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To address the issue of accuracy in Simultaneous Localization and Mapping (SLAM) for forested areas, a novel point cloud adaptive filtering algorithm is proposed in the paper, based on point cloud data obtained by backpack Light Detection and Ranging (LiDAR). The algorithm employs a K-D tree to construct the spatial position information of the 3D point cloud, deriving a linear model that is the guidance information based on both the original and filtered point cloud data. The parameters of the linear model are determined by minimizing the cost function using an optimization strategy, and a guidance point cloud filter is subsequently constructed based on these parameters. The results demonstrate that, comparing the diameter at breast height (DBH) and tree height before and after filtering with the measured true values, the accuracy of SLAM mapping is significantly improved after filtering. The Mean Absolute Error (MAE) of DBH before and after filtering are 2.20 cm and 1.16 cm; the Root Mean Square Error (RMSE) values are 4.78 cm and 1.40 cm; and the relative RMSE values are 29.30% and 8.59%. For tree height, the MAE before and after filtering are 0.76 m and 0.40 m; the RMSE values are 1.01 m and 0.50 m; the relative RMSE values are 7.33% and 3.65%. The experimental results validate that the proposed adaptive point cloud filtering method based on guided information is an effective point cloud preprocessing method for enhancing the accuracy of SLAM mapping in forested areas. [ABSTRACT FROM AUTHOR]

• A new synthetic routes of Cu 2−x Se/CuTi CE has been proposed. • Cu 2−x Se/CuTi CE is fabricated by sacrifice template method. • The QDSCs based on the Cu 2−x Se/CuTi CE achieves the PCE of 6.25%. • The enhanced photovoltaic performance could be attributed to the improving electrocatalytic activity. • The Cu 2−x Se/CuTi CE shows excellent stability in polysulfide electrolyte. An efficient and simple strategy is designed for the synthesis of Cu 2−x Se with two different morphology, including networks nanostructure and nanosheets structure, based on Ti substrate using a sacrificial template method (CuTi 2 S 4 and Cu). The corresponding Cu 2−x Se/CuTi CE and Cu 2−x Se/Cu CE could be applied as counter electrodes (CE) for quantum dot sensitized solar cells (QDSCs). As a result, the cell fabricated by Cu 2−x Se/CuTi-4 CE exhibits a photoelectric conversion efficiency (PCE) of 6.25% under 1 sun (100 mW/cm2) illumination as compared to that of Cu 2−x Se/Cu CE (4.83%). According to transient photocurrent (TPC) result, the improving photovoltaic performance could be attributed to the improving electrocatalytic activity towards polysulfide electrolyte as compared to Cu 2−x Se/Cu CE. These results are in accordance with the EIS analysis and Tafel polarization curve results for symmetrical cell. In addition, the outstanding stability of Cu 2−x Se/CuTi CE could be further proved by cyclic voltammetry (CV) test. In conclusion, the Cu 2−x Se/CuTi CE could be a promising material and the applications in solar cells. [ABSTRACT FROM AUTHOR]

Field investigations were conducted on a decabrominated diphenyl ether (BDE-209) manufacturing plant and a decabromodiphenyl ethane (DBDPE) manufacturing plant, and worker exposure to polybrominated diphenyl ethers (PBDEs) or DBDPE was assessed. Workshop air was collected and tested to measure levels of external exposure to corresponding chemicals via air inhalation. Paired human serum and urine samples taken from 202 workers were tested to assess levels of internal BFR exposure. Levels of BDE-209 in air for the BDE-209 plant ranged from 10.6 to 295 μg m−3, accounting for at least 99% of the total PBDEs in the workshop air, and those of DBDPE in air samples from the DBDPE plant ranged from 12.7 to 435 μg m−3. Maximum estimated daily intakes (EDIs) of BDE-209 and DBDPE accumulated via air inhalation exceeded the corresponding RfD level recommended by the U.S. Environmental Protection Agency, indicating that for some workers, occupational exposure is likely to create significant health problems. The levels of BDE-209 measured in serum taken from BDE-209 workers ranged from 0.202 to 57.1 μg g−1 lw, and those of DBDPE in serum taken from DBDPE workers ranged from 0.087 to 54.4 μg g−1 lw. These values are several orders of magnitude higher than those detected in general areas and e-waste recycling sites. BDE-209 and DBDPE were detected in all of the urine samples with median levels of 1.12 and 8.6 ng mL−1, respectively, and levels of BDE-209 and DBDPE in the urine were significantly and positively correlated with those observed in the serum. • Exposure of occupational workers to PBDEs or DBDPE from BFR plants was assessed. • Exposure to BDE-209 or DBDPE via workshop air would raise significant health risks. • Extremely high levels of PBDEs or DBDPE were detected in serum from the workers. [ABSTRACT FROM AUTHOR]

This paper reports a one-step hydrothermal method of in-situ growing copper selenide (CuSe) nanoparticles on the 2D materials-MXene (Ti 3 C 2) nanosheets to form CuSe/Ti 3 C 2 composite with three-dimensional structure. The CuSe/Ti 3 C 2 slurry prepared via a solvothermal method was screen-printied onto graphite sheet to form a counter electrode (CE) in quantum dot-sensitized solar cells (QDSCs). The CuSe/Ti 3 C 2 CE shows the better electrical conductivity for electron transfer, and a larger specific surface area to provide more active sites for polysulfide electrolyte reduction, as compared to the pristine CuSe CE and Ti 3 C 2 CE. Hence, the device with CuSe/Ti 3 C 2 -30 mg CE achieves an efficiencies of 5.12%, which much better than that of CuSe CE (3.47%) and Ti 3 C 2 CE (2.04%). The symmetrical dummy cells consisting of two CEs are further designed to confirm the best electrocatalytic activity and the excellent stability of composite CE towards polysulfide electrolyte. Therefore, CuSe/Ti 3 C 2 is very promising as CE for QDSCs and this strategy provides a facile route for the design of the composite with MXene as a CE for QDSCs. [ABSTRACT FROM AUTHOR]

Tire force distribution with the consideration of practical constraints is a key part of automatic driving. This paper is intended to improve the operational capability of the vehicle under low friction coefficient. The speed and front wheel angle are restricted within a specific range caused by the limitation of executable drive space, which is defined as an input constrained problem of the nonlinear system. The hierarchical design concept is adopted in this paper, including algorithms of both control and allocation to determine the driving performance cooperatively. The methodology of multi-input and multi-output sliding mode control (MIMO SMC) is applied in the high-level controller to guarantee the vehicle system stable. Confronted with circumstances that the vehicle may be seriously unstable due to longitudinal forces and lateral forces beyond the feasible region in the friction circle, the scheme of dynamic adjustment of control target is provided owing to there is no reasonable solution for tire force distribution in the low-level controller. The coefficients of reconstruction and attenuation are introduced to reconstruct the optimized controller and weaken inputs of the closed loop system, respectively. The simulation results verify that the proposed design can redistribute generalized forces and moments between the wheels especially for the poor road condition. [ABSTRACT FROM AUTHOR]

