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An efficient approach to the synthesis of guaiazulenyl C3-functionalized indoles with excellent regioselectivities via the Brønsted acid catalyzed arylation of 2-indolylmethanols is developed.

Aberrant T helper-2 (Th2) responses play a critical role in the pathogenesis of allergic diseases. The underlying mechanism is to be further investigated. It is reported that soluble CD83 (sCD83) has immune-regulatory effects. This study aims to investigate the role of sCD83 in the regulation of Th2 polarization. Blood samples were collected from pediatric patients with food allergy (FA). The Th2 response was analyzed by pertinent immunological approaches. An FA murine model was developed to test the role of sCD83 in the regulation of FA response. We found that the serum sCD83 levels were lower in FA patients. A negative correlation was detected between serum sCD83 levels and serum Th2 cytokine levels. The presence of sCD83 suppressed Th2 cell differentiation and antigen-specific Th2 cell activation. sCD83 upregulated the T-bet expression and suppressed the GATA3 expression in CD4+ T cells. Administration of sCD83 suppressed experimental FA. Pediatric FA patients have low serum sCD83 levels. Administration of sCD83 can alleviate experimental FA via suppression of aberrant Th2 polarization.

In southern Xinjiang province, northwest China, farmland is undergoing rapid conversion to orchards or agroforestry. This has improved land-use efficiency but has also caused drastic ecological changes in this region. This study investigated the effects of farmland conversion to orchard or agroforestry on soil total organic carbon (TOC) and several soil labile fractions: readily oxidizable carbon (ROC), light fraction organic carbon (LFOC), and dissolved organic carbon (DOC). Soil samples were collected from seven cropping treatments: a monocultured wheat field (Mono), a 5-year-old jujube orchard (5 J), a 5-year-old jujube/wheat alley cropping system (5 JW), a 10-year-old jujube orchard (10 J), a 10-year-old jujube/wheat alley cropping system (10 JW), a 15-year-old jujube orchard (15 J), and a 15-year-old jujube/wheat alley cropping system (15 JW). The results show that the ROC concentrations varied from 0.17 ± 0.09 g/kg to 2.35 ± 0.05 g/kg across all land-use types and soil depths studied. It was higher in the 0–10 cm and 10–20 cm layers of treatment 10 JW than in other treatments and significantly greater than in the Mono treatment. The highest value of DOC was reached at 593.04 mg/kg in the 15 JW treatment at 0–10 cm. Labile organic carbon decreased with increasing depth in all treatments. The proportion of ROC and LFOC to TOC decreased with increasing soil depth. In all treatments, the ratio of DOC to TOC generally decreased initially and then increased again with increasing depth. Correlation analysis showed that ROC, LFOC, and DOC were closely correlated with TOC (p < 0.01). The ROC, LFOC, and DOC concentrations were significantly correlated with each other (p < 0.01). Following conversion of farmland to jujube orchard or agroforestry, the content and activity of soil organic carbon tended to increase due to augmentation of plant residues. Thus, jujube orchards and agroforestry systems are effective methods to restore soil organic carbon.

As lead-containing products, such as lead batteries, are widely used, water pollution problems caused by Pb2+ show a significant threat to the ecosystem and human health. To overcome this serious problem, the modified poly(methyl methacrylate) (PMMA)/chitosan (CS) composites were prepared by adding CS into the PMMA matrix as functional filler and surface modification. The structure, thermal stability, size, morphology and adsorption properties of the modified PMMA/CS composites were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, and inductively coupled plasma optical atomic emission spectrometry. The results indicated that the modified PMMA/CS composites had a uniform size of about 1 μm and showed quite good thermal stability. In addition, the Pb2+ removal of the modified PMMA/CS composite reached up to 98% when the initial Pb2+ concentrations are under 100 mg l−1. The results of the adsorption isotherms indicated that the Langmuir isotherm fits best to the experimental data when compared with the Freundlich isotherm and Temkin isotherm. All these results demonstrate that modified PMMA/CS has a good adsorption property and can be a promising adsorbent for chelating Pb2+.

