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Nerve injury can lead to defects in related motor functions. It is critical to achieve long‐term and convenient real‐time evaluation of motor function recovery status during nerve injury repair. In this study, an implantable PLLA/BTO piezoelectric sensor (PBPS) with good biodegradability and biocompatibility for real time evaluation of the motor function recovery after nerve injury is developed. PLLA fibers doped with BTO are employed as piezoelectric material in PBPS, which can convert the biomechanical signals generated by motion into electrical signals. PBPS can be implant simultaneously with commonly used tissue scaffolds for treatment in the rats with sciatic nerve injury. The linearity of the pressure and the output voltage of PBPS is ≈0.9445. For the evaluation effectiveness, as the treatment process progresses, the signals generated by PBPS exhibited good consistency with EMG signals, indicating effectively evaluation of the motor function. Moreover, the integration of PBPS and wireless module can break the limitations of time and space for sensing and realize wireless evaluation of motor function in rat. The implantable sensor based on PBPS may bring new ideas for the development of implantable bioelectronics. [ABSTRACT FROM AUTHOR]

Since the discovery of ion-exchange resins, they have been used in many fields, including pharmacy. Ion-exchange resin-mediated preparations can realize a series of functions, such as taste masking and regulating release. However, it is very difficult to extract the drug completely from the drug–resin complex because of the specific combination of the drug and resin. In this study, methylphenidate hydrochloride extended-release chewable tablets compounded by methylphenidate hydrochloride and ion-exchange resin were selected for a drug extraction study. The efficiency of drug extraction by dissociating with the addition of counterions was found to be higher than other physical extraction methods. Then, the factors affecting the dissociation process were studied to completely extract the drug from the methylphenidate hydrochloride extended-release chewable tablets. Furthermore, the thermodynamic and kinetic study of the dissociation process showed that the dissociation process obeys the second-order kinetic process, and it is nonspontaneous, entropy-decreasing, and endothermic. Meanwhile, the reaction rate was confirmed by the Boyd model, and the film diffusion and matrix diffusion were both shown to be rate-limiting steps. In conclusion, this study aims to provide technological and theoretical support for establishing a quality assessment and control system of ion-exchange resin-mediated preparations, promoting the applications of ion-exchange resins in the field of drug preparation. [ABSTRACT FROM AUTHOR]

Human physiological signals have an important role in the guidance of human health or exercise training and can usually be divided into physical signals (electrical signals, blood pressure, temperature, etc.) and chemical signals (saliva, blood, tears, sweat). With the development and upgrading of biosensors, many sensors for monitoring human signals have appeared. These sensors are characterized by softness and stretching and are self-powered. This article summarizes the progress in self-powered biosensors in the past five years. Most of these biosensors are used as nanogenerators and biofuel batteries to obtain energy. A nanogenerator is a kind of generator that collects energy at the nanoscale. Due to its characteristics, it is very suitable for bioenergy harvesting and sensing of the human body. With the development of biological sensing devices, the combination of nanogenerators and classical sensors so that they can more accurately monitor the physiological state of the human body and provide energy for biosensor devices has played a great role in long-range medical care and sports health. A biofuel cell has a small volume and good biocompatibility. It is a device in which electrochemical reactions convert chemical energy into electrical energy and is mostly used for monitoring chemical signals. This review analyzes different classifications of human signals and different forms of biosensors (implanted and wearable) and summarizes the sources of self-powered biosensor devices. Self-powered biosensor devices based on nanogenerators and biofuel cells are also summarized and presented. Finally, some representative applications of self-powered biosensors based on nanogenerators are introduced. [ABSTRACT FROM AUTHOR]