Deep learning is vulnerable to backdoor poisoning attacks in which an attacker can easily embed a hidden backdoor into a trained model by injecting poisoned samples into the training set. Many prior state-of-the-art techniques for detecting backdoor poisoning attacks are based on a potential separability assumption. However, current adaptive poisoning strategies can significantly reduce 'distinguishable behavior', making most prior state-of-the-art techniques less effective. In addition, we note that existing detection methods are not practical for multidomain datasets and may leak user privacy because they require and collect clean samples. To address the above issues, we propose a multidomain active defense approach that does not use clean datasets. The proposed approach can generate diverse clean samples from different domains and decouple neural networks round by round using clean samples to disassociate features and labels, making backdoor poisoned samples easier to detect without fitting clean samples. We demonstrate the advantage of our approach through an extensive evaluation of CIFAR10, CelebA, MNIST & MNIST-M, MNIST & USPS & MNIST-M, MNIST & USPS & SVHN and CIFAR10 & Tiny-ImageNet. • The method identifies backdoor-poisoned samples in multidomain datasets. • The method presents an MI generation module that does not depend on clean datasets. • ALL-to-ALL decoupling training to decouple association between features and labels. • Extensive experiments demonstrate our effectiveness across multidomain datasets. [ABSTRACT FROM AUTHOR]

A series of nano-spindly BiVO 4 and Ag-BiVO 4 were synthesized by a simple solvothermal method. X-ray photoelectron spectroscopy (XPS) and high resolution electron microscopy (HRTEM) analysis indicated that the chemical state of the Ag particles was metallic Ag. Their photocatalytic activities were evaluated by the decolorization of rhodamine B (RhB) under visible light irradiation ( λ > 420 nm). The research of photoinduced charge properties of samples studied by surface photovoltage spectroscopy (SPS) and electric field-induced surface photovoltage spectroscopy (FISPS) measurement system and the results indicated that the existence of Ag attained the enhancement of photoinduced charge carriers’ separation. This was thought to be responsible for the higher efficient photocatalytic activity of Ag-BiVO 4 in the degradation of RhB. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) BiVO4/Bi2WO6 composite microspheres with enhanced visible-light (λ ＞ 420 nm) photodegradation activity of methylene blue (MB) were synthesized by a simple, one-pot, template-free solvothermal method. A mixture of ethylene glycol (EG) and H2O (volume ratio of EG-H2O was 1 : 1) was used as the solvent. To investigate the relationship between structure and photocatalytic performance, the as-synthesized samples were characterized by XRD, FESEM, HRTEM, UV-vis DRS, SPS and TPV. Structural characterizations indicated that the composite nanostructure mainly consisted of two single-crystal phases, which were BiVO4 and Bi2WO6. In addition, a possible growth mechanism of this microsphere composite and the separation process of photoinduced charge carriers in the heterojunction are discussed. [ABSTRACT FROM AUTHOR]

In order to improve kinematic single epoch positioning accuracy and realize real-time processing, the article presents a precise kinematic single epoch positioning algorithm using moving window wavelet denoising. Firstly, we obtain the observation residuals by using the conventional single epoch method and improve end effect by data extending a part of the current epoch. Secondly, we denoise the current epoch observation residuals using a window wavelet, and achieve an adaptive selection of the wavelet decomposition level for denoising through cross-validation. Finally, we achieve final positioning accuracy using the clean observations, after denosing. Comparing the proposed method with conventional single epoch positioning, experimental results show that positioning accuracy has been improved greatly for different motions. The results were consistent with those from wavelet post processing. [ABSTRACT FROM AUTHOR]

The mesenchymal stem cells (MSCs) derived from amniotic fluid (AF) have become an attractive stem cells source for cell-based therapy because they can be harvested at low cost and avoid ethical disputes. In human research, stem cells derived from AF gradually became a hot research direction for disease treatment, specifically for their plasticity, their reduced immunogenicity and their tumor tropism regardless of the tumor size, location and source. Our work aimed to obtain and characterize human amniotic fluid mesenchymal stem cells (AFMSCs) and detect their ovarian cancer tropsim in nude mice model. Ten milliliters of twenty independent amniotic fluid samples were collected from 16-20 week pregnant women who underwent amniocentesis for fetal genetic determination in routine prenatal diagnosis in the first affiliated hospital of Harbin medical university. We successfully isolated the AFMSCs from thirteen of twenty amniotic fluid samples. AFMSCs presented a fibroblastic-like morphology during the culture. Flow cytometry analyses showed that the cells were positive for specific stem cell markers CD73,CD90, CD105, CD166 and HLA-ABC (MHC class I), but negative for CD 45,CD40, CD34, CD14 and HLA-DR (MHC class II). RT-PCR results showed that the AFMSCs expressed stem cell marker OCT4. AFMSCs could differentiate into bone cells, fat cells and chondrocytes under certain conditions. AFMSCs had the high motility to migrate to ovarian cancer site but didn’t have the tumorigenicity. This study enhances the possibility of AFMSCs as drug carrier in human cell-based therapy. Meanwhile, the research emphasis in the future can also put in targeting therapy of ovarian cancer. [ABSTRACT FROM AUTHOR]

Purpose: Amniotic fluid mesenchymal stem cells (AF-MSCs) are promising candidates for cell-based therapy. This review presents a comprehensive overview of the features and therapeutic applications of these cells. Methods: This is a literature review combined with experience of practice. Conclusion: Although the long-term risks of AF-MSCs require further investigation, these cells are increasing in popularity in the fields of regenerative medicine and targeting therapy because of their unique properties. [ABSTRACT FROM AUTHOR]

Highlights: [•] CdS QDs were attached to TiO2 nanorod arrays via a one-step in situ hydrothermal route. [•] GSH molecule could link the CdS QDs onto the surface of TiO2 nanorods. [•] The photoanode exhibited a maximum η of 0.278% with the J sc of 1.95mAcm−2. [ABSTRACT FROM AUTHOR]