Polyvinyl alcohol (PVA) filled with different kinds of ZnO whisker was prepared by chemical cross-linking reaction. It was found that the ZnO whiskers dispersed uniformly after being modified by 3-aminopropyltriethoxysilane (APTES). The PVA/tetrapod-shaped ZnO (PVA/tetra-ZnO) composites showed better adsorption performance than other kinds of PVA/ZnO composites. The framework-supported pore-channel structure was beneficial for the transmission and adsorption of heavy metal ions, and the formation of “brush” pore-channel of PVA/tetra-ZnO composites can effectively retain and capture the heavy metal ions. The PVA/tetra-ZnO composites presented well adsorption on Pb(II), Cd(II), and Cr(III) ions than Ni(II) and showed relatively selective removal on Pb(II) and Cr(III) ions. The adsorbed heavy metal ions presented gradient distribution with high content in the out layer and low content in the inner layer. Pb(II) adsorption capacity qe increased gradually with the increase of initial solution concentration and contact time which tended to be stable at 400 mg/L and 800 min. The maximal adsorption capacity qm obtained by nonlinear fitting reached to about 116 mg/g which was very close to the experiment data. Adsorption isotherm results indicated the monolayer adsorption process of the Langmuir model and the adsorption kinetics data fitted well to the pseudo-second-order model. The adsorption process was spontaneous and the high temperature was in favor of adsorption. The adsorption mechanism was explored as the combination of coordination and ion exchange. Besides, the PVA/tetra-ZnO composites exhibited better stress stability, thermo stability, and favorable regeneration than neat PVA.

Chitosan derivatives containing phosphorus ligands were successfully synthesized in three steps. Depending on the degree of substitution, these derivatives present different states, namely colloidal 1 (16.31%) and powdery 1a (92.99%). Based on this, two kinds of diiron model compounds with different morphologies (2 and 2a) were synthesized. The intermediates (1, 1a) and final products (2, 2a) were characterized by SEM (EDX), EA, FT-IR, XRD and TG-DTA. As new multiphase catalysts, 2 and 2a have been applied to photocatalytic reactions. Under optimum conditions ([Ru(bpy)3]Cl2.6H2O, DMF/H2O/TEA, v/v/v = 8/1/1), the turnover numbers were 35 (2) and 24 (2a) for catalysts in an hour of illumination. In addition, a possible photocatalytic mechanism was proposed.

In this paper, the excavator’s dynamic performance is considered together with the study of its trajectory, stress distribution and vibration. Many researchers have focused their study on the kinematics principle while a few others focused their work on dynamic performance, especially the vibration analysis. Previous studies of dynamic performance analysis have ignored the vibration effects. To address these challenges, the rigid-flexible coupling model of the excavator attachment is established and carried out based on virtual prototyping in this study. The dipper handle, the boom and the hoist rope are modeled as a flexible multi-body system for structural strength. The other components are modeled as a rigid multi-body system to catch the dynamic characteristics. The results show that the number of flexible bodies has little effect on the excavation trajectory. The maximum stress determined for the dipper handle and the boom are 96.45 MPa and 212.24 MPa, respectively. The dynamic performance of the excavator is greatly influenced by the clearance and is characterized by two phases: as the clearance decreases, the dynamic response decreases at first and then increases.

Dithizone is known to be very effective for heavy metal ions retention and widely used as developer in detection methods. To explore a novel surface modified polymer microspheres, this paper prepared a novel modified polystyrene (PS-g-D) microspheres by grafting dithizone as the complexing agent and developer on the surface of PS microspheres. The structure of PS-g-D was analyzed by FT-IR, and the formation of dithizone grafted PS microspheres was proved. The thermal stability and surface morphology of PS and modified PS were studied by TGA and SEM. PS-g-D had a uniform diameter of about 1 μm and exhibited a good thermal stability. The Pb2+ removal increased and reached up to 99% with the decrease of initial Pb2+ concentrations. The study of the isotherms model showed that the adsorption between PS-g-D and Pb2+ is consistent with the Langmuir and Temkin adsorption isotherm models. The adsorption kinetics of PS-g-D is described well by the pseudo-second-order model. It can be seen that the modified PS microspheres exhibit a good adsorption property, and has real potential as a novel adsorbent for water treatment industry due to the introduction of dithizone as complexing agent and developer.