We report direct numerical simulation (DNS) results of hyporheic exchange for a flat river bed with two different particle roughness textures, at a surface flow friction Reynolds number of 395 and a bed permeability Reynolds number of 2.6. Transit time distributions (TTDs), subsurface flow patterns, and the interfacial volumetric fluxes are discussed. The transit time was quantified using a forward particle tracking method based on pure advection by three‐dimensional, pore‐resolved, time‐mean velocities. Results show that bed roughness induces deep subsurface flow paths that yield a TTD with a power‐law tail. Roughness obstructs the surface flow, creating interfacial pressure variations which induce subsurface flow. Next, the molecular diffusion is accounted for based on a random walk method and is shown to increase transit times regardless of roughness texture. This work demonstrates that particle roughness on a macroscopically flat sediment bed can induce significant hyporheic exchange that is fundamentally similar to that induced by bedforms. Plain Language Summary: Riverine flows are turbulent flows with wide range of scales of motion in both space and time. Driven and modified by natural and anthropogenic factors, channel flows interact with local features (e.g., bars, ripples, and dunes), and smaller features down to the scale of individual sediment grains. The magnitude of exchange of water with bed sediment (hyporheic exchange) and the time water molecules spend within the bed before reentering the channel are key details that control water quality in streams, as they determine the nature of biogeochemical processes. The role played by processes at the scale of individual grains and grain clusters (collectively referred to as bed roughness) have not been understood. We use direct simulation of turbulent flows and consider two "flat bed" scenarios with regular or random roughness at the sediment‐water interface. We show that bed roughness induces deep flow paths and long transit times similar to those produced by local features and that the roughness texture plays an important role. The results offer novel insights into small‐scale hyporheic flows and provide quantitative estimates of the inherent uncertainty that can be expected in estimates of hyporheic exchange due to changes at larger scales. Key Points: Transit times calculated with particle tracking using pore‐resolved velocities from direct numerical simulation (DNS) of turbulent surface‐subsurface flowsDNS enables direct evaluation and comparison of various mechanisms contributing to hyporheic exchangeRoughness texture modifies transit time values but not heavy‐tail slope of transit time distribution [ABSTRACT FROM AUTHOR]

Direct numerical simulations (DNSs) of an incompressible turbulent boundary layer on an airfoil (suction side) and that on a flat plate are compared to characterize the non-equilibrium turbulence and the effect of wall curvature on the flow. The two simulations effectively impose matching streamwise distributions of adverse pressure gradient (APG) quantified by the acceleration parameter (K). For the airfoil flow, an existing compressible DNS carried out by Wu et al. ["Effects of pressure gradient on the evolution of velocity-gradient tensor invariant dynamics on a controlled-diffusion aerofoil at Rec = 150,000," J. Fluid Mech. 868, 584–610 (2019)] of the flow around a controlled-diffusion airfoil is used. For the flat-plate flow, a separate simulation is carried out with the aim to reproduce the flow in the region of the airfoil boundary layer with zero to adverse pressure gradients. Comparison between the two cases extracts the effect of a mild convex wall curvature on velocity and wall-pressure statistics in the presence of APG. In the majority part of the boundary layer development, curvature effect on the flow is masked by that of the APG, except for the region with weak pressure gradients or a thick boundary layer where the effect of wall curvature appears to interact with that of APG. High-frequency wall-pressure fluctuations are also augmented by the wall curvature. Overall, the boundary layers are qualitatively similar with and without the wall curvature. This indicates that a flat-plate boundary layer DNS may serve as a low-cost surrogate of a boundary layer over the airfoil or other objects with mild curvatures to capture important flow features to aid modeling efforts. [ABSTRACT FROM AUTHOR]

The dynamical effects of roughness geometry on the response of a half-height turbulent channel flow to an impulse acceleration are investigated using direct numerical simulations. Two rough surfaces different in the surface height spectrum are compared between themselves and with a smooth-wall baseline case. Both rough cases develop from a transitionally rough state to a fully rough one. Results show that on rough walls the thickness of the roughness sublayer (RSL), defined as the layer with significant form-induced stresses, stays almost constant. The ensemble-average flows inside the RSL stays close to equilibrium throughout the transient. This is shown by the form-induced perturbations largely scaling with the mean velocity at the edge of the RSL. Inside the RSL, turbulence develops rapidly to the new steady state, accompanied by substantial changes in the Reynolds stress balance. In contrast, the flow above the RSL recovers long after the sublayer is fully developed, without a significant change in Reynolds stress balance. The geometry of the roughness plays an important role in determining the rate of response of turbulence throughout the boundary layer. This work provides detailed explanation of the suppression of reverse transition by surface roughness in response to a mean flow acceleration. [ABSTRACT FROM AUTHOR]

