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The samples of complex perovskite Ba(Mg1/3Ta2/3)O3 (BMT) were synthesized at various sintering temperatures and the X-ray diffraction (XRD) patterns and Raman spectra of the samples were collected. Both the structure refinements using the XRD data and the Raman spectra show that the samples sintered above 1500°C with high pellet relative density (>95%) take almost-perfect B-site-ordered structure; while the samples sintered below 1400°C with low pellet relative density (<70%) take the more disordered structure at B-sites. The vibrational modes of 1:2 ordered BMT were obtained and illustrated by using first-principle calculations. With the assistance of the calculation results, Raman peaks of BMT were assigned as A1g(1) (107 cm−1), A1g(2) (212 cm−1), A1g(3) (433 cm−1), A1g(4) (798 cm−1), and Eg(1) (104 cm−1), Eg(2) (160 cm−1), Eg(3) (264 cm−1), Eg(4) (386 cm−1), Eg(5) (576 cm−1). The highly ordered BMT sample at B-site shows longer phonon lifetime and weaker coupling among phonons than the disordered BMT, which probably are the intrinsic reasons for the highly ordered BMT sample to have the low dielectric loss. [ABSTRACT FROM AUTHOR]

Low halogen content in tested Powder River Basin (PRB) coals and low loss of ignition content (LOl) in PRB-derived fly ash were likely responsible for higher elemental mercury content (averaging about 75%) in the flue gas and also lower mercury capture efficiency by electrostatic precipitator (ESP) and wet-FGD. To develop a cost-effective approach to mercury capture in a full-scale coal-fired utility boiler burning PRB coal, experiments were conducted adding hydrogen bromide (HBr) or simultaneously adding HBr and selected fly ashes in a slipstream reactor (0.152 × 0.152 m) under real flue gas conditions. The residence time of the flue gas inside the reactor was about 1.4s. The average temperature of the slipstream reactor was controlled at about 155 °C. Tests were organized into two phases. In Phase 1, only HBr was added to the slipstream reactor, and in Phase 2, HBr and selected fly ash were added simultaneously. HBr injection was effective (>90%) for mercury oxidation at a low temperature (155 °C) with an HBr addition concentration of about 4 ppm in the flue gas. Additionally, injected HBr enhanced mercury capture by PRB fly ash in the low-temperature range. The mercury capture efficiency, attesting conditions of the slipstream reactor, reached about 50% at an HBr injection concentration of 4 ppm in the flue gas. Compared to only the addition of HBr, simultaneously adding bituminous-derived fly ash in a minimum amount (30 lb/MMacf), together with HBr injection at 4 ppm, could increase mercury capture efficiency by 30%. Injection of lignite-derived fly ash at 30 lb/MMacf could achieve even higher mercury removal efficiency (an additional 35% mercury capture efficiency compared to HBr addition alone). [ABSTRACT FROM AUTHOR]

In an attempt to develop a biofriendly sol−gel route for the rapid formation of biofunctional silica gels, a biopolymer with good biocompatibility was used to assist the gelation of glycol-modified tetraethoxysilane (GMT) in aqueous system without the addition of any organic solvents. It was found that the biopolymer used could act as an effective accelerator for the sol−gel transition of GMT and an increase of its amount could shorten greatly the gelation time. For such a gelation reaction, its apparent activation energy was determined to be 64.9 kJ/mol according to the Arrhenius equation. In particular, the kinetic mechanism for the formation of the silica gel was investigated by using dynamic rheological data and a scaling fractal model. It was revealed that the biopolymer used could change the sol−gel transition mechanism from reaction-limited kinetics to diffusion-limited kinetics. Circular dichroism analyses confirmed the suitability of using the resultant silica gel for the in situ protein encapsulation. [ABSTRACT FROM AUTHOR]

The photoluminescence (PL) of nanocrystal present in porous silicon shifts from the near infrared to the ultraviolet depending on the size when the surface is passivated with Si-H bonds. After oxidation, the centre wavelength of PL band is pinned in a region of 700-750 nm and its intensity increases obviously. Calculation shows that trap electronic states appear in the band gap of a smaller nanocrystal when Si = O bonds or Si-O-Si bonds are formed. The changes in PL intensity and wavelength can be explained by both quantum confinement and trap states in an oxidation layer of nanocrystal. In the theoretical model, the most important factor in the enhancement and the pinning effects of PL emission is the relative position between the level of the trap states and the level of the photoexcitation in the silicon nanocrystal. [ABSTRACT FROM AUTHOR]

Detailed studies of a new approach to the synthesis and encapsulation of silver and silver halide nanoparticles inside shell-cross-linked cylindrical block copolymer polyisoprene-block-polyferrocenyldimethylsilane (Pl-b-PFS) micelles (1) through in situ redox reactions are reported. The cylindrical nanostructures 1 were prepared by the solution self-assembly of the Pl-b-PFS diblock copolymer in the Pl-selective solvent hexane followed by Pt(O)-catalyzed Pl shell-cross-linking hydrosilylation reactions. The partial preoxidation of the swollen PFS core using tris(4-bromophenyl)aminium hexachloroantimonate [p-BrC6H4)3N][SbCl6] (2, Magic Blue) followed by redox reaction between the remaining Fe(II) centers in the PFS core and Ag+ cations led to the formation of silver nanoparticles. High-resolution scanning transmission electron microscopy images of the resulting peapod structures provided a clear indication that the nanoparticles were encapsulated inside the micelles. The composition of the nanoparticles was analyzed by energy-dispersive X-ray spectroscopy (EDX). By combining the evolution of the UV—vis spectra of the reaction mixture and EDX measurements, we surprisingly found that silver halide seed particles were formed through a precipitation reaction at an early stage of the encapsulation process. The size of the silver nanoparticles varied with different amounts of silver ions added to the micelle solution. When 12 was used as the preoxidant, Agl nanoparticles were formed and encapsulated inside the cylinders through the precipitation reaction between iodide anions and silver ions. The packing density of the resulting Agl nanoparticles was increased by an iterative addition method, which utilizes the reversible redox properties of PFS. The small encapsulated Agl nanoparticles were also shown to serve as seeds for the formation of larger Ag nanoparticles when a silver salt was subsequently added. [ABSTRACT FROM AUTHOR]

