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This paper presents a framework for automated optimization of double-heater convective PCR (DH-cPCR) devices by developing a computational fluid dynamics (CFD) simulation database and artificial neural network (ANN) model. The optimization parameter space that includes the capillary tube geometries and the heater sizes of DH-cPCR is established, and a database consisting of nearly 10,000 CFD simulations is constructed. The database is then used to train a two-stage ANN models that select practically relevant data for modeling and predict PCR device performance. The trained ANN model is then combined with the gradient-based and the heuristics optimization approaches to search for optimal device configuration that possesses the shortest DNA doubling time. The entire design process including model meshing and configuration, parallel CFD computation, database organization, and ANN training and utilization is fully automated. Case studies confirm that the proposed framework can successfully find the optimal device configuration with an error of less than 0.3 s, and hence, representing a cost-effective and rapid solution of DH-cPCR device design.

Parallel restoration is an efficient way to speed up the restoration process after a wide‐area outage or a complete blackout of a power system. To implement efficient parallel restoration, an appropriate network partitioning method is necessary. Given this background, a two‐step network partitioning strategy for parallel power system restoration is presented. In order to minimise the restoration time of generating units, a grouping model for non‐black‐start units is developed first. Based on the graph theory, a power network partitioning model is presented with the objectives of minimising the number of the interconnected lines and maximising the electrical distance of the interconnected lines among different restoration subsystems. The well‐established AMPL/CPLEX is employed to solve the developed optimisation models. Finally, the IEEE New England 10‐unit 39‐bus system and a part of Zhejiang provincial power system in China are employed to illustrate the feasibility and effectiveness of the developed models. [ABSTRACT FROM AUTHOR]

An LC/MS/MS-based method was developed for the determination of individual bile acids (BA) and their conjugates in porcine bile samples. The C18-based solid-phase extraction (SPE) procedure was optimized so that all 19 target BA and their glycine and taurine conjugates were collected with high recoveries for standards (89.1-100.2 %). Following this, all 19 compounds were separated and quantified in a single 12 min chromatographic run. The method was validated in terms of linearity, sensitivity, accuracy, precision, and recovery. An LOD in the low ppb range with measured precisions in the range of 0.5-9.3 % was achieved. The recoveries for all of the 19 analytes in bile samples were all >80 %. The validated method was successfully applied to the profiling of BA and their conjugates in the bile from piglets treated with exogenous glucagon-like peptide-2 (GLP-2) in a preclinical model of neonatal parenteral nutrition-associated liver disease (PNALD). The method developed is rapid and could be easily implemented for routine analysis of BA and their conjugates in other biofluids or tissues. [ABSTRACT FROM AUTHOR]

Exploring low-cost and earth-abundant oxygen reduction reaction (ORR) electrocatalyst is essential for fuel cells and metal-air batteries. Among them, non-metal nanocarbon with multiple advantages of low cost, abundance, high conductivity, good durability, and competitive activity has attracted intense interest in recent years. The enhanced ORR activities of the nanocarbons are normally thought to originate from heteroatom (e.g., N, B, P, or S) doping or various induced defects. However, in practice, carbon-based materials usually contain both dopants and defects. In this regard, in terms of the co-engineering of heteroatom doping and defect inducing, we present an overview of recent advances in developing non-metal carbon-based electrocatalysts for the ORR. The characteristics, ORR performance, and the related mechanism of these functionalized nanocarbons by heteroatom doping, defect inducing, and in particular their synergistic promotion effect are emphatically analyzed and discussed. Finally, the current issues and perspectives in developing carbon-based electrocatalysts from both of heteroatom doping and defect engineering are proposed. This review will be beneficial for the rational design and manufacturing of highly efficient carbon-based materials for electrocatalysis.

It seems to be generally acceptable that recrystallization-controlled rolling is used to produce ultra-heavy plate. However, due to large thickness of the slab, it is difficult to make enough plastic deformation, occurred in central layer. This leads to coarse grain in the center and heterogeneity of property along thickness direction. In this study, the effect of temperature gradient on the strain and austenite grain recrystallization was investigated during ultra-heavy plate rolling by means of FEM and experiments. Results indicate that gradient temperature rolling is better for increasing strain and enhancing austenite recrystallization in the center of ultra-heavy plate. [ABSTRACT FROM PUBLISHER]