The effects of bed roughness, isolated from those of bed permeability, on the vertical transport processes across the sediment–water interface (SWI) are not well understood. We compare the statistics and structure of the mean flow and turbulence in open-channel flows with a friction Reynolds number of 395 and a permeability Reynolds number of 2.6 over sediments with either regular or random grain packing at the SWI. The regular sediment interface is formed by cubic packing of spheres aligned with the mean-velocity direction. It is shown that, even in the absence of any bedform, the subtle details of the particle roughness alone can significantly affect the dynamics of turbulence and the time-mean flow. Such effects translate to large differences in penetration depths, apparent permeabilities, vertical mass fluxes and subsurface flow paths of passive scalars. The less organized distribution of mean recirculation regions near the interface with a random packing leads to a more isotropic form-induced stress tensor. The augmented wall-normal form-induced fluctuations play a significant role in increasing mixing and wall-normal mass and momentum exchange. [ABSTRACT FROM AUTHOR]

A long-standing problem in turbulence modeling is that the Reynolds stress tensor alone is not necessarily sufficient to characterize the transient and nonequilibrium behaviors of turbulence under arbitrary mean deformation or frame rotation. A more complete single-point characterization of the flow can be obtained using the structure dimensionality, circulicity, and inhomogeneity tensors. These tensors are one-point correlations of local stream vector gradients and carry nonlocal information regarding the structure of the flow field. We explore the potential of these tensors to improve understanding of complex turbulent flows using direct numerical simulation of flows in channels with a smooth wall and a two-dimensional sinusoidal wavy wall. To enforce no-slip and no-penetration conditions at wavy-wall boundaries, an immersed boundary method for the stream vector Poisson equation was adopted within the framework of Stylianou, Pecnik, and Kassinos, "A general framework for computing the turbulence structure tensors," Comput. Fluids 106, 54–66 (2015). The results show that the effects of wall waviness on the inclination and aspect ratio of the two-point velocity correlation near the wall are reproduced qualitatively by their corresponding single-point tensor representations. In the outer layer, good quantitative agreement is achieved for both parameters. Additional observations on the structural changes of turbulence due to wall waviness and their relevance to turbulence modeling with surface roughness are discussed. The findings of this investigation suggest that single-point structure tensors can be appended to the modeling basis for inhomogeneous flows with geometrically complex boundaries, such as rough-wall flows, to develop improved turbulence models. [ABSTRACT FROM AUTHOR]

Turbulence structures in flow over three types of wall roughness: sand-grain, cube roughness and a realistic, multi-scale turbine-blade roughness, are compared to structures observed in flow over a smooth wall in open channel flow at R e τ = 1000 , using direct numerical simulations. Two-point velocity correlations, length scales, inclination angles, and velocity spectra are analysed, and the applicability of Townsend's outer layer similarity hypothesis [Townsend. The structure of turbulent shear flow. Cambridge: Cambridge University Press; 1976] to these parameters was examined. Results from linear stochastic estimation suggest that, near the wall, the quasi-streamwise vortices observed in smooth-wall flow are present in the large-scale recessed regions of multi-scale roughness, whereas they are replaced by a pair of 'head-up, head-down' horseshoe structures in sandgrain and cube roughness, similar to those observed by Talapatra and Katz [Coherent structures in the inner part of a rough-wall channel flow resolved using holographic PIV. J Fluid Mech. 2012;711:161–170]. The configuration of conditional eddies near the wall suggests that the kinematical process of vortices differ for each kind of rough surface. Eddies over multiscale roughness are conjectured to obey a growth mechanism similar to those over smooth walls, while around the cube roughness the head-down horse-shoe vortices of Talapatra and Katz [Coherent structures in the inner part of a rough-wall channel flow resolved using holographic PIV. J Fluid Mech. 2012;711:161–170] may undergo solid-body rotation on top of a cube roughness on account of the strong shear layer, shortening the longitudinal extent of near-wall structure and promoting turbulence production during this process. These results illustrate the sensitivity of turbulence structure to the roughness texture, particularly within the roughness sublayer. [ABSTRACT FROM AUTHOR]