The article discusses the results of a study which examined the association of tryptophan hydroxylase 1 (TPH1) gene and arylalkylamine N-acetyltransferase polymorphisms with adolescent idiopathic scoliosis (AIS) in Han Chinese patients. It was found that TPH1 polymorphisms were associated with AIS but not with gender and Cobb angle in AIS patients.

Agrobacterium- tumefaciens-mediated transformation of cotton embryogenic calli (EC) was enhanced by choosing appropriate EC and improving efficiency of coculture, selection cultivation, and plant regeneration. After 48-h cocultivation, the number of β-glucuronidase (GUS)-positive calli characterized by yellow, loose, and fine-grained EC was twofold greater than that of gray, brown, and coarse-granule EC. It indicated that efficiency of transient transformation was affected by EC morphology. And transient transformation efficiency was also improved by cocultivation on the medium adding 50 mg l−1 acetosyringone at 19°C for 48 h. Subculturing EC on the selection medium with low cell density was beneficial to production of more kanamycin-resistant (Km-R) calli lines. From an original 0.3-g EC, an average of 20 Km-R calli lines were obtained from a selection dish and the GUS-positive rate of Km-R clones was 81.97%. A large number of normal plants were rapidly regenerated on the differentiation medium with dehydration treatments and the GUS-positive rate of regeneration plants was about 72.60%. Polymerase chain reaction analysis of GUS-positive plantlets revealed a 100% positive detection rate for neomycin phosphotransferase II gene and uidA. Southern blot of transgenic plants regenerated from different Km-R calli lines demonstrated that the target gene, mostly with the low copy number, has been integrated into the cotton genome. [ABSTRACT FROM AUTHOR]

We have examined the working diameter of capillary columns with diameter of 5, 7, 10 and 20 mm. These modified capillary columns were carefully filled with local Taiwan laterite (LTL). The porosity and density of these packed columns was 0.51±0.02 g/g and 1.27±0.05 g/cm3, respectively. The diffusion experiments were then carried out in synthetic groundwater with Cs loading of 0.1mM at room temperature. Experimental results have shown that the diffusion profiles of modified capillary columns fit Fick’s second law very well. This result revealed that the working diameter of a capillary column can be expanded to at least to 20 mm without affecting the validity of the derived diffusion coefficients. Among these columns, the ones with 5 mm diameter show the most consistent results of the derived K d , apparent and effective diffusion coefficients. Although the derived distribution and effective diffusion coefficients slightly decrease as the diameter of these columns increases due to the increase of the solid/liquid ratio. These values are still informative of the Cs diffusion in local Taiwan laterite. Moreover, our results clearly demonstrate the potential of using “modified capillary method” to study the diffusion behaviors of concerned radionuclide because columns with large diameter enable the filling with more versatile geological substances. [ABSTRACT FROM AUTHOR]

Abstract   Agrobacterium tumefaciens-mediated gene transformation caused highly sterile phenotype in T1 transgenic populations of Arabidopsis thaliana. The phenomenon occurred independent of the genes and construct types used for transformation. The occurring frequency is less than 10% and the phenotype is inheritable. Intensive examination elucidated that the sterility is due to indehiscence or delayed dehiscence of the anthers during the flowering stage, resulting from the reduced or disordered endothecial secondary wall thickening of the anthers in the sterile flowers. Exogenous jasmonic acid application cannot rescue the sterile phenotype. Additionally, by using the Escherichia coli uidA gene encoding the β-glucuronidase as a reporter gene, we indicated that the Cauliflower mosaic virus 35S promoter was not constitutively active as expected previously in the reproductive organs of Arabidopsis. These results contribute significantly to the plant community by suggesting that more careful examination and statistical analysis are needed while studying gain-of-function phenotypes of genes, especially for genes that might be involved in reproductive development. [ABSTRACT FROM AUTHOR]

Novel formulas for analyzing the gain characteristics of the phosphate glass erbium-ytterbium (Er3+-Yb3+) co-doped waveguide amplifier (EYCDWA) are derived from the rate equations and the light propagation equations under the uniform dopant and steady-state conditions. In the derivation of these formulas, we have neglected the amplified spontaneous emission (ASE) and have introduced the initial energy transfer efficiency. By using these formulas, the effects of the pump power, signal power, dopant concentration and waveguide length on the gain characteristics of the EYCDWA are analyzed, the comparison is performed between the EYCDWA and the singly erbium-doped waveguide amplifier (EDWA), and some useful results are obtained. [ABSTRACT FROM AUTHOR]

