Search

Introduction: Bacterial cellulose (BC) aerogels have received more and more attention due to their renewability, biodegradability and other excellent properties in recent years. Modification of BC aerogels using different methods would expand their applications. However, many problems exist for these modifications, such as a low grafting ratio, the larger dosage of metal catalyst required and so on. Activator regeneration by electron transfer (ARGET) for atom transfer radical polymerization (ATRP) is a novel ATRP method which could significantly reduce the amount of metal catalyst required and achieve a high grafting ratio. Methods: Novel nanostructured BC aerogels containing epoxy groups were prepared by the ARGET ATRP method. BC aerogels were functionalized with initiating sites by reaction with 2-bromoisobutyryl bromide (BiBBr), and followed by ARGET ATRP reaction with glycidyl methacrylate (GMA) which was catalyzed by copper(II) bromide (CuBr2) and N,N,N',N,'N"-pentamethyldiethylenetriamine (PMDETA), and then reduced by vitamin C. BC aerogels containing epoxy groups (BC-g-PGMA) were obtained after freeze-drying. The influence factors of the solvent ratio of N,N-dimethyl formamide (DMF)/toluene, monomer concentration, the concentration of CuBr2, the molar ratio of vitamin C (Vc)/CuBr2,reaction temperature and time on the grafting ratio were investigated. Results: The results showed that the optimal DMF and toluene volume ratio was 2:1, the optimal monomer and CuBr2 concentration were 2 mol/l and 1.5 mmol/l. The optimal molar ratio of PMDETA/CuBr2 and Vc/CuBr2 were 4:1 and 1:1. The optimal reaction temperature and time were 60°C and 9 h. Scanning electron microscopy (SEM) images showed that GMA was strongly adhered onto the surface and inside of the BC pellicle. Conclusions: GMA was self-grown on the BC surface and achieved the high grafting ratio of 1052.7% under optimal conditions. The BC-g-PGMA aerogels containing the epoxy groups will provide wider application prospects in drug release, enzyme fixed, functional materials and other fields. [ABSTRACT FROM AUTHOR]

Aggregation-induced emission (AIE) dyes have recently been intensively explored for biological imaging applications owing to their outstanding optical feature as compared with conventional organic dyes. The AIE-active luminescent silica nanoparticles (LSNPs) are expected to combine the advantages both of silica nanoparticles and AIE-active dyes. Although the AIE-active LSNPs have been prepared previously, surface modification of these AIE-active LSNPs with functional polymers has not been reported thus far. In this work, we reported a rather facile and general strategy for preparation of polymers functionalized AIE-active LSNPs through the surface-initiated atom transfer radical polymerization (ATRP). The AIE-active LSNPs were fabricated via direct encapsulation of AIE-active dye into silica nanoparticles through a non-covalent modified Stöber method. The ATRP initiator was subsequently immobilized onto these AIE-active LSNPs through amidation reaction between 3-aminopropyl-triethoxy-silane and 2-bromoisobutyryl bromide. Finally, the zwitterionic 2-(methacryloyloxy)ethyl phosphorylcholine (MPC) was selected as model monomer and grafted onto MSNs through ATRP. The characterization results suggested that LSNPs can be successfully modified with poly(MPC) through surface-initiated ATRP. The biological evaluation results demonstrated that the final SNPs-AIE-pMPC composites possess low cytotoxicity, desirable optical properties and great potential for biological imaging. Taken together, we demonstrated that AIE-active LSNPs can be fabricated and surface modified with functional polymers to endow novel functions and better performance for biomedical applications. More importantly, this strategy developed in this work could also be extended for fabrication of many other LSNPs polymer composites owing to the good monomer adoptability of ATRP. [ABSTRACT FROM AUTHOR]

Non-rare earth Mn4+-doped oxide matrix phosphors are of increasing interest in the field of light-emitting diodes due to their good spectral properties. Herein, Mn4+-doped Mg 2 ScSbO 6 phosphor was successfully synthesized via the conventional solid-state reaction method. The crystal structure of the sample was determined using a variety of characterization methods such as X-ray powder diffraction and Rietveld refinement analysis. The phosphor has a broadband absorption from near ultraviolet to blue light and emits deep red (∼682 nm) light of 2E g → 4A 2g transition. The photoluminescence intensity and decay lifetime of the Mn4+-doped Mg 2 ScSbO 6 are observed to be strongly dependent on temperature, and the results of quenching analysis were reported. The optimal Mg 2 ScSbO 6 :Mn4+ phosphor has a high color purity of 99.4% with an internal quantum efficiency value of 61.93% modulated by charge compensation of Li+ ions. The photoluminescence peak position of the phosphor can be well matched with the absorption peak of red and far-red phytochrome. Therefore, the deep-red-emitting phosphors have tremendous application merits and potential markets in plant growth. • Mn4+ doped Mg 2 ScSbO 6 phosphors presented deep-red emission. • The internal quantum efficiency of the optimal sample is 61.93%. • The deep-red emission is beneficial for plant growth. [ABSTRACT FROM AUTHOR]

In this paper, the health monitoring of Al 7075 friction stir welded structure was carried out, including elastic and plastic deformation during stretching and bending. A thin film sensor composed of MXene and single-walled carbon nanotubes was developed by simple mixing and vacuum filtration. This flexible MXene/SWCNT thin film sensor combining the sensitivity of MXene with the stability of carbon nanotubes and can be pasted on the surface of Al 7075 FSW joints through polyimide encapsulation to achieve structural health monitoring. The experimental results show that the MXene/SWCNT sensors encapsulated in polyimide can effectively capture the micro strain of different areas during stretching and bending. When the strain of the welded structure is less than 3000, only elastic deformation occurs in different regions of the welded structure, and the sensors located in different regions show the same resistance change rate. When the strain is greater than 3000, the resistance change rate of the sensors in the thermal-mechanical affected zone and heat affected zone obviously, and when the external force is released, there is residual resistance, which proves that the plastic deformation occurs in the welded structure at this time. By comparing the resistance change rate of the sensors in different regions, it can be inferred whether plastic deformation occurs. As the strain further increases, the resistance change rate of the sensor further increases and make a stable response until the structure breaks. This sensor can be used to track the whole process monitoring of welded structure before fracture. [Display omitted] • Thin film sensors composed of SWCNT and MXene were prepared by vacuum filtration. • The MXene/SWCNT sensor can monitor different strain with different aera of welding structure in real-time. • The MXene/SWCNT sensor adopted by polyimide package has good sensitivity and synchronization to cyclic load. • The MXene/SWCNT sensor can be used to follow the entire strain of welding structure till end-of-life. [ABSTRACT FROM AUTHOR]