The matching quality between the femoral head prosthesis and the acetabulum plays an important role in the operative treatment of the artificial femoral head replacement. In order to obtain a more accurate model of the femoral head prosthesis for the target sufferer, an improved individualized modeling system was presented in this paper. It was different from our previous system based on the sphere fitting method. This new system could reconstruct a more accurate ellipsoid model of the femoral head for the target sufferer. It could recover the necrotic femoral heads into the satisfactory models. These models could well match with the acetabulums. This improved system afforded a theoretical model for the accurate surgical position fixing in the orthopaedic clinic. And this system also provided an innovative practical means for the individualized modeling and manufacture of the artificial femoral head prosthesis. [ABSTRACT FROM AUTHOR]

Heat-affected zones (HAZs) were simulated with a peak temperature of 1320 °C at different welding heat inputs for a Cr–Mo low-alloy steel. The ductile-to-brittle transition temperature (DBTT) of the HAZs increased with increasing heat input. When 0.05 wt.% Sb was added to the steel, the DBTTs of the HAZs became 1 and 10 °C higher than those for the undoped steel at heat inputs of 36 and 60 kJ/cm, respectively. Sb segregation to austenite grain boundaries during thermal cycling was found to be mainly responsible for the DBTT increase. [ABSTRACT FROM PUBLISHER]

Microtubules are considered as important targets of anticancer therapy. Podophyllotoxin and its structural derivative are major microtubule-interfering agents with potent anticancer activity. In this study, we reported the anticancer effects of 10 representative podophyllotoxin derivatives on a panel of four human cancer cell lines. Deoxypodophyllotoxin ( 6b) and β-apopicropodophyllotoxin ( 6g) elicited strong antiproliferative effects ( IC50) at a range of 0.0073-0.14 μ m. Direct tubulin depolymerization assay in vitro was also performed. Results showed that that the two compounds can inhibit microtubule polymerization. Experimental measurements were also supported by molecular dynamic simulations, which showed that the two active compounds formed interactions with the colchicine-binding site of the tubulin protein. Our results helped us understand the nature of tubulin binding and determine the core design of a new series of potent inhibitors of tubulin polymerization. [ABSTRACT FROM AUTHOR]

An author index for the June 2013 issue of the journal "Vox Sanguinis" is presented.

In field conditions, seven fertilization treatments were applied by randomized design with three replications. At a late growth stage of Chinese cabbage, the plant leaf chlorophyll content, photosynthetic rate (Pn), transpiration rate (Tr), and stomatal conductance (Gs) significantly increased upon the three fertilization modes, which were synthetic and organic fertilizers combined (SOF), synthetic fertilizer and dicyandiamide combined (SFD), and organic fertilizer inoculated live earthworms (OFE) than the other treatments. Organic fertilizer application significantly improved superoxide dismutase (SOD), Peroxidase (POD) and Catalase (CAT) activities and decreased malondialdehyde (MDA) accumulation, especially in the organic fertilizer inoculated live earthworms treatment. The SOF, SFD and OFE treatments improved the plant yield by 40.5%, 38.0% and 36.1% than the synthetic fertilizer applied alone treatment (SFB) and by 23.4%, 21.1% and 19.6% than the synthetic fertilizer in a split application treatment (SFT). Compared to single applied synthetic fertilizer, the OFE treatment significantly reduced nitrate content, and also improved sugar-acid ratio and soluble sugar and Vc content in the heads of the plant at the harvest stage. All this suggests the OFE treatment is a healthy, sustainable and environmentally friendly fertilization way for the Chinese cabbage production in north of China. [ABSTRACT FROM AUTHOR]

The cytotoxic properties of four synthesized coumarin derivatives containing 4-bromophenyl or anthracene moieties against the human hepatocellular carcinoma cell lines (HepG-2) were investigated in vitro by use of the sulforhodamine B (SRB) assay. The four coumarin derivatives are 3-(4-bromophenyl)-benzo[5,6]coumarin ( 1a), 3-(4-bromophenyl)-7-( N, N-diethylamino)coumarin ( 1b), 3-(4-(anthracen-10-yl)phenyl)-benzo[5,6]coumarin ( 2a), and 3-(4-(anthracen-10-yl)phenyl)-7-( N, N-diethylamino)coumarin ( 2b). The preliminary results indicate that 1a, 2a, and 2b have significant cytotoxicity against HepG-2 whereas 1b has a growth-promotion effect. [ABSTRACT FROM AUTHOR]

