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Stable operation of thermoelectric devices requires both p‐ and n‐type materials with desirable compatibility and similar application temperature range. However, n‐type GeTe‐based materials currently have a lower application temperature range (<525 K) than p‐type GeTe‐based materials (500–800 K) due to the strong bipolar effect. Here, it is demonstrated that the bipolar effect of n‐type GeTe can be inhibited by the combination of bandgap enlargement and minority carrier filtering. Specifically, reducing cation vacancies can enlarge the bandgap, while introducing localized heavy doping areas with relatively large bandgap can generate a minority carrier barrier in the valence band to block the minority carrier transport. Consequently, a record‐high power factor (5.3 µW cm−1 K−2) and figure‐of‐merit (zT) of 0.45 can be obtained at 723 K in n‐type Ge0.46Bi0.17Pb0.37Te0.7Se0.3. This work demonstrates that bipolar suppression is an effective strategy to realize high‐performance n‐type GeTe‐based materials in the mid‐temperature range, and correspondingly extends the applicability. [ABSTRACT FROM AUTHOR]

The design of water supply systems powered by solar photovoltaic (PV) systems are installed for irrigation and other allied applications at remote rural areas which lack proper on-grid power systems. These systems have been operating successfully for several decades at locations receiving ample solar radiation, assisting in the reduction of carbon emissions. Hybrid life cycle assessment was performed in this study to determine the carbon emissions for a solar PV water pumping system (SPVWPS) in Xilin Gol League, Inner Mongolia. The carbon emission (g/mm³) produced by 1 m³ of water raised by 1 m was used as a reference in this assessment. The present analysis estimates the net CO2 emissions generated during the stages of production, transportation, construction, operation, maintenance, and recycling of SPVWPS. The results from SPVWPS were compared with CO2 emissions from diesel operated pumping systems. It was discovered that the carbon emission intensity produced during the 25-year operation period of SPVWPS was 0.80 g/mm³. The major CO2 emissions of SPVWPS were generated during the manufacturing stage totaled 2.02t, accounting for 55.19% of total emissions. When compared to the mobile diesel-powered water supply project, the CO2 emission intensity from SWPS was found to be about 0.55 times lower by about 1.46 g/mm³. As a result, the rapid development of SPVWPS in rural and pastoral areas represents the realization of rural low-carbon transformation and development, as well as the achievement of China’s “double carbon” reduction targets by 2050. [ABSTRACT FROM AUTHOR]

Background: The pathogen of angiostrongyliasis is the parasite Angiostrongylus cantonensis, and the transcriptome profiling of the male adult was unclear. We aimed to understand how the male adults adapt, so the expression profile of A. cantonensis adult males was analyzed. Methods: In order to improve the understanding of the transcriptome of adult males, RNA from three groups of male adult A. cantonensis was extracted and reverse transcribed to construct cDNA libraries. After sequencing, annotation of unigenes and transcripts was performed by querying the NR (Non- Redundant Protein Sequence Database), GO (Gene Ontology) and COG/ KOG (Clusters of Orthologous Groups of proteins/euKaryotic Ortholog Groups) databases. Results: For each group of adults, 43,260,894 raw reads and 43,200,341 clean reads were obtained. After successful assembly, 87,649 unigenes and 146,895 transcripts were obtained. Annotation of the unigenes and transcripts was identical and male adults expressed a series of genes encoding proteins specific to the male gender at the adult stage, such as proteins involved in energy metabolism, energy synthesis and transport. Expression of the ribosome pathway suggests a relationship with the physical activities during the adult male stage. Conclusion: The transcriptome analysis is a good reference to understand further the expression profile of male adult A. cantonensis. [ABSTRACT FROM AUTHOR]

Dense point defects can strengthen phonon scattering to reduce the lattice thermal conductivity and induce outstanding thermoelectric performance in GeTe‐based materials. However, extra point defects inevitably enlarge carrier scattering and deteriorate carrier mobility. Herein, it is found that the interstitial Cu in GeTe can result in synergistic effects, which include: 1) strengthened phonon scattering, leading to ultralow lattice thermal conductivity of 0.48 W m−1 K−1 at 623 K; 2) weakened carrier scattering, contributing to high carrier mobility of 80 cm2 V−1 s−1 at 300 K; 3) optimized carrier concentration of 1.22 × 1020 cm−3. Correspondingly, a high figure‐of‐merit of ≈2.3 at 623 K can be obtained in the Ge0.93Ti0.01Bi0.06Te‐0.01Cu, which corresponds to a maximum energy conversion efficiency of ≈10% at a temperature difference of 423 K. This study systematically investigates the doping behavior of the interstitial Cu in GeTe‐based thermoelectric materials for the first time and demonstrates that the localized interstitial Cu is a new strategy to enhance the thermoelectric performance of GeTe‐based thermoelectric materials. [ABSTRACT FROM AUTHOR]

The Rokel River (RR) basin is one of the most neglected ichthyofaunal basins, despite the potential for undetected diversity and high levels of endemism. Data on the molecular phylogeny of freshwater fish from this river are rare. Morphological features alone are inadequate for precise species identification. Here, a phylogenetic analysis performed based on the mtDNA Cytb gene for eleven cyprinid fish from the RR basin recovered eleven distinct lineages. The same was also observed for two of our species delineation analyses, of which four are identical to six morphospecies, one is of taxonomic uncertainty, and the rest are currently unrecognized. The disjunct distribution found here in some cyprinid species from the RR basin and their sister species suggests that this river had a past complex historical inter-basin connection exchange with the nearby river basins of the Zaire and lower Guinean ecoregions. The unrecognized diversity observed from cyprinid species of this area may have significant implications for the conservation of biodiversity. [ABSTRACT FROM AUTHOR]

According to the Mott's relation, the figure‐of‐merit of a thermoelectric material depends on the charge carrier concentration and carrier mobility. This explains the observation that low thermoelectric properties of GeTe‐based materials suffer from the degraded carrier mobility, on account of the fluctuation of electronegativity and ionicity of various elements. Here, high‐performance CuBiSe2 alloyed GeTe with high carrier mobility due to the small electronegativity difference between Cu and Ge atoms and the weak ionicity of CuTe and BiTe bonds, is developed. Density functional theory calculations indicate that CuBiSe2 alloying increases the formation energy of Ge vacancies and correspondingly reduces the amount of Ge vacancies, leading to an optimized carrier concentration and a high power factor of ≈37.4 µW cm−1 K−2 at 723 K. Moreover, CuBiSe2 alloying induces dense point defects and triggers ubiquitous lattice distortions, leading to a reduced lattice thermal conductivity of 0.39 W m−1 K−1 at 723 K. These synergistic effects result in an optimization of the carrier mobility, the carrier concentration, and the lattice thermal conductivity, which favors an enhanced peak figure‐of‐merit of ≈2.2 at 723 K in (GeTe)0.94(CuBiSe2)0.06. This study provides guidance for the screening of GeTe‐based thermoelectric materials with high carrier mobility. [ABSTRACT FROM AUTHOR]