This paper (i) investigated how the microstructure, conductivity, and mechanical properties of Cu-7Cr-0.1Ag microcomposites were changed by cold drawing and subsequent heat treatment, and (ii) produced the Cu-7Cr-0.1Ag microcomposite with an optimum combination of strength and conductivity. The figure of merit Z (combining strength and conductivity) of the Cu-7Cr-0.1Ag microcomposite was larger than that of the microcomposite without silver for each heat treatment. The value of Z of the Cu-7Cr-0.1Ag microcomposite was a maximum after heat treatment for 1 h at 600 °C, indicating that this was the optimum intermediate heat treatment. The following combinations of conductivity, strength and ductility (measured as elongation to fracture) were obtained by the Cu-7Cr-0.1Ag microcomposite with η = 8: (i) 77.9% IACS (International Annealed Copper Standard), 920 MPa and 3.1%; (ii) 79.3% IACS, 880 MPa and 3.3%; and (iii) 79.9% IACS, 798 MPa and 3.5%. These values for the Cu-7Cr-0.1Ag microcomposite were larger than those of the Cu-7Cr microcomposite.

To obtain multi-functional β-iPP composites, β-iPP composites are always filled by multiple fillers with α-nucleating ability. To prepare β-iPP/TiO2/MMT composites, TiO2-supported MMT with a β-nucleating surface was prepared through hydrolysis reaction of Tetra-n-butyl titanate and chemical reaction between pimelic acid and calcium ion. X-ray diffraction and scanning electron micrograph confirmed the formation of TiO2 on the surface of MMT. The differential scanning calorimeter and X-ray diffraction illustrated that the β-iPP composites filled by TiO2 and MMT had lower relative β-phase contents than β-iPP. It is observed by polarized optical microscope that addition of TiO2-supported MMT with a β-nucleating surface into iPP can increase the spherulite nuclei density and decrease the spherulite size significantly and obtain the β-iPP/TiO2/MMT composites with high relative β-phase content.

Diiron mimic modified Nano Silica (1) was synthesized in three steps. The intermediate (2, 3) and final product (1) were characterized by SEM (EDX), elemental analysis, FT-IR, XRD, TG-DTA and AAS. The diiron mimic modified Nano Silica (1) could be considered as a new heterogeneous [FeFe]-hydrogenase model. In addition, 1 was applied to a photocatalytic hydrogen production system which made up of photosensitizer ([Ir(ppy)2(bpy)]PF6), electron sacrifice (TEA), proton source (H2O) and solvent (acetonitrile). The turnover number was 324 for surface modified catalyst and 60 for photosensitizer in 5 h of illumination. The study of the recovered catalyst found that most of the catalysts were broken down within 5 h of catalytic reaction.

The continuous discovery and derivatization of members of the closed borane family indicate that boron chemistry is about to embark on a development trajectory similar to that of carbon chemistry. Thus, three-dimensional, aromatic-like icosahedron closo-dodecaborate (denoted as boron cluster or closo-[B12H12]2−), which has the most perfect structure and the most stable physical and chemical properties in the closed borane family, has begun to undertake important missions in the fields of medicine, energetic materials, host–guest chemistry, new energy, environmental treatment, and optoelectronic materials. Closo-[B12H12]2− attracts increasing research attention because of its unique properties including being abundant hydrogen bond acceptors or donors, the unique chaotropic effect, 12 symmetrical modifiable B–H bonds, high ionic conductivity, high calorific value and weak reduction, and electronically adjustable photoelectric conversion. However, there are almost no reviews or books focusing on the progress and future of closo-[B12H12]2−; this is detrimental to the full development of the potential of this functional anion cluster. Accordingly, this review summarizes the progress of closo-[B12H12]2− in detail, aiming to uncover the mystery of closo-[B12H12]2− and arouse the interest of researchers to promote the vigorous development of borane chemistry.

Monomer casting nylon-6-b-polyether amine (MCPA-b-PEA) copolymer were prepared through anionic polymerization which initiated by TDI-PEA macroinitiators with varying PEA molecular chain length. It ...