In order to clarify the asymmetric basal texture effects on the stretchability and the microstructure variations of magnesium alloy sheet, two kinds of stretch forming samples were extracted along the rolling direction (RD) and the transverse direction (TD) from ZK60 magnesium alloy sheet with asymmetric basal texture. Their variations involving the microstructure and the stretch formability were investigated using a visco-plastic self-consistent model, along with the three-dimensional finite element method. The experimental and simulated results together showed that the plastic deformation during stretch forming was concentrated in the central region of the stretch sample. Such plastic deformation was more easily propagated into the surrounding area in the TD sample, making its stretch formability higher by nearly 50.7 % than the RD sample. This was attributed to the weak basal texture in the TD sample which activated more basal slip and tension twinning and consequently increased its hardenability. Additionally, with the variation of the stretch forming behavior, the activation of basal slip narrowed the spread angle of the basal pole for the TD sample, while only increased the basal texture intensity for the RD sample. Moreover, activation of the prismatic slip rotated the <10−10> crystal direction toward the major strain direction (LD), promoting the development of <10−10>//LD-type texture in both samples. These results indicated that the comprehensive stretchability improvement of magnesium alloy sheet required weakening the basal texture symmetrically instead of asymmetrically. • The stretch plastic deformation was concentrated in the central region of stretch sample. • The stretchability of the sample with weak basal texture direction was higher by 50.7 %. • Different stretch behaviors arose from the different contributions of each deformation mode. • Weakening the basal texture symmetrically could improve the stretchability comprehensively. [ABSTRACT FROM AUTHOR]

Gene expression is perturbated by drugs to different extent. Analyzing genes whose expression is frequently regulated by drugs would be useful for the screening of candidate therapeutic targets and genes implicated in side effect. Here, we obtained the differential expression number (DEN) for genes profiled in Affymetrix microarrays from the Connectivity Map project, and conducted systemic comparative computational analysis between high DEN genes and other genes. Results indicated that genes with higher down-/up-regulation number (down_h/up_h) tended to be clustered in genome, and have lower homologous gene number, higher SNP density and more disease-related SNP. Down_h and up_h were significantly enriched in cancer related pathways, while genes with lower down-/up-regulation number (down_l/up_l) were mainly involved in the development of nervous system diseases. Besides, up_h had lower interaction network degree, later developmental stage to express, higher tissue expression specificity than up_l, while down_h showed reversed tendency in comparison with down_l. Together, our analysis suggests that genes frequently regulated by drugs are more likely to be associated with disease-related functions, but the extensive activation of conserved and widely expressed genes by drugs is disfavored. [ABSTRACT FROM AUTHOR]

In order to reduce the feed rate fluctuation of interpolation, a novel approach for NURBS interpolation with minimal feed rate fluctuation based on improved Adams-Moulton (IAM) method is proposed. At first, the representation and calculation of NURBS curve interpolation are described. Then, the constraints of feeding step length are firstly given out to calculate the minimal hoping feeding step length and the detailed IAM method of NURBS curve interpolation is presented. Finally, simulations and experiments are carried out to verify the feasibility and applicability of proposed IAM method. [ABSTRACT FROM AUTHOR]

The mechanical properties of a fused deposition modeling (FDM) process product are greatly influenced by many process parameters. The identified parameters namely deposition orientation, layer thickness and deposition style, raster width, and raster gap are more significant factors contributing to the strength of a FDM product. In this paper, tensile strength, flexural strength, and impact strength are considered as three evaluation indexes to characterize the mechanical properties of a FDM part. An experimental research approach based on the Taguchi method was presented and some special specimens were designed. The influences of the five parameters on the three evaluation indexes were analyzed by the use of analysis of variance (ANOVA). Finally, based on the gray relational analysis, a set of optimal process parameter combination was obtained to optimize comprehensive mechanical properties of FDM parts. [ABSTRACT FROM AUTHOR]

Quantification of multiscale heterogeneity is the key to the simulation of gas-solid two-phase flow. The energy-minimization multiscale (EMMS) model can be used at different scales to describe local and global heterogeneities as well as steady-state fluid dynamics of gas-solid fluidization. However, the same cluster diameter correlation based on energy dissipation was used in all cases, which may give a smaller cluster diameter than single particle diameter at low solids fluxes. In this paper, a description of the solids mass transfer between the dilute and dense phases in heterogeneous gas-solid flow is proposed to replace the correlation of cluster diameter to avoid some problems associated with the empirical calculation of the cluster diameter. This cluster description can facilitate the prediction of the drag coefficient at the scale of numerical cells in computational fluid dynamics (CFD) at extremely low solids fluxes and the radial heterogeneity in large-scale circulating fluidized bed (CFB) risers with downward particle velocities near the wall. It is integrated with two-fluid model (TFM) to simulate the fluid dynamics in an industrial-scale CFB riser accurately, which is also accelerated significantly by using the predicted radial voidage distribution as the initial condition of CFD. [ABSTRACT FROM AUTHOR]

The aim of this study is to evaluate the effects of two different charged amino acids in collagen chains, lysine and glutamic acid, on the fibrillogenesis process of collagen molecules. The turbidity, zeta potential, and fiber diameter analysis suggest that introducing the positively charged lysine into collagen might improve the sizes or amounts of the self-assembled collagen fibrils significantly. Conversely, the negatively charged glutamic acid might restrict the self-assembly of collagen building blocks into a higher order structure. Meanwhile, the optimal fibrillogenesis condition is achieved when the concentration of lysine reaches to 1 mM. Both scanning electron microscopy (SEM) and atomic force microscope (AFM) analysis indicates that compared to pure collagen fibrils, the reconstructed collagen-lysine co-fibrils exhibit a higher degree of inter-fiber entanglements with more straight and longer fibrils. Noted that the specific D-period patterns of the reconstructed collagen fibrils could be clearly discernible and the width of D-banding increases steadily after introducing lysine. Besides, the kinetic and thermodynamic collagen self-assembly analysis confirms that the rate constants of both the first and second assembly phase decrease after introducing lysine, and lysine could promote the process of collagen fibrillogenesis obeying the laws of thermodynamics. [ABSTRACT FROM AUTHOR]

Gas penetrating flow was found to exist in a static cluster model and contribute much to the suspension of particles in our previous study. This phenomenon however needs to be clarified further since particle clusters in actual gas–solid flow have no fixed shapes and internal structures due to their dynamic evolution with time and space. In this article, a general guideline based on gradient calculation is proposed to identify particle clusters from solids concentration fields, so as to quantify gas penetrating flow through dynamic particle clusters. By EMMS-based CFD simulation and two-phase PIV measurement, the internal two-phase flow fields of dynamic particle clusters are analyzed to gain an insight into gas–solid interaction inside particle clusters. Both the simulated and experimental results are qualitatively consistent with the previous findings that gas penetrating flow significantly increases with the increase of cluster voidage and hence should be taken into account in the mathematical modeling of particle clusters in gas–solid fluidization. [ABSTRACT FROM AUTHOR]

A series of organic small molecules were synthesized using Sonagashira coupling reaction, which was post-functionally modified. The UV-VIS-NIR spectra showed that different click reagents can cause different degrees of redshift of the products, and the wide wave absorption can be achieved by using them together. Electrochemical studies show that the introduced click reagents increase the degree of conjugation, causing a reduction in energy bandwidth. Z-scan tests show that after the click, there is a mutual transition between saturable and anti-saturable absorption, which has different modulating effects on the nonlinear absorption of the material, which provides a good idea for the design of optical limiting molecular. [Display omitted] [ABSTRACT FROM AUTHOR]