Red (Ho3+:5F5→5I8), green (Ho3+:5S2,5F4→5I8), and blue (Tm3+:1D2→3F4 and 1G4→3H6) upconversion emissions were simultaneously generated in the transparent glass ceramics containing Nd3+/Yb3+/Tm3+/Ho3+:β-YF3 nanocrystals under 796 nm excitation. It was experimentally evidenced that Yb3+ ions acted as the bridging centers to prompt energy transfer from Nd3+ to Tm3+ and Ho3+. With appropriately optimizing the contents and relative ratios of the doped rare earth species, luminescence of various colors, including bright white light, was easily tuned in the glass ceramics. The related upconversion mechanisms were proposed. [ABSTRACT FROM AUTHOR]

Abstract Epidemiological studies have shown that high molecular weight phthalates (HMW) such as diethylhexyl phthalate (DEHP), are associated with hypertension in humans, while low molecular weight phthalates (LMW) such as dibutyl phthalate (DBP), have hardly any impact on the elevation of blood pressure. However, the molecular mechanisms responsible for this difference are not completely understood. In this experiment, mice were exposed to 0.1/1/10 mg/kg/day DEHP and 0.1/1/10 mg/kg/day DBP for 6 weeks, and their blood pressure was monitored using the tail pressure method. The results showed that exposure to DEHP dosages of 1 or 10 mg/kg/day resulted in a sharp increase in blood pressure, while exposure to DBP did not induce any significant changes in blood pressure. Investigating the renin-angiotensin-aldosterone system (RAAS) and NO pathway in mice exposed to DEHP, we found that levels of angiotensin-converting enzyme (ACE) and angiotensin II (AngII) increased with increasing exposure to DEHP, and the expression of nitric oxide synthase (eNOS) and the level of NO decreased. Treatment with ACE inhibitor (ACEI) to block the ACE pathway inhibited the enhancement of RAAS expression, inhibited the increase in blood pressure, and inhibited the decrease in NO levels induced by DEHP. However, the expression of ACE, AngII, AT1R, and eNOS in the DBP treatment groups showed no significant changes. When examining estradiol in vivo, we found that exposure to DBP resulted in a significant increase in the level of estradiol, while exposure to DEHP did not lead to a significant change. When ICI182780 was used to block the estradiol receptors, any increase in the level of NO induced by DBP exposure, was inhibited. These results indicate that exposure to DEHP induces an increase in mouse blood pressure through RAAS, and the different effects of DEHP and DBP on blood pressure are partly due to the different estradiol levels induced by DEHP and DBP. Highlights • Exposure to DEHP induced a sharp increase in blood pressure, while exposure to DBP did not. • Exposure to DEHP induced the enhancement of RAAS expression and inhibited NO signal pathway. • The different effects of DEHP and DBP on BP partly due to the different estradiol levels. [ABSTRACT FROM AUTHOR]

Haptens 2-Methyl-4-(trifluoromethyl)thiazole-5-carboxylic acid and 2,6-Dibromo-4-(trifluoromethoxy)aniline, the two moieties of thifluzamide, were conjugated with carrier proteins for the synthesis of artificial antigens. Two distinct anti-thifluzamide polyclonal antibodies (PAb-1 and PAb-2) were produced from the immunized female Balb/c mice. The indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) in two formats based on the PAbs was developed for thifluzamide analysis. The concentration of 50% inhibition (IC50) of ELISA-1 was 1.39 mg L−1 and its limit of detection (LOD) was 0.082 mg L−1. Meanwhile, ELISA-2 had a similar IC50 of 1.96 mg L−1 and a LOD of 0.074 mg L−1 as ELISA-1. Both the raised PAbs exhibited high specificity to thifluzamide. The recoveries for spiked samples including water and wheat ranged from 72.0% to 128.4%, and the accuracy of ELISA was confirmed by high-performance liquid chromatography. In summary, the ic-ELISA might be a promising tool for simple, sensitive and rapid detection of thifluzamide residues in real samples. [ABSTRACT FROM AUTHOR]