A green bioreduction method was used to prepare highly efficient supported TiO2 photocatalysts with bimetallic (Au-Ag) nanoparticles at room temperature using Cinnamomum camphora leaf extract as both the protective agent and reducing agent. The resulted Au-Ag/TiO2 exhibits high photocatalytic activity toward the degradation of organic dyes. It was demonstrated that after some of the biomolecules were removed through ionic-liquid extraction and/or calcinations, the Au-Ag/TiO2 photocatalyst exhibits significantly enhanced catalytic performance toward the degradation of methyl orange compared to the pristine untreated catalyst. As a result, 300 mL of 20 mg/mL methyl orange can be fully degraded in 30 min. These can be explained by the sufficient biomolecules could protect the nanoparticles stay in small size, but excess biomolecules played an unfavorable role in hindering the electron transportation during the catalytic reaction. The low-cost preparation, the high activity, together with the good stability and recyclability make this developed Au-Ag/TiO2 a promising photocatalyst toward the degradation of wastewater.

Panel acoustic contribution analysis (PACA) is an advanced engineering tool for noise control and acoustic design in a cabin. In this study, a novel computational method for PACA by using Helmholtz equation least squares (HELS) based on nearfield acoustical holography (NAH) was proposed. According to the new very definition of panel acoustic contribution, formulations of the present method are derived to analyze the relative panel acoustic contributions of each panel in the interior sound field. The significance of this methodology is that it can provide either positive or negative contribution and rank relative acoustic contributions of individual panels to acoustic radiation anywhere in the field based on a single set of the acoustic pressures measured in the near field. A numerical simulation of a scaled vehicle cabin has been investigated to demonstrate the validity of this method. Moreover, the results show the advantage of the proposed method, since it could reflect the contributions of individual panels more correctly than the ranking of acoustic power.

Reversible addition-fragmentation transfer (RAFT) miniemulsion polymerization was one of the prominent controlled/“living” radical polymerization (CLRP) techniques with environmental friendly, energy saving and high efficient characteristics. The well-defined Polystyrene-block-Polystyrene/butadiene-block-Polystyrene (PS-b-PS/Bd-b-PS) triblock copolymers with uniform, tapered or gradient and pure polybutadiene compositions distribution in the middle block were precisely controllably prepared via RAFT seeded miniemulsion polymerization, in which number-average molecular weigh (Mn) t was from 60.00 ~ 82.00 kg/mol with narrow distribution and substantially the similar PS volume fraction about 0.64 ~ 0.65 and 0.80. The copolymers microstructures were characterized by gel permeation chromatography (GPC), fourier translation infrared spectroscopy (FT-IR) and hydrogen nuclear magnetic resonance spectroscopy (1H-NMR). The GPC traces indicated that type curves remained nearly symmetrical, unimodal molecular weight distribution in the whole PS-b-PS/Bd-b-PS triblock copolymers preparation. FT-IR and 1H-NMR results showed that microstructures of the copolymers were mainly 1, 4-trans butadiene with about 10% content of 1, 2-units. Microphase morphology, micromechanical behavior and thermal property of the copolymers were identified by transmission electron microscopy (TEM), tensile testing and differential scanning calorimetry (DSC). The fracture mechanisms of thin layer yielding and cavitation deformation were corresponding to the lamellar and cylindrical morphology in micromechanical behaviors, respectively. It was indicated that microphase morphologies, micromechanical properties and thermal properties were identical to their molecular microstructures, composition profiles distribution, toughening mechanisms and microphase separation strength.

A process for reversible addition-fragmentation chain transfer (RAFT) radical polymerization in a mini-emulsion system stabilized by ammnolyzed poly(styrene-alt- maleic anhydride) copolymer (SMA) as an amphiphilic macro RAFT agent has been applied to the copolymerization of styrene and butadiene to prepare nanoparticles. First, for the RAFT polymerization of styrene, the results of molecular weights (Mns) and polydispersity index (PDIs) determined by GPC showed that the RAFT mini-emulsion polymerization of styrene exhibited good controlled/living nature with a lower degree of aminolysis (∼30%). Second, for the copolymerization of styrene and butadiene, before the gel point the molecular weight growth was followed during the polymerization by GPC and the results revealed that the GPC curve moves to the higher molecular weight indicating the formation of the copolymer. At low conversion, molecular weights (Mns) are in good agreement with theoretical prediction. The microphase separation of the copolymer nan...

The theoretical background for searching for new nonlinear optical (NLO) crystals in borate compounds is briefly reviewed. Several examples are given that clearly show the benefit of the theoretical understanding of the development of new NLO crystals, and the possible routes to next-generation NLO crystals in VUV and IR spectral regions are discussed.

