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A hologram quantitative structure–activity relationship (HQSAR) and topomer comparative molecular-field analysis (CoMFA) were performed on 51 molecules that belong to the azo dyes to determine their affinities to cellulose fiber. The best HQSAR model was obtained by using atoms. Hydrogen atoms as a fragment distinction and a fragment size of 3–6 showed a leave-one-out cross-validated correlation coefficient ( q 2 LOO ) of 0.849 and a non-cross-validated correlation coefficient ( r 2 ) of 0.927. The best topomer CoMFA model with steric and electrostatic field parameters based on three fragments gave satisfactory results ( q 2 LOO  = 0.821; r 2  = 0.934). External predictions were made on a test set and compared with previously reported models. Topomer CoMFA steric, electrostatic, and HQSAR atomic contribution maps were generated to analyze the structural features of this data set that govern their affinity potency. [ABSTRACT FROM AUTHOR]

In this study, 27 polarimetric parameters were extracted from Radarsat-2 polarimetric synthetic aperture radar (SAR) at each growth stage of the rape crop. The sensitivity to growth parameters such as stem height, leaf area index (LAI), and biomass were investigated as a function of days after sowing. Based on the sensitivity analysis, five empirical regression models were compared to determine the best model for stem height, LAI, and biomass inversion. Of these five models, quadratic models had higher R² values than other models in most cases of growth parameter inversions, but when these results were related to physical scattering mechanisms, the inversion results produced overestimation in the performance of some parameters. By contrast, linear and logarithmic models, which had lower R² values than the quadratic models, had stable performance for growth parameter inversions, particularly in terms of their performance at each growth stage. The best biomass inversion performance was acquired by the volume component of a quadratic model, with an R² value of 0.854 and root mean square error (RMSE) of 109.93 g m-2. The best LAI inversion was also acquired by a quadratic model, but used the radar vegetation index (Cloude), with an R² value of 0.8706 and RMSE of 0.56 m² m-2. Stem height was acquired by scattering angle alpha (α) using a logarithmic model, with an R² of 0.926 value and RMSE of 11.09 cm. The performances of these models were also analysed for biomass estimation at the second growth stage (P2), third growth stage (P3), and fourth growth stage (P4). The results showed that the models built at the P3 stage had better substitutability with the models built during all of the growth stages. From the mapping results, we conclude that a model built at the P3 stage can be used for rape biomass inversion, with 90% of estimation errors being less than 100 g m-2. [ABSTRACT FROM AUTHOR]

By now, many translation quasi-zero stiffness (QZS) mechanisms have been proposed to overcome the restriction between the isolation frequency range and the load bearing capacity of linear isolators. The couplings of rotor systems undertake the functions of transmitting static driving torque and isolating disturbing torque simultaneously, which creates the demand of torsion QZS mechanisms. Hence a QZS coupling is presented in this paper, where a torsion magnetic spring (TMS) composed of two coaxial ring magnet arrangements in repulsive configuration is employed to produce negative torsion stiffness to counteract the positive stiffness of a rubber spring. In this paper, the expressions of magnetic torque and stiffness are given firstly and verified by finite element simulations; and the effect of geometric parameters of the TMS on its stiffness characteristic is analyzed in detail, which contributes to the optimal design of the TMS. Then dynamic analysis of the QZS coupling is performed and the analytical expression of the torque transmissibility is achieved based on the Harmonic Balance Method. Finally, simulation of the torque transmissibility is carried out to reveal how geometric parameters of the TMS affect the isolation performance. [ABSTRACT FROM AUTHOR]

A series of novel N -substituted 3-oxo-1,2,3,4-tetrahydro-quinoxaline-6-carboxy- lic acid derivatives were synthesized and evaluated for their biological activities. Among all synthesized target compounds, 13d exhibited the most potent antiproliferative activity against HeLa, SMMC-7721, K562 cell line (IC 50 = 0.126 μM, 0.071 μM, 0.164 μM, respectively). Furthermore, compound 13d inhibited tubulin polymerization (IC 50 = 3.97 μM), arrested cell cycle at the G2/M phase and induced apoptosis. The binding mode at the colchicine binding site was also probed. These studies provided a new molecular scaffold for the further development of antitumor agents that target tubulin. [ABSTRACT FROM AUTHOR]

Carbohydrates are expected to replace petroleum and to become the base of industrial chemistry. Chirality is one particular area in which carbohydrates have a special potential advantage over petroleum resources. Herein, we report a catalytic approach for the direct production of d-tetroses [i.e., d-(−)-erythrose and d-(+)-erythrulose] from d-hexoses through a fast retro-aldol process at 190 °C that achieves a yield of 46 % and completely retains the chiral centers in the final chiral synthon. The d-tetrose products were further converted into their derivatives, thereby accomplishing transfer of chirality from natural chiral hexoses to high-value-added chiral chemicals. Our results also suggest that the product distribution for the conversion of d-hexoses was determined by their isomerization and epimerization trends that competed with their corresponding retro-aldol condensation processes. [ABSTRACT FROM AUTHOR]