The effect of nitrogen content (0.001 wt%, 0.009 wt%, 0.017 wt%) on the microstructure, mechanical properties and deformation behaviors of a medium-carbon ferritic-pearlitic steel is investigated in this study. The addition of nitrogen is shown to have little effect on the ferrite-pearlite microstructure and only marginally coarsens it because austenite grain growth is promoted. Although nitrogen is a strong element for solid solution strengthening, nitrogen addition only marginally improves the strength of the steel and has little effect on the ductility because fine Fe 3 N phases are precipitated during the tensile process. The toughness of the steel is markedly decreased by the addition of nitrogen because the dislocation locking effect caused by interstitial nitrogen atoms is enhanced. When the nitrogen content increases from 0.001 wt% to 0.017 wt%, the yield-point phenomenon in the tensile process is first strengthened and then weakened. The yield-point phenomenon is closely related to the dislocation behaviors in proeutectoid ferrite, and the different yield-point phenomena under different nitrogen contents are related to the dislocation locking effect caused by interstitial nitrogen atoms and to the dislocation pinning effect caused by Fe 3 N phases. [ABSTRACT FROM AUTHOR]

A series of symmetric and asymmetric charge-transfer azobenzene complexes are synthesized by Sonogashira coupling reaction, and olefin-alkyne click chemistry without by-products. The click products with adjustable energy levels of the frontier orbitals are tested by NMR, IR, and MS, which have good solubility and are easy to synthesize through the introduction of TCNE, TCNQ, F4-TCNQ. Both UV-VIS-NIR spectroscopy and electrochemical studies are carried out and the cyclic voltammogram has a good correlation with spectroscopy. As a side group, the click part has a positive impact on the material. The nonlinear phenomenon of azobenzene derivatives is experimentally represented by Z-scan technology on 532 nm, and each compound exhibits the expected nonlinear optical properties. • The synthesis route is simple, without side reactions, the reaction is efficient and fast, and the economy is reasonable. • By adjusting the type and number of click reagents, the position of the maximum UV absorption peak of the material can be adjusted to cause a red shift, with different click reagents resulting in different degrees of red shift, thus achieving broad-wave absorption over a wide wavelength band. • The introduction of click reagents makes the materials undergo interconversion between saturable absorption to anti-saturable absorption, which makes it easier to regulate the material properties. [ABSTRACT FROM AUTHOR]

Characterization, digital twins, machine learning, simulation Bridging Multiscale Characterization Technologies and Digital Modeling to Evaluate Lithium Battery Full Lifecycle (Adv. Keywords: characterization; digital twins; machine learning; simulation EN characterization digital twins machine learning simulation 1 1 1 09/05/22 20220901 NES 220901 B Lithium Batteries b In article number 2200889, Kai Yang, Shichun Yang and co-workers demonstrate the potential of cyber hierarchy and interactional network framework (CHAIN) to bridge multi-scale characterization and modeling technologies to evaluate lithium battery overall lifecycle. [Extracted from the article]

• A Pareto optimization model based on estimation of distribution algorithm is designed. • A probabilistic model is constructed to predict position relationships between jobs. • Two neighbourhood operators with modified insertion technique are proposed. This study investigates the impact of production scheduling decisions aims at improving productive and energy-efficient performances simultaneously in distributed blocking flowshops (EDBFSP). To reach a compromise between the conflicting objectives, a Pareto multi-objective optimization model based on the estimation of distribution algorithm (MOEDA) is proposed. Firstly, an initialization method based on the problem-specific characteristics is designed to create a promising population with quality and diversity; secondly, a probabilistic model based on a Bayesian network is constructed to predict position relationships between jobs. Two neighborhood operators with modified insertion technique are proposed to realize the adjustments of both job sequence and processing speed; thirdly, two operators are developed to execute multi-objective local searches on the elite solutions. Aiming at efficient utilization of the resulted blocking and idle time, an energy-saving method is designed for EDBFSP. In the experimental parts, to gain the best performance, the key parameters of MOEDA have been calibrated. The validation is conducted to assess the performances of the designed initialization method, neighborhood search, local search, and energy-saving strategies. The proposed MOEDA is also compared with mainstream metaheuristics for solving green scheduling problems. The experiment results show that the optimization and search ability of MOEDA have gained prominent advantages over other metaheuristics in both precision and distributivity. [ABSTRACT FROM AUTHOR]

The objective of this study was to extract and characterize an advanced collagen aggregate (Ag-col) from porcine acellular dermal matrix (pADM). Based on histological examination, scanning electron microscopy (SEM) and atomic force microscope (AFM), Ag-col was composed of the D-periodic cross-striated collagen fibrils and thick collagen fiber bundles with uneven diameters and non-orientated arrangement. Fourier transform infrared (FTIR) spectra of pADM, Ag-col and Col were similar and revealed the presence of the triple helix. Circular dichroism (CD) analysis exhibited a slightly higher content of α-helix but inappreciably less amount of random coil structure in Ag-col compared to Col. Moreover, imino acid contents of pADM, Ag-col and Col were 222.43, 218.30 and 190.01 residues/1000 residues, respectively. From zeta potential analysis, a net charge of zero was found at pH 6.45 and 6.11 for Ag-col and Col, respectively. Differential scanning calorimetry (DSC) study suggested that the T d of Ag-col was 20 °C higher than that of Col as expected, and dynamic mechanical analysis (DMA) indicated that Ag-col possessed a higher storage modulus but similar loss factor compared to Col. Therefore, the collagen aggregate from pADM could serve as a better alternative source of collagens for further applications in food and biological industries. [ABSTRACT FROM AUTHOR]

In this work, we have conducted a blend of type I collagen and dencichine under acid conditions, followed by investigating the intermolecular interactions between the two components. Fourier transform infrared spectroscopy (FTIR), molecular modeling methods, the circular dichrorism (CD) measurement, and X-ray photoelectron spectroscopy (XPS) studies inducate that the structure integrity of collagen is still maintained obviously after introducing dencichine. Furthermore, we also analyze the mechanism of the combination, which is just more than hydrogen bonding. Moreover, differential scanning calorimetry (DSC) reveals that compared to pure collagen, dencichine could promote the thermalstability of collagen-dencichine composite sponge (CDCS) with the increasing content of dencichine. Atomic force microscopy (AFM) is utilized to determine the morphology changes of collagen by inducing dencichine. The fibril aggregation occurs due to the crosslinking with dencichine and the fibrous structure of collagen after inducing dencichine still remains compact and clear, which is the foundation of its biological activity. The present study, reveals that intermolecular interactions exist in the CDCS indeed, which is benefit for the development of new biological material and fabrication of novel functionalized hemostatic biomaterials. POLYM. COMPOS., 37:2027-2036, 2016. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Aiming to study the effect of particle size on the wear property of magnetorheological fluid (MRF), experiment materials, preparation process, and test methods are elaborated, and three different MRF samples consisting of particles of different size are prepared. Test experiments are carried out and the effect of particle size on the wear property of MRF is discussed. Moreover, the microstructures of particles extracted from MRF obtained before and after the wear experiments are observed by scanning electron microscope (SEM). Experimental results show that the particle size has a significant effect on wear property of MRF. Furthermore, the MRF with particles of 1.5–2.8 μm diameter on average is good for the requirement of engineering applications. [ABSTRACT FROM AUTHOR]

