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The control of phase ratio and residual stress is a crucial subject for the structural integrity of duplex stainless steel welded components. Therefore, this paper aims to clarify the evolution of phase ratio and its effect on residual stress for duplex stainless steel multipass welded joints by a thermo-metallurgical-mechanical coupled welding model, alongside the crucial experiments which contribute to the development and validation of the coupled model. The developed model takes both the precipitation and dissolution behavior of austenite under repeated thermal cycles into consideration, thereby demonstrating a remarkable ability to predict the distribution of phase ratio and residual stress. The influencing mechanism of solid-state phase transformation on residual stress is discussed extensively. The results reveal that, for the duplex stainless steel welded joints by gas tungsten arc welding, excessive austenite is often formed within the welding zone particularly for the middle passes, while it is the occurrence of ferritization at the heat affected zone. The effect of phase transformation on residual stress is mainly presented by the change of mechanical properties and phase volume. The overtransformation from ferrite to austenite tends to induce a higher tensile residual stress, vice versa, compressive stress. In addition, it is challenging to achieve phase balance through heat input alone. However, a smaller heat input is recommended to minimize residual stress while ensuring welding penetration. This paper serves as a theoretical foundation for controlling the phase ratio and mitigating residual stress during the welding of duplex stainless steel, thereby contributing to the enhancement of weld quality and structural reliability. • A thermo-metallurgical-mechanical coupled welding model was proposed to predict the phrase ratio and residual stress of DSS. • The mechanism of solid-state phase transformation on residual stress was clarified. • The role of heat input on residual stress and phase ratio was discussed. [ABSTRACT FROM AUTHOR]

• The correlation among heterogeneous microstructure, cyclic hardening/softening and fatigue failure behavior was analyzed extensively. • The fracture location was changed with the fatigue amplitude due to the amplitude-dependent and heterogeneous cyclic hardening/softening of BM and WM. • A modified cyclic constitutive model was proposed to precisely predict the heterogeneous cyclic mechanical response and failure location for both stress-controlled and strain-controlled conditions. This work performed experimental and modeling investigations on the fatigue failure mechanism of duplex stainless steel welded joints, and the correlation among heterogeneous microstructure, cyclic hardening/softening and fatigue failure behavior was analyzed extensively. A series of experiments including the characterization of microstructure by the electron back-scattered diffraction observation and fatigue mechanical tests assisted by digital image correlation technique were performed. The results show that at the lower stress amplitudes (approximately 520 MPa), the fatigue failure occurred in the weld metal, while it shifted to the base metal at higher amplitudes. Due to the grain refinement, the strain amplitude of weld metal was lower than that of base metal, particularly at the higher amplitudes, leading to the final failure at the base metal. However, at the lower amplitudes, due to the effect of Kurdjumov-Sachs orientation relationship at the weld metal, its cyclic softening behavior was much drastic than that of base metal, resulting in the overshoot of strain amplitude during fatigue process and finial rupture at the weld metal. A cyclic constitutive model was developed by considering the amplitude-dependent and heterogeneous cyclic hardening/softening, to accurately predict the cyclic mechanical response and fatigue failure location for both stress-controlled and strain-controlled conditions. This work can be used as guidance of structure integrity assessment and life prediction for the engineering components of duplex stainless steel. [ABSTRACT FROM AUTHOR]

In this paper, finite-time stabilization is investigated in depth for stochastic nonlinear systems with stochastic inverse dynamics. The contributions of this work are characterized by the following novel features: (i) Motivated by the concept of stochastic integral input-to-state stability (SiISS) and the existing stochastic finite-time stability theorem, a new concept of finite-time stochastic integral input-to-state stability (FT-SiISS) using Lyapunov function is first introduced, and an inclusion relationship among three types of stochastic stability, i.e., FT-SiISS, FT-SISS and SISS, is rigorously established. On the basis of FT-SiISS, we develop two new FT-SiISS small-gain conditions and discuss their relationship. Then, to analyze finite-time stability of stochastic nonlinear systems with FT-SiISS inverse dynamics, a stochastic finite-time stability theorem is improved. (ii) As the application of (i), we propose a unified finite-time control method, which can simultaneously handle stochastic nonlinear systems with FT-SiISS or FT-SISS inverse dynamics, and guarantee that the closed-loop system has an almost surely continuous solution, all the closed-loop signals are bounded almost surely, and its trivial solution is stochastically finite-time stable. [ABSTRACT FROM AUTHOR]