A sample of poly(ferrocenyldimethylsilane)- b-poly(2-vinylpyridine) (PFS 23- b-P2VP 230), with a short PFS block and a P2VP block 10-fold higher in degree of polymerization, forms spherical micelles when dissolved in ethanol. Over time (hours, days, and weeks), these solutions undergo a micelle sphere-to-cylinder transition eventually forming rather stiff, uniform fiber-like micelles with a core width of 10 nm, lengths between 20 and 50 µm, and approximately four polymer molecules per nm length. Here, we report the results of a combination of transmission electron microscopy, wide-angle X-ray scattering (WAXS), as well as static and dynamic laser light scattering measurements to follow the structural evolution. One key observation is the onset of partial aggregation of spherical micelles after an initial induction period (hours), so that the system as it ages consists of mixtures of free spherical micelles, micelle aggregates, and elongated structures with a high aspect ratio. Another important observation is the growth in intensity and sharpness of the WAXS peak characteristic of crystalline PFS domains as the number and uniformity of the cylindrical micelles increases. This formation of crystalline domains is the likely driving force for the structural transformation. [ABSTRACT FROM AUTHOR]

An aggregation growth model of three species A, B and C with the competition between catalyzed birth and catalyzed death is proposed. Irreversible aggregation occurs between any two aggregates of the like species with the constant rate kernels In(n = 1,2,3). Meanwhile, a monomer birth of an A species aggregate of size k occurs under the catalysis of a B species aggregate of size j with the catalyzed birth rate kernel K(k,j) = Kkjv and a monomer death of an A species aggregate of size k occurs under the catalysis of a C species aggregate of size j with the catalyzed death rate kernel L(k,j)=Lkjv, where v is a parameter reflecting the dependence of the catalysis reaction rates of birth and death on the size of catalyst aggregate. The kinetic evolution behaviours of the three species are investigated by the rate equation approach based on the mean-field theory. The form of the aggregate size distribution of A species ak(t) is found to be dependent crucially on the competition between the catalyzed birth and death of A species, as well as the irreversible aggregation processes of the three species: (1) In the v < 0 case, the irreversible aggregation dominates the process, and ak(t) satisfies the conventional scaling form; (2) In the v [?] 0 case, the competition between the catalyzed birth and death dominates the process. When the catalyzed birth controls the process, ak(t) takes the conventional or generalized scaling form. While the catalyzed death controls the process, the scaling description of the aggregate size distribution breaks down completely. [ABSTRACT FROM AUTHOR]

Biocompatible polymeric material with well-defined, interconnected porous structure plays an important role in many biomedical applications, such as tissue engineering, controlled drug release, biochemical sensing, and 3D cell culture for drug discovery. In this study, a novel fabrication process for porous polymer is developed using high intensity focused ultrasound. This acoustic method is solvent-free and capable of creating interconnected porous structures with varying topographical features at designed locations. An experimental study on the selective ultrasonic foaming technique is presented in this paper We investigated the effects of major process variables, including ultrasound power scanning speed, and gas concentration. Both pore size and interconnectivity of the created porous structures were examined. It was found that the pore size could be con- trolled with the scanning speed of the ultrasound insonation and that interconnected porous structures could be obtained using a partial saturation procedure. A concentration-dependent gas diffusion model was developed to predict the gas concentration profiles for partially saturated samples. A cell culture study was conducted to examine cell growth behavior in the fabricated porous structures. [ABSTRACT FROM AUTHOR]

This article shows the existence of positive solutions for a class of p-Laplacian three-point boundary-value problem on time scales. By using several fixed point theorems in cones, we establish conditions for the existence of at least one, two or three positive solutions for the boundary-value problems. Our results are new even for the corresponding differential (핋 = ℝ) and difference equation (핋 = ℝ), and for the general time scales setting. An example is also given to illustrate our results. [ABSTRACT FROM AUTHOR]

In this present work, the kinetic reaction constants including the forward (kf, Cs adsorption onto granite) and backward (kb, Cs desorption from granite) rate constants of Cs on granite were determined by fitting the experimental data from both adsorption and desorption experiments with a pseudo first-order reaction model. In the case of Cs adsorption, both forward and backward rate constants are consistent with one another as Cs loading less than 0.1 mM. In contrast, both forward and backward reaction constants from desorption experiment dramatically increase as the Cs loading increases. Rearrangement of these desorption data by linearization technique, a notable instantaneous desorption process appears, which profoundly influences the determination of the rate constants. Based on our fitting results, the rate constants including both forward and backward reactions determined from Cs adsorption onto granite are much suitable to represent the adsorption behavior, in which the recommended values are of 0.42 and 0.03 h−1, respectively. [ABSTRACT FROM AUTHOR]

This article presents a study regarding the password authentication as a common approach to system security. It discusses that neural networks have been employed for password authentication to overcome the shortcomings of traditional approaches. There is no verification table needed in neural network approaches to password authentication, but encrypted neural network weights are stored within the system. Moreover, the study suggests the use of a Hopfield neural network technique for password authentication.

Abstract  The settlement, early growth and survival of the larval abalone Haliotis discus hannai in response to eight monospecific benthic diatoms were examined in the laboratory. Postlarvae showed active settling and feeding behaviour in all diatom species and in naturally occurring diatoms. Larval settlement rates differed significantly between experimental substrata after 24 h and 48 h. Nitzschia sp. (96.67 %), Hantzschia amphioxys var. leptocephala (95.00 %) and Navicula seminulum (90.00 %) strongly induced larval settlement of H. discus hannai. Postlarvae could feed on benthic diatoms (Nitzschia sp. (786.84 μm ± 2.50 SE and 773.09 μm ± 2.09 SE). Survival of postlarvae was also greatest on Nitzschia sp. (95.33 % ± 1.45 SE). These results indicate the effectiveness of Nitzschia sp., H. amphioxys var. leptocephala, N. seminulum, Rhaphoneis surirella and Navicula corymbosa as single species over natural diatoms in larval settlement and postlarvae growth of H. discus hannai. Thus, Nitzschia sp. has the best potential diet for larval settlement and postlarvae growth of H. discus hannai. H. amphioxys var. leptocephala and N. seminulum can be used as cues to induce larvae settlement, and R. surirella and N. corymbosa can be used as food for growing postlarval. [ABSTRACT FROM AUTHOR]