Learning and memory are assumed to be supported by mechanisms that involve cholinergic transmission and hippocampal theta. Using G protein-coupled receptor-activation-based acetylcholine sensor (GRABACh3.0) with a fiber-photometric fluorescence readout in mice, we found that cholinergic signaling in the hippocampus increased in parallel with theta/gamma power during walking and REM sleep, while ACh3.0 signal reached a minimum during hippocampal sharp-wave ripples (SPW-R). Unexpectedly, memory performance was impaired in a hippocampus-dependent spontaneous alternation task by selective optogenetic stimulation of medial septal cholinergic neurons when the stimulation was applied in the delay area but not in the central (choice) arm of the maze. Parallel with the decreased performance, optogenetic stimulation decreased the incidence of SPW-Rs. These findings suggest that septo-hippocampal interactions play a task-phase-dependent dual role in the maintenance of memory performance, including not only theta mechanisms but also SPW-Rs. [ABSTRACT FROM AUTHOR]

In order to solve the problem of poor robustness of the traditional method of calculating torque in the mechanical model of 7-DOF picking manipulator, this paper proposes a control strategy of calculating torque plus fuzzy compensation by using adaptive fuzzy logic system to compensate the uncertain part of the mechanical model of 7-DOF picking manipulator. By using Lagrange method, the dynamic model of 7-DOF manipulator is established, and the relationship between joint motion and applied torque (force) is obtained. Using ADAMS and MATLAB to establish a co-simulation platform, the manipulator and trajectory tracking control system are simulated. The results show that the trajectory tracking error of each joint in the algorithm is obviously reduced and the convergence trend is obvious. The average trajectory tracking accuracy of joint 1 to joint 7 was improved by 70.22%, 94.78%, 0.62%, 74.23%, 89.78%, 86.45%, and 67.15%, respectively. In this control scheme, the control force (moment) of each joint changes regularly, and the output force (moment) does not appear chattering and mutation when the disturbance signal is added. The research results can provide support for the further study of picking manipulator trajectory tracking control system. [ABSTRACT FROM AUTHOR]

The motion of cladding systems can be leveraged to mitigate natural and man-made hazards. The literature counts various examples of connections enhanced with passive energy dissipation capabilities at connections. However, because such devices are passive, their mitigation performance is typically limited to specific excitations. The authors have recently proposed a novel variable friction cladding connection capable of mitigating hazards semi-actively. The variable friction cladding connection is engineered to transfer lateral forces from the cladding element to the structural system. Its variation in friction force is generated by a toggle-actuated variable normal force applied onto sliding friction plates. In this study, a multiobjective motion-based design methodology integrating results from the previous work is proposed to leverage the variable friction cladding connection for nonsimultaneous wind, seismic, and blast hazard mitigation. The procedure starts with the quantification of each hazard and performance objectives. It is followed by the selection of dynamic parameters enabling prescribed performance under wind and seismic loads, after which an impact rubber bumper is designed to satisfy motion requirements under blast. Last, the peak building responses are computed and iterations conducted on the design parameters on the satisfaction of the motion objectives. The motion-based design procedure is verified through numerical simulations on two example buildings subjected to the three nonsimultaneous hazards. The performance of the variable friction cladding connection is also assessed and compared against different control cases. Results show that the motionbased design procedure yields a conservative design approach in meeting all of the motion requirements and that the variable friction cladding connection performs significantly well at mitigating vibrations. [ABSTRACT FROM AUTHOR]

Background: Although more information has become available on the occurrence of phthalates and di(2-ethylhexyl) adipate (DEHA) in foods including cow’s milk, information on their presence in human milk, the important and recommended sole diet for infants up to six months of age, is very limited, especially for DEHA. Objective: To develop a GC-MS method for simultaneous analysis of DEHA and phthalates in human milk samples and generate occurrence data for exposure assessment. Method: Human milk samples were extracted with acetonitrile followed by dispersive solid-phase extraction and GC-MS analysis. Results: Among the 305 human milk samples collected from the Canadian Maternal-Infant Research on Environmental Chemicals Study, some phthalates (DHxP, BBzP, and DOP) were not detected in any of the samples, while DEHA and the other phthalates (DMP, DEP, DBP, DiBP, and DEHP) were detected at low frequencies with levels from 30.4–237 ng/g in up to 31 of the 305 human milk samples. Conclusions: In general, DEHA and phthalates were detected at low frequencies and low levels in the 305 human milk samples. Highlights: A GC-MS method based on dispersive solid phase extraction was developed for analysis of DEHA and eight phthalates in 305 human milk samples for exposure assessment. [ABSTRACT FROM AUTHOR]

Noise-assistant transduction was investigated in coupled polymer chains where one subsystem was exposed to environment noise. It was found that coupling could transfer oscillation from one subsystem disturbed by noise to the other not disturbed by noise and play a role of a noise filtering for the other. Then, a sort of coupling-induced synchronization was investigated as a function of noise intensity and coupling strength. In particular, we calculated the minimum coupling strength to reach synchronization and pointed out that noise dominated at small coupling strength, otherwise, coupling dominated. [ABSTRACT FROM AUTHOR]

The article focuses on the history and evolution of the periodical highlighting its growth from its inception in 1915 as the Journal of the Association of Official Agricultural Chemists. Topics include key milestones such as the establishment of a manuscript review system in the 1950s, organizational name changes, and the recent advancements in hosting its contents on the Oxford Academic Platform since January 2020.

To facilitate the rational design of alloy catalysts, we introduce a method for rapidly calculating the structure and catalytic properties of a substitutional alloy surface that is in equilibrium with the underlying bulk phase. We implement our method by developing a way to generate surface cluster expansions that explicitly account for the lattice parameter of the bulk structure. This approach makes it possible to computationally map the structure of an alloy surface and statistically sample adsorbate binding energies at every point in the alloy phase diagram. When combined with a method for predicting catalytic activities from adsorbate binding energies, maps of catalytic activities at every point in the phase diagram can be created, enabling the identification of synthesis conditions likely to result in highly active catalysts. We demonstrate our approach by analyzing Pt-rich Pt-Ni catalysts for the oxygen reduction reaction, finding 2 regions in the phase diagram that are predicted to result in highly active catalysts. Our analysis indicates that the Pt3Ni(111) surface, which has the highest known specific activity for the oxygen reduction reaction, is likely able to achieve its high activity through the formation of an intermetallic phase with L12 order. We use the generated surface structure and catalytic activity maps to demonstrate how the intermetallic nature of this phase leads to high catalytic activity and discuss how the underlying principles can be used in catalysis design. We further discuss the importance of surface phases and demonstrate how they can dramatically affect catalytic activity. [ABSTRACT FROM AUTHOR]

Realizing the goal of the Paris Agreement to limit global warming to 2 °C by the end of this century will most likely require deployment of carbon-negative technologies. It is particularly important that China, as the world's top carbon emitter, avoids being locked into carbon-intensive, coal-fired power-generation technologies and undertakes a smooth transition from high-to negative-carbon electricity production. We focus here on deploying a combination of coal and biomass energy to produce electricity in China using an integrated gasification cycle system combined with carbon capture and storage (CBECCS). Such a system will also reduce air pollutant emissions, thus contributing to China's near-term goal of improving air quality. We evaluate the bus-bar electricity-generation prices for CBECCS with mixing ratios of crop residues varying from 0 to 100%, as well as associated costs for carbon mitigation and cobenefits for air quality. We find that CBECCS systems employing a crop residue ratio of 35% could produce electricity with net-zero life-cycle emissions of greenhouse gases, with a levelized cost of electricity of no more than 9.2 US cents per kilowatt hour. A carbon price of approximately $52.0 per ton would make CBECCS cost-competitive with pulverized coal power plants. Therefore, our results provide critical insights for designing a CBECCS strategy in China to harness nearterm air-quality cobenefits while laying the foundation for achieving negative carbon emissions in the long run. [ABSTRACT FROM AUTHOR]

The author presents updated and clarified scopes of the journal.