In this work, the alternating multi-layer structured reduced graphene oxide＆polyether sulfone (RGO x &PES y) film is fabricated via a facile thermal pressure process, which has independently aligned packing layers to ensure the conductive network. The electromagnetic interference (EMI) shielding performance of the RGO x ＆PES y film can be adjusted with facility by controlling the layer number of the pure RGO and PES films. At a fixed thickness of 0.35 mm, the shielding performance of the multi-layer structured films increases with the increased layer number of the RGO films. Especially, when the number of RGO film is seven, the RGO 7 &PES 6 film provides an efficient EMI shielding performance of about 45 dB in the whole X-band with a low filler content of 7.39 wt%. Moreover, due to the excellent temperature stability of both RGO and PES, the effective EMI shielding performance can be maintained in the wide temperature range of 298 ∼ 473 K. This study provides a facile method for preparing the RGO-based EMI shielding film materials with excellent high-temperature resistance and ultra-low filler content. • The alternating multi-layer structured RGO x ＆PES y film is fabricated. • At a fixed thickness, the SE value of the prepared multi-layer films increases with the increased number of layers. • The multi-layer films exhibit excellent EMI shielding performance of about 45 dB with a low filler content of 7.39 wt%. • The effective SE value of the multi-layer films can be maintained in the wide temperature range of 298 ∼ 473 K. [ABSTRACT FROM AUTHOR]

Developing alkaline hydrogen evolution reaction catalysts with ultra-low overpotential remains a significant challenge. In this paper, a three-dimensional porous Ru/α-MoC has been developed, which features the dual active sites of α-MoC and Ru. The coexistence of ultrafine Ru nanoparticles and Ru single atoms in Ru/α-MoC system is demonstrated by multiple structural characterizations. The fabricated Ru/α-MoC exhibits excellent alkaline HER activity with a low overpotential 25 mV at 10 mA cm−2, outperforming commercial 20% Pt/C (45 mV), and robust electrocatalytic stability at an industrial-scale current density of 400 mA cm−2. Particularly, the turnover frequency value reaches 39.2 s−1 at the overpotential of 100 mV. Experiments and theory investigations demonstrate the electron redistribution at the interface of α-MoC and Ru. The synergistic effect of dual active sites enables the easy cleavage of H-OH bond and the optimal H adsorption energy simultaneously. This work opens up a feasible way to rationally design high-efficient electrocatalysts with dual active sites for typical multistep reactions. The three-dimensional porous Ru/α-MoC with dual active sites as HER electrocatalyst achieves ultralow overpotential at alkaline media. The excellent activity origin is the synergistic effect of dual active sites that facilitate water dissociation and weaken the H adsorption free energy, resulting in an accelerated reaction kinetics for alkaline hydrogen generation. [Display omitted] • High dispersed Ru species are anchored on α-MoC to construct Ru/α-MoC nanocomposites with dual active sites. • Ru/α-MoC interfaces afford remarkably promoted alkaline HER performance. • The synergistic effect of dual active sites at the interfaces enables the easy cleavage of H-OH bond and the optimal H adsorption energy simultaneously. [ABSTRACT FROM AUTHOR]

Asmart dual-responsive fluorescence probe was designed and synthesized for simultaneous sensing of Cys and viscosity. The desired probe revealed high potency of imaging intracellular Cys and viscosity with selectivity and sensitivity, featured by the sharp contrast fluorescence between red and green. More importantly, the probe was successfully applied to simultaneously monitor the fluctuation of intracellular Cys and cytoplasmic viscosity in monensin- and LPS-induced cells. [Display omitted] • A dual-responsive probe can simultaneously sense Cysteine and viscosity. • The probe revealed high potency of imaging intracellular Cys and viscosity. • The probe was applied to monitor the fluctuation of Cys and viscosity in cells. • The probe was applied to elucidate Cys and viscosity in related diseases. [ABSTRACT FROM AUTHOR]