Abstract In this study, the cyclic mechanical characters of 316L stainless steel at elevated temperature are extensively investigated by the experimental and cyclic constitutive models. The experiments include the monotonic tensile tests with different loading rates and the low cycle fatigue tests considering the effect of strain amplitudes, strain rates and loading sequences. The evolution of cyclic stress amplitudes, hysteresis loops and elastic modulus under various loading conditions are comprehensively analyzed. The experimental results show that the 316L steel at elevated temperature performs a typical three-stage cyclic mechanical response, i.e., initial hardening, subsequent saturation and final accelerated softening. The cyclic softening in both stiffness and flow stress is mainly caused by the nucleation of micro-voids or micro-cracks, and the subsequent coalesce and propagation. Furthermore, although the nearly rate-independent mechanical behavior is observed at monotonic tensile and first several fatigue cycles due to the DSA effect, the cyclic hardening/softening behavior shows a significant strain-rate and loading history dependence. Finally, inspired by the experimental observations and analyses, a damage-coupled cyclic elastic-viscoplastic constitutive model involving strain-range, strain-rate and loading history dependence is proposed to predict the complex cyclic behaviors of the material at elevated temperature. A hardening factor is incorporated into the Chaboche kinematic hardening equations to model the kinematic-induced hardening behavior. And the plastic strain memory surface and the maximum plastic strain rate are introduced to model the strain-range, strain-rate and loading history dependence of cyclic behavior. The proposed model is proved to effectively describe the complex evolution of not only cyclic stress amplitude but also hysteresis loops for the 316L steel at elevated temperature. Highlights • The cyclic response and fatigue mechanism for the 316L steel at room and elevated temperature were compared. • The various tensile and LCF tests considering the effect of strain range, strain rate and loading sequence were carried out. • The fatigue damage was determined experimentally, and incorporated into the cyclic elastic-viscoplastic constitutive model. • The relationship between strain rate, DSA effect and cyclic behavior were investigated and realized by the proposed model. • The proposed model can predict the evolution of not only cyclic stress amplitude but also hysteresis loops accurately. [ABSTRACT FROM AUTHOR]

For effectively treating tumor related-bone defects, design and fabrication of multifunctional biomaterials still remain a great challenge. Herein, we firstly fabricated magnetic SrFe 12 O 19 nanoparticles modified-mesoporous bioglass (BG)/chitosan (CS) porous scaffold (MBCS) with excellent bone regeneration and antitumor function. The as-produced magnetic field from MBCS promoted the expression levels of osteogenic-related genes (OCN, COL1, Runx2 and ALP) and the new bone regeneration by activated BMP-2/Smad/Runx2 pathway. Moreover, the SrFe 12 O 19 nanoparticles in MBCS improved the photothermal conversion property. Under the irradiation of near-infrared (NIR) laser, the elevated temperatures of tumors co-cultured with MBCS triggered tumor apoptosis and ablation. As compared with the pure scaffold group, MBCS/NIR group possessed the excellent antitumor efficacy against osteosarcoma via the hyperthermia ablation. Therefore, the multifunctional MBCS with excellent bone regeneration and photothermal therapy functions has a great application for treating the tumor-related bone defects. [ABSTRACT FROM AUTHOR]