Retardation factor ( Rf) is the most frequently used indicator to describe the transport of radionuclides through geological substances. In this work, we compare the Rf values determined by four methods including direct experimental data, model fitting curve, integration technique and modeling at two relative concentration ( C/ C 0) 0.5 and 1.0 in a case study of Cs transport through crushed granite. A simple Q-test indicated all Rf values are valid at 96% confidence level. Meanwhile, the T-test demonstrated that the precision of Rf value is 4.21±0.39 at 90% and ±0.45 at 95% confidence level, which is about 9.3% and 10.7% of the average value of the Rf value. An uncertainty window of 10% is recommended in Rf value determination. [ABSTRACT FROM AUTHOR]

The title compound, C14H15ClN4O2+ C2O42-, was obtained as a 1:1 binary ionic compound. Two cations and two anions are connected via ionic N—H⋯O hydrogen bonds to form an annulus with internal dimensions of about 8.5 × 9.5 A°, and these units are connected through O—H⋯O hydrogen bonds to form a two-dimensional porous layer. Weak C—H⋯π and C—Cl⋯π [Cl⋯centroid = 3.575 (2) and 3.598 (2) Å ] interactions, together with strong π-π stacking interactions [centroid-to-centroid distance = 3.429 (3) Å], contribute to the stability of the structure. [ABSTRACT FROM AUTHOR]

The formation of colloidal unmodified (`naked') gold nanoparticles is investigated by irradiation of a precursor solution with X-rays from a synchrotron source. An interesting morphological evolution as a function of exposure time, from cross-linked network-like structure to individual particles, has been discovered. The particle size decreased with the exposure time and was influenced by the ionic strength of the precursor solution. Contrary to γ-ray exposure, an OH radical scavenger was not required for cluster formation. [ABSTRACT FROM AUTHOR]

The fruiting bodies, spores, and lipid from the spores of Ganoderma lucidum have been widely used for medicinal purpose in China. Ergosterol content may be a suitable marker for evaluating the quality of ganoderma spore and ganoderma spore lipid (GSL) products. A gradient reversed-phase high-performance liquid chromatography method was developed for the simultaneous determination of free and esterified ergosterols in G. lucidum. The contents of free and esterified ergosterols in the different parts (the stipe, pileus, tubes, and spores) of G. lucidum and GSL were determined. The results showed that total ergosterol levels in the stipe, pileus, tubes, and spores of G. lucidum were between 0.8 and 1.6 mg/g. The relative abundances of free to esterified ergosterol were different in the different parts of G. lucidum. The spores and the tubes, the hymenophore tissue that contains the spore-producing cells, have a considerably higher percentage of ergosteryl esters (41.9 and 39.7% of total ergosterol) in comparison with the pileus and stipe tissues (3.6 and 6.2%). [ABSTRACT FROM AUTHOR]

To develop biocompatible sol−gel silica matrix for the encapsulation of biomolecules or drugs, a novel water-soluble silica precursor, tetrakis(2-hydroxyethyl)orthosilicates (THEOS), was used in combination with a water-soluble polysaccharide derivative, hydroxypropyl guar gum (HPGG). We found that the introduction of HPGG could trigger and accelerate the sol−gel transition of THEOS in water and induce rapid formation of homogeneous gel matrix without the addition of any organic solvents or catalysts. Moreover, added HPGG macromolecules had a great influence on the network structure and particle dimension in the silica gel matrix, as confirmed by scanning electron microscope (SEM) observation. From the time sweep rheological measurements, it was found that a higher HPGG amount could lead to shorter gelation time for the sol−gel transition. From the strain and frequency sweep rheological experiments, it was found that the resultant silica matrix containing a higher amount of HPGG exhibited a narrower linear viscoelastic region, a higher dynamic muduli, and greater complex viscosity. In particular, the gel strength of the silica matrix could be modulated by the amount of HPGG. By investigating the controlled release of vitamin B12from the sol−gel silica matrixes, a strong dependence of the release profile on the amount of introduced HPGG was observed. In this case, a higher HPGG amount resulted in lower release rate. [ABSTRACT FROM AUTHOR]

A good understanding of the migration of selenite, Se(IV), through deep granitic layers depends on a good understanding of the geochemistry of these layers. Chemical sequential extraction is applied herein to evaluate the ability of granite to adsorb Se(IV) in DW, GW and SW systems. The experimental results indicate that the removal of crystalline Fe oxides reduces the adsorption of Se(IV), suggesting its importance in granite. The normalized concentrations of Se(IV) adsorbed onto crystalline Fe oxides is approximately 0.0301, 0.0330 and 0.0335 mole Se(IV) adsorbed/mole of Fe in DW, GW and SW systems. Kinetic adsorption experiments are conducted to elucidate the results of the chemical sequential extraction. Both the treated and the untreated granite take the same time to reach their equilibrium, suggesting that crystalline Fe oxides dominate the adsorption of Se(IV). Meanwhile, the one-site model suffices to simulate the kinetics of adsorption. [ABSTRACT FROM AUTHOR]