A series of Zr–Al-MWW zeolites with different Zr state and layer-stacking structure are successfully synthesized via direct grafting zirconocene dichloride onto the external silanols of three kinds of MWW zeolites, i.e. MCM-22 with multilayered structure, ITQ-2 (through layer delaminated route) and OL-MWW (by direct hydrothermal synthesis) with oligolayered structure. The structure, porosity and state of grafted Zr species are distinctly different among the three Zr–Al-MWW zeolites. Zr-OL-MWW possesses the highest content of single Zr atoms with an ideal micro-meso-macro pore system, while Zr-MCM-22 and Zr-ITQ-2 contain two kinds of Zr species (ZrO 2 clusters and single Zr atoms) coexisting in various proportions. The high dispersion of single Zr atoms on OL-MWW can be assigned to the large amount of external silanols of OL-MWW. The as-prepared three bi-functional Zr–Al-MWW zeolites are used for the cascade Meerwein-Ponndorf-Verley (MPV) reduction and etherification (ETH) reaction. Among them, Zr-OL-MWW shows dramatically higher conversion of cinnamaldehyde and yield of 1-cinnamyl 2-propyl ether than Zr-MCM-22 and Zr-ITQ-2, owing to the higher catalytic activity of Lewis acid centers from single Zr atoms, as well as more integrated framework Al sites as Brønsted acid centers with good accessibility. This study offers a simple and efficient strategy to construct Lewis-Brønsted acidic zeolites with exposed heteroatom sites and integrated framework structure, which will provide especial potential in the catalytic conversion of macromolecules. Bi-functional Zr–Al-MWW zeolites, i.e. Zr-MCM-22, Zr-ITQ-2 and Zr-OL-MWW were synthesized by direct grafting of zirconocene dichloride onto the external silanols of three zeolite matrixes, and applied in the Lewis-Brønsted cascade reaction. [Display omitted] • Bi-functional Zr–Al-MWW zeolites were synthesized by a direct grafting strategy. • Zr site state correlated to the matching between the amount of external silanols and the content of grafted Zr species. • Oligolayered MWW nanosheet with abundant external silanols produced more single Zr sites than multilayered MWW zeolite. • The ideal hierarchical porosity, integrated Al sites and exposed singe Zr sites provided superior catalytic performance. [ABSTRACT FROM AUTHOR]

Diffusion limitation in micropores of zeolites leads to a demand for optimization of zeolite morphology and/or porosity. However, tailoring crystallization processes to realize targeted morphology/porosity is a major challenge in zeolite synthesis. On the basis of previous work on the salt-aided, seed-induced route, the template effect of seeds on the formation of micropores, mesopores and even macropores was further explored to selectively achieve desired hierarchical architectures. By carefully investigating the crystallization processes of two typical samples with distinct crystal morphologies, namely, 1) nanocrystallite-oriented self-assembled ZSM-5 zeolite and 2) enriched intracrystal mesoporous ZSM-5 zeolite, a detailed mechanism is proposed to clarify the role of silicalite-1 seeds in the formation of diverse morphologies in a salt-rich heterogeneous system, combined with the transformation of seed-embedded aluminosilicate gel. On the basis of these conclusions, the morphologies/porosities of products were precisely tailored by deliberately adjusting the synthesis parameters (KF/Si, tetrapropylammonium bromide/Si and H2O/Si ratios and type of organic template) to regulate the kinetics of seed dissolution and seed-induced recrystallization. This work may not only provide a practical route to control zeolite crystallization for tailoring crystal morphology, but also expands the knowledge of crystal growth mechanisms in a heterogeneous system. [ABSTRACT FROM AUTHOR]

A clear and deep understanding of zeolite crystallization with the addition of organosilane is desirable for the reasonable design and preparation of hierarchical zeolites. Herein, the effects of different organosilanes on zeolite crystallization were systematically studied. It was found that organosilane plays the role of an inhibitor in the silanization-based zeolite preparation, and this inhibition effect was determined by its participation degree. An organosilane with a high participation degree can result in the prolongation of nucleation and growth periods of zeolite as well as the variation of product properties. More importantly, a dynamic participation pathway of organosilane is proposed, that is, the growth of zeolite is accompanied by the continuous removal of organosilane, leading to an increase of product crystallinity as well as the decrease of mesoporosity. This study gives a new insight into the role that organosilane plays in zeolite crystallization, which will help to direct the rational selection of organosilane and design of crystallization condition for the optimal synthesis of hierarchical zeolites. [ABSTRACT FROM AUTHOR]

Review: 122 refs. [ABSTRACT FROM AUTHOR]

Under natural conditions, wild Artemisiae annie in 36 sampling sites of Three Gorges Reservoir Region were researched. Grey correlation analysis of influencing factors of artemisinin content in A. annie was carried out. Results showed that soil alkali-hydrolyzable N and P were the most significant factors affecting artemisinin content in wild A. annie in Three Gorges Reservoir Region. It could be concluded that artemisinin content in A. annie was mainly affected by the soil nutrient. [ABSTRACT FROM AUTHOR]

A core–shell nanozeolite@enzyme bi-functional catalyst is prepared by using nanozeolite β as acidic core and immobilized Candida antar ctica lipase B (CALB) as enzyme shell for the purpose of dynamic kinetic resolution (DKR), and polydiallyldimethylammonium chloride (PDDA) is used as interlayer to compart core and shell. The activities of core and shell in bi-functional catalyst are modulated to achieve the matching between racemization and kinetic resolution (KR) rates in DKR, i.e., a slow racemization rate on core while a fast KR rate on shell. Nanozeolite β with intermediate SiO 2 /Al 2 O 3 ratio provides proper acid amount for racemization step. A relatively thick layer of PDDA not only improves the activity of CALB by its coverage for surface acidic sites but also limits the accessibility and diffusion of substrate towards the acidic core. The CALB shell with larger immobilized amount and higher enzyme activity offers enhanced driving force of DKR process, leading to higher conversion, selectivity and yield. The preparation and activity modulation of core–shell catalyst provide an ideal method to improve the catalytic performance of bi-functional catalyst. [ABSTRACT FROM AUTHOR]