A theoretical study on the stabilities of the crystal structures of K2Al2B2O7 (KABO) and Na2Al2B2O7 (NABO) has been carried out using density functional theory with generalized-gradient corrections. All structures have been optimized by minimizing the total energies with respect to lattice constants and to the atomic coordinates within the unit cell. In the case of KABO, the structure with space group P321 always takes energy advantage over the whole volume range studied, whereas on both volume expansion and contraction, the original NABO structure becomes unstable, taking a structure transition from its P 31c space group to the P321 space group of KABO structure. The theoretical predictions were well realized in the experimental results on the structure changes of the (K1KxNax)2Al2B2O7 solid solution system. q 2005 Elsevier Ltd. All rights reserved.

In the present paper, the crystalline orientation in melt spun (Nd,Dy)-(Fe,Co)-B ribbons was investigated. The average ribbon thicknesses for Nd15Fe77B8 ,N d 15Fe75Co2B8 and Nd14DyFe75Co2B8 at V ¼ 1 m/s are 300, 380 and 420 mm, respectively. The thickness of (Nd,Dy)(Fe,Co)-B ribbons decreases with increasing roller speed. There is a certain roller speed V of about 8 m/s, where c-axis preferential orientation of grains on both roller and free surfaces for Nd15Fe77B8 ribbon is pronounced. Compared with Nd15Fe77B8, the addition of Co improves the caxis orientation of both roller and free surfaces for the Nd15Fe75Co2B8 ribbon at V ¼ 1 m/s. With an increase of roller speed (V < 20 m/s) for Nd15Fe75Co2B8 ribbons, the c-axis orientation behavior enhances for the free surface but reduces for the roller surface. The addition of Dy in Nd15Fe75Co2B8 at V ¼ 5 m/s enhances the c-axis behavior strongly on free surface, but lowers it on roller surface.

Nanocrystalline structure was observed in Fe 79.5 P 12 C 6 Mo 0.5 Cu 0.5 Si 1.5 ribbons after annealed at temperatures from 350 to 500°C. After annealed at 350°C, the ribbon Fe 79.5 P 12 C 6 Mo 0.5 Cu 0.5 Si 1.5 consists of nanoparticles bcc α-Fe(Si, C) and amorphous matrix. Nanoparticles α-Fe(Si, C) and Fe 3 P appear in Fe 79.5 P 12 C 6 Mo 0.5 Cu 0.5 Si 1.5 ribbon after annealed at 500°C. The giant magnetoimpedance effect was found in nanocrystalline Fe 79.5 P 12 C 6 Mo 0.5 Cu 0.5 Si 1.5 ribbons. In the frequency range of 0.1–10 MHz, there is a maximum of magnetoimpedance ratio at 6.9, 1.9, and 1.5 MHz for samples with annealing temperatures of 350, 400, and 450°C, respectively. The value of (Z(0)-Z(65Oe))/Z(0) for the nanocrystalline ribbon Fe 79.5 P 12 C 6 Mo 0.5 Cu 0.5 Si 1.5 with annealing temperature 450°C can reach the value of 13% at 1.5 MHz. The GMI effect in Fe 79.5 P 12 C 6 Mo 0.5 Cu 0.5 Si 1.5 ribbon annealed at 500°C is very small (less than 2%).

Theoretical methods to calculate the optical response of crystals are reviewed. The second-harmonic generation coefficients of borate nonlinear optical crystals are calculated using the anionic group theory combined with the Gaussian'92 ab initio calculation method. Without adjusting the parameters, the calculated values are in good agreement with the experimental values. Meanwhile, a plane-wave pseudopotential total energy package is also used to calculate and discuss the theoretical background and accuracy of the theory. The results indicate that the anionic group theory can predict and calculate the nonlinear optical coefficients of borate crystals reliably, and the energy band calculations can reveal the relationship between nonlinear optical effects and microstructure.