Abstract: Two polysaccharides, GAPS-1 and SAPS-1, were isolated from the gel and the skin of Aloe barbadensis Miller irrigated with sea water for 3.5 years through a combination of anion-exchange column chromatography and repeated gel chromatography and their chemical characterization and antioxidant activities in vitro were investigated. GAPS-1 and SAPS-1 were composed of Man:Glc:Gal in a ratio of 120:2:3 and 296:36:1 with their molecular weight 1.74×105 and 3.97×104 Da, respectively. IR and 13C NMR study of GAPS-1 and SAPS-1 demonstrated that the main skeletons of GAPS-1 was β-(1→4)-D linkaged mannose with acetylation at C-6 and C-3 of manopyranosyl and SAPS-1 was β-(1→4)-D linkaged galactoglucomannan with acetylation at C-6 of pyranosyl. In a concentration-dependent manner, GAPS-1 and SAPS-1 were demonstrated to have strong scavenging activities against superoxide radical, moderate ferrous chelating effect, moderate scavenging activities of hydroxyl radical, moderate reductive power and moderate inhibition of lipid peroxidation. Furthermore, GAPS-1 exhibited moderate scavenging activity of hydrogen peroxide, while SAPS-1 exhibited weak scavenging activity of hydrogen peroxide. GAPS-1 demonstrated more effective antioxidant activities than SAPS-1. The more acetyl group in GAPS-1 molecules probably contributes to the activities. [Copyright &y& Elsevier]

The kinetics of the reaction CO HO2• → CO2•OH was studied using a combination of ab initio electronic structure theory, transition state theory, and master equation modeling. The potential energy surface was examined with the CCSD(T) and CASPT2 methods. The classical energy barriers were found to be about 18 and 19 kcal/mol for CO HO2• addition following the trans and cis paths, respectively. For the cis path, rate constant calculations were carried out with canonical transition state theory. For the trans path, master equation modeling was also employed to examine the pressure dependence. Special attention was paid to the hindered internal rotations of the HOOC•O adduct and transition states. The theoretical analysis shows that the overall rate coefficient is independent of pressure up to 500 atm for temperature ranging from 300 to 2500 K. On the basis of this analysis, we recommend the following rate expression for reaction R1 k(cm3/mol·s) 1.57 × 105T2.18e-9030Tfor 300 ≤ T≤ 2500 K with the uncertainty factor equal to 8, 2, and 1.7 at temperatures of 300, 1000, and 2000 K, respectively. [ABSTRACT FROM AUTHOR]

A new class of metal-containing diblock copolymers, PFS-b-P2VP (PFS poly(ferrocenyldimethylsilane), P2VP poly(2-vinylpyridine)), with a hydrophobic organometallic block and a highly polar hydrophilic organic block were synthesized via 1,1-dimethylsilacyclobutane (DMSB)-mediated sequential anionic polymerization. In the bulk state, PFS-b-P2VP copolymers with a volume fraction of PFS close to 0.20 give a morphology with cylindrical domains of PFS. A remarkable difference in the morphology of PFS-b-P2VP micelles was observed depending on the nature of selective solvent. Simply by using different alcoholic solvents either spherical or cylindrical micelles can be selectively formed from the same copolymer. WAXS experiments indicate that the crystallinity of the core-forming PFS block may be responsible for this difference. [ABSTRACT FROM AUTHOR]

Multifunctional diimidazole, 2,6-bis(imidazol-1-yl)methyl-4-methylphenol (BIP), was crystallized with different dicarboxylic acids, such as oxalic acid (OA), isophthalic acid (IPA), and terephthalic acid (TPA), affording crystals of (BIP2)·(OA2-) (1), (BIP)·(IPA) (2), (BIP)·(TPA) (3), and (BIP)·(TPA)0.5(4). X-ray single-crystal diffraction studies reveal that all four organic crystals contain strong classical hydrogen bonds (such as O−H···N, O−H···O, etc.), which are usually observed in organic cocrystals of carboxylic acids with heterocyclic bases. Besides, weak C−H···O hydrogen bonds and X··· (X , CH) interactions contribute to the formation of three-dimensional (3-D) networks for these crystals. Interesting annulus with internal dimensions of cavity (about 8.5 Å × 9.5 Å) are demonstrated in crystal 1, and these annuluses are connected through O−H···O hydrogen bonds to form a 2-D porous layer. Because of the coexistence of O−H···N and O−H···O hydrogen bonds between BIP and aromatic carboxylic acids, compounds 2and 3exhibit double-chain structures. Interestingly, while the molar ratio of BIP to TPA is 2:1 in crystal 4, an unusual single−double-chain structure is generated, which is obviously different from the double-chain structure of 3. [ABSTRACT FROM AUTHOR]

Abstract??In this paper, we used bond-length equalization, aromatic stabilization energies (ASE) and nucleus-independent chemical shifts (NICS), calculated with (density functional theory) B3LYP levels at the 6-311+G**basis set, to evaluate the aromaticity of a set of 38 five-member planar ?-electron aromatic systems: sila-, aza- and phospha- derivatives and their parent systems. The result revealed statistically significant correlations among the above three criteria, and the order of aromaticity of the whole set was: Aza- derivatives rings?>?Phospha- derivatives rings?>?Sila- derivatives rings?>?Carbon-containing rings; NICS(0.6) and NICS(0.8) had the same results in evaluating the order of aromaticity in our case. [ABSTRACT FROM AUTHOR]