Formaldehyde (FA) is an environmental pollutant and an endogenous product believed to be involved in tumorigenesis. However, the underlying mechanism of observed FA effects has not been clearly defined. Paxillin is a focal adhesion protein that may play an important role in several signaling pathways. Many paxillin-interacting proteins are involved in the regulation of actin cytoskeleton organization, which is necessary for cell motility events associated with diverse biological responses, such as embryonic development, wound repair and tumor metastasis. P53 is important in multicellular organisms, where it regulates the cell cycle and thus functions as a tumor suppressor that is involved in preventing cancer. In this study, we investigated the effects of FA on paxillin–tyrosine phosphorylation and P53 expression in Hela cells by Western blot and immunofluorescence. Western blot analysis revealed that nonlethal concentrations of FA (0.5, 1.0 and 2.0 mM, with the exposure time for 0.5, 1.0 and 2.0 h, respectively) had downregulated paxillin and wild-type p53 genes expression while upregulated paxillin–tyrosine phosphorylation significantly. At the same time, phosphotyrosine at the focal adhesion sites detected by immunofluorescence assay obviously increased in Hela cells incubated with 2.0 mM FA for 2 h. The results suggested that paxillin and p53 genes expression may be involved in FA-related adverse effects and the mechanism may be involved in paxillin–tyrosine phosphorylation. [ABSTRACT FROM AUTHOR]

Bensulfuron methyl (BSM) is widely used for agricultural purposes and has raised health concerns, as well as ecological problems. Immunoassay would be one of the most advantaged measurements compared with traditional methods for BSM detection and measurement. In order to develop indirect competitive enzyme-linked immunoassay (icELISA), the anti-BSM monoclonal antibody (anti-BSM MAb) was produced. For the MAb production, BSM was conjugated to OVA and injected to mice with Freud's adjuvant for immunisation. Antiserum screening has revealed successful immunising. One stable hybridoma cell line (2H1) was obtained through cell fusion between spleen cells of immunised mouse and SP 2/0 cells. The MAb secreted by 2H1 cells was of high affinity and sensitivity, as well as specificity to BSM. Then the protocol of the icELISA and standard curve for BSM measurement was made and examined by controlled application. Significantly, the application has exhibited 96.530%–107.2% recovery of BSM. The produced MAb and established immunoassay may facilitate the measurement of BSM and herein help to ensure food safety and regulate environmental protection. [ABSTRACT FROM PUBLISHER]

To assess the aquatic ecosystem safety of silicon dioxide (SiO2) nanoparticles (NPs), we studied the toxicity of the SiO2NPs and SiO2bulk particles (BPs) using zebrafish. Our results show that the SiO2NPs can significantly affect the development of zebrafish embryos, while there is no obvious effect on survival and development of embryos was found in SiO2BPs exposure group. The content of malondialdehyde (MDA) in zebrafish larvae exposed to the SiO2NPs for 108 hours, increased significantly in dose-dependent manner. These results suggest that the SiO2NPs have toxic effects on the development of zebrafish embryos and the effects could be resulted by oxidative damage. [ABSTRACT FROM AUTHOR]

Abstract: The samples of YBa3B9O18, LuBa3(BO3)3, α-YBa3(BO3)3 and LuBO3 powders have been synthesized by the solid-state reaction methods at high temperature and their X-ray excited luminescent properties were investigated. All the studied materials show a broad emission band in the wavelength range of 300–550nm with the peak centers at about 385nm for YBa3B9O18 and LuBa3(BO3)3, 415nm for α-YBa3(BO3)3 and 360nm for LuBO3 powders, respectively. Even though those compounds have the different atomic structures, they have the common structural feature of each yttrium or lutetium ion bonded to six separate BO3 groups, i.e., octahedral RE(BO3)6 (RE=Lu or Y) moiety. This octahedral RE(BO3)6(RE=Lu or Y) moiety seems to be an important structural element for efficient X-ray excited luminescence of those compounds, as are the edge-sharing octahedral TaO6 chains for tantalate emission. [Copyright &y& Elsevier]