Lymphomatoid papulosis is part of a spectrum of CD30+ cutaneous lymphoproliferative disorders characterized by spontaneous tumor regression. The mechanism(s) of regression is unknown. In a recent study, a selective increase in CD30 ligand expression in regressing lesions of lymphomatoid papulosis and cutaneous CD30+ anaplastic large cell lymphoma was shown, suggesting that activation of the CD30 signaling pathway may be responsible for tumor regression, whereas no difference in Fas/Fas ligand expression was found between regressing and nonregressing lesions. Therefore we tested the effects of CD30 and Fas activation on three CD30+ cutaneous lymphoma cell lines (Mac-1, Mac-2 A, JK) derived from nonregressing tumors of two patients who had progressed from lymphomatoid papulosis to systemic anaplastic large cell lymphoma. To evaluate the effects of CD30 signaling, the cell lines were incubated with a CD30 agonistic antibody, HeFi-1. Proliferative responses, mitogen-activated protein kinase, and nuclear factor kappa B activities were determined with and without CD30 activation. Mac-1 and Mac-2 A showed increased proliferative responses to incubation with CD30 activating antibody, HeFi-1. Inhibition of the mitogen-activated protein kinase activity caused growth inhibition of the Mac-1, Mac-2 A, and JK cell lines. Activation of the Fas pathway induced apoptosis in all three cell lines. Taken together, these findings suggest that resistance to CD30-mediated growth inhibition provides a possible mechanism for escape of cutaneous anaplastic large cell lymphoma from tumor regression. Mitogen-activated protein kinase inhibitors are potential therapeutic agents for the treatment of advanced cutaneous anaplastic large cell lymphoma. J Invest Dermatol 115:1034-1040, 2000

The magnetoimpedance (MI) effect in NiFeMoMn supermalloy ribbon, as well as the magnetoresistance and magnetoreactance, are investigated as the functions of the dc magnetic field and ac driving current frequency. The longitudinal MI reaches 44% in 65 Oe at 0.2 MHz but the transverse effect is small (

In the present paper, the dc longitudinal field and ac frequency dependence of the magnetoimpedance, magnetoresistance, magnetoreactance and magnetoimpedance-phase of NiFeMo permalloy ribbon are investigated. The value of the magnetoimpedance ratio (Z(0) - Z(5172A.m -1 ))/Z(0) of NiFeMo permalloy ribbon can reach 39.54% at 0.3MHz. We also found that the change ratios of the magnetoimpedance (Z(0) - Z(5172A.m -1 ))/Z(0), the magnetoresistance ratio (R(0) - R(5172 A.m -1 )))/R(0) and the magnetoreactance ratio (X(0) - X(5172A.m -1 ))/X(0) intersect at 0.27 MHz where the change ratio of the magnetoimpedance phase (θ(0)-θ(5172A.m -1 ))/θ(0) is zero.

To develop a model for the biology and treatment of CD30+ anaplastic large cell lymphoma (ALCL), we transplanted leukemic tumor cells from a 22-month-old girl with multiple relapsed ALCL. Tumor cells were inoculated intraperitoneally into a 4-week-old SCID/bg mouse and produced a disseminated tumor within 8 weeks; this tumor was serially transplanted by subcutaneous injections to other mice. Morphology, immunohistochemistry, and molecular genetics which demonstrated the NPM-ALK fusion protein, resulting from the t(2;5)(p23;q35), confirmed the identity of the xenograft with the original tumor. The tumor produced transcripts for interleukin-1α, tumor necrosis factor-α, and interferon-γ which could explain the patient's B-symptoms. Treatment of mice with monoclonal antibody (HeFi-1) which activates CD30 antigen administered on day 1 after tumor transplantation prevented tumor growth. Treatment with HeFi-1 after tumors had reached a 0.2 cm 3 volume caused tumor growth arrest and prevention of tumor dissemination. We conclude that transplantation of CD30+ ALCL to SCID/bg mice may provide a valuable model for the study of the biology and design of treatment modalities for CD30+ ALCL.

In the present paper, based on the investigation of the structure and magnetic properties of the compounds RFe11.35Nb0.65Cy (R=Y, Tb, Dy, Ho, Er) and YxDy1−xFe11.35Nb0.65Cy (x=0,0.4,0.6,0.8,1.0) and their parent compounds, a study of the effect of the volume change due to carbonation on the Curie temperature of these compounds has been performed. The d ln TC/d ln V values were derived by comparing the Curie temperature and volume before and after carbonation. Our results indicate that the relationship between d ln TC/d ln V and the Curie temperature TC can be well described in terms of the itinerant-model formalism.