This paper uses a non-parametric test, based on consistently estimated discrimination accuracy defined as concordance probability between quantitative predictor and outcome, to compare paired biomarkers in predicting a health outcome, possibly subject to random censoring. Comparing with the Wilcoxon test for paired predictors based on Harrell's C-index, we found that the proposed test is better in presence of random censoring, although the two unbiased tests are equivalent for outcome either uncensored or censored by a constant. A simulation study also demonstrates that the bias in estimated difference in concordance probability, due to ignoring random censoring, results in overestimated power, especially when random censoring is heavy. The method was applied in two studies, where the biomarkers measured from the same study subjects are correlated. The first study on 299 school children in Bangladesh found the associations that higher blood arsenic and manganese were related to lower intellectual test scores, while the differences between the biomarkers in predicting the intellectual test scores were not statistically significant. The second study on 418 patients with primary biliary cirrhosis found that the baseline serum bilirubin had greater discrimination accuracy than the baseline serum albumin in predicting survival time. [ABSTRACT FROM AUTHOR]

A tough aerogel electrode of manganese oxide and polyaniline was prepared by in situ gelation, freeze-drying, and heat treatment on carbon cloth. The porous structure endows the final aerogel electrode with high electrochemical performance even at high current density and excellent cycling stability. [ABSTRACT FROM AUTHOR]

The aim of this study is to evaluate the chemical crosslinking effects of the natural derived chitosan dialdehyde (OCS) on collagen. Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC) and circular dichroism (CD) measurements suggest that introducing OCS might not destroy the natural triple helix conformation of collagen but enhance the thermal-stability of collagen. Meanwhile, a denser fibrous network of cross-linked collagen is observed by atomic force microscopy. Further, scanning electron microscopy (SEM) and aggregation kinetics analysis confirm that the fibrillation process of collagen advances successfully and OCS could lengthen the completion time of collagen fibrillogenesis but raise the reconstitution rate of collagen fibrils or microfibrils. Besides, the cytocompatibility analysis implies that when the dosage of OCS is less than 15%, introducing OCS into collagen might be favorable for the cell's adhesion, growth and proliferation. Taken as a whole, the present study demonstrates that OCS might be an ideal crosslinker for the chemical fixation of collagen. [ABSTRACT FROM AUTHOR]

Virtual reality in chemical engineering features real-time simulation of complex industrial processes by utilizing multi-scale computation paradigm, and its realization is premised on global hydrodynamic modeling of the processes. Initial energy-minimization multi-scale (EMMS) model, though originally proposed for gas–solid fast fluidization, is extended to bubbling fluidization and in both axial and radial directions, so as to enable unified modeling of the entire gas–solid fluidization regime and theoretical computation of axial and radial heterogeneities in gas–solid flow. By applying the EMMS and its extension models to the segments divided from complex gas–solid reactors, an EMMS-based general method is proposed for global hydrodynamic calculation of the complex systems. Compared with traditional empirical schemes, the EMMS-based method avoids pre-separating the complex systems into various reaction zones until each has a single and simple flow state. And its feasibility is demonstrated by performing full-loop computation of an industrial-scale circulating fluidized bed, but its flexibility to the complexities of industrial processes in configuration and hydrodynamics still needs to be increased further in order to develop a software package for chemical process and virtual reality technology development. [ABSTRACT FROM AUTHOR]

Exposure to arsenic (As) in drinking water is a widespread public health problem leading to increased risk for multiple outcomes such as cancer, cardiovascular disease, and possibly renal disease; potential mechanisms include inflammation and oxidative stress. We tested the hypothesis that As exposure is associated with increased inflammation and decreased estimated glomerular filtration rate (eGFR) and examined whether the effects of As were modified by plasma glutathione (GSH), glutathione disulfide (GSSG), or the reduction potential of the GSSG/2GSH pair ( E h GSH). In a cross-sectional study of N = 374 Bangladeshi adults having a wide range of As exposure, we measured markers of inflammation (plasma C-reactive protein (CRP), α-1 acid glycoprotein (AGP)), renal function (eGFR), GSH, and GSSG. In covariate-adjusted models, a 10% increase in water As, urinary As adjusted for specific gravity (uAs), or blood As (bAs) was associated with a 0.74% ( p = 0.01), 0.90% ( p = 0.16), and 1.39% ( p = 0.07) increase in CRP, respectively; there was no association with AGP. A 10% increase in uAs or bAs was associated with an average reduction in eGFR of 0.16 ( p = 0.12) and 0.21 ml/min/1.73 m 2 ( p = 0.08), respectively. In stratified analyses, the effect of As exposure on CRP was observed only in participants having E h GSH > median (uAs p Wald = 0.03; bAs p Wald = 0.05). This was primarily driven by stronger effects of As exposure on CRP in participants with lower plasma GSH. The effects of As exposure on eGFR were not modified significantly by E h GSH, GSH, or GSSG. These data suggest that participants having lower plasma GSH and a more oxidized plasma E h GSH are at increased risk for As-induced inflammation. Future studies should evaluate whether antioxidant treatment lowers plasma E h GSH and reduces risk for As-induced diseases. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two new Bacillidium species is described from Branchiura sowerbyi in China. • A novel type of exospore is observed in B. sinensis n. sp. • These two new species are most genetically similar with Janacekia tainanus , not the congeners. • Phylogenetic analyses placed two new species within the Bacillidium-Janacekia-Jirovecia clade. Bacillidium spp. exclusively infect oligochaetes and these microsporidian pathogens are typically characterized by their rod-shaped spores. Seven Bacillidium spp. are presently reported from different organs of oligochaetes. Here, we describe two new Bacillidium species, Bacillidium sinensis n. sp. and Bacillidium branchilis n. sp., from coelomocytes of Branchiura sowerbyi. This is the first report of Bacillidium spp. in oligochaetes from China. Both species of Bacillidium elicit the formations of opaque xenoma-like lesions in coelomocytes of the host. A diplokaryotic nucleus occurs in all life stages of these two new Bacillidium species. Mature spores of B. sinensis are 15.9 ± 0.6 (14.7–17.1) μm long (average ± standard error, range, n = 50) and 2.5 ± 0.1 (2.3–2.7) μm wide in fresh preparations. A new type of exospore (sixteen-layered exospore) is discovered from B. sinensis n. sp. which is distinctly different from B. branchilis n. sp., and other Bacillidium spp. (double-layered exospore) reported previously. These two Bacillidium species are morphologically distinguished from each other and all Bacillidium spp. described previously in terms of hosts, infection sites, spore size, spore wall or polar filament thickness. BLASTn searches indicated that these two new microsporidian parasites are surprisingly most similar to Janacekia tainanus (94.76% for B. sinensis and 90. 2% for B. branchilis) isolated from the fat body of midge larva (Kiefferulus tainanus). Phylogenetic analysis demonstrates that the two novel taxons cluster with J. debaisieuxi, J. tainanus , and Bacillidium sp. within the Jirovecia-Bacillidium-Janacekia clade. Other available 18S rRNA gene sequences for microsporidia that infect oligochaetes include J. sinensis , B. vesiculoformis , Neoflabelliforma aurantiae , and Bacillidium sp., but these do not form a single cluster with B. sinensis and B. branchilis , but are instead dispersed through the clade. Based on the ultrastructural features and molecular characteristics, two new species within the genus Bacillidium, B. sinensis n. sp. and B. branchilis n. sp., are designated. [ABSTRACT FROM AUTHOR]