The aim of this article is to briefly review the progress made over the past few years in the theoretical description of the intrinsic charge-transport properties of organic molecular crystals. We first discuss the state-of-the-art methodologies used in the derivation of the electronic coupling and electron-phonon coupling constants. We illustrate the application of these techniques to two classes of semiconductors of interest for crystal-based organic electronics: crystals consisting of a single molecular building block, such as oligoacenes and their derivatives, and bimolecular crystals consisting of donor and acceptor compounds. After a brief overview of recent developments in the polaron modeling of the electronic and electrical properties of these systems, we examine the impact that the interplay between electronic interactions and various electron-phonon mechanisms has on the temperature dependence of the charge-carrier mobility. [ABSTRACT FROM PUBLISHER]

The 25-year history and development of an ultra-small-angle X-ray scattering (USAXS) instrument dedicated to serving materials research is presented and discussed. The instrument's successful track record is attributed to three factors. The first, and surely the most important, is that all development has been driven by scientific research directions and opportunities. Second, the USAXS instrument is a core capability rather than an add-on facility, with measurement capability from micrometers to nanometers, which is precisely the size range where microstructures determine physical properties. The third is that the instrument's range of capabilities has continually expanded, now including 2D collimation, imaging, and dynamics. And finally, USAXS has enjoyed the benefit of a management structure that has consistently appreciated the unique experimental measurement capabilities that USAXS delivers. [ABSTRACT FROM AUTHOR]

Several parameters of the fabrication process of inverted polymer bulk heterojunction solar cells based on titanium oxide as an electron selective layer and molybdenum oxide as a hole selective layer were tested in order to achieve efficient organic photovoltaic solar cells. Thermal annealing treatment is a common process to achieve optimum morphology, but it proved to be damageable for the performance of this kind of inverted solar cells. We demonstrate using Auger analysis combined with argon etching that diffusion of species occurs from the MoO3/Ag top layers into the active layer upon thermal annealing. In order to achieve efficient devices, the morphology of the bulk heterojunction was then manipulated using the solvent annealing technique as an alternative to thermal annealing. The influence of the MoO3 thickness was studied on inverted, as well as direct, structure. It appeared that only 1 nm-thick MoO3 is enough to exhibit highly efficient devices (PCE = 3.8%) and that increasing the thickness up to 15 nm does not change the device performance. [ABSTRACT FROM AUTHOR]

An author index for the periodical is presented.

Light and X-ray scattering are used to examine the structure of two commercial precipitated silicas (Zeosil 1165 and Ultrasil 7005) and one developmental precipitated silica, Dimosil 288. All three products have a four-level hierarchical structure consisting of primary particles, aggregates, hard agglomerates and soft agglomerates, with Dimosil 288 showing the clearest evidence of the four structural levels. The impact of sonication and drying protocol was explored by light scattering for Dimosil 288. With the exception of the large-scale soft agglomerates, all the structural levels are robust under sonication of aqueous suspensions. Sonication breaks down soft agglomerates leaving hard structures approximately 11 μm in radius-of-gyration. Drying plays a critical role in hardening the soft agglomerates. If the product is never dried, sonication reduces the agglomerate size to 3.5 μm, which is identified as the size of the hard agglomerate. Although agglomerates larger than 3.5 μm are present in the never-dried product, they are friable. Large-scale agglomerates are marginally more robust when dried at 150 °C compared to room temperature drying. Given the similarity of mechanical properties of rubbers filled with these silicas, it appears that the four-level structure with friable large-scale soft agglomerates is a characteristic of highly dispersing silica products. [ABSTRACT FROM AUTHOR]

The article discusses the angle resolved photoemission spectroscopy (ARPES) studies on the iron-pnictides and iron-chalcogenides superconductors. It explores the multi-band and multi-orbital nature of the electronic structure, the mechanism of the structural and magnetic transitions and the superconducting gap. It is found that the low-lying electronic structures of iron-based superconductors are characterized by a multi-band and multi-orbital nature. distributions.

Understanding the pattern of phytoplankton and their dependence on water quality variables, can help the management of eutrophic lakes. The aim of this study was to determine water quality and environmental factors associated with cyanobacteria dominance and microcystin production in Qingshan Lake, a subtropical lake located in the headwater of the Taihu watershed, China. Water samples collected monthly from 10 study sites in Qingshan Lake were analyzed for the species distributions of freshwater algae and physico-chemical parameters including total nitrogen (TN), ammonia (NH-N), nitrate (NO-N), total phosphorus (TP), and chlorophyll a (Chl-a) from June, 2008 to May, 2009. Qingshan Lake was found to be eutrophic, based on the calculated trophic state index (TSI). The average TN of 4.33 mg/L during the study period exceeded the Surface Water Quality Standards of China. TP was significantly correlated with relative abundance of cyanobacteria and Microcystis biovolume, indicating its important role in regulating cyanobacteria. Microcystis, Anabaena, and Oscillatoria were dominant cyanobacteria in Qingshan Lake from June to November, 2008. Cyanobacteria dominance was regulated by water temperature and TP. Principal component analysis further indicated that microcystin production was most affected by water temperature, TP, and cyanobacteria biomass. Results suggest that the control of TP in summer can mitigate cyanobacteria dominance and microcystin production in Qingshan Lake, and close monitoring should be undertaken in summer. [ABSTRACT FROM AUTHOR]