Abstract: Ag–ZnO nanorods with enhancement in UV light photoelectric gas-sensing response properties were synthesized by a facile two-step process and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution electron microscope (HRTEM) and UV–vis diffuse reflectance spectroscopy (UV–vis DRS). The results revealed that Ag nanoparticles have decorated the surface of ZnO nanorods successfully. Formaldehyde (HCHO) sensing properties of sensors based on the Ag–ZnO nanorods were also investigated under 370nm light irradiation at room temperature with the assistance of surface photocurrent technique. It was found that the as-prepared Ag–ZnO nanorods showed excellent gas-sensing property that the gas response to 5 and 40ppm formaldehyde can reach to 9.4% and 119.8% under 370nm light irradiation at room temperature, respectively. To better understand the reason for the enhanced gas-sensing properties of Ag–ZnO, the separation and transfer behavior of the photogenerated charges were characterized by means of surface photovoltage and phase spectra. The results indicated that an electronic interaction between Ag and ZnO formed. Ag, as electron acceptor, effectively promoted the charge separation and transfer ability and, at the same time, inhibited the recombination of photogenerated charge carriers in ZnO, thus the Ag–ZnO nanorods had a high gas-sensing response to HCHO at room temperature. [Copyright &y& Elsevier]

Abstract: Fe-doped ZnO are fabricated by hydrothermal method. The influence of the annealing temperature on structural and photoelectric property was studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV–vis diffuse reflectance spectra (UV–vis DRS). Visible light-illumination room-temperature gas sensing to formaldehyde based on Fe-doped ZnO annealed at different temperatures was subsequently investigated by the surface photocurrent spectra and gas sensor characterization system, respectively. Accompanying with increasing annealing temperature from 400°C to 600°C, the response to formaldehyde was enhanced due to the increase in crystal quality and active sites on the surface of Fe-doped ZnO. However, when the annealing temperature goes over 700°C, the phase of ZnFe2O4 was observed from XRD pattern. The existence of ZnFe2O4 hindered the transfer of photo-generated carriers and decreased the amount of surface active sites. As a result, the photoelectric gas response for formaldehyde was weaken to some extent. Our results demonstrated that annealing temperature is a very important parameter in the determination of the sensitivity of photoelectric gas sensing based on Fe-doped ZnO. [Copyright &y& Elsevier]

Abstract: Different morphologies of monoclinic BiVO4 with smaller size were hydrothermal synthesized by simply adjusting the amount of surfactant (polyvinyl pyrrolidone PVP K30) added. The detailed field emission scanning electron microscope (FESEM) analysis revealed that the amount of PVP added could significantly affect the morphology and size of BiVO4. Their photocatalytic activities were evaluated by the decolorization of methylene blue (MB) aqueous solution under visible-light irradiation (λ >400nm), and the as-prepared sample with well-assembled flower-like morphology showed a much higher photocatalytic activity due to larger specific surface area and higher separation efficiency of photo-induced carriers. The relationship between the behavior of photo-induced carriers and photocatalytic activity was studied using the surface photovoltage spectroscopy (SPS) and corresponding phase spectra. [Copyright &y& Elsevier]

Abstract: Carbon-doped anatase TiO2 was prepared by a facile hydrothermal process without adding additional carbon source. The as-prepared sample shows highly efficient photocatalytic activity, which only requires 4min and is about 11 times higher than that of Degussa P25 TiO2 in degradation of methyl orange (MO) dye under UV light irradiation. Moreover, a highly visible-light activity is also observed. UV–vis diffuse reflectance spectra and X-ray photoelectron spectroscopy confirm that the carbon atoms are incorporated into the interstitial positions of TiO2 lattice and form a strong interaction with titanium atoms and extend photoresponding range to 700nm. Surface photovoltage spectra (SPS) and transient photovoltage (TPV) suggest that the presence of interstitial carbons induce several localized occupied states in the gap, enhance the separation extent and restrain the recombination of the photo-induced electron and hole carriers in TiO2. [Copyright &y& Elsevier]

Abstract: In this study TiO2 nanotube arrays were fabricated by potentiostatic anodization of titanium sheet. The X-ray diffraction (XRD) pattern and field emission scanning electron microscopy (FE-SEM) image indicated the TiO2 nanotube arrays were of pure anatase form and highly ordered. The properties of the photo-generated charges in the nanotube arrays were investigated by transient photovoltage (TPV) technique and surface photovoltage (SPV) technique based on lock-in amplifier with dc bias, in comparison with the commercial powder derived film. The separation processes of the photo-induced charges in the system of TiO2 nanotubes on Ti have been demonstrated to be correlated with the incident light intensity, surface trapping states, and the interfacial electric field between Ti and TiO2. The results also show that the highly ordered nanotube film could generate much stronger SPV responses under external electric field than the commercial powder derived film. [Copyright &y& Elsevier]

Abstract: A visible-light-induced gas sensing element based on the heterostructures of CdS nanoparticles (NPs)/ZnO microcrystals has been successfully developed. Commercial ZnO microcrystals were coated with CdS nanoparticles by a sonochemical method to form the heterostructures. Compared with native CdS NPs, the as-obtained CdS NPs/ZnO showed enhanced photocurrent intensity. And the heterostructures-based element exhibited an excellent performance of photoelectric gas sensing to formaldehyde induced by visible-light. Moreover, the photocurrent intensity and sensitivity to formaldehyde were controllable by tuning the amount of CdS NPs attached on the surface of ZnO microcrystals. A possible explanation on the sensing mechanism has been proposed. In addition, the gas sensing element possessed good reproducibility. Our results demonstrate that the heterostructures of CdS NPs/ZnO is an efficient and promising material for visible-light-induced photoelectric gas sensors working at room temperature. [Copyright &y& Elsevier]

Abstract: In this article, ZnO nanoribbons were prepared by multi-components precursor self-assembled method, and the characteristic of photoelectric gas sensing of the nanoribbons was investigated on exposure of oxygen and water environments by surface photocurrent technique. The results showed that surface photocurrent intensity (SPI) was enhanced after oxygen and water adsorption. This increase of SPI was attributed mostly to the improvement of carriers-generating efficiency. And the mechanism was discussed in detail. [Copyright &y& Elsevier]

Abstract: Water-soluble anatase TiO2 nanocrystals (NCs) were synthesized by a simple sol–gel method. The reaction time is greatly reduced even under mild conditions. High-resolution transition electron microscopy (HRTEM), X-ray diffraction (XRD) and UV–vis were used to characterize the synthesized NCs and proved that the NCs are anatase phase and about 2 nm with near spherical shape. Surface photovoltage spectroscopy (SPS) experiments show that the synthesized anatase NCs have good photovoltaic properties compared with that of poly(vinyl pyrrolidone) (PVP) coated NCs synthesized by the similar method. [Copyright &y& Elsevier]

Abstract: A well-aligned nanorods array of ZnO was chemically grown on conductive ITO substrate at low temperature. The photogenerated charges at surface and interface were examined by surface photovoltage techniques based on both Kelvin probe and lock-in amplifier with dc bias. The photovoltage response bands related to band-to-band transition and bound excitons were discriminated. We demonstrated the spectrum-dependent transfer characteristic of photogenerated charges at the surface of ZnO nanorods array and the interface between ZnO and ITO. [Copyright &y& Elsevier]