The objective of this work is To investigate the prevalence, comorbidities, impairment, and treatment-seeking of social anxiety disorder in the Chinese military personnel. Military personnel ( n =11,527) were surveyed from May to August 2007 using a multistage whole cohort probability sampling method. A Chinese version of the World Health Organization Composite International Diagnostic Interview (CIDI) was used for assessment, and a military-related socio-demographic questionnaire was used to describe the prevalence distribution. A unified survey was performed to investigate 11 different social situations. The short-form health survey was used to assess role impairment. The 12-month and lifetime prevalence rates of social anxiety disorder were 3.34% (95% CI: 3.25–3.42%) and 6.22% (95% CI: 6.11–6.32%), respectively. Social anxiety disorder was associated with increased odds of depression, substance abuse, panic attacks/disorder, and generalized anxiety disorder. Childhood foster, female, stressful life events, younger age, and being divorced/widowed increase the incidence of social anxiety disorder. Treatment-seeking was relatively rare. Social anxiety disorder is a common disorder in military personnel in China, and it is a risk factor for subsequent depressive illness, substance abuse and other mental disorder. Early detection and treatment of social anxiety disorder are important because of the low rate of treatment-seeking. [ABSTRACT FROM AUTHOR]

Sowing the seeds: A sub‐micron single‐crystal‐like ZSM‐5 catalyst with enriched intracrystal mesopores is synthesized through a facile organic structure‐directing agent‐free and seed‐induced route. The special crystal structure leads to significantly improved catalytic activity, well‐preserved shape selectivity, and slow deactivation in the isomerization of o‐xylene to p‐xylene. [ABSTRACT FROM AUTHOR]

Highlights: [•] Effect of surface micropores on protein adsorption is studied. [•] Proteins show stronger affinity to porous nanozeolites compared to non-porous ones. [•] Greater conformational change may either enhance or decrease enzyme activity. [•] Recognition of amino acids or secondary structures by pore openings is proposed. [•] Pore opening effect could be altered by changing protein coverage. [ABSTRACT FROM AUTHOR]

Polyreactive antibodies are a major component of the natural antibody repertoire and are capable of binding a variety of structurally unrelated antigens. Many of the properties attributed to natural antibodies, in fact, are turning out to be due to polyreactive antibodies. In humans, each day, billions of cells undergo apoptosis. In the present experiments, we show by ImageStream technology that although polyreactive antibodies do not bind to live T cells they bind to both the plasma membrane and cytoplasm of late apoptotic cells, fix complement, generate the anaphylatoxin C5a and increase by as much as 5 fold complement-mediated phagocytosis by macrophages. Of particular importance, T cells undergoing apoptosis following infection with HIV also bind polyreactive antibodies and are phagocytosed. We conclude that the polyreactive antibodies in the natural antibody repertoire contribute in a major way to the clearance of cells made apoptotic by a variety of natural and infectious processes [ABSTRACT FROM AUTHOR]

Highlights: [•] Nano-crystallite oriented-assembled ZSM-5 zeolite is prepared by seed-induced route. [•] Morphology and external surface are regulated by co-effects of KF, template, and seed. [•] Crystallinity and intrinsic acidity are preserved when decreasing crystallite size. [•] Fine accessibility and high acid strength lead to notable LDPE cracking activity. [•] Fast and low-cost preparation opens a possibility for large-scale production. [ABSTRACT FROM AUTHOR]

Abstract: The combination of bio- and chemocatalysts in one-pot is regarded as a breakthrough both for development of new catalytic concepts and for preparation of high-value chemicals. Zeolite nanocrystals (nanozeolites) have been proved as the most used chemical catalysts and as promising supports for enzyme immobilization. These capabilities of nanozeolites endow them with new possibilities for constructing desired platforms for the combination of bio- and chemocatalysis. In this article, several strategies are proposed to develop a one-pot flow microchannel reactor (MCR) by combining enzyme and chemocatalysis via a nanozeolite assembly approach, and the compatibilities of different types of active centers in various assembly strategies are systematically discussed on the basis of the catalytic results of dynamic kinetic resolution (DKR) of sec-alcohol. By precisely controlling the spatial distribution and the ratio of acidic and enzymatic active sites, as well as the reaction conditions, nanozeolite-modified MCR can achieve fast and highly selective one-pot DKR of sec-alcohol within 30min. [Copyright &y& Elsevier]

Abstract: The platinum-encapsulated zeolitically microcapsular catalyst, associated with the immobilized Candida antartica lipase B (Novozyme®435), is successfully employed in the dynamic kinetic resolution of phenylethylamine. A conversion of 80% and a selectivity of 95% are achieved, and negligible loss of activity is detected even after reaction of 5 runs. It is found that the existence of the silicalite-1 shell not only effectively prevents the deactivation of both enzyme and Pt by isolating them in different regions of reaction system, but also significantly reduces the formation of by-products on the Pt nanoparticles within the protected space of zeolitic microcapsule. Such features of zeolitic shell should further promote the designing of various catalysts for multistep reaction network. [Copyright &y& Elsevier]