Understanding the host galaxy properties of stellar binary black hole (SBBH) mergers is important for revealing the origin of the SBBH gravitational wave sources detected by advanced LIGO and helpful for identifying their electromagnetic counterparts. Here, we present a comprehensive analysis of the host galaxy properties of SBBHs by implementing semi-analytical recipes for SBBH formation and merger into cosmological galaxy formation model. If the time delay between SBBH formation and merger ranges from ≲ Gyr to the Hubble time, SBBH mergers at redshift z ≲ 0.3 occur preferentially in big galaxies with stellar mass M* ≳ 2 × 1010 M⊙ and metallicities Z peaking at ∼0.6 Z⊙. However, the host galaxy stellar mass distribution of heavy SBBH mergers (M•• ≳ 50 M⊙) is bimodal with one peak at ∼109 M⊙ and the other peak at ∼2 × 1010 M⊙. The contribution fraction from host galaxies with Z ≲ 0.2 Z⊙ to heavy mergers is much larger than that to less heavy mergers. If SBBHs were formed in the early Universe (e.g. z > 6), their mergers detected at z ≲ 0.3 occur preferentially in even more massive galaxies with M* > 3 × 1010 M⊙ and in galaxies with metallicities mostly ≳ 0.2 Z⊙ and peaking at Z ∼ 0.6 Z⊙, due to later cosmic assembly and enrichment of their host galaxies. SBBH mergers at z ≲ 0.3 mainly occur in spiral galaxies, but the fraction of SBBH mergers that occur in elliptical galaxies can be significant if those SBBHs were formed in the early Universe; and about two-thirds of those mergers occur in the central galaxies of dark matter haloes. We also present results on the host galaxy properties of SBBH mergers at higher redshift. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate (surgical) visual outcomes in patients treated via supraorbital keyhole eyebrow incision approach. Data from 14 patients with TSMs (Tuberculum Sellae Meningioma) who underwent microsurgical treatment by a supraorbital keyhole eyebrow skin incision between September 2006 and September 2013 were retrospectively collected and analyzed. Patients were analyzed on the basis of clinical, radiological, and surgical factors that appeared to affect the outcome. To quantify the extent of ophthalmological disturbances Visual impairment score was used to analyze visual acuity and visual fi elds, which range from 0 (best) to 100 (worst). Change in visual function was assessed as the main outcome. The mean age of the 10 women and 4 men enrolled in the study was 56.50years (range, 42~74 years). The presenting symptom was asymmetrical visual loss in 71.4% of the patients. And examination revealed decreased visual acuity (Snellen notation) in 100% and impaired visual fi elds (Goldmann perimetry) in 58.3 % (7/12 cases, central scotoma and temporal anopia n=1, classical bitemporal hemianopia n=4, incongruent homonymous hemianopia n=2, 2 cases data N/A) of the patients. Simpson grades I resection via a supraorbital keyhole eyebrow skin incision approach, were achieved in 100% of the patients. Quality of life was assessed according to Karnofsky scale and was 86.67 (range: 70~100). The mean follow-up duration was 51.73 months (range: 27~91 months).No recurrent tumors were observed during this period. According to the fi ndings of this study, this approach provides a pleasing cosmetic outcome and also decreases brain manipulation while minimizing the likelihood of procedure-related morbidity. A favorable visual outcome was observed in most of the patients in the late postoperative period. [ABSTRACT FROM AUTHOR]

Pt-Ni nanoparticles are promising catalysts for the oxygen reduction reaction but they suffer from Ni dissolution in oxidizing conditions. It has recently been shown that it is possible to stabilize octahedral Pt-Ni nanoparticles by doping them with a small amount of Mo. Using ab initio calculations and a quaternary cluster expansion, we provide atomic-scale explanations for the enhanced stability of Mo-doped Pt-Ni nanoparticles. We predict that for Mo-doped Pt3Ni nanoparticles with only a small amount of Mo doping (around 1.6% mole fraction) the equilibrium concentration of Ni atoms on the particle surface is greatly reduced, limiting the rate at which Ni atoms dissolve from the particles. Mo doping also increases Pt/Ni vacancy formation energies in the surface layer, which further stabilizes the nanoparticles against Ni dissolution and helps preserve the nanoparticle shape. Our calculations also reveal insights into the shape evolution of Pt-Ni nanoparticles: the preferential oxidation of edges can make (111) face sites more vulnerable to dissolution than edge sites, which may contribute to the observed formation of Pt-Ni nanoframes and nanoparticles with concave surfaces. [ABSTRACT FROM AUTHOR]

This paper investigates the performance of a novel semiactive damping device at mitigating nonsimultaneous multihazard loads. The device, termed modified friction device (MFD), has been previously proposed by the authors. It consists of a variable friction system based on automotive drum brake technology. The device has been demonstrated in a laboratory environment, and its dynamic behavior has been modeled. This model is used to conduct numerical simulations on two representative structures, one short building located in Japan and the other tall building located in Boston, MA. Simulated hazards include wind, blast, and seismic loads. Various control cases are considered, including semiactive control under five different sets of control weights, and passive viscous and passive friction to benchmark performance. Results show that the semiactive control cases outperforms all of the other cases for the vast majority of hazards and performance indices, provided that the right control weights are utilized. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is the most common primary brain tumor with median survival of approximately one year. This dismal poor prognosis is due to resistance to currently available chemotherapeutics; therefore, new cytotoxic agents are urgently needed. In the present study, we reported the cytotoxicity of toosendanin (TSN) in the GBM U87 and C6 cell lines in vitro and in vivo. By using the MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide) assay, flow cytometry analysis, andWestern blot, we found that TSN inhibited U87 and C6 cell proliferation and induced apoptosis at a concentration as low as 10 nM. Administration of TSN also reduced tumor burden in a xenograft model of athymic nude mice. Pharmacological and molecular studies suggested that estrogen receptor β (ERβ) and p53 were prominent targets for TSN. GBM cell apoptosis induced by TSN was a stepwise biological event involving the upregulation of ERβ and contextual activation of functional p53. Collectively, our study indicates, for the first time, that TSN is a candidate of novel anti-cancer drugs for GBM. Furthermore, ERβ and p53 could act as predictive biomarkers for the sensitivity of cancer to TSN. [ABSTRACT FROM AUTHOR]