In recent years, organic semiconductors have emerged as a promising and, in some situations, viable commercial alternative to traditional inorganic materials such as silicon. Organic-based light emitting diodes, photovoltaic devices, photodetectors, and transistors have attracted intense interest in the scientific community. In this review, we first present a discussion of the fundamental electronic nature of organic semiconductors, processing techniques, and their application to two main classes of optoelectronic devices, light emitting diodes, and photovoltaics. The second part of the review introduces organic photovoltaics in depth, including their operation principles, development history, current state of the art, and routes for further improvement. [ABSTRACT FROM PUBLISHER]

Three coumarin derivatives, 7-hydroxy-3-(2-pyridyl)coumarin ( HPC), 7-(4-(5-(4- tert-butylphenyl)-1,3,4-oxadiazol-2-yl)benzyloxy)-3-(2-pyridyl)coumarin ( Ox-PC), and 7-(4-(9H-carbazol-9-yl)butoxy)-3-(2-pyridyl)coumarin ( Cz-PC), were synthesized and characterized by elemental analysis, 1H NMR, FT-IR, and UV–vis absorption spectra. The fluorescence behaviors of the compounds in methanol solutions and solid states were investigated. HPC exhibits weak green emission, whereas Cz-PC and Ox-PC show strong blue emissions in dilute solutions. [ABSTRACT FROM AUTHOR]

An author index for the 2011 issue of "Vox Sanguinis" is presented.

Photoluminescent semiconductor nanocrystals or quantum dots (QDs) are usually produced using expensive ligands and solvents at high temperature above 280°C to ensure high-quality optical properties, particularly the photoluminescence of QDs. The reproducibility of highly stable photoluminescence in QD preparation, in most cases, varies depending on many effects, such as the ligand used and temperature. Here a facile preparation of photoluminescent semiconductor CdTe nanocrystals or quantum dots (QDs) is conducted in the presence of caprylic acid at moderate temperatures between 80-140°C, which are much lower than the high temperatures used in conventional organic-phase preparation of CdTe QDs. The results show that the optical properties of CdTe QDs depend considerably on the reaction time, temperature and ligand used. [ABSTRACT FROM AUTHOR]

A review of sensors for artificial hands is presented in terms of their range, specifications and characteristics. There is a growing need for sensors due to the development of prosthetic hands that have multiple degrees of freedom requiring finger coordination into different postures. The sensing of force, position (angle), object-slip and temperature allows for the control of these hands automatically and frees the user from cognitive burden. To make the best possible use of individual sensing elements, future controllers will need to combine data from different types of sensor. They may also have an integral power supply using a small battery or harvest energy from their environment and transmit data wirelessly. [ABSTRACT FROM AUTHOR]

This paper introduces the fundamental physical characteristics of organic photovoltaic (OPV) devices. Photoelectric conversion efficiency is crucial to the evaluation of quality in OPV devices, and enhancing efficiency has been spurring on researchers to seek alternatives to this problem. In this paper, we focus on organic photovoltaic (OPV) devices and review several approaches to enhance the energy conversion efficiency of small molecular heterojunction OPV devices based on an optimal metal-phthalocyanine/fullerene (C60) planar heterojunction thin film structure. For the sake of discussion, these mechanisms have been divided into electrical and optical sections: (1) Electrical: Modification on electrodes or active regions to benefit carrier injection, charge transport and exciton dissociation; (2) Optical: Optional architectures or infilling to promote photon confinement and enhance absorption. [ABSTRACT FROM AUTHOR]