Abstract: In this paper, uniform H-β nanozeolite microsphere (β-ZMS) prepared by polymerization-induced colloid aggregation, combined with an immobilized lipase B from Candida antarctica (commercially available Novozym® 435), is applied as a racemization catalyst to the one-pot dynamic kinetic resolution (DKR) of aromatic sec-alcohols. The DKRs of various aromatic sec-alcohols can be carried out with high selectivity and conversion under optimum conditions. Importantly, it is found that, compared to commercial zeolites β (C-β), β-ZMSs display high selectivity for small sec-alcohol molecules because their shorter microporous channels reduce the diffusion time of substrate/product in the three-dimensional framework, and thereby decrease the possibility of secondary reactions. However, the β-ZMSs show a high racemization rate in the DKR of large sec-alcohol molecules, such as racemic 1-(1-naphthyl)-ethanol, thanks to their abundant accessible active sites. This observation will not only benefit the performance of acidic zeolite catalysts in one-pot DKR systems but also provide a new perspective on the application of nanozeolites in catalysis. [Copyright &y& Elsevier]

Abstract: Hierarchical structured ZSM-5 zeolite of c-axis-oriented nanorods has been prepared by a zeolite-seed-assisted hydrothermal synthesis method without any type of mesoscale template. The final product has loose aggregation which consists of rod-like nanocrystals with widths of about 20–30nm, formed by the oriented aggregation model. The nitrogen physisorption suggested that the hierarchical structured ZSM-5 zeolite had higher mesopore volume and external surface area than the sample prepared conventionally. Due to the shortened microporous channel and opening mesopore, the prepared HZSM-5 catalyst presents high catalytic activity and stability for the alkylation of phenol with isopropanol. [ABSTRACT FROM AUTHOR]

Abstract: The preparation and mechanism investigation of mesoporosity and morphology are extremely important in the field of mesoporous materials. By using neutral amines as templates and alcohols as co-solvents, a series of HMS with different morphologies and mesoporosities are obtained. When long alkyl chain surfactant (n ⩾16) and short alkyl chain alcohol (CH3OH and C2H5OH) are employed, the increasing alcohol content induces the morphological transformation from lotus-leaf-like flake, to aggregated flake, potato-like vesicle, sphere, and finally to solid nanoparticle. When using short alkyl chain surfactant (n ⩽14) and long alkyl chain alcohol (C3H7OH), hollow vesicle, cracked sphere, sphere and mesoporous nanoparticle are successively obtained with the increase of alcohol content. Compared with the conventional mesoporous materials, HMS with these special morphologies has a unique regionally distributed dual meso-structure. By systematically analyzing the effects of co-solvent and surfactant, it is found that the morphology of the product is mainly determined by the initial surfactant micelle which can be adjusted by the type and concentration of surfactant and alcohol. Moreover, with progress of reaction, the decrease of surfactant concentration and the increase of silica polymerization degree would induce the mesophase evolution of product from 2D lamella-like to 3D wormholelike meso-structures, leading to the formation of dual meso-structured HMS products. The understanding of these processes is helpful for preparing mesoporous materials with various morphology and meso-structure for catalysis, separation and other application fields. [Copyright &y& Elsevier]

Abstract: Organic species are thought to exert an important effect on the formation of the mineral materials by their electrostatic attraction with the cations of minerals. In this work, a series of polyaspartic acids with different hydroxylation degrees (PAsp-x%OH) have been used as crystal growth modifiers to direct the synthesis of calcium phosphate. The change of x in the PAsp-x%OH can precisely adjust its electrostatic interaction with calcium ions and, thereby, modulate the formation process and property of calcium phosphate, such as morphology, crystallinity, organic component content and calcium-to-phosphate ratio. Two competitive reactions are suggested in this system, that is, the combination of calcium ions to PAsp-x%OH and the precipitation of calcium hydrogen phosphate dihydrate. The trends of these two reactions are determined by variation of x in the PAsp-x%OH: lower value of x tends to involve the former, while the higher tends to latter. It has been found that the mineralization process involving PAsp-15%OH displayed a special point to counterbalance the two competitive reactions, leading to the longest induction time. These findings indicate that how an organic species controls the morphology and the formation dynamics of inorganic crystals in biomineralization by the slight modification of its molecular structure. [Copyright &y& Elsevier]