This paper describes and discusses the vibration serviceability of the innovative prestressed cable-reinforced concrete truss (i.e., prestressed cable RC truss, PCT for abbreviation) floor system subjected to heel-drop impact loading, based on the theoretical and experimental studies. In the theoretical analysis, the PCT floor system is idealized as an anisotropic rectangular plate with four built-in edges and the weighted residual method was used. A field test was carried out to investigate the dynamic characteristics of the PCT floor system and to validate and demonstrate the convergence of the theoretical solution. As a result, the experimental results agree well with the theoretical ones. The decrease of vibration is dramatic in the direction perpendicular to the PCT girder and is at a slower rate along the direction of the girder. The investigated PCT floor system has a low fundamental natural frequency (<4 Hz) with low damping ratio (≈2%). According to one standard of vibration criteria, the innovative floor system exhibits satisfactory vibration perceptibility. [ABSTRACT FROM AUTHOR]

Surface transfer doping of hydrogen-terminated diamond has been achieved utilising V2O5 as a surface electron accepting material. Contact between the oxide and diamond surface promotes the transfer of electrons from the diamond into the V2O5 as revealed by the synchrotron-based high resolution photoemission spectroscopy. Electrical characterization by Hall measurement performed before and after V2O5 deposition shows an increase in hole carrier concentration in the diamond from 3.0 x 1012 to 1.8 x 1013cm-2 at room temperature. High temperature Hall measurements performed up to 300 °C in atmosphere reveal greatly enhanced thermal stability of the hole channel produced using V2O5 in comparison with an air-induced surface conduction channel. Transfer doping of hydrogen-terminated diamond using high electron affinity oxides such as V2O5 is a promising approach for achieving thermally stable, high performance diamond based devices in comparison with air-induced surface transfer doping. [ABSTRACT FROM AUTHOR]

Danshen is one of the most frequently used traditional Chinese herbs owing to its remarkable and reliable therapeutic effects. Phenolic acids and diterpenoids have proved to be the bioactive substance groups. In order to fully profile its chemical compositions and explore new potential bioactive compounds, a comprehensive two-dimensional liquid chromatography system coupled to DAD detector and hybrid linear ion trap (LTQ) Orbitrap mass spectrometry (LC × LC-DAD-ESI/HRMS/MSn) was set up in this study based on the column combination of Hypersil gold CN (150 mm × 1 mm, 3 μm) and Accucore C18 (50 mm × 4.6 mm, 2.6 μm). Using the optimal segment gradient program, phenolic acids and diterpenoids were separated into two independent groups and a total of 328 peaks were successfully detected on the contour plot of Danshen. By means of the accurate mass and reliable MSn data, 102 compounds were identified or tentatively identified and 7 of them were discovered from Danshen for the first time. Moreover, the LC × LC-DAD system was validated for the quantitative analysis of 14 bioactive analytes using the contour plot, exhibiting satisfactory linearity (r ≥ 0.9976) and high precision for both peak locating (≤1.07%) and peak volume calculating (0.34%-4.11%). The established method could afford powerful separation capability, reliable identification data and accurate quantitative results, which is very suitable for analysis of complex herbal samples. [ABSTRACT FROM AUTHOR]

In order to improve the accuracy of crosslinked polyethylene (XLPE) cable status diagnosis and eliminate redundant features, this paper proposes a feature selection method for XLPE cable status diagnosis based on particle swarm optimization algorithm to optimize support vector machine. Firstly, this paper constructs 31 binary coded feature combinations based on five commonly used feature parameters for XLPE cable detection. Secondly, the optimal feature subset is selected based on the average accuracy of 20 cross-validation of PSO-SVM under 31 different feature combinations. Finally, train the diagnostic model with the optimal feature subset and its corresponding parameters, and verify the diagnostic performance of the selected features with test set samples and XLPE cable field data. The experimental results show that the PSO-SVM feature selection method can effectively find the optimal feature subset. The number of features selected in this paper is 2, and the classification accuracy of the test set is 98%. Compared with the preferred features of traditional feature selection methods, the features selected in this paper have good generalization ability. [ABSTRACT FROM AUTHOR]

A sensitive and selective gas chromatography-mass spectrometry method was developed and validated for simultaneous analysis of bisphenol A (BPA) and three other bisphenols, bisphenol B (BPB), bisphenol E (BPE), and bisphenol F (BPF). This method was used to analyze samples of 52 canned fish products to follow up a previous study conducted 5 years ago to investigate any changes in BPA levels since then and levels of other bisphenols due to possible changes in can coating formulations. BPB and BPE were not detected in any of the 52 canned fish products, and BPF was detected in only four products at low levels from 1.8 to 5.7 ng/g, indicating that BPA is likely still the dominant bisphenol used in current can coating formulations. BPA was detected in all 52 canned fish products, but at much lower levels compared with a previous study; levels ranged from 0.96 to 265 ng/g (average, 28 ng/g). The few products with high BPA levels (>100 ng/g) are exclusively from a new brand that has become available on the market only recently. Further analysis of canned fish products is planned in the future to capture any changes in BPA levels in these products and to update the exposure assessment of BPA due to consumption of canned fish products. [ABSTRACT FROM AUTHOR]

The large deflection condition of a bimodular plate may yield a dual nonlinear problem where the superposition theorem is inapplicable. In this study, the bimodular Föppl-von Kármán equations of a plate subjected to the combined action of a uniformly distributed load and a centrally concentrated force are solved using a biparametric perturbation method. First, the deflection and radial membrane stress were expanded in double power series with respect to the two types of loads. However, the biparametric perturbation solution obtained exhibited a relatively slow rate of convergence. Next, by introducing a generalized load and its corresponding generalized displacement, the solution is expanded in a single power series with respect to the generalized displacement parameter, thereby leading to the better convergence on the solution. A numerical simulation is also used to verify the correctness of the biparametric perturbation solution. The introduction of a bimodular effect will modify the stiffness of the plate to some extent. In particular, the bearing capacity of the plate will be strengthened further when the compressive modulus is greater than the tensile modulus. [ABSTRACT FROM AUTHOR]

Here we report the demonstration of a GHz-speed Lithium Niobate (LiNbO3) modulator that uses an amorphous Silicon waveguide to strongly confine light. The compact (<1 mm) modulator is realized by low-temperature deposition of hydrogenated amorphous Silicon (a-Si:H) onto a x-cut LiNbO3 substrate. The a-Si:H provides tight waveguide mode confinement while allowing strong evanescent coupling to the underlying LiNbO3 substrate which, in turn, enables efficient electro-optic modulation. This approach overcomes the traditional drawbacks of low-index contrast LiNbO3 waveguides and consequently is able to realize a strong Pockels effect in a densely integrated Silicon photonics platform. It is expected that this new Si-LiNbO3 platform will enable a multitude of devices and circuits for RF Photonics, nonlinear optics and quantum optics. [ABSTRACT FROM AUTHOR]