The reaction kinetics for gaseous hydroxyl radicals (OH) with deliquesced sodium chloride particles (NaClaq) were investigated using a novel experimental approach. The technique utilizes the exposure of substrate-deposited aerosol particles to reactive gases followed by chemical analysis of the particles using computer-controlled scanning electron microscopy with energy-dispersive analysis of X-rays (CCSEM/EDX) capability. Experiments were performed at room temperature and atmospheric pressure with deliquesced NaCl particles in the micron size range at 70−80% RH and with OH concentrations in the range of 1 to 7 × 109cm-3. The apparent, pseudo first-order rate constant for the reaction was determined from measurements of changes in the chloride concentration of individual particles upon reaction with OH as a function of the particle loading on the substrate. Quantitative treatment of the data using a model that incorporates both diffusion and reaction kinetics yields a lower limit to the net reaction probability of net≥ 0.1, with an overall uncertainty of a factor of 2. [ABSTRACT FROM AUTHOR]

Ultrasound imaging is an effective aid to the detection of abdominal cystic echinococcosis. Recently, the images produced have provided more information than just a diagnosis. Different cyst morphologies have been classified into types, and such classifications can be considered to represent a natural history of cyst development. Understanding how cyst structures alter with time is crucial to evaluating the effectiveness of different treatment regimes and to understanding natural degeneration of cysts that can occur. However, the developmental events seen in ultrasound need to be matched more closely to immunological and cellular events if we are to have a fuller appreciation of disease progression and regression. At a community level, the relative proportions of cyst types could also provide epidemiological information on disease transmission. [Copyright &y& Elsevier]

Abstract: Six compounds hispidulin-7-glucuronide (1), β-sitosterol (2), conferyl aldehyde (3), 2′-hydroxyl-5′-methyoxybiochanin A (4), and hispidulin-7-O-d-glycoside (5), 6-methoxyluteolin-7-glycoside (6) were isolated from Salvia plebeia and identified by UV, IR, Mass, 1H and 13C NMR spectra. Their antioxidant activities were investigated individually and compared with α-tocopherol by the oxidative stability instrument (OSI) at 40°C. The oils extracted from Styela clava and Ciona intestinalis Linnaeus with supercritical fluid (SCF) CO2 and ethyl acetate, respectively, were used as substance oils, which were rich in polyunsaturated fatty acids (PUFA), especially in the long chain PUFA icosapentaenoic acid (EPA, 20:5n −3) and docosahexaenoic acid (DHA, 22:6n −3). β-Sitosterol, 2′-hydroxyl-5′-methyoxybiochanin A and 6-methoxyluteolin-7-glycoside exhibited strong antioxidant activities, which increased markedly with increasing concentration, and even stronger than α-tocopherol. The results indicate that the components extracted from S. plebeia should preserve the quality of ascidian oil from ascidian oxidative deterioration. [Copyright &y& Elsevier]

Entropy maximization approach has been widely used in transportation planning. It provides theoretical basis for a class of forecast models on traffic demand. In this paper, the concept of entropy from information theory is borrowed to describe inhabitant trip distribution and then a trip distribution model is presented under constraints of typical characteristics based on origin moments. The model is characteristic of generality. The concrete form of the model depends on the order of the highest origin moment which has a great impact on the precision of the model and the labor of parameters calibration. The paper expatiates on this situation and puts forward an iteration method to ascertain the parameters in the model. And then, an entropy method is given to compare the difference of the models for selection. The application of the models and the methods is illustrated via 2001 trip data from the city of Changchun, China. [ABSTRACT FROM AUTHOR]

In recent years the manufacture of and demand for crystals and oscillators in China have been increasing quickly because of the development of industries, communications, science, transportation, and electronic techniques. This paper introduces the manufacture, research, and characteristics of the technical development of crystals and oscillators in the last ten years in China. To meet the demand from industry, science, and other markets, the number of companies that produce and research crystals and oscillators has increased from several to more than 300 in the last 20 years. Manufacturing technology and equipment have also improved. For marketing and technical reasons, more than 75% of the companies manufacture mainly 49 μ, 49 /25, and μm crystals. Now more and more companies plan to build production lines to make cold-weld crystals and other precision crystals, and at least two companies have already built their production lines. Most of the precision crystals are AT-cut but some are SC-cut. Integrated TCXOs and DTCXOs have been made by different companies, and the frequency-temperature stability of them is from ±2 ppm to ±0.5 ppm in a wide temperature range. Specifications of some OCXOs are almost the same as those of foreign OCXOs. The main design techniques in China are experimental. However, in recent years, specially designed software has been developed for oscillator design, and advanced instrumentation and equipment are used. The market situation for crystals and oscillators has increased. [ABSTRACT FROM AUTHOR]

A new class of starch-based hydrogels incorporating acrylamide (AM) and vinyl pyrrolidone (VP) were prepared by ceric ammonium nitrate initiated polymerization in the presence of N,N′-methylene bisacrylamide (MBA). The swelling and diffusion characteristics in water were studied with respect to the effects of reaction variables such as the type and amount of starch, the amounts of AM and VP, as well as MBA concentration. It was found that these reaction variables affected the swelling ratio of the hydrogels and the kinetics parameters of the water sorption process. The water transport mechanism in the swelling starch-based hydrogels was non-Fickian diffusion. [ABSTRACT FROM AUTHOR]