Abstract: Brain serotonin 1A (5-HT1A) receptors play an important role in mood disorders and can modulate various intracellular signaling mechanisms. We previously reported that systemic administration of either full or partial 5-HT1A agonists increases neuroendocrine responses and that tandospirone, an azapirone partial agonist, can activate (phosphorylate) extracellular signal-regulated kinase (ERK) in the hypothalamic paraventricular nucleus (PVN). In contrast, decreased levels of phosphoERK (pERK) have been reported in hippocampus following in vivo administration of either azapirone or aminotetralin 5-HT1A agonists, such as 8-hydroxy-2-dipropylaminotetralin (8-OH-DPAT). The present study investigated the time-dependent activation of MAP kinase in hypothalamus by (+)8-OH-DPAT to determine the regional differences and receptor specificity of the changes in pERK. Adult male rats received a systemic injection of (+)8-OH-DPAT (200 μg/kg, s.c.). The time-dependent changes in ERK activation were examined in hypothalamic nuclei as well as other brain regions associated with modulation of mood. (+)8-OH-DPAT produced a rapid increase (at 5 min) and transient return (at 15 min) of pERK levels in PVN and medial basal hypothalamus. In contrast, pERK levels in hippocampus were reduced at both 5 and 15 min after (+)8-OH-DPAT. Pretreatment with the 5-HT1A receptor-specific antagonist N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-N-(2-pyridinyl)cyclohexanecarboxamide (WAY100635) completely blocked the (+)8-OH-DPAT-mediated changes in pERK levels in PVN, medial basal hypothalamus, and hippocampus. No significant (+)8-OH-DPAT-induced changes in pERK were observed in dorsal raphe or amygdala. In conclusion, these results demonstrate that 8-OH-DPAT activation of MAP kinase signaling in vivo is a transient and region-specific phenomenon and in rat hypothalamus and hippocampus is mediated by 5-HT1A receptors. [Copyright &y& Elsevier]

Abstract: Fluorination by NH4F solution was used to modify the acidity of alumina. The textural and acidic properties of the parent alumina and modified alumina were studied by N2 adsorption and NH3-TPD. It was disclosed that both surface area and acidity of alumina are enhanced by the treatment with 0.1mol/l NH4F solution, while modification with more concentrated NH4F solutions leads to the decrease in surface area of alumina and thereby weakens its acidity. The catalytic properties of these alumina samples were subsequently investigated in the production of DME. Sample AF1, treated by 0.1mol/l NH4F solution, performed best in both methanol dehydration and the STD process (syngas to dimethyl ether) because of its strongest acidity. [Copyright &y& Elsevier]

Abstract: A series of MCM-22 zeolites were prepared by hydrothermal synthesis and subsequent dealumination by oxalic/citric acid leaching and steaming. The structural and acidic properties of the prepared samples were characterized by methods of XRD, ICP-AES, 27Al MAS NMR, pyridine-adsorbed IR and NH3-TPD. The results indicated that the sample treated by oxalic acid (MCM-22O) has the lowest aluminum content while the samples treated by steam have little change of the aluminum content. Unusually, sample MCM-22O possessed the strongest acidity among the dealuminated samples in spite of its lowest content of aluminum. It may be due to its least content of extraframework aluminum, which may lead to the weakening of acidity. Additionally, the prepared zeolites were mixed with a methanol synthesis catalyst and then applied in the process of syngas to dimethyl ether. Citric acid treated sample performed best with the least generation of byproducts, which have been well related to its structural and acidic properties. [Copyright &y& Elsevier]

Various childhood mood disorders are being treated with serotonin selective reuptake inhibitors (SSRIs) such as fluoxetine (Prozac®), yet limited data are available on their effects on serotonergic systems prior to maturation. This study investigated the effects of chronic fluoxetine treatment on 5-HT2A serotonin receptor-mediated neuroendocrine responses in young male rats. Prepubescent male rats were treated with saline or fluoxetine (10 mg/kg/day, i.p.) for 14 days, a treatment regimen producing maximal changes in postsynaptic 5-HT2A function in adults. Eighteen hours post-treatment, the rats received saline or increasing doses (0.5, 2.0, or 5.0 mg/kg, i.p.) of the 5-HT2 receptor agonist (±)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane HCl ((±)-DOI). Trunk blood was obtained to determine changes in oxytocin, ACTH, corticosterone, and renin responses. Fluoxetine produced a small (∼6%) but significant reduction in body weight gain, but no changes were observed in basal hormone levels. In both saline- and fluoxetine-treated rats, (±)-DOI increased plasma oxytocin levels in a dose-dependent manner. However, the magnitude of the oxytocin responses to all doses of (±)-DOI were markedly attenuated (∼50%) in the fluoxetine-treated rats, indicating a functional reduction in the Emax of 5-HT2A receptor-mediated oxytocin responses. In contrast, fluoxetine did not alter the (±)-DOI-induced increases in plasma ACTH, corticosterone, or renin. These data provide the first demonstration of selective neuroadaptive responses in 5-HT2A serotonin receptor function due to prepubescent treatment with fluoxetine. These data may be clinically relevant with respect to the use of selective serotonin reuptake inhibitors in children and adolescents. Synapse 58:102-109, 2005. © 2005 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Hollow zeolite microcapsules with spherical and various non-spherical shapes were fabricated through a novel strategy involving the crystallization of mesoporous silica (MS) particles. This conversion process was achieved by vapor phase transport treatment of MS particles which were pre-seeded by nanozeolite via the electrostatic assembly technique. The capsule shell was composed of closed packed zeolite crystals growing from the initial seeds by consuming the silica “nutrition” in the internal MS cores. The effects of seed size and seed type on the transformation of MS particles were investigated in detail. More importantly, guest species (e.g. Fe2O3 and Ag nanoparticles) which had been incorporated in the mesopores of the MS particles could be spontaneously encapsulated inside the generated capsules during the MS consumption process, thus, hollow zeolite capsules with functionalized interiors could be easily fabricated. [Copyright &y& Elsevier]