[Display omitted] • Naidispora caidianensis n. gen. n. sp. is described from an oligochaete in China. • Sporophorous vesicle appeared during sporoblasts but degenerated in mature spores. • Phylogenetic analyses indicated that N. caidianensis formed an independent clade. • Molecular analysis suggested significant diversity within oligochaete microsporidia. A new microsporidian parasite, Naidispora caidianensis n. gen. n. sp. was found in coelomocytes of oligochaete Branchiura sowerbyi Beddard, 1892 from Wuhan city, Hubei Province, China. Opaque, hypertrophied coelomocytes (0.17–0.24 mm in diameter) depicted clinical signs of infection. Electron microscopy revealed a microsporidian with monokaryotic life stages. Rounded uninucleate meronts subsequently transformed into multinucleate merogonial plasmodia with masses of electron-dense projections on their plasma membrane. Electron–dense sporogonial plasmodia separated into uninucleate sporonts through rosette-like budding, and further developed into sporoblasts, enclosed by a sporophorous vesicle. Uninucleate mature spores were pyriform, measured 4.1 ± 0.1 (3.9–4.3) μm × 2.1 ± 0.07 (1.9–2.2) μm (average ± SE, range, n = 50), and contained a mushroom-like anchoring disk, bipartite polaroplast, electron-lucent posterior vacuole, trilaminar spore wall and 12–14 turns of an isofilar polar filament arranged in 2–3 ranks. The 1542 bp sequence from B. soweryi showed the highest similarity (below 80 %) with Nematocenator marisprofundi (accession number: JX463178). SSU rRNA gene-based phylogenetic analysis demonstrated that the novel taxon formed an independent clade from known microsporidian parasites. Based on the ultrastructural features and SSU rRNA gene sequence, we propose the establishment of a novel genus (Naidispora n. gen.) and species (Naidispora caidianensis n. sp.) to contain this parasite. [ABSTRACT FROM AUTHOR]

In biomedical research and practice, continuous biomarkers are often used for diagnosis and prognosis, with a cut-point being established on the measurement to aid binary classification. When survival time is examined for the purposes of disease prognostication and is found to be related to the baseline measure of a biomarker, employing a single cut-point on the biomarker may not be very informative. Using survival time-dependent sensitivity and specificity, we extend a concordance probability-based objective function to select survival time-related cut-points. To estimate the objective function with censored survival data, we adopt a non-parametric procedure for time-dependent receiver operational characteristics curves, which uses nearest neighbor estimation techniques. In a simulation study, the proposed method, when used to select a cut-point to optimally predict survival at a given time within a specified range, yields satisfactory results. We apply the procedure to estimate survival time-dependent cut-point on the prognostic biomarker of serum bilirubin among patients with primary biliary cirrhosis. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background: Although maternal hypothyroidism increases the risk of adverse neonatal and obstetric outcomes as well as lower IQ in children, the environmental determinants of maternal thyroid dysfunction have yet to be fully explored. Objectives: We aimed to examine associations between mid-pregnancy blood lead (BPb) and concomitant measures of thyroid function among participants in the Yugoslavia Prospective Study of Environmental Lead Exposure. Methods: As part of a population-based prospective study of two towns in Kosovo—one with high levels of environmental lead and one with low—women were recruited during the second trimester of pregnancy, at which time blood samples and questionnaire data were collected. We measured concentrations of BPb, free thyroxine (FT4), thyroid-stimulating hormone (TSH), and thyroid peroxidase antibodies (TPOAb) in archived serum samples. Results: Compared with women from the unexposed town, women from the exposed town had lower mean FT4 (0.91 ± 0.17 vs. 1.03 ± 0.16 ng/dL), higher mean TPOAb (15.45 ± 33.08 vs. 5.12 ± 6.38 IU/mL), and higher mean BPb (20.00 ± 6.99 vs. 5.57 ± 2.01 μg/dL). No differences in TSH levels were found. After adjustment for potential confounders, for each natural log unit increase in BPb, FT4 decreased by 0.074 ng/dL (95% CI: –0.10, –0.046 ng/dL), and the odds ratio for testing positive to TPOAb was 2.41 (95% CI: 1.53, 3.82). We found no association between BPb and TSH. Conclusions: Prolonged lead exposure may contribute to maternal thyroid dysfunction by stimulating autoimmunity to the thyroid gland. [ABSTRACT FROM AUTHOR]

Extant research has demonstrated the positive intrapersonal effects of mindfulness training. However, the cognitive mechanisms underlying the effects of mindfulness training on interpersonal processes are less clear. Here, we combined a randomized control mindfulness training design with computational approach to moral decision-making and moral judgments. Participants were randomly assigned to a Training group (N = 32) who received an 8-week mindfulness training or a Control group (N = 26) who waited for the same period of time. Before and after the 8-week period, participants completed a moral decision-making task, where they made tradeoff between money for themselves and unpleasant electric shocks to another person, and a moral judgment task, where they evaluated the blameworthiness of someone else's choices in the same moral decision-making task. Trait mindfulness, as measured by the Five-Facet Mindfulness Questionnaire, significantly increased from the pre- to post-training session for the Training group, but not the Control group, demonstrating the effectiveness of the mindfulness manipulation. For the Control group, participants' moral preference in both the decision-making task and the judgment task declined over time, exhibiting a "slippery slope" effect. In contrast, for the Training group, mindfulness training prevented moral preferences from declining. Computational modeling revealed that mindfulness training specifically reduced the increase in the weights of money over time in both the decision-making and judgment tasks, thereby curbing the "slippery slope" effects. These findings provide a cognitive account of the prosocial effects of mindfulness training on moral decision-making and moral judgments. [ABSTRACT FROM AUTHOR]

Hydrodynamic modeling of gas–solidbubbling fluidizationis of significance to the development of gas–solid bubblingreactors since it still remains at the stage of experimental and empiricalscience. As is the role of particle clusters in gas–solid fastfluidization, gas bubbles characterize the structural heterogeneityof gas–solid bubbling fluidization, and their evolution ismainly subject to the constraints of the stability and boundary conditionsof the system. By considering the expansion work of gas bubbles againstthe normal pressure stress in the emulsion phase, an improved necessarystability condition is proposed to close a gas–solid bubblingmodel. Applying the upgraded gas–solid bubbling model at thescale of vessels, the steady-state hydrodynamics of gas–solidbubbling fluidization can be reproduced without introducing bubble-specificempirical correlations such as for diameter and/or acceleration. Theunified modeling of the entire gas–solid fluidization regimefrom bubbling to fast fluidization is performed by integrating theupgraded gas–solid bubbling model with the original energy-minimizationmultiscale (EMMS) model. Incorporating the upgraded gas–solidbubbling model into commercial computational fluid dynamics (CFD)software at the scale of computational cells, the unsteady-state simulationof gas–solid bubbling fluidization is realized with a higheraccuracy than that based on homogeneous drag models. [ABSTRACT FROM AUTHOR]