Intrinsically super- (H ∼ 40-70 GPa) and ultrahard (H ≥ 70 GPa) materials attain high hardness through their large intrinsic strength, whereas extrinsically super- and ultrahard materials reach such hardness through their nanostructure. The recent search for intrinsically super- and ultrahard materials has concentrated on those with high elastic moduli. Several examples are presented of materials with high zero-pressure elastic moduli but relatively low hardness, because, upon imposing a large lattice distortion or substantial plastic shear strain, they undergo an instability of their electronic structure. Recent progress is then elucidated in the understanding of the origin of ultrahardness of nc-TmN/a-Si3N4 nanocomposites (Tm = transition metal that forms hard and stable nitrides), in which 3-4 nm size TmN nanocrystals are joined together by about a monolayer thick SiNx interface material layer. A combined ab initio DFT calculation of the ideal shear strength of the interfaces between the plastically non-deformable randomly oriented TmN grains, followed by Sachs-type averaging of these shear resistances in space to obtain a uniaxial yield strength, Y, employing a proper pressure enhancement of Y and considering the Tabor relation between the hardness H and yield strength Y, shows that these materials can reach hardness significantly larger than diamond, when correctly prepared and essentially free of defects. Such superhard nanocomposites are already available on an industrial scale as protective coatings on tools for machining, such as for drilling, milling, turning, forming, stamping and the like. [ABSTRACT FROM AUTHOR]

Mesoporous molecular sieve Ti-HMS, which possesses uniform wormlike structure and high specific surface area, was used as the support of anti-inflammatory drug ibuprofen. The samples before and after charging with ibuprofen were characterized using X-ray diffraction, UV–visible and thermal gravimetry. The loading amount and release rates on Ti-HMS with different titanium content and pore size were investigated systematically. It has been shown that Ti-HMS can adsorb ibuprofen and be used in drug delivery system. With the increase of framework titanium content, the loading amount of ibuprofen increases. The larger pore size also facilitates the loading and release of ibuprofen. [ABSTRACT FROM AUTHOR]

The magnetic properties of transition-metal (TM)-doped n-type ZnTmO are theoretically analyzed and compared to the published experimental results. For the two most studied cases of TM = Mn, Co, we demonstrate the interest of magnetic resonance experiments for the investigation of the origin of sometimes observed ferromagnetism and paramagnetic properties in single-phase material. The conclusion is that ferromagnetism in ZnTMO is extrinsic and related to the second phase formation during the growth or after annealing. Substitutional TM (Mn, Co) in ZnO gives rise to antiferromagnetic nearest-neighbor interactions similar to the case of the other TM-doped II-VI compounds. [ABSTRACT FROM AUTHOR]

Carbon-iron oxide microspheres' black pigments (CIOMBs) had been prepared via ultrasonic spray pyrolysis of aqueous solutions containing ferrous chloride and glucose. Due to the presence of carbon, CIOMBs not only exhibited remarkably acid resistance, but also could be well dispersed in both polar solvents and nonpolar solvent. Finally, dispersions of hollow CIOMBs in tetrachloroethylene had successfully been applied in electrophoretic displays. [ABSTRACT FROM AUTHOR]

The increase in energy production costs for fossil fuels has led to a search for an economically viable alternative energy source. One alternative energy source of particular interest is solar energy. A promising alternative to inorganic materials is organic semiconductor polymer solar cells due to their advantages of being cheaper, light weight, flexible and made into large areas by roll-to-roll processing. However, the conventional architecture that is typically used for fabricating solar cells requires high vacuum to deposit the top metal electrode which is not suitable for roll-to-roll processing. Recently an inverted device architecture has been investigated as a suitable architecture for developing the ideal roll-to-roll type processing of polymer-based solar cells. This review will go over the recent advances and approaches in the development of this type of inverted device architecture. We will highlight some of the work that we have done to integrate materials, device, interface, and processing of the inverted device architecture platform to produce more idealized polymer-based solar cells. [ABSTRACT FROM AUTHOR]

We report an experimental and modeling study of ZnS ySe1− y/GaAs (001) structures, all of which comprised a uniform top layer of ZnS0.014Se0.986 grown on a compositionally graded buffer layer or directly on the GaAs substrate. High-resolution x-ray diffraction was used to estimate dislocation densities on type A slip systems, with misfit dislocation (MD) line segments oriented along the $$ [1\bar{1}0] $$ direction, and type B slip systems, with MD line segments oriented along a [110] direction. A control sample having no graded buffer exhibits equal dislocation densities on the two types of slip systems ( DA ≈ DB ≈ 1.5 × 108 cm−2), but a forward-graded (FG) structure (grading coefficient of 27 cm−1) exhibits 20% more dislocations on the type B slip systems ( DA ≈ 1.6 × 108 cm−2 and DB ≈ 1.9 × 108 cm−2) and a steep forward-graded structure (grading coefficient of 54 cm−1) exhibits 50% more type B dislocations ( DA ≈ 2 × 108 cm−2 and DB ≈ 3 × 108 cm−2). The insertion of an overshoot interface reduced the dislocation densities in the uniform top layer by promoting annihilation and coalescence reactions, but type B dislocations were removed more effectively. Based on equilibrium calculations the overshoot graded layer in the steep graded overshoot structure is expected to exhibit large compressive and tensile strains, with a reversal in the sign of the strain near its middle, which may promote annihilation and coalescence reactions between threading dislocations. [ABSTRACT FROM AUTHOR]