[Display omitted] • A series of 1,2,3,4-4 H -quinoxaline derivatives were synthesized. • The antiproliferative activities of all target compounds were determined. • 11a and 11b showed the most antiproliferative activities up to nanomolar level. • 11a arrest cell cycle in G2/M and induce cell apoptosis in dose-dependent manner. • 11a acted on the colchicine binding site based on the molecular docking study. Colchicine binding site inhibitors (CBSIs) hold great potential for the treatment of various tumors and they can overcome multidrug resistance which the existing tubulin inhibitors such as paclitaxel and vinorelbine are faced with. Herein, we report the design, synthesis and biological evaluation of a series of tetrahydro-quinoxaline derivatives as colchicine binding site inhibitors. All the synthesized compounds were evaluated for their in vitro antiproliferative activities against HT-29 and Hela cancer cell lines, and most of the target compounds demonstrated moderate to strong activities towards two tumor cell lines. In addition, the structure-activity relationships of these derivatives were also discussed. Among them, compounds 11a and 11b showed the most potent activities. Moreover, compound 11a inhibited the tubulin polymerization in both cell-free and cellular assays. Further profiling of compound 11a revealed that it arrested cell cycle in G2/M and induced cell apoptosis in a dose-dependent manner. Furthermore, molecular docking study proved that compound 11a acted on the colchicine binding site. Therefore, 11a is a promising candidate for the discovery of colchicine binding site inhibitors. [ABSTRACT FROM AUTHOR]

An effective and safe route is proposed to prepare supported Mo2C-based catalysts from organic–inorganic hybrids, which exhibit high activity and stability for producing H2from methanol catalytic decomposition. [ABSTRACT FROM AUTHOR]

An effective and safe route is proposed to prepare supported Mo2C-based catalysts from organic–inorganic hybrids, which exhibit high activity and stability for producing H2from methanol catalytic decomposition. [ABSTRACT FROM AUTHOR]

Frontispiece: Co-hydrolysis and Seed-Induced Synthesis of Basic Mesoporous ZSM-5 Zeolites with Enhanced Catalytic Performance Keywords: basic zeolite; Knoevenagel condensation; mesoporous zeolite; non-classical crystallization; seed-induced synthesis EN basic zeolite Knoevenagel condensation mesoporous zeolite non-classical crystallization seed-induced synthesis 1 1 1 05/18/20 20200515 NES 200515 B Basic mesoporous ZSM-5 b with adjustable alkaline-earth metal species has been subtly synthesized with the "meeting" of seed and co-hydrolysis method. Basic zeolite, Knoevenagel condensation, mesoporous zeolite, non-classical crystallization, seed-induced synthesis. [Extracted from the article]

The reaction of diorganotin(IV) with ligands (HL1 = 3-aminopyridine-2-carbaldehyde N(4) methylthiosemicarbazone, HL2 = 3-aminopyridine-2-carbaldehyde N(4)-dimethylthiosemicarbazone) afforded two compounds [PhSn(L1)Cl 2 (1) and [(Ph) 2 Sn(L2)Cl] (2), respectively. The compounds were characterized by elemental analysis, infrared spectrum, UV–vis spectrometry, and X-ray crystallography. The ligands and corresponding complexes were assayed for their in vitro pharmaceutical activity against different pathogenic strains of bacteria by disk diffusion method. The results demonstrate that 1 – 2 have remarkable antibacterial activity against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). 1 exhibit higher antibacterial properties against S. aurenu (MIC = 0.00095 μg/mL) and E. coil (MIC = 0.0019 μg/mL). In the same experimental conditions, the two complexes display more potent activity relative to standard antibiotics Kanamycin and Ampicillin. Image 1 • 1 and 2 were successfully synthesized and characterized. • The compound 1 shows a more efficient antibacterial action than standard antibacterial substances. • The different antibacterial activities of two compounds are due to the changes of the substituents. • The possible antibacterial mechanism of 1 was explored systematically. [ABSTRACT FROM AUTHOR]