Aiming to improve the flexibility of virtual maintenance operations, virtual hand was designed and applied in a virtual maintenance system. The structure of virtual hand was designed according to the real human hand and the frequently used gestures of virtual hand were elaborated. Moreover, the motion mapping from human hand to virtual hand was established and a framework which described the interaction mechanism of virtual maintenance system with virtual hand was proposed. Finally, a prototype system was developed and an example of scraper conveyor was provided. The application results indicated that virtual hand can simulate most of operations through real human hand and the flexibility of virtual maintenance operations was improved. [ABSTRACT FROM AUTHOR]

In order to improve the quality and efficiency of assembly sequence planning for complex mechanical product, a converse method-based approach for assembly sequence planning is proposed. Firstly, the disassembly interference matrix of product and the disassembly constraint degree of part are defined. Product disassembly sequence is obtained through geometry reasoning algorithm and the searching work of disassembly sequence is simplified by the contact constraint set. Secondly, the maneuverability of tool is inspected through the using matrix and interference matrix of assembly tool. The infeasible disassembly sequence is excluded and product assembly sequence is obtained by reversing the order of disassembly sequence. Thirdly, the evaluation mechanism for assembly sequence is established to get the optimal assembly sequence and the optimal assembly sequence is selected by calculating the value of evaluation function. Finally, a vibration generator is illustrated to verify the validity and feasibility of the proposed approach. [ABSTRACT FROM AUTHOR]

Remote photoplethysmography (rPPG) is a video-based non-contact heart rate measurement technology. It is a fact that most existing rPPG methods fail to deal with the spatiotemporal features of the video, which is significant for the extraction of the rPPG signal. In this paper, we propose a 3D central difference convolutional network (CDCA-rPPGNet) to measure heart rate, with an attention mechanism to combine spatial and temporal features. First, we crop and stitch the region of interest together through facial landmarks. Next, the high-quality regions of interest are fed to CDCA-rPPGNet based on a central difference convolution, which can enhance the spatiotemporal representation and capture rich relevant time contexts by collecting time difference information. In addition, we integrate the attention module into the neural network, aiming to strengthen the ability of the neural network to extract video channels and spatial features, so as to obtain more accurate rPPG signals. In summary, the three main contributions of this paper are as follows: (1) the proposed network base on central difference convolution could better capture the subtle color changes to recover the rPPG signals; (2) the proposed ROI extraction method provides high-quality input to the network; (3) the attention module is used to strengthen the ability of the network to extract features. Extensive experiments are conducted on two public datasets—the PURE dataset and the UBFC-rPPG dataset. In terms of the experiment results, our proposed method achieves 0.46 MAE (bpm), 0.90 RMSE (bpm) and 0.99 R value of Pearson's correlation coefficient on the PURE dataset, and 0.60 MAE (bpm), 1.38 RMSE (bpm) and 0.99 R value of Pearson's correlation coefficient on the UBFC dataset, which proves the effectiveness of our proposed approach. [ABSTRACT FROM AUTHOR]

Abstract: Axial heterogeneity in circulating fluidized bed (CFB) risers is very important to the design of fluidized bed reactors, which is, however, still unable to be described in theory. Based on a successful description of local hydrodynamics in gas–solid flow, the Energy-Minimization Multi-Scale (EMMS) theory further relates axial hydrodynamics with local and global stability conditions in the system, providing a theoretical way to account for the axial heterogeneity in CFB risers. This research reveals that the interaction between particle clusters and the dilute phase as well as the surrounding dense phase has a significant effect on their dynamical evolution. Similar to cluster diameter in the EMMS theory, number density of particle clusters serving as a comprehensive indicator to the heterogeneity in gas–solid flow is constrained by both local and global stability conditions in the system. With the above cognition, a one-dimensional EMMS model is developed to perform steady-state modeling of the axial heterogeneity in CFB risers. The model successfully reproduces a complete transition zone and the parametric effects on it at the choking condition. The S-shaped axial voidage profile calculated by the one-dimensional EMMS model is in good agreement with the experimental results in gas–solid fast fluidization. This research is not only the first step toward implementing the three-scale computation in virtual process engineering (VPE), but also of referential significance to industrial chemical process development. [Copyright &y& Elsevier]

Abstract: Organochlorine pesticides (OCPs) are persistent endocrine disruptors. OCPs cross the placenta; this prenatal exposure has been associated with adverse pregnancy outcomes. We investigated associations between prenatal exposure to OCPs and gestational age and birth weight in 600 infants born between 1960 and 1963. The primary OCP was 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (p,p′-DDT), its primary metabolite, 1,1′-dichloro-2,2′-bis(p-chlorophenyl)ethylene (p,p′-DDE) and the contaminant, 1,1,1-trichloro-2-(p-chlorophenyl)-2-(o-chlorophenyl)-ethane (o,p′-DDT). Regression analysis indicated that for each natural log unit increase in p,p′-DDT, birth weight increased by 274g (95% CI: 122, 425) when controlling for p,p′-DDE and o,p′-DDT. At a given level of p,p′-DDT exposure, o,p′-DDT and p,p′-DDE were associated with decreased birth weight. p,p′-DDE was negatively associated with length of gestation, controlling for p,p′-DDT and o,p′-DDT. These findings suggest opposing associations between exposure to p,p′-DDT and p,p′-DDE and birth weight. We did not find evidence to support mediation by maternal thyroid hormone status nor that the association differed by sex. [Copyright &y& Elsevier]

In biomedical research and practice, quantitative tests or biomarkers are often used for diagnostic or screening purposes, with a cut point established on the quantitative measurement to aid binary classification. This paper introduces an alternative to the traditional methods based on the Youden index and the closest-to-(0, 1) criterion for threshold selection. A concordance probability evaluating the classification accuracy of a dichotomized measure is defined as an objective function of the possible cut point. A nonparametric approach is used to search for the optimal cut point maximizing the objective function. The procedure is shown to perform well in a simulation study. Using data from a real-world study of arsenic-induced skin lesions, we apply the method to a measure of blood arsenic levels, selecting a cut point to be used as a warning threshold. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Extrusion has become one of the most popular techniques in food processing, and the process parameters are closely related to product quality. Purslane (Portulaca oleracea L.) can be used in medical and food products as a vegetable and herb. It has limited application in extrusion. The effects of extrusion process variables (screw speed, barrel temperature, and feed moisture) on system variables (specific mechanical energy [SME], die head pressure, and torque) and target variables (water absorption index, water solubility index, iodine blue value, color, pasting properties, and textural properties) of purslane powder compound rice were studied. The results showed that SME was moderately positively correlated with screw speed (r = 0.608, p < 0.05). However, torque was moderately negatively correlated with feed moisture (r = −0.574, p < 0.05), and die head pressure was moderately negatively correlated with barrel temperature (r = −0.635, p < 0.01). The target variables of extrudates were also correlated with the system parameters to varying degrees. These results are helpful to control and predict the texture, pasting properties, and other quality characteristics of extruded products containing purslane powder. Practical Application: The results showed that torque and die head pressure were moderately negatively related to barrel temperature, specific mechanical energy was moderately positively related to screw speed, peak viscosity and breakdown viscosity were moderately negatively related to specific mechanical energy, and water absorption index was moderately negatively related to torque and die head pressure. It provides a reference for the research of influencing system parameters and changing product quality by controlling extrusion process parameters. In this study, some possibilities for the application of broken rice and purslane in extrusion processing were proposed. [ABSTRACT FROM AUTHOR]