The catalytic activity of 8.8 wt Ni/MgO-AN prepared from alcogel derived MgO was studied for the dry reforming of methane under high pressure (1.5 MPa). The catalyst showed a self-stabilization process during the reaction that lasted for 50 h, in which the catalytic activity decreased with increasing the reaction time on stream (TOS) up to 12 h, and then became stabilized thereafter. The activity decline during the initial 12 h of the reaction was found closely related to an increase in the amount of carbon deposits on the catalyst, which also became stabilized after the catalyst had served the reaction for 12 h. Comprehensive characterizations of the coked catalyst with Temprature programmed hydrogenation (TPH), X-ray photoelectron spectroscopy (XPS) and X-ray diffractometer (XRD) techniques revealed two kinds of carbon deposits (a-carbon andß-carbon) on the used catalyst. Thea-carbon deposits were found to be produced from CH4decomposition while theß-carbon deposits from CO disproportionation. It was revealed that the accumulation ofß-carbon deposits was a key cause for the activity decline and the self-stabilized catalysis during the initial 12 h of the high-pressure reaction. Moreover, it was also observed that an unavoidable sintering of metallic Ni particles from 6.5 to 11 nm, which happened within the very first hour of the reaction, was not directly related to the catalyst stability. [ABSTRACT FROM AUTHOR]

In terms of the similarity between a road network and a circuit network, this paper demonstrates that Kirchhoff’s current and voltage laws observed in the circuit can be employed in the traffic assignment of the road network. Inspired by the more consummate circuit theory, we put forward a new idea and method of traffic assignment. A set of models is formularized by means of multiobjective nonlinear planning theory, and the solutions are found using MATLAB. An example is provided to prove the feasibility of the new traffic assignment model. [ABSTRACT FROM AUTHOR]

Background: White spot syndrome virus (WSSV) is an important pathogen of the penaeid shrimp with high mortalities. In previous reports, Orf427 of WSSV is characterized as one of the three major latency-associated genes of WSSV. Here, we were interested to analyze the promoter of orf427 and its expression during viral pathogenesis. Results: in situ hybridization revealed that orf427 was transcribed in all the infected tissues during viral lytic infection and the translational product can be detected from the infected shrimp. A time-course RT-PCR analysis indicated that transcriptional products of orf427 could only be detected after 6 h post virus inoculation. Furthermore, a baculovirus-mediated promoter analysis indicated that the promoter of orf427 failed to express the EGFP reporter gene in both insect SF9 cells and primary shrimp cells. Conclusion: Our data suggested that latency-related orf427 might not play an important role in activating virus replication from latent phase due to its late transcription during the lytic infection. [ABSTRACT FROM AUTHOR]

Normal adhering cells undergo apoptosis shortly after loss of adhesion to substratum, a phenomenon known as "anoikis." In-vitro-transformed cells and cancer-derived cells are able to survive and grow in the absence of anchorage to the extracellular matrix (ECM) and their neighboring cells. This represents one of the most important oncogenic properties of cancer cells. Integrin-ECM-mediated function is essential for survival and growth of normal adhering cells, while cancer cells are able to abrogate this requirement. This article will review and summarize the recent findings from our laboratory about the molecular signaling pathways important for the regulation of anchorage-independent survival and the growth of transformed fibroblasts and epithelial cells. Our study has shown that integrin-ECM-mediated signaling and cytoskeletal architecture play an essential role in effective recognition of the substrates by activated protein-tyrosine kinases (PTK) and their subsequent signaling functions. Among the various oncogenic PTK-activated pathways, phosphatidylinositol 3-kinase {PI3K)/Akt signaling is the most critical for anchorage-independent survival and growth. The activation of signal transducer and activator of transcription-3 (Slat3) and its function overlap partially with that of the PT3K/Akt in promoting anchorage-independent growth. Among the Rho family guanosine triphosphatases (GTPase), Cdc42, and to some extent Rac1. also appear to be important for promoting anchorage-independent growth. [ABSTRACT FROM AUTHOR]

In this paper, we introduce a novel temperature compensated crystal oscillator—analog memory compensated crystal oscillator (AMCXO), a microcomputer compensated crystal oscillator (MCXO) based on an analogue approach, and we compare the performance between MCXO and AMCXO, and analyze the necessity of developing AMCXO. Both AMCXO and MCXO, combined with their test systems, use computers to generate the control signals used for the compensated crystal oscillators according to temperature variation. However, the execution devices are much different from each other in the practical temperature compensated crystal oscillators. A MCXO uses a set of digital units, including a microprocessor, to realize the compensation. For it, equations or tables are used to express the relationship between the control signal and temperature. An AMCXO uses an analogue memory, which has the same functions as the digital units of MCXO. For AMCXO, a curve or figure based on the equations or tables is used to express the same relationship. Their test systems have obvious distinctions in temperature experiment, data acquisition, and processing. A better performance will be obtained by using a more complicated AMCXO test system, and the cost can be reduced at the same time. [ABSTRACT FROM AUTHOR]

The interactions of styrene and phenylacetylene and their isotope substitutions with a Si(111)7×7 surface have been studied as model systems to mechanistically understand the chemical binding of conjugated π-electron systems to di-radical-like silicon dangling bonds of the adjacent adatom-rest atom pair. Vibrational studies show that styrene mainly binds to the surface through a di-radical reaction involving both the external C=C and its conjugated internal C=C of the phenyl ring with an adjacent adatom-rest atom pair, forming a 5-ethylidene-1,3-cyclohexadiene-like skeleton. On the other hand, phenylacetylene was shown to be covalently attached to Si(111)-7×7 through the external C≡C, forming a styrene-like conjugation system. These experimental results are consistent with density functional theory calculations. The different binding mechanisms for styrene and phenylacetylene clearly demonstrate that reaction channels for multifunctional organic molecules are strongly dependent on the chemical and physical properties of the functional groups. The resulting π-electron conjugation structures may possibly be employed as intermediates for further organic syntheses and fabrication of multilayer organic films on semiconductor surfaces. [ABSTRACT FROM AUTHOR]