Abstract: The electronic structure and photo-induced charge carriers transport have been studied in N,N-dimethylperylene-3,4,9,10-dicarboximide (Me-PTCDI) films evaporated on ITO substrate using surface photovoltage (SPV) technique. For the Me-PTCDI film with the thickness of 456nm, with changing the illumination geometry, the amplitudes as well as the phases of the SPV response bands at the wavelength where Me-PTCDI strongly absorbs significantly changed, while those of the SPV response bands at the wavelength where Me-PTCDI weakly absorbs hardly changed. It was explained based on the different absorption lengths of Me-PTCDI at different wavelengths. The experiment results suggest that the photo-induced charge carriers generated at the surface and the interface region are separated by the action of the built-in electric field and move in the opposite directions. From the dependence of the work function on the film thickness, it is inferred that the interface and surface are all depleted with the interface space charge region extending to be about 200nm. In addition, it is found that an acceptor state at 0.1eV above the valence band exists at the surface as well as at the interface. [Copyright &y& Elsevier]

Abstract: An original photoelectric gas sensor, fabricated by Ru(dcbpy)2(NCS)2 (dcbpy=2,2′-bipyridyl-4,4′-dicarboxylate)(RuN3)-sensitized ZnO on a comb-like electrode by surface photocurrent technique with excitation of visible light (545nm), is presented for CO and O2 detection at room temperature. The surface photocurrent (I SPC) of a sample can be dramatically enhanced and diminished depending on the properties of the gases. As a reductive gas, CO can make I SPC increase and the sensor response is linear to the change in CO concentration with a detection limit of 0.62Torr. However, I SPC decreases upon O2 adsorption, since it can capture electrons from the surface. There is no linear dependency between I SPC and concentration of O2. In this article a microscopic mechanism of the photoelectric gas sensor has also been discussed in detail. This research should be valuable for the practical application of the ZnO gas sensor. [Copyright &y& Elsevier]

Abstract: The interface and the related electronic properties in n-Al0.35Ga0.65N/GaN heterostructure were studied non-destructively by the spectral and transient photovoltage (PV) technique. A defect level as recombination center was observed in the buffer layer of GaN at the side close to the substrate. It was found that the GaN layer of 3 μm was completely depleted owing to the formation of two-dimensional electron gas. When the sample was illuminated at the front or the back side, with a laser radiation of 355 nm, the electron-hole pairs were generated in GaN layer and then separated there. By the action of the electric field in GaN layer, the holes moved to the substrate, while the electrons moved to the AlGaN/GaN interface. In the PV transients under the front illumination, a fast and a slow component, related to the initiative separation of the electron-hole pairs and the drift of the resultant holes, respectively, were observed. At higher illumination intensities, the bimolecular recombination happened to the fast component, while in that period of time it did not to the slow one owing to the long separation distance between the electrons and the holes. [Copyright &y& Elsevier]

Abstract: The degeneration of energy level of α, β, γ, δ-tetrahydroxylphenylporphyrin (THPP) and red shift of the photovoltage peaks of THPP are observed as the size of nano-TiO2 decreasing using surface photovoltage (SPV) technique, while that of α, β, γ, δ-tetraphenylporphyrin (TPP) have little change. The reason for that is the existence of hydroxyls of THPP, which interact with the surface of nano-TiO2. This difference was also demonstrated by IR spectrum. [Copyright &y& Elsevier]

In this paper, ZnO nanoparticles were prepared by a sol–gel method and sensitized by azo pigment (4,4′-2-{N-[β-hydroxyl-γ-(ρ-nitroanilino)naphthyl]}azodiphenyl). Measurements of surface photocurrent by comb-like electrode and He–Ne laser and gas adsorption were performed on the ZnO/azo system. The process of photoinduced charge transport from excited dyes to nanocyrstalline ZnO was studied by surface photocurrent response (SPR). We have also discussed different effects of water and oxygen as gas adsorbates on SPR. Such a research should be valuable for the practical application of ZnO nanoparticles to semiconductor gas sensors. [Copyright &y& Elsevier]

In this study, surface photovoltages of titanyl phthalocyanine (TiOPc) and chloroaluminum phthalocyanine (AlClPc) were explored using surface photovoltage spectrum (SPS) technique and field-induced photovoltage spectrum (FISPS) technique. The experimental results show that in the region of 300–800 nm both the metallophthalocyanines give two surface photovoltage response bands corresponding to Soret-band (300–420 nm) and Q-band (500–800 nm), respectively, with Bethe splitting of Q-band. It was experimentally confirmed that the two bands of TiOPc and AlClPc result from electron transition of the same type, π–π* transition. From the results of FISPS it was inferred that TiOPc has p-type character and AlClPc has n-type character. It is coincided with the result of the optimal phase of SPV response. Also it was found that the generation efficiency of photocarriers for TiOPc was nearly not affected by the alternation of the sign of the external electrical field. It is different from AlClPc. Since the precursor of photogenerated free carrier for TiOPc is known to be of charge-transfer state, this observation should be an indication that the precursor for AlClPc has an other than the charge-transfer state. [Copyright &y& Elsevier]

The high demand for pressure devices with miniaturization and a wide bearing range has encouraged researchers to explore new high-performance sensors from different approaches. In this study, a sensitive element based on graphene in-plane compression properties for realizing pressure sensing is experimentally prepared using microelectromechanical systems (MEMS) fabrication technology; it consists of a 50 µm thick, 1400 µm wide square multilayer component membrane and a graphene monolayer with a meander pattern. The prepared sample is extensively characterized and analyzed by using various techniques, including atomic force microscopy, Raman spectroscopy, infrared spectroscopy, X-ray photoelectron spectroscopy, COMSOL finite element method, and density functional theory. The sensing performance of the new pressure sensor based on the sensitive element are obtained by theoretical analysis for electromechanical measurements of the sensitive element before and after low-temperature annealing in atmosphere. Results demonstrate that atmospheric annealing at 300 °C enhances the pressure sensing sensitivity by 4 times compared to pristine graphene without annealing, which benefits from the desorption of hydroxyl groups on the graphene surface during annealing. The sensitivity is comparable and even better than that of previous sensors based on graphene in-plane properties. Our results provide new insights into realizing high-performance MEMS devices based on 2D sensitive materials. [ABSTRACT FROM AUTHOR]