Abstract: Gas–solid interaction does exist both outside and inside particle clusters in gas–solid two-phase flow, but the penetrating flow through clusters was generally neglected in most mathematical models of clusters. As regards to what extent the penetrating flow exists in gas–solid flow and how the penetrating flow affects gas–solid interaction, there are still no universally accepted viewpoint and quantitative characterization until now. By utilizing both CFD (Computational Fluid Dynamics) simulations and PIV (Particle Image Velocimetry) measurements, this article quantitatively investigates the gas and dilute gas–solid penetrating flows through different pseudo two-dimensional clusters in a two-dimensional gas–solid fluidized bed. The solid penetrating flow through clusters seldom occurs, but the gas penetrating flow increases exponentially with increasing internal voidage of clusters, which is however affected little by superficial gas velocity under the tested operating conditions. These results imply that the effect of the gas penetrating flow through clusters must be taken into consideration when investigating particle clustering behavior in gas–solid two-phase flow. [Copyright &y& Elsevier]

Abstract: Pelletization of torrefied sawdust from a fluidized bed reactor was investigated to quantify the energy consumption and pellet properties, including moisture adsorption, pellet density and Meyer hardness. Energy consumptions in compaction and extrusion for torrefied sawdust were significantly higher than those for untreated sawdust at the same compression temperature, while the moisture uptake rate of pellets decreased with increasing the severity of torrefaction. The densities of torrefied pellets were lower than the control pellet due to the loss of chemically bonded water and low-melting point compounds during torrefaction which act as a binding agent when softened at ∼100°C. The properties of pellets were affected by the removal of most low-melting or – softening point components. [Copyright &y& Elsevier]

Abstract: Objective: Leonurine, a bioactive alkaloid compound in Herba leonuri, has various pharmacological activities, including antioxidant and anti-apoptotic capacities. This study was conducted to test the hypothesis that leonurine was able to attenuate tumor necrosis factor (TNF)-α-induced human umbilical vein endothelial cells (HUVEC) activation and the underlying molecular mechanisms. Methods: Mitogen-activated protein kinases (MAPK) activation, nuclear factor-κB (NF-κB) activation, and inflammatory mediators expression were detected by Western blot or enzyme-liked immunosorbent assay, intracellular reactive oxygen species (ROS) and NF-κB p65 translocation were measured by immunofluorescence, endothelial cell–monocyte interaction was detected by microscope. Results: Leonurine inhibited U937 cells adhesion to TNF-α-activated HUVEC in a concentration dependent manner. Treatment with leonurine blocked TNF-α-induced mRNA and protein expression of adhesion molecules (intercellular adhesion molecule-1 and vascular cell adhesion molecule-1), cyclooxygenase-2, and monocyte chemoattractant protein-1 in endothelial cells. In addition, leonurine attenuated TNF-α-induced intracellular ROS production in HUVEC. Furthermore, leonurine also suppressed the TNF-α-activated p38 phosphorylation and IκBα degradation. Subsequently, reduced NF-κB p65 phosphorylation, nuclear translocation, and DNA-binding activity were also observed. Conclusions: Our results demonstrated for the first time that the anti-inflammatory properties of leonurine in endothelial cells, at least in part, through suppression of NF-κB activation, which may have a potential therapeutic use for inflammatory vascular diseases. [Copyright &y& Elsevier]

In order to realize automation and intelligence of product disassembly process in a virtual maintenance environment, an improved max-min ant system based methodology for product disassembly sequence planning was proposed. The feasibility graph for product disassembly process was defined and the mathematic model of product disassembly sequence planning problem was set up. Thus, the problem of product disassembly sequence planning was transformed into the problem of searching optimal path on a feasibility graph. Moreover, an improved max-min ant system based on the strategy of sorting elite ants was presented and the flowchart of the improved algorithm was designed. Finally, by simulation examples, the robustness and outperforming others of the improved algorithm were verified. [ABSTRACT FROM AUTHOR]

BACKGROUND: Research suggests that prenatal phthalate exposures affect child executive function and behavior. OBJECTIVE: We evaluated associations between phthalate metabolite concentrations in maternal prenatal urine and mental, motor, and behavioral development in children at 3 years of age. Methods: Mono-n-butyl phthalate (MnBP), monobenzyl phthalate (MBzP), monoisobutyl phthalate (MiBP), and four di-2-ethylhexyl phthalate metabolites were measured in a spot urine sample collected from 319 women during the third trimester. When children were 3 years of age, the Mental Development Index (MDI) and Psychomotor Development Index (PDI) were measured using the Bayley Scales of Infant Development II, and behavior problems were assessed by maternal report on the Child Behavior Checklist. RESULTS: Child PDI scores decreased with increasing loge MnBP [estimated adjusted β-coefficient = -2.81; 95% confidence interval (CI): -4.63, -1.0] and loge MiBP (β = -2.28; 95% CI: -3.90, -0.67); odds of motor delay increased significantly [per loge MnBP: estimated adjusted odds ratio (OR) = 1.64; 95% CI: 1.10, 2.44; per loge MiBP: adjusted OR =1.82; 95% CI: 1.24, 2.66]. In girls, MDI scores decreased with increasing loge MnBP (β = -2.67; 95% CI: -4.70, -0.65); the child sex difference in odds of mental delay was significant (p = 0.037). The ORs for clinically withdrawn behavior were 2.23 (95% CI: 1.27, 3.92) and 1.57 (95% CI: 1.07, 2.31) per loge unit increase in MnBP and MBzP, respectively; for clinically internalizing behaviors, the OR was 1.43 (95% CI: 1.01, 1.90) per loge unit increase in MBzP. Significant child sex differences were seen in associations between MnBP and MBzP and behaviors in internalizing domains (p < 0.05). CONCLUSION: Certain prenatal phthalate exposures may decrease child mental and motor development and increase internalizing behaviors. [ABSTRACT FROM AUTHOR]

Abstract: In the present work, stable fluidization of sawdust was achieved in a bench fluidized bed with an inclined orifice distributor without inert bed materials. A solids circulation pattern was established in the bed without the presence of slugging and channeling. The effects of treatment severity and weight loss on the solid product properties were identified. The decomposition of hemicelluloses was found to be responsible for the significant changes of chemical, physical and mechanical properties of the torrefied sawdust, including energy content, particle size distribution and moisture absorption capacity. The hydrophobicity of the torrefied sawdust was improved over the raw sawdust with a reduction of around 40wt.% in saturated water uptake rate, and enhanced with increasing the treatment severity due to the decomposition of hemicelluloses which are rich in hydroxyl groups. The results in this study provided the basis for torrefaction in fluidized bed reactors. [Copyright &y& Elsevier]