In this paper, the relaxation of weld residual stress in a 316L stainless steel weld joint under cyclic loading was researched by experimental and finite element method (FEM). Initially, the as-weld residual stresses were calculated by a sequential coupling thermo-mechanical FEM. Subsequently, a cyclic plasticity constitutive model was proposed to study the redistribution of the residual stress by the cyclic load. Significant residual stresses are released during the first few cycles. Especially, about 45–60% of the maximum residual stresses are released during the first cycle because of the plastic deformation caused by the superposition between the as-weld residual stress and the applied load. More residual stresses are released with the increase of the stress amplitude and cyclic number. An analytical model, which considers the effects of the initial residual stress, yield stress, stress amplitude, and number of cycles, was proposed to predict the relaxation of the weld residual stress by the cyclic load. In addition, experimental measurements were also performed to validate this model. Experimental results prove that the proposed model can be used as a valid tool to predict the relaxation of residual stress by the fatigue load. [ABSTRACT FROM AUTHOR]

• >Synthetical effect of material inhomogeneity and welding defect on fatigue behavior. • >New structure strain method including heterogeneous plasticity and stress singularity. • >Evolution of fatigue mode with geometric configurations and cyclic amplitudes. • >A damage tolerance-based fatigue design concept to guide manufacture of welded joints. This paper performed experimental and analytical investigations on the synthetical effect of material inhomogeneity and welding defects on the fatigue behavior of 2205 duplex stainless steel cruciform welded joints. A series of experiments were performed, including microstructure characterization by the electron back-scattered diffraction, fatigue mechanical tests assisted by digital image correlation technique and fracture morphology observations by scanning electron microscope. Results show that fatigue life and failure location of cruciform welded joints depended heavily on their geometric configurations for lower cyclic amplitudes. However, with the elevation of loading, material inhomogeneity played a greater roles, leading to the change of fatigue failure mode with both geometric configuration and cyclic stress amplitude. To quantize the effects of welding defects and material inhomogeneity, a modified structure strain method was proposed by considering the heterogeneous plastic properties, to accurately predict both fatigue lifetime and failure location of cruciform welded joints at both low and high cycles fatigue. Lastly, a damage tolerance-based fatigue design method was discussed to guide the highly-reliable manufacture and damage detection of duplex stainless steel cruciform welded joints in the engineering. [ABSTRACT FROM AUTHOR]

• A multiscale model was proposed to accurately predict the heterogeneous and multiscale elasto-plastic properties of 2205 DSS welded joints. • The contribution of Peierls–Nabarro stress, solid solution strengthening, grain/phase boundary, and dislocations density on the macro-mechanical properties (YS and UTS) was quantified. • The evolution of heterogeneous micro-mechanical responses with two constitutive phases with the elevation of loads was predicted accurately. • The banded GBAs and its adjacent ferrite were more prone to plastic-deformed. This work aims to reveal the inherent dependency between the heterogeneous microstructure induced by the metallurgical transformation during welding of 2205 duplex stainless steel (DSS) and its macroscopic and microscopic elasto-plastic properties by experiments and models. A multiscale model was developed by combining a macro-constitutive model incorporating the physically-based yield strength and a crystal plasticity model considering both the micro-mechanical properties of two phases and their realistic morphology. The results show that the heterogeneous macro-mechanical properties of base metal (BM), heat affected zone (HAZ), and weld material (WM), as well as their micro-mechanical responses related to phase morphology, ratio, and grain size, can be accurately predicted. The contribution of Peierls–Nabarro stress, solid solution strengthening, grain/phase boundary, and dislocations density on macro-yield and tensile strengths was quantified, and WM was proven to have greater yield and tensile strengths due to the greater contribution of grain refinement and solid solution strengthening. In addition, a transition mechanism of the deformation-bearing phase from austenite to ferrite with the increase of load was proved, and the banded grain boundary austenite (GBA) and its adjacent ferritic grains were prone to plastic-deformation. This work can be used as guidance of structure integrity assessment and welding process optimization for the engineering components of DSS. [ABSTRACT FROM AUTHOR]