The present study describes a two-step synthesis process for the cobalt complex of tetra-2,3-(5,6-di-tert-butyl-pyrazino) porphyrazine (tBu-TPyzPzCo). The product was ultrasonically impregnated onto carbon black (CB) to prepare a supported catalyst (tBu-TPyzPzCo/CB). We built a split photoelectric catalytic device to test the performance of photocatalytic, electrocatalytic and photoelectrocatalytic degradation of partially hydrolyzed polyacrylamide (HPAM). The results confirm that HPAM exhibited more efficient degradation in the presence of a supporting catalyst using the photoelectrocatalytic process than by photocatalytic or electrocatalytic oxidation—or even the sum of the two in saline water. The photoelectrocatalytic reaction confirmed that the process conforms to quasi-first order reaction kinetics, while the reaction rate constants were 6.03 times that of photocatalysis and 3.97 times that of electrocatalysis. We also compared the energy consumption of the three processes and found that the photoelectrocatalytic process has the highest energy efficiency. [ABSTRACT FROM AUTHOR]

Abstract: Monodisperse Ag/Anatase TiO2 core–shell nanoparticles were synthesized by a simple solvothermal method. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) measurements confirm that the as-synthesized nanoparticles have the core–shell structure and TiO2 shell is anatase phase. Interestingly, the photocatalytic ability of the as-synthesized nanoparticles for degrading alizarin red (AR) is greatly increased compared with that of Dessuga P25. [Copyright &y& Elsevier]

Composite counter electrode Cu 2 S/Cu 2-x Se nanosheets based on brass are fabricated by an in situ inward etching method using Cu(OH) 2 nanotubes as a template. Due to superior electrocatalytic activity towards the polysulfide electrolyte, the quantum dot-sensitized solar cells constructed with Cu 2 S/Cu 2-x Se counter electrodes deliver a considerable power conversion efficiency of 6.10% under 1 sun illumination, which is a 22% enhancement compared to that of Cu 2 S/brass (5.00%). According to the results of BET testing, solid-state J-V measurements and transient photocurrent measurements, the enhanced electrocatalytic activity is attributed to two aspects: one is the larger surface active area, which provides more active sites for the electrolyte, and the other is the formation of a p-p heterojunction for more effective electron transfer in the counter electrode. In addition, the band energy structure of the Cu 2 S/Cu 2-x Se heterojunction is further investigated to understand the behavior of interfacial electron transfer. Finally, the outstanding electrochemical catalytic activity and stability of the Cu 2 S/Cu 2-x Se counter electrode are proved by electrochemical impedance spectroscopy, Tafel polarization and cyclic voltammetry results for symmetric dummy cells, demonstrating that the Cu 2 S/Cu 2-x Se composite is a desirable material as a counter electrode for quantum dot-sensitized solar cells. Image 1 • Cu 2 S/Cu 2-x Se CEs are fabricated by in-situ inward etching method. • The QDSCs based on the Cu 2 S/Cu 2-x Se CE achieves the PCE of 6.10%. • Two reasons are taken into account for the enhanced Photovoltaic performance. • The energy band structures of heterojunction is investigated in composite CE. • The CuSe/Cu x S CEs show excellent stability in polysulfide electrolyte. [ABSTRACT FROM AUTHOR]

The diversity of the carrier transport mechanism in the resistive switching process remains a significant obstacle for the design and application of resistive random access memory (RRAM) devices. In this study, the influence of annealing on the dielectric properties of the Ti/HfOx/Pt RRAM device and its associated carrier transport mechanism is investigated. The results reveal that the current conduction in both annealed and unannealed devices is primarily attributed to grain boundary (GB) relaxation, with only the GB acting as a depletion layer that induces dielectric relaxation. Furthermore, annealing decreases the interfacial polarization and changes the relaxation time at the GB. In addition, the charge carriers exhibit nearest‐neighbor hopping conduction at a higher temperature in Ti/HfOx/Pt RRAM devices, whereas variable‐range‐hopping conduction occurs at lower temperatures. Long‐range charge carrier transport also plays a significant role in the conduction process. To offer a deeper understanding of the conduction processes in the Ti/HfOx/Pt RRAM device, a carrier transport model is proposed, which provides valuable insights into the intricate mechanisms governing conduction in these devices. [ABSTRACT FROM AUTHOR]

Supercapacitors often deliver a significantly high-power density with a long cycling life but low energy density. An exceedingly promising approach is to construct asymmetric supercapacitors (ASCs) reconciling the compromise between power density and energy density. However, ASCs combining transition metal oxides (TMOs) and activated carbon (AC) struggle to improve energy density due to a vast difference in their specific capacitance. To cross this hurdle, we first proposed a new strategy to construct the ASCs with α-MoO3 as the anode and conductive polymer polypyrrole (PPy) as the cathode. The remarkable features of α-MoO3, including its layered structure and ultra-high specific capacitance, along with the stability and fast charge–discharge ability of PPy, have contributed significantly to the augmentation of power density and energy density in ASCs. Taking advantage of these bright features, the operation voltage for α-MoO3//PPy is effectively expanded to 2.0 V, exhibiting a high energy density of 25.9 W h kg−1 at 1538 W kg−1. Furthermore, the energy density presented a remarkable recovery rate, reaching 91.04% of its initial state after undergoing full rate tests. These conclusions reveal that the construction of α-MoO3//PPy can effectively enhance the energy density and power density of supercapacitors. [ABSTRACT FROM AUTHOR]

Carbon nitride with high specific surface area (CN-HA) and improved crystallinity (CN-HC) were rationally designed as probe catalysts to verify the dominant role of crystallinity in enhanced light harvesting efficiency and photocatalytic hydrogen reduction. [Display omitted] Mass transfer enhancement and crystallinity engineering are two prevailing technologies for photocatalyst modification. However, their relative effectiveness in enhancing photocatalytic activity remains unclear due to the lack of rational probing catalysts. In this study, we synthesized two distinct carbon nitride (C 3 N 4) catalysts: one with a high specific surface area (CN-HA) and the other with improved crystallinity (CN-HC). These catalysts served as probes to compare their respective impacts on photocatalytic activities. Comprehensive characterization techniques and density functional theory (DFT) calculation results unveiled that crystallinity played a dominant role in light absorption and charge dynamics, while surface area primarily influenced mass transfer in photocatalysis. Importantly, our findings revealed that crystallinity engineering of photocatalyst achieved a greater impact on photocatalytic hydrogen evolution than that from mass transfer enhancement. Consequently, CN-HC demonstrated a remarkable improvement in photocatalytic performance for hydrogen evolution (6465.4 μmol h−1 g−1), surpassing both C 3 N 4 and CN-HA by 19.4- and 2.4-fold, respectively, accompanied by a high apparent quantum yield of 23.8 % at 420 nm. This study not only unveils the dominant factor influencing the activity of photocatalysts but also provides a modified approach for robust solar fuel production, shedding light on the path toward efficient and sustainable energy conversion. [ABSTRACT FROM AUTHOR]