A published predictor model in a single-site cohort study (questionable dementia, QD) that contained episodic verbal memory (SRT total recall), informant report of function (FAQ), and MRI measures was tested using logistic regression and ROC analyses with comparable measures in a second multisite cohort study (Alzheimer's Disease Neuroimaging Initiative, ADNI). There were 126 patients in QD and 282 patients in ADNI with MCI followed for 3 years. Within each sample, the differences in AUCs between the statistical models were very similar. Adding hippocampal and entorhinal cortex volumes to the model containing AVLT/SRT, FAQ, age and MMSE increased the area under the curve (AUC) in ADNI but not QD, with sensitivity increasing by 2% in ADNI and 2% in QD for a fixed specificity of 80%. Conversely, adding episodic verbal memory (SRT/AVLT) and FAQ to the model containing age, Mini Mental State Exam (MMSE), hippocampal and entorhinal cortex volumes increased the AUC in ADNI and QD, with sensitivity increasing by 17% in ADNI and 10% in QD for 80% specificity. The predictor models showed similar differences from each other in both studies, supporting independent validation. MRI hippocampal and entorhinal cortex volumes showed limited added predictive utility to memory and function measures. [ABSTRACT FROM AUTHOR]

Abstract: Recently, epidemiologic studies of developmental neurotoxicology have been challenged to increase focus on co-exposure to multiple toxicants. Earlier reports, including our own work in Bangladesh, have demonstrated independent associations between neurobehavioral function and exposure to both arsenic (As) and manganese (Mn) in school-aged children. Our earlier studies, however, were not designed to examine possible interactive effects of exposure to both As and Mn. To allow investigation of possible synergistic impact of simultaneous exposures, we recruited a new sample of 299 8–11 year old children, stratified by design on As (above and below 10μg/L) and Mn (above and below 500μg/L) concentrations of household wells. When adjusted only for each other, both As and Mn in whole blood (BAs; BMn) were significantly negatively related to most WISC-IV subscale scores. With further adjustment for socio-demographic features and ferritin, BMn remained significantly associated with reduced Perceptual Reasoning and Working Memory scores; associations for BAs, and for other subscales, were expectably negative, significantly for Verbal Comprehension. Urinary As (per gram creatinine) was significantly negatively associated with Verbal Comprehension scores, even with adjustment for BMn and other contributors. Mn by As interactions were not significant in adjusted or unadjusted models (all p''s>0.25). Findings are consistent with other reports documenting adverse impact of both As and Mn exposure on child developmental outcomes, although associations appear muted at these relatively low exposure levels. [Copyright &y& Elsevier]

This study examined ecstasy use and associated risk and protective factors among Asian American youth. Data from 996 Asian American adolescents and 1,108 Asian American young adults were used. Ecstasy use was relatively common among Asian American youth. Among adolescents, it was associated with older age, poor parent-child communication, having been approached by drug sellers, living in a metropolitan area, and positive attitudes toward substance use. Among Asian American young adults, it was associated with having been born in the United States, having been approached by drug sellers, criminal justice system involvement, and positive attitudes toward substance use. Implications for designing substance use prevention/intervention programs for this minority group are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Chromosomal aberrations are associated with increased cancer risk in adults. Previously, we demonstrated that stable aberrations involving chromosomes 1–6 in cord blood are associated with prenatal exposure to polycyclic aromatic hydrocarbons (PAHs) measured in air and are disproportionate to genomic content. We now examine whether the association with air PAHs is chromosome-specific and extends to smaller chromosomes. Using whole chromosome paints for chromosomes 1–6, 11, 12, 14 and 19, and a 6q sub-telomere specific probe, we scored 48 cord bloods (1500 metaphases per sample) from newborns monitored prenatally for airborne PAH exposure in the Columbia Center for Children''s Environmental Health cohort. Frequencies of stable aberrations were calculated as incident aberrations per 100 cell equivalents scored, and examined for association with airborne PAHs. Aberrations in chromosome 6 occurred more frequently than predicted by genomic content (p <0.008). Levels of both prenatal airborne PAHs and stable aberration frequency in chromosomes 1–6 decreased to half the levels reported previously in the same cohort (mean PAH decreased from 3.6 to 1.8ng/m3; mean stable aberration frequency from 0.56 to 0.24, SD=0.19). The mean stable aberration frequency was 0.45 (SD=0.15) in chromosomes 11–19. After adjusting for gender, ethnicity, and household smokers, the mean stable aberration frequency increased with increasing PAH exposure: with a doubling of prenatal PAH exposure, the mean stable aberration frequency for the chromosome1–6 group increased by a factor of 1.49 (95% CI: 0.84, 2.66; p =0.17); for chromosomes 11–19 mean stable aberration frequency increased by 2.00 (95% CI: 1.11, 3.62; p =0.02); for chromosome 6 alone, it increased by 3.16 (95% CI: 0.93, 10.77; p =0.06); there was no increase for chromosomes 1–5 (p >0.8). Aberrations in chromosomes 11, 12, 14, 19 and 6 were associated with prenatal exposure to PAHs in air, even at lower levels of PAH in air. The observed chromosome-specific effects of prenatal airborne PAHs raise concern about potential cancer risk. [Copyright &y& Elsevier]

Abstract: Leonurine, an alkaloid typically found in Herba leonuri, is known to have both antioxidant and cardioprotective properties. In the present study, we investigated the cardioprotective mechanism of leonurine the in vivo rat model of chronic myocardial ischemia and in vitro H9c2 cardiac myocyte model of oxidative stress. Myocardial ischemia was induced by ligating the left anterior descending coronary artery. Rats were divided into sham, myocardial ischemia+saline, and myocardial ischemia+leonurine (15mg/kg/day). Cardiac function was recorded by catheterization. Apoptosis-related factor vascular endothelial growth factor (VEGF), survivin, Bcl-2 and Bax and pro-survival signaling pathways Akt, hypoxia inducible factor (HIF)-1α were measured by Western blotting or RT-PCR. Our results showed leonurine significantly improved myocardial function as evidenced by the decreased left ventricle end-diastolic pressure and the increased +dP/dt. Interestingly, leonurine increased the phosphorylation of Akt, the protein and gene expression of Bcl-2, but it reduced the protein and gene expression of Bax in vivo. Meanwhile leonurine significantly increased Akt phosphorylation in a concentration-dependent manner in H9c2 cardiac myocyte induced by oxidative stress in vitro, which was abolished by a phosphoinositide 3-kinase (PI3K) inhibitor, LY294002. Furthermore, leonurine not only increased the expression of HIF-1α but also the expression of survivin and VEGF. The results of present study demonstrated, for the first time that leonurine has potent anti-apoptotic effects after chronic myocardial ischemia mediated by activating the PI3K/Akt signaling pathway. Angiogenic mechanisms may be partially responsible for such an effect, which needs to be studied further. [ABSTRACT FROM AUTHOR]

Abstract: Aims: To investigate trends in rates of ecstasy use among US adolescents from 1999 to 2008, and to examine the associations between the major sociodemographic factors, especially gender, and ecstasy use, during this period. Methods: The adolescent subsamples (age 12–17) from 1999 to 2008 NHSDA/NSDUH surveys were used for the current study. Data from adolescents’ self-reports on use of ecstasy and of other drugs, as well as sociodemographic characteristics, were used in the analyses. Results: There was an increasing trend in adolescent ecstasy use from 1999 to 2002, which was followed by a decreasing trend from 2002 to 2005, and a slight rise from 2005 to 2008. In contrast to some other drugs, ecstasy was more likely to be used by girls than by boys. This gender difference persisted over the 10-year period and could not be explained by other demographic factors. Conclusion: Given the known health consequences of ecstasy use, especially for females, the observed gender difference in adolescent ecstasy use should be taken into account by drug prevention and intervention programs. [Copyright &y& Elsevier]