Organic food is the development trend of food in the world today. China's green food is a kind of food with pollution-free, safety, high-quality and nutritious properties, similar to organic food in the international market. The Chinese government has paid attention to the sustainable development of agro-ecosystems under the pressures of population growth and agricultural expansion since the 1980s and began to develop a green food industry in 1990. After the development of about two decades, now the Chinese green food industry has already entered a fast-growth stage. It has reached a considerable scale and is expanding rapidly. The share of green food in the global market is continuously increasing and a two-tier certification system has been established. However, green food's further development is still facing some difficulties and problems. This paper mainly analyzes those problems and discusses reasonable solutions. Specifically, this paper first gives a detailed introduction to green food and the green food industry in China, and then analyzes the major problems impeding the further development of green food industry, such as unreasonable product structure and enterprise structure, incomplete market system and backward certification system. Finally, suggestions on product structure, enterprise structure, publicity, market, certification system and governmental policies are put forward. [ABSTRACT FROM AUTHOR]

Adequacy of approximation of ellipsoidal particles composed of a set of sub-spheres for numerical Discrete Element Method (DEM) simulations is examined. The algorithm of adaptive hierarchical multi-sphere (MS) model is suggested for composing elliptical particles. Numerical simulation of the piling problem is used as a test problem for evaluating the adequacy of MS model approximation in comparison to the model of smooth ellipses for multiparticle system. The accuracy of MS approximation with the increasing number of sub-spheres is examined in detail by comparison of macroscopic and microscopic parameters of granular dynamics. It was determined that the data on macroscopic parameters yielded by the MS model tend to converge to those of the smooth ellipsoid with the increasing number of the constituent sub-spheres, and the MS model approximates the smooth perfect ellipsoid with a reasonable number of sub-spheres within the limits of the appropriate tolerance. It can be concluded that a multi-sphere model remains a realistic and relatively simple particle model applicable to DEM simulations of the behaviour of the real smooth and rough elliptically shaped particles. [ABSTRACT FROM AUTHOR]

A general approach has been designed to blue, green, and red pigments by metal ions doping hollow TiO2. The reaction involves initial formation of PS at TiO2 core–shell nanoparticles via a mixed-solvent method, and then mixing with metal ions solution containing PEG, followed calcining in the atmosphere. The as-prepared hollow pigments exhibit uniform size, bright color, and tunable density, which are fit for electronic paper display. [ABSTRACT FROM AUTHOR]

We have studied the structural, electrical, optical, and optoelectronic properties of N-doped and Al-N co-doped ZnO films grown by sol–gel technique. Both the undoped and doped films have a hexagonal wurtzite-type structure. The undoped film shows a very low electron concentration. The N-doped film exhibits an anomalous conduction type, while the Al-N co-doped film shows relatively stable p-type conduction. Though the transparency in the visible region is retained in the doped films, its optical qualities are degraded as indicated by photoluminescence results. The N-doped film has better response to ultraviolet light compared with the undoped and co-doped films. These results are important for the growth and development of p-type ZnO films using the very low-cost sol–gel method. [ABSTRACT FROM AUTHOR]

The evolution and emergence of organic solar cells and hybrid organic-silicon heterojunction solar cells have been deemed as promising sustainable future technologies, owing to the use of π-conjugated polymers. In this regard, the scope of this review article presents a comprehensive summary of the applications of π-conjugated polymers as hole transporting layers (HTLs) or emitters in both organic solar cells and organic-silicon hybrid heterojunction solar cells. The different techniques used to synthesize these polymers are discussed in detail, including their electronic band structure and doping mechanisms. The general architecture and principle of operating heterojunction solar cells is addressed. In both discussed solar cell types, incorporation of π-conjugated polymers as HTLs have seen a dramatic increase in efficiencies attained by these devices, owing to the high transmittance in the visible to near-infrared region, reduced carrier recombination, high conductivity, and high hole mobilities possessed by the p-type polymeric materials. However, these cells suffer from long-term stability due to photo-oxidation and parasitic absorptions at the anode interface that results in total degradation of the polymeric p-type materials. Although great progress has been seen in the incorporation of conjugated polymers in the various solar cell types, there is still a long way to go for cells incorporating polymeric materials to realize commercialization and large-scale industrial production due to the shortcomings in the stability of the polymers. This review therefore discusses the progress in using polymeric materials as HTLs in organic solar cells and hybrid organic-silicon heterojunction solar cells with the intention to provide insight on the quest of producing highly efficient but less expensive solar cells. [ABSTRACT FROM AUTHOR]