Although silicon carbide (SiC) metal oxide semiconductor field-effect transistors (MOSFETs) are commercially available, bias temperature instability (BTI) defined as shifts in Vth in SiC MOSFET and Vfb in MOS capacitor after the device is operated at a high temperature, seriously affects device reliability and limits further commercial applications. These instabilities are mainly attributed to charge trapping at and near the SiC/SiO2 interface and mobile ions in a gate oxide. The consequences of Vth instability are serious and can worsen the performance and lifetime of SiC MOS devices. In this review, the SiC/SiO2 interface issue is introduced, and BTI occurring in current SiC MOS devices is described in detail. Vth/Vfb instability behavior induced by measurement and stress conditions, microscopic defects and instability mechanisms, recent measurement techniques of near-interfacial oxide traps, and BTI improvement resulting from the fabrication processes are described. BTI improvement mainly involves the control of charge trapping and movements of ions. The fabrication processes are related to oxidation and pre- and post-oxidation treatments. This review can help deepen our understanding of BTI and reduce its influence on SiC MOS devices performance. [ABSTRACT FROM AUTHOR]

By the aid of transient photovoltage, photo-generated carrier transfer mechanism of SnS 2 /g-C 3 N 4 composite has been suggested by interfacial electric field direction. Constructing heterojunction is an effective way to improve the photo-generated carrier separation efficiency and photocatalytic activity. Here, we construct SnS 2 /g-C 3 N 4 heterojunctions by in-situ growth of SnS 2 on the g-C 3 N 4. By adjusting annealing temperatures, the SnS 2 /g-C 3 N 4 -180 and SnS 2 /g-C 3 N 4 -120 samples could meet Z-scheme carrier transfer mechanism and conventional type-II charge transfer mechanism, respectively. By the aid of surface photovoltage spectra, the photo-generated carrier transfer direction and the driving force of the charge transfer are suggested. This difference in these two charge transfer mechanisms is supposed to be mainly related to the discrepancy in work functions of the SnS 2 treated at different temperatures. This work provides an effective method to understand the Z-scheme carrier transfer mechanism, which could help us to design Z-scheme photocatalysts for higher hydrogen evolution activity. [ABSTRACT FROM AUTHOR]

The loading of PDS improves the separation of photogenerated carriers, suppresses the bulk and surface recombination (including surface recombination of the back electron(BER)), and enhances the water oxidation kinetics, synthetically improves the PEC water oxidation performance [Display omitted] The kinetic competition between water oxidation/electron extraction processes and recombination behaviors is a key consideration in the development of efficient photoanodes for solar-driven water splitting. Investigating the photogenerated charge behaviors could guide the construction of high-efficiency photoanodes. In this study, the charge carrier kinetics involved in photoelectrochemical water oxidation of PDS/Ti-Fe 2 O 3 were analyzed using surface photovoltage (SPV), transient photovoltage (TPV), short-pulse transient photocurrent (TPC) and photoelectrochemical impedance spectra (PEIS). The TPC results indicate the interfacial electric field introduced by the PDS loading increases the electron extraction and suppresses the bulk recombination, enhancing the spatial separation of photogenerated charges, which is consistent with the SPV and TPV results. Besides, the surface recombination of the back electron (BER) is also attenuated, which enhances the long-lived holes at the surface of PDS/Ti-Fe 2 O 3 photoanode. Similarly, as obtained by PEIS fitting, the loading of PDS accelerates holes transfer at the photoanode/electrolyte interface, and increases the utilization of long-lived holes. In other word, the recombination behaviors of photogenerated charges are restrained both in the bulk and surface of the photoanode after the deposition of PDS, leading to enhanced PEC performance. These findings highlight the importance of understanding charge carrier dynamics in the design of high-efficient photoanodes. [ABSTRACT FROM AUTHOR]

An effective scheme and technical means for understanding the mechanism of interfacial charge transfer. [Display omitted] • The Z-scheme Ti-ZFO/In 2 O 3 photoelectrode was successfully constructed. • Ti-ZFO/In 2 O 3 reaches 2.2 mA/cm2 at 1.23 V vs. RHE, which is 7 times that of pure Ti-ZFO. • The Z-scheme Ti-ZFO/In 2 O 3 could promote the separation and transfer of charges effectively. • This work provides an effective method and technical means to understanding the Z-scheme mechanism. Ti-ZnFe 2 O 4 photoanode has attracted extensive attention in photoelectrochemical (PEC) water oxidation due to its narrow band gap and good photostability. However, its low efficiency limits its development. Herein, we designed and constructed direct Z-scheme Ti-ZnFe 2 O 4 /In 2 O 3 (Ti-ZFO/In 2 O 3) photoanode. Under the interface electric field, photogenerated holes with stronger oxidation capacity on In 2 O 3 are retained to participate in the water oxidation reaction, and the photocurrent density of Ti-ZFO/In 2 O 3 is much higher than that of pure Ti-ZFO, reaching 2.2 mA/cm2 at 1.23 V vs. RHE. Kelvin Probe, steady-state photovoltage spectroscopy (SPV), transient photovoltage spectroscopy (TPV) and in-situ double beam strategy were used to demonstrate the Z-scheme charge transfer mechanism of Ti-ZFO/In 2 O 3 photoanode. Our work provides an effective scheme and technical means for further understanding the mechanism of interfacial charge transfer. [ABSTRACT FROM AUTHOR]

Abstract In this work, we present a new design for the development of quantum dot sensitized solar cells with a CuSe/Cu x S substrate on F-doped tin oxide as the counter electrode. The best performing CuSe/Cu 0.78 S counter electrode notably achieves a photoelectric conversion efficiency of 5.70% with a significant improvement in the J SC for the CdS/CdSe co-sensitized solar cells, superior to a cell with CuSe (4.80%) or Cu 0.78 S (4.11%) as the counter electrodes. Two types of reverse barriers, including a positive reverse barrier and negative reverse barrier, at the interface between the Cu x S and CuSe are investigated using solid-state measurements from a dark current–voltage test. The transient photovoltage responses and Kelvin probe measurements further demonstrate reduction of the positive reverse barrier between the CuSe and Cu x S interface with increasing Cu/S ratios of Cu x S (x = 0.52–0.78), which is beneficial to the electron transfer from Cu x S to CuSe. The electrochemical catalytic activity and stability of the CuSe/Cu x S counter electrodes are verified with electrochemical impedance spectroscopy, tafel polarization and cyclic voltammetry results, which suggest that CuSe/Cu x S counter electrodes have promising applications in solar cells. Graphical abstract Image 1 Highlights • CuSe/Cu x S CEs are fabricated by screen printing CuSe on Cu x S CE. • The QDSCs based on the CuSe/Cu 0.78 S CE achieves the PCE of 5.70%. • The energy band structures of heterojunction is optimized in composite CE. • The interfacial electron transport process is affected by reverse barriers. • The CuSe/Cu x S CEs show excellent stability in polysulfide electrolyte. [ABSTRACT FROM AUTHOR]