Background The omentum is one of the initial sites for peritoneal metastasis because it possesses milky spots that provide a microenvironment for cancer cells to readily migrate and grow into micrometastases. This study investigated the role of the CCL22-CCR4 axis in gastric cancer cells selectively infiltrating into milky spots. Methods Gastric cancer MFC cells labelled with DiI were injected intraperitoneally into strain 615 mice. The mice were euthanised at specified intervals and the omentum was excised for immunohistochemistry. The effects of CCL22 on the proliferation and migration of MFCs were assessed by MTT and trans-well assays. RT-PCR and Western blot analysis detected CCR4 mRNA and protein expression levels in MFCs. Immunohistochemistry was used to analyse CCL22 and CCR4 expression in the milky spot micrometastases. Results Two weeks after intraperitoneal injection, the milky spot areas were completely occupied by proliferating gastric cancer cells and cell cluster-type micrometastases were observed. In contrast, cancer cells formed single cell-type micrometastases in the non-milky spot areas. MFCs expressed CCR4, which was localised on the cell surface and or in the cytoplasm. Different concentrations of CCL22 significantly increased the proliferation ability of MFCs. Additionally, concentrations of CCL22 between 10-100 ng/ml significantly increased the migration of MFCs. Within omental milky spots, CCL22 was localised mainly on the cell surface and or in the cytoplasm. Within sections of omental milky spot micrometastases, CCR4 was recognised on or in gastric cancer cells, constituent cells milky spots, blood cells and blood endothelial cells. Conclusions Omental milky spots are a congenial microenvironment for peritoneal free gastric cancer cells to migrate, survive, and establish cell cluster-type metastases. The CCL22-CCR4 axis contributes to this selective infiltration process. [ABSTRACT FROM AUTHOR]

Hepatitis B virus (HBV) quasispecies contain a large number of variants that serve as a reservoir for viral selection under antiviral treatment and the immune response, leading to the acute exacerbation and subsequent development of liver failure. However, there is no clear experimental evidence for a significant role of HBV quasispecies in viral pathogenesis. In the present study, HBV sequences were amplified from a patient with severe liver disease and used for construction of HBV replication-competent plasmids. Western blotting, enzyme-linked immunosorbent assay (ELISA), and immunofluorescence staining were performed to analyze the expression, secretion, and subcellular localization of viral proteins in vitro. Viral replication intermediates were detected by Southern blotting. HBV gene expression and replication and the induction of specific immune responses in an HBV hydrodynamic injection (HI) mouse model were investigated. The results demonstrated that two naturally occurring HBV variants, SH and SH-DPS, were identified. The variant SH-DPS expressed only a nonexportable hepatitis B virus surface antigen (HBsAg) with abnormal intracellular accumulation. The coexistence of the HBV variants at a ratio of 1 to 4 (SH to SH-DPS) increased HBV replication. Significantly stronger intrahepatic cytotoxic T lymphocyte (CTL) responses and antibody responses specific to HBsAg were induced in mice by the HBV variants when coapplied by HI. These findings uncovered an unexpected aspect of HBV quasispecies: the coexistence of different variants can significantly modulate specific host immune responses, representing a novel mechanism for the immunopathogenesis of HBV infection. [ABSTRACT FROM AUTHOR]

Di-(2-ethylhexyl) adipate (DEHA) and phthalates are commonly used as plasticizers to soften polyvinyl chloride products. Because both DEHA and certain phthalates have been identified as priority chemicals for assessment of human health risk under the Government of Canada's Chemicals Management Plan, a comprehensive targeted survey was conducted to investigate the occurrence of DEHA and eight phthalates (di-methyl phthalate, di-ethyl phthalate, di-n-butyl phthalate, di-iso-butyl phthalate, butyl benzyl phthalate, di-n-hexyl phthalate, d-(2-ethylhexyl) phthalate, and di-n-octyl phthalate) in a total of 118 samples of meat (beef, pork, and chicken), fish, and cheese packaged mostly in cling films. The eight phthalates were not detected in any of the food packaging, but DEHA was detected in most of the cling films, indicating that although DEHA-plasticized films (e.g., polyvinyl chloride film) are currently being used by most grocery stores, nonplasticized cling films such as polyethylene film, are also being used by some stores. DEHA was not detected in any of the 10 cheese samples packaged in nonplasticized rigid plastics but was detected in all 30 cheese samples packaged in DEHA-plasticized cling films at levels from 0.71 to 879 µg/g, with an average of 203 µg/g. Only DEHA was detected in the beef, pork, chicken, and fish samples packaged in DEHA-plasticized cling films but at considerably lower levels than those found in cheese, with averages of 6.3, 9.1, 2.5, and 5.9 µg/g, respectively. Among the eight phthalates, only di-(2-ethylhexyl) phthalate (DEHP) was detected in a few cheese samples at levels from 0.29 to 15 µg/g, with an average of 2.8 µg/g; these levels were very likely due to environmental contamination. Levels of DEHA found in most of the cheese samples from this study are above the European specific migration limit of 18 mg/kg for DEHA in food or food simulants, and levels of phthalates (i.e., DEHP) were low. [ABSTRACT FROM AUTHOR]

Polyvinyl chloride (PVC) food-wrapping films plasticized with di-(2-ethylhexyl) adipate (DEHA) are commonly used by grocery slores in Canada to rewrap meat, poultry, fish, cheese, and other foods. DEHA was assessed as part of the Government of Canada's Chemicals Management Plan. The main source of exposure for most age groups was expected to be food. Although the margin of exposure from food and beverages is considered to be adequately protective, the Government of Canada committed to performing targeted surveys of DEHA in foods and food packaging materials to better define Canadian exposure to DEHA through dietary intake. In order to determine whether more-comprehensive targeted surveys on DEHA in foods should be conducted, 26 food composite samples from the 2011 Canadian total diet study were selected and analyzed for DEHA using a method based on solvent and dispersive solid-phase extraction and gas chromatography-mass spectrometry. These 26 food composites include cheese, meat, poultry, fish, and fast foods, and PVC films were likely used in packaging the individual foods used to make the composites. DEHA was detected in most of the meat, poultry, and fish composite samples, with the highest concentration found in ground beef (11 µg/g), followed by beef steak (9.9 µg/g), freshwater fish (7.8 µg/g), poultry liver pâté (7.4 µg/g), fresh pork (6.9 µg/g), cold cuts and luncheon meats (2.8 µg/g), veal cutlets (2.1 µg/g), roast beef (1.3 µg/g), lamb (1.2 µg/g), and organ meats (0.20 µg/g). Targeted surveys should be conducted to investigate the presence of DEHA in various foods packaged with PVC films in more detail and provide updated occurrence data for accurate human exposure assessment. [ABSTRACT FROM AUTHOR]