The sustainability of live commerce is closely dependent on the impulse buying behavior of consumers because of its live characters compared to the traditional e-commerce mode. Hunger marketing is a widely adopted mode in live commerce, however, the influencing factors on impulse buying behavior of consumers under the mode of hunger marketing in live commerce is currently lacking. Here, based on SOR theory, we carefully studied how external stimulus variables (anchor characteristics, online comments, logistics service quality, promotion incentive information, and promotional time limit) affected consumers' impulse buying behavior under the inner mechanism reaction factors (perceived trust and perceived value). By collecting questionnaires from 533 Chinese online consumers, we processed these data using SPSS23.0 and analyzed them using the structural equation model (SEM) generated by AMOS 25.0. The results showed that extrinsic stimulus variables (except for the promotional time limit variable) have significant positive effects on impulse buying behavior through partial or total positive effects on intrinsic mechanisms. We analyzed the reasons for all these results in detail, and thought the reason that the promotional time limit did not have a significant impact on the perceived value might be due to the rapid increase in the frequency of live commerce. Moreover, we also put forward the suggestions on the basis of these influencing factors to improve the sustainable development of live commerce. [ABSTRACT FROM AUTHOR]

Humans are exposed to a complex mix of man-made electric and magnetic fields (MFs) at many different frequencies, at home and at work. Epidemiological studies indicate that there is a positive relationship between residential/domestic and occupational exposure to extremely low frequency electromagnetic fields and some types of cancer, although some other studies indicate no relationship. In this review, after an introduction on the MF definition and a description of natural/anthropogenic sources, the epidemiology of residential/domestic and occupational exposure to MFs and cancer is reviewed, with reference to leukemia, brain, and breast cancer. The in vivo and in vitro effects of MFs on cancer are reviewed considering both human and animal cells, with particular reference to the involvement of reactive oxygen species (ROS). MF application on cancer diagnostic and therapy (theranostic) are also reviewed by describing the use of different magnetic resonance imaging (MRI) applications for the detection of several cancers. Finally, the use of magnetic nanoparticles is described in terms of treatment of cancer by nanomedical applications for the precise delivery of anticancer drugs, nanosurgery by magnetomechanic methods, and selective killing of cancer cells by magnetic hyperthermia. The supplementary tables provide quantitative data and methodologies in epidemiological and cell biology studies. Although scientists do not generally agree that there is a cause-effect relationship between exposure to MF and cancer, MFs might not be the direct cause of cancer but may contribute to produce ROS and generate oxidative stress, which could trigger or enhance the expression of oncogenes. [ABSTRACT FROM AUTHOR]

Global energy demand is increasing; thus, emerging renewable energy sources, such as organic solar cells (OSCs), are fundamental to mitigate the negative effects of fuel consumption. Within OSC's advancements, the development of efficient and stable interface materials is essential to achieve high performance, long-term stability, low costs, and broader applicability. Inorganic and nanocarbon-based materials show a suitable work function, tunable optical/electronic properties, stability to the presence of moisture, and facile solution processing, while organic conducting polymers and small molecules have some advantages such as fast and low-cost production, solution process, low energy payback time, light weight, and less adverse environmental impact, making them attractive as hole transporting layers (HTLs) for OSCs. This review looked at the recent progress in metal oxides, metal sulfides, nanocarbon materials, conducting polymers, and small organic molecules as HTLs in OSCs over the past five years. The endeavors in research and technology have optimized the preparation and deposition methods of HTLs. Strategies of doping, composite/hybrid formation, and modifications have also tuned the optical/electrical properties of these materials as HTLs to obtain efficient and stable OSCs. We highlighted the impact of structure, composition, and processing conditions of inorganic and organic materials as HTLs in conventional and inverted OSCs. [ABSTRACT FROM AUTHOR]