Nanosized lanthanum nickel oxide powder LaNiO3 with perovskite structure was successfully synthesized at a relatively low calcination temperature by using an amorphous heteronuclear complex LaNi(DTPA) · 6H2O as a precursor. The precursor decomposed completely into nickel oxide above 600°C based on the DTA and TGA results. XRD demonstrated that nanosized LaNiO3 crystalline powder with pure perovskite structure was obtained after the calcination temperature increased to 700°C. The effects of calcination time and temperature were also examined by XRD and TEM. The results indicated the grain size and the crystal size of LaNiO3 increased with the calcination temperature from 600°C to 900°C, and were less influenced by the heat-treatment time. The electrical resistivity of the powder decreased when the calcination temperature increased. It can be concluded that it is a useful way to synthesize nanosized perovskite oxides using an amorphous complex as a precursor, and this method can be easily quantitatively controlled. [ABSTRACT FROM AUTHOR]

Examines the synthesis of two ferrocene-containing phosphoramidites for electronic detection of nucleic acids. Thermal stability of ferrocene-modified DNA; Use of cyclic voltammetry; Impact of ferrocenyl group of the ribose ring on DNA stability.

Background: Breast cancer is a serious threat to women's health with high morbidity and mortality. The development of more effective therapies for the treatment of breast cancer is strongly warranted. Growing evidence suggests that targeting glucose metabolism may be a promising cancer treatment strategy. We previously identified a new glyceraldehyde-3-phosphate dehydrogenase (GAPDH) inhibitor, DC-5163, which shows great potential in inhibiting tumor growth. Here, we evaluated the anticancer potential of DC-5163 in breast cancer cells. Methods: The effects of DC-5163 on breast cancer cells were investigated in vitro and in vivo. Seahorse, glucose uptake, lactate production, and cellular ATP content assays were performed to examine the impact of DC-5163 on cellular glycolysis. Cell viability, colony-forming ability, cell cycle, and apoptosis were assessed by CCK8 assay, colony formation assay, flow cytometry, and immunoblotting respectively. The anticancer activity of DC-5163 in vivo was evaluated in a mouse breast cancer xenograft model. Results: DC-5163 suppressed aerobic glycolysis and reduced energy supply of breast cancer cells, thereby inhibiting breast cancer cell growth, inducing cell cycle arrest in the G0/G1 phase, and increasing apoptosis. The therapeutic efficacy was assessed using a breast cancer xenograft mouse model. DC-5163 treatment markedly suppressed tumor growth in vivo without inducing evident systemic toxicity. Micro-PET/CT scans revealed a notable reduction in tumor 18F-FDG and 18F-FLT uptake in the DC-5163 treatment group compared to the DMSO control group. Conclusions: Our results suggest that DC-5163 is a promising GAPDH inhibitor for suppressing breast cancer growth without obvious side effects. 18F-FDG and 18F-FLT PET/CT can noninvasively assess the levels of glycolysis and proliferation in tumors following treatment with DC-5163. [ABSTRACT FROM AUTHOR]

Generally, it is very difficult to control the size of large compound vesicles. Here, we introduce a novel method for the preparation of biodegradable large compound vesicles with controlled size and narrow size distribution by using aqueous nanodroplets as templates. [ABSTRACT FROM AUTHOR]

To enhance light absorption in the visible region for the utilization of sunlight, eight mixed-valence polynuclear CuI/CuII clusters have been synthesized for evaluating their photothermal conversion performance. They are fabricated considering the ligand's electron density distribution inhomogeneity using 1,2,3-triazole (3N) or tetrazole (4N) and different mono-phosphine ligands. We report here the synthesis, crystal structure, characterization, optical properties, and photothermal conversion performance of these clusters. X-ray crystal structures reveal that those pentanuclear clusters are neutral clusters with octahedrally- coordinated copper(II) ion being surrounded by four tetrahedrally coordinated copper(I) ions. Interestingly, with the introduction of the mixed-valence centers, these compounds show additional light absorption centers in 350-600 nm via the IVCT transition mechanism, compared with our previously reported Cu(II) compounds. These clusters show excellent photothermal conversion performance, with an average equilibrium temperature (~60 °C) and a temperature increment (~40 °C), which are also superior to Cu(II) complexes (the average equilibrium temperature ~55 °C). This work proves that it is possible to design and prepare new polynuclear mixed-valence CuI/CuII clusters for achieving high-performance photothermal conversion materials. [ABSTRACT FROM AUTHOR]

The relation between the output power and input pump power and then the threshold pump power and slope efficiency of a four-level single mode fiber laser is analysed in terms of the four-level rate equations and the numerical results are in good agreement with the available experimental results by M. Shimizu (1987). Meanwhile, the theoretical model of this paper is simpler and more reasonable than that of Shimizu and is applied to design a single mode fiber laser as well as a single mode fiber amplifier with four-level material. [ABSTRACT FROM AUTHOR]

An increased absorption of regioregular poly(3-hexylthiophene) due to surface plasmons (SPs) has been studied by steady state fluorescence spectra measurements and femtosecond transient absorption (TA) technique. The SPs were excited by periodic Ag grating structures transferred from the photoresist gratings which were fabricated by two-beam laser interference. The steady state fluorescence measurements show a maximum enhanced fluorecence of about 16 times larger arising from the absorption enhancement. Further investigation by TA technique reveals that the yield of the polaron pairs on Ag gratings significantly increase, much bigger than that of the pure sample, which also confirms the enhanced absorption efficiency as resulting from the excited SPs. [ABSTRACT FROM AUTHOR]