In this study, titanium nitride (TiN)/reduced graphene oxide (RGO) composites were prepared via a facile hydrothermal and thermal nitridation process. Due to their favorable electromagnetic wave dissipation ability and appropriate electromagnetic (EM) impedance matching, the TiN/RGO flakes embodies distinct advantage as compared to single component RGO nanosheets and TiN nanoparticles. Moreover, the effective electromagnetic absorption frequency range of the TiN/RGO flakes could be designed by controlling the mass ratio of the precursor. When the mass ratio of nanosized titanic acid to graphene oxide is 1.4:1, the reflection loss of the TiN/RGO with only 2.0 wt% absorber loading reaches −42.85 dB at 8.88 GHz with a thickness of 4.0 mm and a broad effective absorption bandwidth (R L < −10 dB) of 6.7 GHz, which compete well with those observed in several RGO-based composites with much higher filler loadings. The combined excellent EM absorption property with simple production procedure and ultralow absorbent content requirement endow the TiN/RGO flakes as a promising lightweight and efficient EM absorption material suitable for harsh application conditions. • TiN/RGO flakes were prepared via an in-situ hydrothermal and thermal nitridation process. • The TiN/RGO flakes embodies distinct advantage as compared to single component RGO and TiN nanoparticles. • The effective electromagnetic wave dissipation ability and frequency range of TiN/RGO flakes could be rationally tuned. • TiN/RGO flakes could be used as lightweight microwave absorption materials suitable for harsh application conditions. [ABSTRACT FROM AUTHOR]

Background: Drought is a major environmental constraint to plant growth, development and productivity. Compared with most willows that are generally susceptible to drought, the desert willow Salix psammophila has extraordinary adaptation to drought stress. However, its molecular basis of drought tolerance is still largely unknown. Results: During polyethylene glycol 6000 (PEG 6000)-simulated drought stress, we found that the osmotic adjustment substances were accumulated and the antioxidant enzyme activities were enhanced in S. psammophila roots. A total of 8172 differentially expressed genes were identified in roots of S. psammophila through RNA-Sequencing. Based on K-means clustering, their expression patterns were classified into nine clusters, which were enriched in several stress-related processes including transcriptional regulation, response to various stresses, cell death, etc. Moreover, 672 transcription factors from 45 gene families were differentially expressed under drought stress. Furthermore, a weighted gene co-expression network was constructed, and eight genes were identified as hub genes. We demonstrated the function of two hub genes, magnesium-dependent phosphatase 1 (SpMDP1) and SpWRKY33, through overexpression in Arabidopsis thaliana. Overexpression of the two hub genes enhanced the drought tolerance in transgenic plants, suggesting that the identification of candidate drought tolerance genes in this study was highly efficient and credible. Conclusions: Our study analyzed the physiological and molecular responses to drought stress in S. psammophila, and these results contribute to dissect the mechanism of drought tolerance of S. psammophila and facilitate identification of critical genes involved in drought tolerance for willow breeding. [ABSTRACT FROM AUTHOR]

Background: Depression is a chronic illness that generally requires lifelong therapy. Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive technique with few side effects that has been reported to be useful in the treatment of depression. However, no studies to date have evaluated in a randomized controlled trial (RCT) the efficacy of rTMS for maintenance treatment of depression.Methods/design: In this article, we report the design and protocol of a randomized, single-blind, placebo-controlled, parallel-group, multicenter study in China to evaluate the efficacy of rTMS in the prevention of relapse of depressive symptoms. In total, 540 patients, aged 18 to 60 years, diagnosed with depression and experiencing an acute exacerbation of depressive symptoms, will be enrolled. The study will consist of four phases: a screening/tolerability phase of up to 7 days; an open-label, flexible-dose lead-in phase of 8 weeks; an open-label, fixed-dose stabilization phase of 6 weeks; and a single-blind relapse prevention phase of 12 months. During the open-label phase, all patients will be treated with venlafaxine. Remitters with Hamilton Rating Scale for Depression (HAM-D₁₇) score ≤7 will be eligible to enter the single-blind phase and will be randomly assigned to one of three groups: group 1 on active rTMS and venlafaxine; group 2 on sham rTMS and venlafaxine; and group 3 on venlafaxine alone. Efficacy will be evaluated during the study using relapse assessment (time between subject randomization to treatment and the first occurrence of relapse). Secondary outcome measures will include: symptom changes, measured by the HAM-D₁₇; illness severity changes, measured by the Clinical Global Impression of Severity for Depression (CGI-S-DEP); and changes in subject functioning, assessed with the Personal and Social Performance (PSP)scale. Safety will be assessed throughout the study by monitoring of adverse events, clinical laboratory tests, electrocardiography (ECG), and measurements of vital signs (temperature, pulse, and blood pressure) and weight. Suicidality will be assessed by the Columbia Suicide Severity Rating Scale (C-SSRS).Discussion: The result of this trial will assess the efficacy of rTMS in the prevention of relapse of symptoms of depression by determining whether rTMS in combination with an antidepressant is more efficacious than the antidepressant alone for maintenance of the clinical response.Trial Registration: ClinicalTrials.gov, NCT01516931. [ABSTRACT FROM AUTHOR]