Objective The objective was to observe damage of hippocampus in rats after exposure to infrasound, and to assess HSP70 expression in hippocampus. Methods SD rats in the experimental group were exposed to 140 dB (8 Hz) infrasound for 2 h per day for 3 days. The morphology of the hippocampus was examined by transmission electronic microscopic (TEM). Cell apoptosis was observed by TUNEL staining at 0 h, 24 h, 48 h, and 2 w after exposure. HSP70 expression was detected by immunohistochemistry (IHC) and Western blotting (WB). Results TEM showed that hippocampus was significantly damaged by exposure, and exhibited recovery 1 week after exposure. The TUNEL data showed that neuronal apoptosis after exposure was significantly higher than in the control rats at 24 h and 48 h, and the apoptotic cells decreased one week after exposure. IHC and WB showed HSP70 expression was significantly higher in the exposed rats, peaked at 24 h. Conclusion Exposure to 140 dB (8 Hz) infrasound for 2 h per day for 3 days appeared to induce damage to the hippocampus of rats, based on changes in ultrastructure and increased cell apoptosis. However, recovery from the damage occurred overtime. HSP70 expression also increased after the exposure and decreased by 48 h. [ABSTRACT FROM AUTHOR]

This paper is concerned with the problem of output feedback stabilization of stochastic planar nonlinear systems with output constraint. By introducing some new nonlinear mappings, adding a power integrator and homogeneous domination techniques, according to different value ranges of the homogeneous degree in the same form of assumptions, we establish two new design and analysis frames of output feedback stabilization to achieve respectively stochastic asymptotic stability (or asymptotical stability in probability) and stochastic finite-time stability of the trivial solution of the closed-loop system while guaranteeing the requirements of almost sure boundedness of the closed-loop signals and the symmetric output constraint. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, by introducing a combined method of sign function, homogeneous domination and adding a power integrator, and overcoming several troublesome obstacles in the design and analysis, the problem of state feedback control for a class of nonlinear high-order feedforward systems with the nonlinearity's order being relaxed to an interval rather than a fixed point is solved. [Copyright &y& Elsevier]

Abstract: In this paper, we consider the problem of global stabilization for a class of stochastic high-order feedforward nonlinear systems with time-varying delay. By introducing the homogeneous domination design method and constructing the appropriate Lyapunov–Krasovskii functional, a state feedback controller is constructed to drive the closed-loop system to be globally asymptotically stable in probability. [Copyright &y& Elsevier]

This paper investigates finite-time stabilization of output-constrained stochastic high-order nonlinear systems with stochastic inverse dynamics and high-order and low-order nonlinearities. By characterizing the unmeasured stochastic inverse dynamics with finite-time stochastic input-to-state stability and introducing nonlinear transformations, a new design and analysis method is constructed. It is rigorously proved that all the closed-loop signals are bounded almost surely, the asymmetric output constraint isn't violated almost surely, and the trivial solution of the closed-loop system is finite-time stable in probability. [ABSTRACT FROM AUTHOR]

Abstract: The truffle species Tuber anniae was originally described from the U.S. Pacific Northwest and is purported to be uncommon. Here, we report for the first time on the fruiting of closely related taxa in Baltic Rim countries. These truffles were found in a forest dominated by Scots pine in eastern Finland. Mycorrhizal analyses confirmed its symbiosis with Pinus sylvestris. Morphological observations of ascomata and mycorrhizae, and phylogenetic analyses confirmed that these white truffles belong within the group of Tuber puberulum (i.e., Puberulum clade). Further, they group in Clades II and III of the T. anniae species-complex. With the inclusion of sequences from GenBank we are able to demonstrate that the previously unnamed environmental clade (Clade II) has been found as ectomycorrhiza in symbiosis with pine, birch, oak, aspen and even orchids in Europe. Thus, the T. anniae species-complex as a whole (and two of the three clades within) exhibit considerable geographic disjuncts: Northwestern North America and the Baltic Rim of Europe. Clade II, which was collected in agricultural soils in Finland and along roadsides in Alaska, may also be adapted for colonization into new habitats. This may help to explain its presence in New Zealand (where Tuber is not native), which most likely resulted from human-mediated dispersal of these fungi through forestry or the nursery trade. Based on our results, we hypothesize that management practices such as organic and lime amendments, along with aeration, are beneficial to the fruiting of T. anniae. Further research is needed to determine the edibility of these species and whether commercial markets can be developed. [Copyright &y& Elsevier]