A series of mathematical models were proposed to calculate the roll force, torque and power for cold strip asymmetrical rolling by means of the slab method, taking the percentages of the forward-slip, backward-slip and cross-shear zones into account. The friction power, plastic work and total energy consumption can be obtained by the models. The effects of variable rolling parameters—such as the speed ratio, entry thickness, friction coefficient and front and back tension—on the process of asymmetrical rolling are analyzed. In all cases, an increase in speed ratio leads to an increase in friction work and its proportions. The increase in entry thickness and deformation resistance causes both friction work and plastic deformation work to increase. The proportion of friction work decreases with increasing deformation resistance, entry thickness, front tension and back tension. In the circumstances of a thin strip being rolled with a large speed ratio, the proportion of friction work could exceed that of plastic deformation work. The concept of a threshold point of friction work was proposed to explain this phenomenon. As an example, threshold points T1, T2, T3 with the effect of the entry thickness and S1, S2, S3 with the effect of the friction coefficient have been obtained by computation. Finally, the experiment of the strip asymmetrical rolling was conducted, and a maximum error of 9.7% and an RMS error of 5.9% were found in the comparison of roll forces between experimental measurement values and calculated ones. [ABSTRACT FROM AUTHOR]

We report on a green, dual emissive quantum-dot light-emitting diode (QLED) using alumina (Al)-doped ZnO (AZO) to adjust the band offset between the cathode and QD-emitting layers. The dual emissive QLED structure was designed by enhancing the efficient hole injection/transfer and slowing down the electron injection/transfer from AZO to the QD. The QLEDs presented a maximum luminance of 9450 cd/m2, corresponding to a power efficiency of 15.7 lm/W, a current efficiency of 25.5 cd/A, as well as a turn-on voltage of 2.3 V. It is worth noting that the performance of the dual emissive QLED is comparable to that of a single emissive QLED. Therefore, there is a 1.3-fold enhancement in the performance of the QLED based on the AZO cathode due to the balanced charge injection/transfer. [ABSTRACT FROM AUTHOR]

Osteonecrosis of the jaws (ONJ) usually has a clear etiology. Local infection or trauma, radiotherapy and drugs that disrupt the vascular supply or bone turnover in the jaws are its major contributors. The thrombotic occlusion of the bone's venous outflow that occurs in individuals with hereditary thrombophilia and/or hypofibrinolysis has a less known impact on jaw health and healing capability. Our research provides the most comprehensive, up-to-date and systematized information on the prevalence and significance of hereditary thrombophilia and/or hypofibrinolysis states in ONJ. We found that hereditary prothrombotic abnormalities are common in patients with ONJ refractory to conventional medical and dental treatments. Thrombophilia traits usually coexist with hypofibrinolysis traits. We also found that frequently acquired prothrombotic abnormalities coexist with hereditary ones and enhance their negative effect on the bone. Therefore, we recommend a personalized therapeutic approach that addresses, in particular, the modifiable risk factors of ONJ. Patients will have clear benefits, as they will be relieved of persistent pain and repeated dental procedures. [ABSTRACT FROM AUTHOR]

Surface plasmon resonance-based biosensor has been fabricated using self-assembled monolayer (SAM) of β-merceptoethanol (MCE) deposited on gold (Au) substrate. The double stranded calf thymus deoxyribonucleic acid (dsCT-DNA) has been immobilised onto MCE/Au electrode using N-ethyl-N'-(3-dimethylaminopropyl) carbodiimide and N-hydroxysuccinimide (EDC/NHS) chemistry. This dsCT-DNA/MCE/Au bioelectrode has been characterised using cyclic voltammetry, scanning electron microscopy (SEM) and X-ray photoelectron spectrometry (XPS), respectively. The detection limit of arsenic trioxide has been estimated as 0.01 × 10-6 g mL-1. [ABSTRACT FROM AUTHOR]

The effect of multi-step austempering treatments on the microstructure and mechanical properties of a novel medium carbon high silicon carbide-free bainitic steel was studied. Five different isothermal treatment processes were selected, including single-step isothermal treatments above martensite start temperature (at 350 °C and 370 °C, respectively), and three kinds of two-step routes (370 °C + 300 °C, 370 °C + 250 °C, and 350 °C + 250 °C). In comparison with single-step austempering treatment adopting a two-step process, a microstructure with a bimodal-size distribution of bainitic ferrite and without martensite was obtained. Bainitic transformation was studied using dilatometry both for single-step and two-step routes and the specimens were completely characterised by electron microscopy (SEM and TEM), X-ray diffraction (XRD) and standard tensile tests. The mechanical response of the samples subjected to two-step routes was superior to those treated at a single temperature. [ABSTRACT FROM AUTHOR]