Microplastics (MP) are receiving increased attention as a harmful environmental pollutant, however information on the reproduction toxicity of MP in terrestrial animals, especially mammals, is limited. In this experiment, we investigated the impact of polystyrene microplastics (micro-PS) on the reproductive system of male mice. Healthy Balb/c mice were exposed to saline or to different doses of micro-PS for 6 weeks. The results showed that micro-PS exposure resulted in a significant decrease in the number and motility of sperm, and a significant increase in sperm deformity rate. We also detected a decrease in the activity of the sperm metabolism-related enzymes, succinate dehydrogenase (SDH) and lactate dehydrogenase (LDH), and a decrease in the serum testosterone content in the micro-PS exposure group. We found that micro-PS exposure caused oxidative stress and activated JNK and p38 MAPK. In addition, we found that when N-acetylcysteine (NAC) scavenges ROS, and when the p38 MAPK-specific inhibitor SB203580 inhibits p38MAPK, the micro-PS-induced sperm damage is alleviated and testosterone secretion improves. In conclusion, our findings suggest that micro-PS induces reproductive toxicity in mice through oxidative stress and activation of the p38 MAPK signaling pathways. Image 1 • Micro-PS resulted in a significant decrease in the quantity and quality of sperm in mice. • Micro-PS exposure caused oxidative stress in testes. • Micro-PS exposure activated JNK and P38 MAPK. • Blocking oxidative stress or P38 MAPK can alleviate micro-PS-induced sperm damage. [ABSTRACT FROM AUTHOR]

Turbulence structures in flow over three types of wall roughness: sand-grain, cube roughness and a realistic, multi-scale turbine-blade roughness, are compared to structures observed in flow over a smooth wall in open channel flow at R e τ = 1000 , using direct numerical simulations. Two-point velocity correlations, length scales, inclination angles, and velocity spectra are analysed, and the applicability of Townsend's outer layer similarity hypothesis [Townsend. The structure of turbulent shear flow. Cambridge: Cambridge University Press; 1976] to these parameters was examined. Results from linear stochastic estimation suggest that, near the wall, the quasi-streamwise vortices observed in smooth-wall flow are present in the large-scale recessed regions of multi-scale roughness, whereas they are replaced by a pair of 'head-up, head-down' horseshoe structures in sandgrain and cube roughness, similar to those observed by Talapatra and Katz [Coherent structures in the inner part of a rough-wall channel flow resolved using holographic PIV. J Fluid Mech. 2012;711:161–170]. The configuration of conditional eddies near the wall suggests that the kinematical process of vortices differ for each kind of rough surface. Eddies over multiscale roughness are conjectured to obey a growth mechanism similar to those over smooth walls, while around the cube roughness the head-down horse-shoe vortices of Talapatra and Katz [Coherent structures in the inner part of a rough-wall channel flow resolved using holographic PIV. J Fluid Mech. 2012;711:161–170] may undergo solid-body rotation on top of a cube roughness on account of the strong shear layer, shortening the longitudinal extent of near-wall structure and promoting turbulence production during this process. These results illustrate the sensitivity of turbulence structure to the roughness texture, particularly within the roughness sublayer. [ABSTRACT FROM AUTHOR]

We present the results of direct and large-eddy simulations of spatially developing boundary layers subjected to favorable pressure gradient, strong enough to cause reversion of the flow towards a quasi-laminar state. The numerical results compare well with experimental data. Visualization of the flow structures shows the well-known stabilization of the streaks, the re-orientation of outer layer vortices in the streamwise direction, and the appearance of turbulent spots in the re-transition region. Both instantaneous visualizations and turbulent statistics highlight the significant damping of wall-normal and spanwise fluctuations. The fast component of the pressure fluctuations appears to be the main driver of this process, contributing to reduce pressure fluctuations and, as a consequence, the energy redistribution term in the Reynolds stress budgets. The streamwise stresses, in whose budget a separate production term plays a role, do not decay but remain frozen at their upstream value. The decrease of wall-normal and spanwise fluctuations appears to be the main cause of the inner-layer stabilization, by disrupting the generation and subsequent growth of streaks, consistent with various models of the turbulence-generation cycle proposed in the literature. The outer layer seems to play a passive role in this process. The stretching and reorientation of the outer-layer vortices results in a more orderly and organized structure; since fewer ejections occur, the inner layer does not break this re-organization, which is maintained until re-transition begins. [ABSTRACT FROM AUTHOR]