Abstract: This paper investigates a class of stochastic feedforward nonlinear systems with time-varying delay. By introducing the homogeneous domination approach to stochastic systems, a state feedback controller is constructed to render the closed-loop system globally asymptotically stable in probability. [Copyright &y& Elsevier]

Abstract: An ultrasonic treatment technique was applied to a continuous photobioreactor with Rhodopseudomonas palustris CQK 01 suspension to enhance photo-hydrogen production performance. After the start-up period, R. palustris CQK 01 suspension in the photobioreactor was intermittently agitated by ultrasonic wave with a frequency of 20 kHz and then the hydrogen production performance was evaluated. The ultrasonic agitation significantly dropped the hydrogen concentration in the suspension from 300 μmol/L to 50 μmol/L and thus increased the hydrogen production rate and hydrogen yield by nearly 2 times as compared with conventional photobioreactor. Furthermore, the effects of the ultrasonic power and time, influent substrate flow rate and concentration were investigated and discussed, respectively. The maximum hydrogen production performance of the continuous photobioreactor with ultrasonic treatment was obtained under the conditions of ultrasonic power 40 W, agitation/interval time 3/7 s, substrate concentration 75 mmol/L and substrate flow rate 40 ml/h, leading to the hydrogen production rate of 1.12 mmol/L/h and hydrogen yield of 0.23 mol-H2/mol-glucose. [Copyright &y& Elsevier]

Abstract: This article further discusses the output feedback stabilization problem for stochastic high-order nonlinear systems with time-varying delay. Under the weaker conditions on nonlinearities in drift and diffusion vector fields, by using the idea of homogeneous domination approach, skillfully choosing an appropriate Lyapunov–Krasoviskii functional, and successfully solving several troublesome obstacles in the design and analysis procedure, an output feedback controller is constructed to render the closed-loop system globally asymptotically stable in probability. [Copyright &y& Elsevier]

Background: Titanium elastic nails (TENs) are commonly used to repair displaced midshaft clavicular fractures. Although several clinical studies have shown that the use of TENs is more effective and less invasive than traditional plate fixation, high rates of complications associated with TENs have been reported. This retrospective study compared the use of TENs with reconstruction plates in the treatment of displaced midshaft clavicular fractures. Materials and methods: From January 2005 to July 2007, 141 patients with displaced midshaft clavicular fractures were treated with TEN or plate fixation. At 6 and 24 months postoperatively, we evaluated the patients’ general health, operative complications, and functional recovery. Results: The mean bone union time of TEN patients was 12.4 ± 3.4 weeks, whereas that in the plate group was 14.4 ± 3.7 weeks. The time of union was significantly shorter in the TEN group than that in the plate group. There was no significant difference between these 2 groups’ rates of complications such as nonunion or malunion. Shoulder function scores were significantly better in the TEN group than in the plate group at 6 months postoperatively. There was no significant difference at 24 months postoperatively. Patients were more satisfied with the cosmetic appearance and overall outcome after TEN repair than after plate fixation. Conclusions: TEN fixation of displaced midshaft clavicular fractures allows for a faster functional recovery, higher patient satisfaction, and a more cosmetically satisfactory appearance than plate fixation. The complication rates of both TENs and reconstruction plates were similar. [ABSTRACT FROM AUTHOR]

