidence, suggesting that both the existence of an allene structure and charge distribution play a crucial role in the outcome of chemoselectivity and involvement of operative intermediates in the reaction pathway.

Seven new 2D or 3D coordination polymers based on the flexible and semirigid pyridine-phthalate building block H2pbda (3-(pyridin-3-yloxy)benzene-1,2-dicarboxylic acid), namely 3D [Cd(pbda)]n (1), 3D [Cd3(OH)2(pbda)2]n (2), 3D [Cd(pbda)(4,4′-bpy)]n (3), 3D {[Co(pbda)(4,4′-bpy)]·2H2O}n (4), 2D {[Zn(pbda)(1,4-bib)]·H2O}n (5), 2D {[Cd(pbda)(1,4-bib)]·H2O}n (6), and 3D {[Co(pbda)(4,4′-bibp)]·2H2O}n (7), were prepared by hydrothermal reactions in the presence (optional) of an ancillary ligand selected from 4,4′-bpy (4,4′-bipyridine), 1,4-bib (1,4-bis(imidazol)butane), or 4,4′-bibp (bis(benzimidazol)propane). Compounds 1–7 were fully characterized and their crystal structures were classified from the topological viewpoint, resulting in the following topological networks: gis in 1, crb in 2, ins in 3 and 7, fsc-3,4-C2/c in 4, and sql in 5 and 6. The results revealed that the crystal architectures and the coordination modes of pbda building blocks are influenced by various factors, including the nature of metal cations, the solution pH, the temperature, and the presence of N-donor ancillary ligands. In addition, TGA data show that almost all compounds are thermally stable up to 300 °C. Zn(II) and Cd(II) derivatives are also strong luminescent emitters.

A novel Schiff-base fluorescent sensor (HL) for Al3+ has been synthesized. The addition of Al3+ results in a significant increase of its fluorescent intensity at 420 nm in ethanol, however, other metal ions have almost no influence on the fluorescence. The reason for this phenomenon might be attributed to the formation of a 1 : 1 stoichiometric L–Al complex which inhibits the photo-induced electron transfer (PET) process. More importantly, the proposed binding mode of L–Al(III) is further identified by theoretical calculations.

The degradation and adsorption behavior of dibutyl phthalate (DBP) in methanogenic phase refuse was investigated through laboratory microcosm experiments. The results showed that the half-life of DBP in the sterilized refuse was 5.9 times higher than in unsterilized samples, but that it decreased by 35.8% when dominant bacterial strains were added. Different concentrations of DBP did not have obvious effects on its degradation. The half-lives of DBP were decreased by 53.0%, 37.2% and 20.8% when the refuse moisture increased from 20%, 40% and 60% to 80%, respectively. The pH of refuse was an important factor influencing DBP biodegradation, with the optimal pH being around 7.0. The optimal temperature for DBP degradation in refuse was around 30°C. In addition, the Freundlich model fits the adsorption and desorption isotherm of DBP for refuse with n values that suggest nonlinear adsorption characteristics. The free energy change ΔG value (−23.5 kJ mol −1 ) indicates that the adsorption of DBP on refuse was a physical reaction. Desorption hysteresis was observed in the DBP desorption experiments. Overall, the results indicate that DBP may accumulate in refuse, and that its transformation and bio-availability may be limited under landfill conditions.

Mg-Li alloy samples were subjected to hot rolling with different reduction, and the corrosion resistance of the samples was investigated by potentiodynamic polarization measurements and electrochemical impedance spectroscopy measurements in 3.5% NaCl solution. The results show that the corrosion rate of the Mg-Li alloy first decreases and then increases with increasing rolling reduction.