• Stepwise carrier concentration optimization of Bi 2 GeTe 4 thermoelectric materials. • Ge vacancy-engineering transfer Bi 2 GeTe 4 into highly degenerated semiconductor. • Carrier concentration optimization leads to high power factor of 4.2 μW cm−1 K−2. • Approaching a record-high zT value of ∼ 0.22 at 423 K in Bi 2 Ge 1.45 Te 4. Bi 2 GeTe 4 is a promising near room-temperature thermoelectric candidate with a low lattice thermal conductivity. Carrier concentration of intrinsic Bi 2 GeTe 4 changes dramatically with tiny Ge content adjustment, leading to a challenge in carrier concentration optimization. To overcome this challenge, we firstly introduce excessive Ge into Bi 2 GeTe 4 to shift the Fermi level deep into the conduction band and transfer Bi 2 GeTe 4 into a highly degenerate n-type semiconductor. Secondly, the embedded p-type Bi 2 Ge 2 Te 5 secondary phase induces further optimization of the Fermi level and carrier concentration. Finally, the power factor of the as-synthesized Bi 2 GeTe 4 -based material is significantly increased from ∼ 0.08 μW cm−1 K−2 to ∼ 4.2 μW cm−1 K−2 at 423 K when increasing the nominal Ge content (x) of Bi 2 Ge x Te 4 from 1 to 1.45. Correspondingly, a high figure-of-merit of ∼ 0.22 at 423 K is achieved in Bi 2 GeTe 4 -based thermoelectric materials. This result indicates our viable stepwise strategy can be used to optimize carrier concentration and achieve high thermoelectric performance of the n-type Bi 2 GeTe 4. [ABSTRACT FROM AUTHOR]

Pt-based nanoparticles (NPs) have been widely used in catalysis. However, this suffers from aggregation and/or sintering at working conditions. We demonstrate a robust strategy for stabilizing PtCo NPs under high temperature with strong interaction between M-N-C and PtCo NPs with Pt-M-N coordination, namely, "atom glue." Such atom glue for stabilizing Pt-based NPs can be extended to Zn, Mn, Fe, Ni, Co, and Cu, being a versatile strategy for stabilizing PtCo NPs, which substantially promotes the performance toward oxygen reduction reaction (ORR) and fuel cell. Impressively, the mass activity (MA) reaches 2.99 A mgPt-1 for ORR over g-Zn-N-C/PtCo, and 79.3% of the initial MA is maintained after 90K cycles in fuel cell. This work provides a versatile strategy for stabilizing Pt-based NPs via atom glue, which is likely to spark widespread interest across various fields. [ABSTRACT FROM AUTHOR]

A method based on isotope dilution headspace solid-phase microextraction, followed by gas chromatography and mass spectrometry, was developed for the determination of naphthalene in foods. Optimum method sensitivity was achieved by the addition of NaC1 in water at saturation and with the sample solution incubated at 30°C for 15 min. The method had good repeatability, with relative standard deviations of 3.5 and 1.5% at 5 and 30 ng/ml, respectively. This method was used to determine naphthalene in 159 food composite samples collected from the 2011 Canadian Total Diet Study. Naphthalene was detected in 93 (58.9%) food composite samples, mostly in products of meat and cereal, fast food, and miscellaneous foods. Among the 93 samples, only 51 (54.8%) samples were found to contain naphthalene at levels above 1 ng/g, with a maximum of 35 ng/g found in the herbs and spices composite sample. Method detection limits, estimated for each one of the food composite samples by using the lower-abundance ion m/z 127, varied considerably because of the matrix effect, ranging from as low as 0.0022 ng/g for water to as high as 16 ng/g for fatty sample, with an average of 1.6 ng/g. [ABSTRACT FROM AUTHOR]

Adiabatic wavelength conversion is experimentally demonstrated at a single photon power-level using an integrated silicon ring resonator. This approach allows conversion of a photon to arbitrary wavelengths with no energy or phase matching constraints. The conversion is inherently low-noise and efficient with greater than 10% conversion efficiencies for wavelength changes up to 0.5?nm, more than twenty times the resonators line-width. The observed wavelength change and efficiency agrees well with theory and bright coherent light demonstrations. These results will enable integrated quantum optical wavelength conversion for application ranging from wavelength-multiplexed quantum networks to frequency bin entanglement. [ABSTRACT FROM AUTHOR]

The associations between neuroticism, employees' preference of emotional labor strategies, and job feedback were investigated using a cross-sectional self-report questionnaire survey. The mediating effect of job feedback was tested using regression analysis with a sample of 168 nurses. Results showed that neuroticism was associated more with surface acting, and less with both deep acting and job feedback; job feedback fully mediated the relationship between neuroticism and deep acting. Implications and directions for future research and practices are suggested. [ABSTRACT FROM AUTHOR]

Based on the full cavitation model which adopts homogeneous flow supposition and considering the compressibility effect on cavitation flow to modify the re-normalization group ??-?? turbulence model by the density function, a computational model is developed to simulate cavitation flow of a centrifugal pump at low flow rate. The Navier- Stokes equation is solved with the SIMPLEC algorithm. The calculated curves of net positive suction head available (NPSHa) HNPSHa agree well with the experimental data. The critical point of cavitation in centrifugal pump can be predicted precisely, and the NPSH critical values derived from simulation are consistent with the experimental data. Thus the veracity and reliability of this computational model are verified. Based on the result of numerical simulation, the distribution of vapor volume fraction in the impeller and pressure at the impeller inlet are analyzed. Cavities first appear on the suction side of the blade head near the front shroud. A large number of cavities block the impeller channels, which leads to the sudden drop of head at the cavitation critical point. With the reduction of NPSHa, the distribution of pressure at the impeller inlet is more uniform. [ABSTRACT FROM AUTHOR]

Context: Lung cancer, the most common type of cancer, has a high mortality rate. Cucurbitacin B (CuB), a natural compound extracted from Cucurbitaceae plants, has antitumor effects. Objective: We investigated the role of CuB on lung cancer and its potential mechanisms. Materials and methods: A549 cells were treated with 0.1, 0.3, 0.6, and 0.9 lM CuB for 12, 24, and 48 h or untreated. Gene and protein levels were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting. Enzyme-linked immunosorbent assay (ELISA) detected inflammatory factors levels (TNF-a and IL-10). 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), flow cytometry, and colony formation assays measured cell viability, apoptosis, and proliferation. The interaction between miR-let-7c and long non-coding RNA X inactive-specific transcript (XIST) or interleukin-6 (IL-6) was verified by dual-luciferase reporter assays. Results: CuB treatment inhibited the proliferation of lung cancer cells and promoted cell apoptosis, and increased the expression of Bax and cleaved caspase3, decreased cyclin B1 and Bcl-2 expression. CuB suppressed XIST and IL-6 expression, and enhanced miR-let-7c expression. XIST silencing enhanced the inhibitory effect of CuB on cell proliferation and the promotion effect on apoptosis via upregulating miR-let-7c. Moreover, XIST targeted miR-let-7c to activate the IL-6/STAT axis. MiR-let-7c overexpression enhanced the regulatory effect of CuB on proliferation and apoptosis via suppressing the IL-6/STAT3 pathway. Discussion and conclusion: CuB regulated cell proliferation and apoptosis by inhibiting the XIST/miR-let-7c/IL-6/STAT3 axis in lung cancer. These findings indicate CuB may have the possibility of clinical application in lung cancer treatment. [ABSTRACT FROM AUTHOR]