Rationale and Objectives: The aim of this study was to validate the feasibility of assessing the efficacy of antiangiogenic therapy on VX2 tumors using three-dimensional computed tomographic (CT) angiography (CTA) combined with CT perfusion. Materials and Methods: Forty rabbits with VX2 tumors were randomly assigned to four groups according to different doses of antiangiogenic drug, which were administered intraperitoneally daily for 14 days. In each group, 10 animals were scanned using three-dimensional CTA and CT perfusion on days 1 and 2 after the latest administration of the drug. Tumor masses were sectioned, stained by immunohistochemistry, and processed for correlation between CT imaging and histology. Results: The numbers of new tumor vessels from CTA were significantly different among the four groups (P < .001). As the dose of the drug increased, blood flow and blood volume on CT perfusion increased linearly, but the mean transit time and permeability surface-area product decreased linearly (P < .001). Immunohistochemical analyses showed that microvascular density decreased, while both luminal vascular number and mature vessel number increased linearly as the drug dose increased (P < .001). CT manifestations were correlated well with histologic findings (P < .05). Conclusions: It is feasible to assess the efficacy of antiangiogenic therapy on VX2 tumors using three-dimensional CTA combined with CT perfusion. Three-dimensional CTA can display the morphologic changes of tumor vessels, while CT perfusion can predict the functional changes of tumor vessels after antiangiogenic therapy. [ABSTRACT FROM AUTHOR]

Abstract: This paper investigates output-feedback control for a class of stochastic high-order nonlinear systems with time-varying delay for the first time. By introducing the adding a power integrator technique in the stochastic systems and a rescaling transformation, and choosing an appropriate Lyapunov-Krasoviskii functional, an output-feedback controller is constructed to render the closed-loop system globally asymptotically stable in probability and the output can be regulated to the origin almost surely. A simulation example is provided to show the effectiveness of the designed controller. [Copyright &y& Elsevier]

Summary: Disabled-2 expression is reduced in many cancers, suggesting that it is a potential tumor suppressor protein. To elucidate the role of Disabled-2 in lung cancer, we examined the expression of Disabled-2, the Disabled-2–binding protein Axin, and DNA methyltransferase-1 in lung cancer tissues and corresponding normal lung tissues using immunohistochemistry and Western blots. We also determined the subcellular localization of Axin and Disabled-2 in A549 cells using confocal immunofluorescence. Disabled-2 expression was significantly reduced in lung cancers and was colocalized and coexpressed with Axin (correlation coefficient = 0.321, P < .001 for cytoplasmic expression; correlation coefficient = 0.393, P < .001 for nuclear expression). Reduced nuclear Disabled-2 expression was correlated with the differentiation (P = .048) and TNM stage (P = .048) of the tumor. The cytoplasmic expression of Axin was also correlated with differentiation (P = .042), whereas the nuclear expression of Axin was correlated with both histologic type (P = .001) and TNM stage (P < .001) of lung cancers. Expression of DNA methyltransferase-1 was negatively correlated with the cytoplasmic expression of Axin (correlation coefficient = −0.244, P = .012) but positively correlated with the histologic type (P = .004), differentiation (P = .036), TNM stage (P = .044), and lymphatic metastasis (P = .011). Expressions of Disabled-2 and Axin were concurrently reduced and correlated with the malignant phenotype of lung cancers. Enhanced expression of DNA methyltransferase-1 correlated with the reduced expression of Axin and could be a marker for lung cancer development and progression. [ABSTRACT FROM AUTHOR]

Abstract: This paper investigates the small-gain type conditions on stochastic iISS (SiISS) systems and makes full use of these conditions in the design and analysis of the controller. The contributions are as follows: (1) A new proof of the stochastic LaSalle theorem is provided; (2) The small-gain type conditions on SiISS are developed and their relationship is discussed; (3) Based on the stochastic LaSalle theorem and SiISS small-gain type conditions, the adaptive controllers are designed to guarantee that all of the closed-loop signals are bounded almost surely and the stochastic closed-loop systems are globally (asymptotically) stable in probability. [Copyright &y& Elsevier]