Formaldehyde (FA) is a human leukemogen. Since there is a latency period between initial FA exposure and the development of leukemia, the subsequent impact of FA on hematopoietic stem or progenitor cells (HSCs/HPCs) in post-exposure stage is crucial for a deep understanding of FA-induced hematotoxicity. BALB/c mice were exposed to 3 mg/m 3 FA for 2 weeks, mimicking occupational exposure, and were monitored for another 7 days post-exposure. Meanwhile, we included benzene (BZ) as a positive control, separately and together with FA because co-exposure occurs frequently. After 7-day recovery, colonies of progenitors for CFU-GM and BFU-E, and nucleated bone marrow cells in FA-exposed mice were comparable to controls, although they were significantly reduced during exposure. Levels of reactive oxygen species (ROS) and 8-hydroxy-2′-deoxyguanosine (8-OHdG) in CFU-GM and BFU-E from FA-exposed mice were higher than controls, although the increase in 8-OHdG was not significant. Granulocyte-macrophage colony stimulating factor (GM-CSF) level in the FA group was lower than controls, but the expression level for the receptor was not upregulated. It suggests that HSCs/HPCs in FA-exposed mice respond to a small amount of GM-CSF and proliferate rapidly, which may cause a possible risk of expansion of abnormal stem/progenitor cell clones. FA co-exposure with BZ was more potent for promoting CFU-GM formation and inducing ROS in BFU-E and 8-OHdG in CFU-GM during the post-exposure period. The compensation of myeloid progenitors with elevated ROS and 8-OHdG may lead to a risk of transforming normal HSCs/HPCs to leukemic stem/progenitor cells. Thus, co-exposure may pose a greater leukemia risk. [ABSTRACT FROM AUTHOR]

Abstract: Dibutyl phthalate (DBP) is mainly taken up by the general population from food intake. To estimate intake of phthalates, determining distribution and accumulation of DBP in biological materials was a critical need. In this work, we set up two novel approaches with a monoclonal antibody specific to DBP to determine the distribution and accumulation of DBP in vivo. The contents of DBP in liver, kidney, stomach and testes were detected by immunofluorescence assays and indirect competitive ELISA. This data give directly evidence that indicates the distribution and accumulation of DBP in vivo. Double-label immunofluorescence assay provides with a visual approach to determination of the distribution and accumulation of DBP. It indicated that DBP accumulated in subcutaneous tissue such as sweat gland, hair follicle. Both of immunofluorescence assay and ELISA can be used to detect the content of DBP in biological materials. Our assays showed that DBP accumulated in viscera being rich in fat, such as liver, kidney and could overcome physiological barriers to penetrate testes. The date suggested that the accumulations of DBP exposed through dermal route were less than that of oral route and most of DBP was metabolized in 2 or 3days. [Copyright &y& Elsevier]

Abstract: The crystal structure of Lu2WO6 was determined from Rietveld refinement of X-ray powder diffraction data. It crystallizes in the monoclinic system belonging to space group P2/c (No.13) with lattice parameters: a =7.5180(1)Å, b =5.2675(1)Å, c =11.2245(2)Å, β =104.61(0)°, V =430.14(11)Å3, Z =4. The conventional R indices obtained are R p =0.090, R wp =0.119 and R B =0.075. The infinite chain comprised of Lu(2)O8 dodecahedra and Lu(3)O7 decahedra makes up the layer A, and the infinite straight chain is built of four-ring of polyhedra in which the WO6 and Lu(1)O8 groups alternate in layer B, finally, this structure is formed by stacking of these two layers with edge-shared. The X-ray and UV excited luminescence properties of Eu3+ and Pr3+ in Lu2WO6 were investigated: Eu3+ shows high luminescent efficiency in emitting red light, and Pr3+ is less efficient in emitting orange light. The luminescent mechanism of Eu3+ and Pr3+ in the matrix of Lu2WO6 is much different. [Copyright &y& Elsevier]