The slow kinetics of water oxidation has become a challenge for photoelectrochemical hydrogen production. Here, a novel organic-inorganic integrated photoanode system was constructed by using MIL-53(Fe) formed during the in-situ etching process as a cocatalyst to modify Ti–Fe 2 O 3. The photocurrent density of Ti–Fe 2 O 3 /MIL-53(Fe) reaches 2.5 mA/cm2, 10 times that of bare Ti–Fe 2 O 3 at 1.23 V vs. RHE, and the water oxidation photocurrent onset potential shifts 105 mV negatively. Ti–Fe 2 O 3 /MIL-53(Fe) reaches 52% at 390 nm for IPCE. The excellent photoelectrochemical performance is due to iron oxide clusters boost charge separation and transfer, in-situ etching exposes more reactive sites, and the tight connection reduces interfacial resistance, which greatly accelerates the surface kinetics of Ti–Fe 2 O 3. The in-depth understanding is provided for in-situ modification of photoanodes by metal organic frameworks in this work. The in-depth understanding is provided for in-situ modification of photoanodes by metal organic frameworks in this work. [Display omitted] • Ti–Fe 2 O 3 /MIL-53(Fe) photoelectrode was successfully constructed. • Ti–Fe 2 O 3 /MIL-53(Fe) reaches 2.5 mA/cm2 at 1.23 V vs. RHE, which is 10 times that of bare Ti–Fe 2 O 3. • MIL-53(Fe) greatly improves the water oxidation reaction kinetics of Ti–Fe 2 O 3. • This work provides a new insight into charge transfer in inorganic-organic hybrid systems. [ABSTRACT FROM AUTHOR]

Linear active disturbance rejection control (LADRC) has been widely used to improve the tracking accuracy and anti-disturbance performance of telescope servo control under disturbances. However, the linear extended state observer (LESO) is sensitive to noise, and its bandwidth is limited by the resonant frequency of the telescope. To enhance the LARDC's ability to attenuate disturbances, a novel cascade anti-disturbance structure (NCADS) with LADRC on the outer speed loop and a nonlinear disturbance observer (NDOB) on the inner current loop is proposed. The NDOB compensates for the dominant disturbance through feedforwarding the q-axis current reference, and the LESO compensates for the residual disturbance on the outer speed loop. First, the NCADS is introduced in a three-closed-loop control framework of PMSM. Then, the design method of the controller for each loop and the NDOB are presented, the parameter-tuning method based on bandwidth is demonstrated, and the convergence of the NDOB is proved. Furthermore, to improve the searching and tracking efficiency of wide-field survey telescopes, the nonlinear tracking differentiator (NTD) was modified to plan the transition process of the position loop, which only needs to set the maximum speed and acceleration of the telescope. Finally, simulations and experiments were performed on a 2.5-m-wide field survey telescope. The experimental results verify that the proposed NCADS method has a better anti-disturbance performance and higher tracking precision than the conventional method, and the improved NTD method does not need to tune parameters and achieved a fast and smooth transition process of the position loop. [ABSTRACT FROM AUTHOR]

Background. Immunotherapy for cervical cancer with type I interferon (IFN) is limited because of the cytotoxicity that accompanies the high doses that are administered. In this study, we investigated the utilization of amniotic fluid-derived mesenchymal stem cells (AF-MSCs) as a means for delivering IFNα to local tumor sites for the suppression of cervical cancer in a mouse model using HeLa cell xenografts. Methods. The tumor tropism ability of AF-MSCs and AF-MSCs genetically modified to overexpress IFNα (IFNα-AF-MSCs) was examined through Transwell in vitro and through fluorescent images and immunohistochemistry in a mouse model. Tumor size and tumor apoptosis were observed to evaluate the efficacy of the targeting therapy. Mechanistically, tumor cell apoptosis was detected by cytometry and TUNEL, and oncogenic proteins c-Myc, p53, and Bcl-2 as well as microvessel density were detected by immunohistochemistry. Results. In this model, intravenously injected AF-MSCs selectively migrated to the tumor sites, participated in tumor construction, and promoted tumor growth. After being genetically modified to overexpress IFNα, the IFNα-AF-MSCs maintained their tumor tropism but could significantly suppress tumor growth. The restrictive efficacy of IFNα-AF-MSCs was associated with the suppression of angiogenesis, inhibition of tumor cell proliferation, and induction of apoptosis in tumor cells. Neither AF-MSCs nor IFNα-AF-MSCs trigger tumor formation. Conclusions. IFNα-AF-MSC-based therapy is feasible and shows potential for treating cervical cancer, suggesting that AF-MSCs may be promising vehicles for delivering targeted anticancer therapy. [ABSTRACT FROM AUTHOR]

Summary: The clustered regularly interspaced short palindromic repeats‐associated protein 9 (CRISPR/Cas9) system is a powerful tool for editing plant genomes. Efficient genome editing of grape (Vitis vinifera) suspension cells using the type II CRISPR/Cas9 system has been demonstrated; however, it has not been established whether this system can be applied to get biallelic mutations in the first generation of grape. In this current study, we designed four guide RNAs for the VvWRKY52 transcription factor gene for using with the CRISPR/Cas9 system, and obtained transgenic plants via Agrobacterium‐mediated transformation, using somatic embryos of the Thompson Seedless cultivar. Analysis of the first‐generation transgenic plants verified 22 mutant plants of the 72 T‐DNA‐inserted plants. Of these, 15 lines carried biallelic mutations and seven were heterozygous. A range of RNA‐guided editing events, including large deletions, were found in the mutant plants, while smaller deletions comprised the majority of the detected mutations. Sequencing of potential off‐target sites for all four targets revealed no off‐target events. In addition, knockout of VvWRKY52 in grape increased the resistance to Botrytis cinerea. We conclude that the CRISPR/Cas9 system allows precise genome editing in the first generation of grape and represents a useful tool for gene functional analysis and grape molecular breeding. [ABSTRACT FROM AUTHOR]