Abstract: This paper considers the problem of robust decentralized adaptive output feedback stabilization for a class of interconnected systems with dynamic input and output interactions and nonlinear interactions by using MT-filters and the backstepping design method. It is shown that the closed-loop decentralized system based on MT-filters is globally uniformly bounded, all the signals except for the parameter estimates can be regulated to zero asymptotically, and the and norms of the system outputs are also be bounded by functions of design parameters. The scheme is demonstrated by a simulation example. [Copyright &y& Elsevier]

Abstract: A Cu/Zn-superoxide dismutase (SOD) was characterized for the first time from Beauveria bassiana by gene cloning, heterogeneous expression and function analysis. This 154-aa SOD (BbSod1) was deduced from a 465-bp gene cloned, showing 49–96% sequence identity to Cu/Zn-SODs from other 57 fungi. BbSod1 and its form engineered with two site-directed mutations P143S and P145L (BbSod1-Mut) or a fused copper chaperon Lys7 (BbSod1-Lys7) were expressed well in Escherichia coli. Crude extracts and purified BbSod1-Mut from cell cultures exhibited much higher antioxidation activities than the counterparts of BbSod1-Lys7 whereas BbSod1 showed no substantial activity. The engineered enzymes were best induced by overnight incubation at 20°C in Luria-Bertani medium including 2.5mM Cu2+, 0.5mM Zn2+ and 0.5mM isopropyl-d-thiogalactopyranoside after 5-h growth to log-phase at 37°C. Our results highlight alternative means to producing highly active fungal Cu/Zn-SOD in E. coli by making use of the two site-directed mutations without chaperon. [Copyright &y& Elsevier]

Abstract: This paper describes the fabrication, characterization and application of a bismuth/poly (p-aminobenzene sulfonic acid) (Bi/poly(p-ABSA)) composite film-coated glassy carbon electrode for the electrochemical determination of azo compounds. This electrode was fabricated by depositing bismuth on the poly(p-ABSA) modified electrode at −0.9V. Azo compounds such as 1-(2-pyridylazo)-2-naphthol (PAN), 4-(2-pyridylazo)-resorcinol (PAR) and azobenzene were determined on this electrode by differential pulse voltammetry. Factors influencing the determination performance including the film preparation and solution pH have been optimized. This new electrode presented well-defined, reproducible and sharp determination signals. The results confirmed that the Bi/poly(p-ABSA) electrode offered high-quality stripping performance compared with the bismuth film electrode. Under the optimum conditions, the detection limits of PAN, PAR and azobenzene were 4.1×10−8, 3.3×10−8 and 3.8×10−8 molL–1, respectively. The influence of foreign substances on the signal was studied and the new electrode was successfully applicable to analysis of azo compounds in real beverage samples. [Copyright &y& Elsevier]

Objective: To investigate the effects of combined transplantation of neural stem cells (NSC) and olfactory ensheathing cells (OEC) on the motor function of rats with intracerebral hemorrhage. Methods: In three days after a rat model of caudate nucleus hemorrhage was established, NSCs and OEC, NSC, OEC (from embryos of Wistar rats) or normal saline were injected into hematomas of rats in combined transplantation group, NSC group, OEC group, and control group, respectively. Damage of neural function was scored before and in 3, 7, 14, 30 days after operation. Tissue after transplantation was observed by immunocytochemistry staining. Results: The scores for the NSC, OEC and co-transplantation groups were significantly lower in 14 and 30 days after operation than in 3 days after operation (P<0.05). The scores for the NSC and OEC groups were significantly lower than those for the control group only in 30 days after operation (P<0.05), while the difference for the NSC-OEC group was significant in 14 days after operation (P<0.05). Immunocytochemistry staining revealed that the transplanted OEC and NSC could survive, migrate and differentiate into neurons, astrocytes, and oligodendrocytes. The number of neural precursor cells was greater in the NSC and combined transplantation groups than in the control group. The number of neurons differentiated from NSC was significantly greater in the co-transplantation group than in the NSC group. Conclusion: Co-transplantation of NSC and OEC can promote the repair of injured tissue and improve the motor function of rats with intracerebral hemorrhage. [Copyright &y& Elsevier]