Interactions between Bacillus anthracis (B. anthracis) and host cells are of particular interest given the implications of anthrax as a biological weapon. Inhaled B. anthracis endospores encounter alveolar macrophages as the first line of defense in the innate immune response. Yet, the consequences of this interaction remain unclear. We have demonstrated that B. anthracis uses arginase, inherent in the endospores, to reduce the ability of macrophages to produce nitric oxide (NO) from inducible nitric oxide synthase (NOS2) by competing for l-arginine, producing l-ornithine at the expense of NO. In the current study, we used genetically engineered B. anthracis endospores to evaluate the contribution of germination and the lethal toxin (LT) in mediating signaling pathways responsible for the induction of NOS2 and ornithine decarboxylase (ODC), which is the rate-limiting enzyme in the conversion of l-ornithine into polyamines. We found that induction of NOS2 and ODC expression in macrophages exposed to B. anthracis occurs through the activation of p38 and ERK1/2 MAP kinases, respectively. Optimal induction of NOS2 was observed following exposure to germination-competent endospores, whereas ODC induction occurred irrespective of the endospores' germination capabilities and was more prominent in macrophages exposed to endospores lacking LT. Our findings suggest that activation of kinase signaling cascades that determine macrophage defense responses against B. anthracis infection occurs through distinct mechanisms. [ABSTRACT FROM AUTHOR]

variety of ordered mesoporous carbons (OMCs) were synthesized using ordered mesoporous silicas (OMSs) as hard templates and the mesophase pitch (MP) as a carbon precursor. The synthesis included the mixing of OMS with MP, the infiltration of OMS with MP at 450–550 °C and the carbonization of MP in OMS/MP composite followed by the dissolution of the OMS template. OMCs with structures of two-dimensional hexagonal arrays of nanorods and three-dimensional arrays of nanospheres were obtained through the replication of silica templates, including large-pore SBA-15, KIT-6, large-pore FDU-12 and SBA-16. In particular, 2-D hexagonal array of carbon nanorods (CMK-3 carbon) with (100) interplanar spacing of ∼13 nm as well as an array of carbon nanospheres arranged in the face-centered cubic structure with the unit-cell parameter of 33 nm were successfully prepared. The specific surface areas of the resulting carbons were up to 400 m/g, and the total pore volumes were up to 0.43 cm/g, with the highest values achieved when the MP infiltration temperature was 500 °C. The OMCs exhibited narrow mesopore size distributions. As inferred from XRD, the frameworks of OMCs featured semi-graphitic structures even though moderate carbonization temperature (850 °C) was employed. [ABSTRACT FROM AUTHOR]

An equivalent circuit for a hysteresis motor (HM) is established in this paper, of which the electrical parameters can be directly calculated for motor analysis. The circuit is based on the parallelogram hysteresis model (PHM), which is often used in the analysis of electric machines, including the HMs and the permanent magnet motors. In this paper, a significant variable (Br) of the PHM developed by Copeland and Slemon (CSPM) is first modified, which makes the major loop area of the B–H parallelogram and that of the B–H rectangular loop theoretically equal. Then, the equivalent circuit of an HM is set up. To obtain the parameters in the equivalent circuit, the corresponding ellipse model of the modified CSPM is derived by Fourier transform. Finally, a 30-HP written pole machine is analyzed and its rated operation point is obtained from the equivalent circuit. The test data validate the equivalent circuit and the calculations. The method presented in this paper is proved to be useful in the design of HMs as well as written pole machines. [ABSTRACT FROM PUBLISHER]

Acute (0, 0.1, 0.2, 0.4, 0.8, 1.6 mg Cu/L) and chronic (0, 0.02, 0.04, 0.06, 0.08, 0.10, 0.12 mg Cu/L) toxicity tests of Cu with embryonic and larval red sea bream, Pagrus major, were carried out to investigate their biological responses to Cu exposure in static water at 18 ± 1°C (dissolved organic carbon, 1.8 ± 0.65 mg C/L; hardness, 6,183 ± 360 mg CaCO3/L; salinity, 33 ± 1‰). The 24- and 48-h LC50 (median lethal concentration) values of Cu for embryos were 0.23 and 0.15 mg/L, whereas the 48-, 72-, and 96-h LC50 values for larvae were 0.52, 0.19, and 0.13 mg/L, respectively, suggesting that embryos were more sensitive to Cu toxicity than larvae. Copper exposures at ≥0.06 mg concentrations caused low hatching success, a delay in the time to hatching of embryos, and reductions in the growth and yolk absorption of the larvae, whereas high mortality and morphological malformations occurred in the embryos and larvae at ≥0.08 mg/L concentrations. Copper concentration did not significantly affect the heart rate of the embryos, but it significantly decreased the heart rate of the newly hatched larvae when the Cu concentration was ≥0.08 mg/L, suggesting that Cu at high concentrations could induce heartbeat disturbances in red sea bream more easily at the larval stage than at the embryonic stage. Hatching success, time to hatching, growth rate, morphological abnormality, yolk absorption, and heart rate were Cu concentration-dependent and could be effective endpoints for evaluating Cu toxicity to the early life stages of red sea bream in nature. Environ. Toxicol. Chem. 2010;29:2044–2052. © 2010 SETAC [ABSTRACT FROM AUTHOR]

Although migration from can coatings is likely the source of bisphenol A (BPA) for the canned soft drink products with relatively high BPA concentrations, questions have been raised concerning the exact sources of BPA for those canned soft drink products with low BPA concentrations. Information is also needed for BPA concentrations in canned beer products to conduct proper exposure assessment for BPA under the Government of Canada's Chemicals Management Plan. In this work, 22 soft drink samples and 16 beer samples in both cans and plastic and/or glass bottles were analyzed for BPA. BPA was not detected in any of the soft drink samples in either plastic or glass bottles except for one product with a BPA concentration (0.018 µg/liter) close to the limit of quantification (0.015 µg/liter). BPA was detected in all of the corresponding soft drink products in cans, indicating that migration from can coatings is the likely source for BPA in canned products. Because considerable interference with ions m/z 213 and m/z 228 from sample matrices was observed for all beer samples, BPA concentrations in beer samples were measured using the ion m/z 270 instead. BPA was detected in only one of the seven beer products in glass bottles (0.054 µg/liter) but was detected in all corresponding beer samples in cans at low concentrations ranging from 0.081 to 0.54 µg/liter, indicating that migration from can coatings is likely the source of BPA in canned beer products. [ABSTRACT FROM AUTHOR]