• Hydrothermal, electrodepositon and subsequent KOH treatment methods were used to obtain E–Ti–Fe 2 O 3 photoanode. • The photocurrent density of E–Ti–Fe 2 O 3 reached 3.1 mA/cm2 at 1.23 V vs. RHE. • The dual-suppression of bulk and surface charges recombination occurs on the E–Ti–Fe 2 O 3 photoanode. • The photocurrent density of E–Ti–Fe 2 O 3 was further improved by the modification of CoPi (4.1 mA/cm2 at 1.23 V vs. RHE). Surface treatments are considered as one of the most effective strategies to overcome charges recombination of photoanodes. Herein, the E–Ti–Fe 2 O 3 photoanode was prepared by hydrothermal, electrodepositon and subsequent KOH treatment methods on the surface of Ti–Fe 2 O 3 photoanode. The photocurrent density of E–Ti–Fe 2 O 3 reached 3.1 mA/cm2 at 1.23 V versus reversible hydrogen electrode (vs. RHE), which was about 6.5 times than that of Ti–Fe 2 O 3 (0.48 mA/cm2 at 1.23 V vs. RHE). The photocurrent density of E–Ti–Fe 2 O 3 was further improved by the modification of CoPi (4.1 mA/cm2 at 1.23 V vs. RHE). The excellent PEC activity can be attributed to the dual-suppression of bulk and surface charges recombination, which was proved by work function (WF) measurements, transient photovoltage (TPV) measurements and photoelectrochemistry (PEC) tests. This research provided a deep insight into the bulk and surface charge recombination of the photogenerated charges for photoanode. The bulk and surface recombination of photogenerated charge was inhibited for the optimized E–Ti–Fe 2 O 3 photoanode, particularly, the loading of CoPi further improve the surface water oxidation kinetics. [Display omitted] [ABSTRACT FROM AUTHOR]

Y-doping can effectively improve the performance of HfO x -based resistive random-access memory (RRAM) devices, but the underlying physical mechanism of Y-doping affecting the performance of HfO x -based memristors is still missing and unclear. Although impedance spectroscopy (IS) has been widely used to investigate impedance characteristics and switching mechanisms of RRAM devices, there is less IS analysis on Y-doped HfO x -based RRAM devices as well as devices at different temperatures. Here, the effect of Y-doping on the switching mechanism of HfO x -based RRAM devices with a Ti/HfO x /Pt structure were reported using current–voltage characteristics and IS. The results indicated that doping Y into HfO x films could decrease the forming/operate voltage and improve the RS uniform. Both doped and undoped HfO x -based RRAM devices obeyed the oxygen vacancies (V O) conductive filament model along the grain boundary (GB). Additionally, the GB resistive activation energy of the Y-doped device was inferior to that of the undoped device. It exhibited a shift of the V O trap level towards the conduction band bottom after Y-doping in the HfO x film, which was the main reason for the improved RS performance. [ABSTRACT FROM AUTHOR]

In the two-step preparation of perovskite solar cells, the ambient temperature is the main factor affecting the performance of the cells and controlling the crystallization of perovskite films. In this paper, we demonstrate the importance of resting temperature in the preparation of perovskite solar cells based on the morphology of PbI2 film and perovskite film. The ambient temperature around the PbI2 film directly influences its morphology after resting, and then affects the morphology of the annealed perovskite film. The experimental results show that the optimum ambient temperature for resting PbI2 is 28 °C at which solar cell conversion efficiency is improved to 22.2%. This study is of great significance to the preparation of high-performance PVSCs. [ABSTRACT FROM AUTHOR]

Objective. From the perspective of metabolomics, this study compares the metabolomics characteristics of feces and urine between children with spleen-deficiency and healthy children to explain the scientific connotation of children with spleen-deficiency susceptibility to digestive system diseases from the metabolic level and provide a scientific basis for further research. Methods. This study included 20 children with spleen-deficiencies and 17 healthy children. Children's symptom scores, height, and weight were recorded in groups, and feces and urine samples were collected. The samples were detected using ultrahigh-performance liquid chromatography-mass spectrometry. The data were analyzed using multivariate statistical analysis such as principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA). Related differential metabolites were identified through database comparisons between two groups based on the MS and KEGG. Results. Compared to healthy children, the metabolites glucuronic acid, xanthine, and indole-3-acetaldehyde tend to be reduced in children with spleen-deficiency. Moreover, these children showed an increase in metabolites such as quinic acid, adenine, 4-methyl-5-thiazole-ethanol, 3-formyl indole, and 5-hydroxy indole-3-acetic acid. The condition affected many of the critical metabolic pathways, including the metabolism of tryptophan, cysteine, methionine, and pentose phosphate. Conclusion. The children with spleen-deficiency had disorders at the metabolic level, which might be due to factors such as diet, personal preferences, and genes, leading to various symptoms, making spleen-deficiency children more prone to suffer from digestive diseases than healthy children. The results set a basis for the research on children's TCM constitution, which can be a reference to further studies to deal with the spleen-deficiency. [ABSTRACT FROM AUTHOR]

The photoexcited electrons transfer dynamics at the TiO 2 film/fluorine doped tin oxide (FTO) interface of anatase TiO 2 nanowire arrays (NWAs) and QD-sensitized TiO 2 NWAs films have been studied by using surface photovoltage (SPV) and transient photovoltage (TPV) techniques. Various SPV and TPV responses were obtained when the laser beam was incident from the front side illumination and back side illumination. Based on the work function values of anatase TiO 2 NWAs and FTO, the results indicate that diffusion is the major way for the separation and transfer of the photoexcited charge in the both anatase TiO 2 NWAs and QD-sensitized TiO 2 NWAs films under front side illumination. And the photoexcited charge were separated by drift under the built-in electric field at the TiO 2 film/FTO interface for anatase TiO 2 NWAs and QD-sensitized TiO 2 NWAs films under back side illumination. In addition, under back side illumination the built-in electric field and band structure of CdS/CdSe QDs and anatase TiO 2 NWAs lead to the separation and transfer of the photoexcited charge for CdS/CdSe QDs sensitized TiO 2 NWAs/FTO film. As the intensity of illumination increases, the effect of built-in electric field on the separation and transfer of the photoexcited charge in the QD-sensitized TiO 2 NWAs film decreases. [ABSTRACT FROM AUTHOR]

Human endometrial tissue has become an attractive source of mesenchymal stem cells (MSCs) for cell-based therapies because these MSCs can be easily harvested and have tumour tropism as well as reduced immunogenic and inflammatory properties. Our study aimed to obtain and characterise human endometrial mesenchymal stem cells (EMSCs) and assess their endometriosis tropism. EMSCs were successfully isolated from the endometrium of women undergoing laparoscopy for idiopathic infertility. The EMSCs presented a fibroblast-like morphology during culture. Flow cytometry analyses showed that the cells were positive for the specific stem cell markers CD73, CD90, CD105, CD166, and HLA-ABC (major histocompatibility complex class I (MHC I)) but negative for CD14, CD34, CD45, and HLA-DR (MHC II). Reverse transcription polymerase chain reaction results showed that the EMSCs expressed the stem cell marker OCT4. The EMSCs could differentiate into osteocytes, adipocytes, and chondrocytes under certain conditions. The EMSCs had a high tropism to endometriosis without tumourigenicity. This study enhances the possibility of using EMSCs as drug carriers in human cell-based therapies. Meanwhile, future research could also focus on developing targeted therapies for endometriosis. [ABSTRACT FROM AUTHOR]