A method based on solid phase extraction followed by derivatization and gas chromatography-mass spectrometry analysis was validated for the determination of bisphenol A (BPA) in canned food products. This method was used to analyze 78 canned food products for BPA. Concentrations of BPA in canned food products differed considerably among food types, but all were below the specific migration limit of 0.6 mg/kg set by the European Commission Directive for BPA in food or food simulants. Canned tuna products had the highest BPA concentrations in general, with mean and maximum values of 137 and 534 ng/g, respectively. BPA concentrations in the condensed soup products were considerably higher than those in the ready-to-serve soup products, with mean and maximum values of 105 ,and 189 ng/g, respectively, for the condensed soups and 15 and 34 ng/g, respectively, for file ready-to-serve soups. BPA concentrations in canned vegetable products were relatively low; about 60% of the products had BPA concentrations of less than 10 ng/g. Canned tomato paste products had lower BPA concentrations than did canned pure tomato products. The mean and maximum BPA concentrations were 1.1 and 2.1 n/g, respectively, for tomato paste products and 9.3 and 23 rig/g, respectively, for the pure tomato products. [ABSTRACT FROM AUTHOR]

Ce0.8Zr0.2O2 solid solutions were prepared by three different methods, namely, surfactant-assisted, co-precipitation, and sol–gel methods, and were used as supports of CuO nanocatalysts by the deposition-precipitation (DP) method. The prepared supports and catalysts were characterized by using XRD, N2 adsorption, TEM, and H2-TPR techniques. The influence of preparation methods on the low-temperature carbon monoxide oxidation activity of these CuO/Ce0.8Zr0.2O2 catalysts was investigated comparatively by using a microreactor-GC system. The catalyst prepared by surfactant-assisted method is more active for low-temperature CO oxidation than the ones prepared by the co-precipitation and sol–gel methods. The support and catalysts prepared by surfactant-assisted method possess mesoporous framework, nanoscale particle size, and high surface area, improving the synergistic effect between CuO species and support, which is beneficial for enhancing the catalytic performance of low-temperature CO oxidation. [ABSTRACT FROM AUTHOR]

Hierarchically mesoporous–macroporous titanium dioxide (MMTD) was synthesized by the hydrolysis of tetrabutyl titanate in the absence of surfactant and autoclaving at 60 °C, which exhibits a porous hierarchy of wormhole-like mesostructure in the framework of macrochannels. Different contents of CuO nanoparticles were supported on the MMTD by a deposition–precipitation (DP) method, retaining the high surface areas and hierarchical porosity. The prepared MMTD support and the resulting CuO/MMTD nanocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2 adsorption analysis, temperature-programmed reduction (TPR), and X-ray photoelectron spectroscopy (XPS) techniques. Their catalytic behavior for low-temperature CO oxidation was studied by using a microreactor–GC system, and the CuO/MMTD catalyst with 8 wt% CuO content and calcined at 400 °C was found to have the highest catalytic activity. The catalytic activity depended on the CuO loading amount, the precalcination temperature, the meso–macroporous framework, the surface area, and the particle size of the CuO/MMTD catalysts. [ABSTRACT FROM AUTHOR]

Information on migration of bisphenol A (BPA) from can coatings to foods during storage at room temperature is very limited, and the conclusions from the available studies are not always consistent. To investigate the effect of storage time on BPA migration from can coatings to liquid infant formula at room temperature, samples of 21 canned liquid infant formula products from different cans but the same lot as those analyzed for BPA previously were analyzed for BPA again after storage at room temperature for 10 months. Additional migration of BPA from can coatings to liquid formula during the 10-month storage period at room temperature was observed for 9 of the 21 products, with increases in BPA levels ranging from 29.8 to 110%. Significant differences between the 2007 and 2008 results (P = 0.026) were observed for only one brand of product, which had the lowest BPA levels in the 2007 survey. The BPA levels in the milk-based formula products analyzed in 2008 (mean, 6.8 ng/g) were significantly higher (P = 0.00023) than those in the milk-based formula products analyzed in 2007 (mean, 5.0 ng/g), whereas the differences in BPA levels between the soya-based formula products analyzed in 2008 (mean, 5.3 ng/g) and those analyzed in 2007 (mean, 5.8 ng/g) were not significant (P = 0.097). No obvious correlation between the product expiration date and the level of BPA migration from can coatings was observed. [ABSTRACT FROM AUTHOR]

Abstract  Poly(ethylene oxide)-poly(methyl acrylate) diblock copolymers with narrow molecular weight distributions were synthesized using atom transfer radical polymerization. The copolymers were used as micellar templates for the synthesis of mesoporous silicas. The products were characterized using small-angle X-ray scattering, transmission electron microscopy (TEM) and nitrogen adsorption. The obtained silicas exhibited two-dimensional hexagonal structures of cylindrical mesopores, and thus can be classified as SBA-15 silicas. In some cases, the size of ordered domains was very small. The (100) interplanar spacings were 13–17 nm, depending on the size of the diblock copolymer used and on the synthesis conditions. Nitrogen adsorption showed that the silicas exhibited specific surface areas of 350–800 m2 g−1, pore volumes ∼1 cm3 g−1, and narrow pore size distributions. The BJH (nominal) pore diameters were up to ∼20 nm, but actual diameters of cylindrical pores are expected to be somewhat smaller. In many cases, the mesopores exhibited constrictions. [ABSTRACT FROM AUTHOR]

It is proposed herein that in order to obtain ultralarge-pore ordered mesoporous silicas using surfactant-templated synthesis with micelle expanders, one should select a micelle swelling agent with a moderate swelling ability to achieve an appreciable pore diameter enlargement while avoiding the formation of heterogeneous and/or poorly defined nanostructure. It is suggested to identify viable swelling agents based on the extent of solubilization of swelling agents in micellar solutions. On the basis of this reasoning, cyclohexane, 1,3,5-triethylbenzene and 1,3,5-triisopropylbenzene (TIPB) were selected for the synthesis of large-pore SBA-15 silicas with two-dimensional (2-D) hexagonal structures of cylindrical mesopores. SBA-15 with pore diameter tunable from 10 to 26 nm was obtained at initial synthesis temperature 12.25−20 °C using Pluronic P123 triblock copolymer as a micellar template and triisopropylbenzene as a micelle expander. Structures of the materials were characterized using small-angle X-ray scattering, TEM, and gas adsorption. The lowering of the initial synthesis temperature with adjustment of the amount of TIPB afforded pore diameters up to 26 nm (BJH pore diameters up to 34 nm) and (100) interplanar spacings up to 26 nm for 2-D hexagonal structure. As the initial synthesis temperature was lowered further, the pore diameter increased further (to ∼50 nm) with appreciable retention of cylindrical pore shape, but the pore structure became heterogeneous. The present approach makes silicas with 2D hexagonally ordered cylindrical pores of diameter up to 26 nm readily available and opens new opportunities in the synthesis of materials with other pore geometries and framework types. [ABSTRACT FROM AUTHOR]

In this paper, we study the thermal entanglement in a two-qubit Heisenberg XYZ system with different Dzyaloshinskii–Moriya (DM) couplings. We show that different DM coupling parameters have different influences on the entanglement and the critical temperature. In addition, we find that when Ji (i-component spin coupling interaction) is the largest spin coupling coefficient, Di (i-component DM interaction) is the most efficient DM control parameter, which can be obtained by adjusting the direction of DM interaction. [ABSTRACT FROM AUTHOR]