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Negative immunoregulatory signal (PD-L1, CXCR4, et al.) and weak immunogenicity elicited immune system failing to detect and destroy cancerous cells. CXCR4 blockade promoted T cell tumor infiltration and increased tumor sensitivity to anti-PD-L1 therapy. Here, pH-responsive reassembled nanomaterials were constructed with anti-PD-L1 peptide and CXCR4 antagonists grafting (APAB), synergized with photothermal therapy for melanoma and breast tumor interference. The self-assembled APAB nanoparticles accumulated in the tumor and rapidly transformed into nanofibers in response to the acidic tumor microenvironment, leading to the exposure of grafted therapeutic agents. APAB enabling to reassemble around tumor cells and remained stable for over 96 h due to the aggregation induced retention (AIR) effect, led to long-term efficiently combined PD-L1 and CXCR4 blockade. Photothermal efficiency (ICG) induced immunogenic cell death (ICD) of tumor cells so as to effectively improve the immunogenicity. The combined therapy (ICG@APAB) could effectively inhibit the growth of primary tumor (∼83.52%) and distant tumor (∼76.24%) in melanoma-bearing mice, and significantly (p < 0.05) prolong the survival time over 42 days. The inhibition assay on tumor metastasis in 4 T1 model mice exhibited ICG@APAB almostly suppressed the occurrence of lung metastases and the expression levels of CD31, MMP-9 and VEGF in tumor decreased by 82.26%, 90.45% and 41.54%, respectively. The in vivo reassembly strategy will offer novel perspectives benefical future immunotherapies and push development of combined therapeutics into clinical settings. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Liver cancer resection is an effective but complex way to treat liver cancer, and complex anatomy is one of the reasons for the difficulty of surgery. The use of 3D technology can help surgeons cope with this dilemma. This article intends to conduct a bibliometric analysis of the role of 3D technology in liver cancer resection. Methods: (TS = (3D) OR TS = (three-dimensional)) AND (TS = (((hepatic) OR (liver)) AND ((cancer) OR (tumor) OR (neoplasm)))) AND (TS = (excision) OR TS = (resection)) was used as a search strategy for data collection in the Web of Science (WoS) Core Collection. CiteSpace, Carrot2 and Microsoft Office Excel were used for data analysis. Results: Three hundred and eighty-eight relevant articles were obtained. Their annual and journal distribution maps were produced. Countries/regions and institutions collaboration, author collaboration, references co-citations and their clusters and keywords co-occurrences and their clusters were constructed. Carrot2 cluster analysis was performed. Conclusions: There was an overall upward trend in the number of publications. China's contribution was greater, and the USA had greater influence. Southern Med Univ was the most influential institution. However, the cooperation between institutions still needs to be further strengthened. Surgical Endoscopy and Other Interventional Techniques was the most published journal. Couinaud C and Soyer P were the authors with the highest citations and centrality, respectively. "Liver planning software accurately predicts postoperative liver volume and measures early regeneration" was the most influential article. 3D printing, 3D CT and 3D reconstruction may be the mainstream of current research, and augmented reality (AR) may be a future hot spot. [ABSTRACT FROM AUTHOR]

InGaN-based light-emitting diodes (LEDs) have higher luminescence efficiency than other materials used for the blue and green LEDs in spite of their relatively high dislocation density. Localization theory has been used to explain this phenomenon, but the direct observation of localization states in the InGaN active region has been rarely reported. In this paper, we propose an LED structure to obtain higher luminescence efficiency in the yellow-green LEDs and directly observe the transition of carriers between different localization states. The localization states were investigated and confirmed by temperature-dependent photoluminescence and excitation power-dependent photoluminescence. The value of the external quantum efficiency also exhibited a higher radiative efficiency of the quantum well with a higher degree of localization states. These results offer a promising means of realizing high-luminescence LEDs. [ABSTRACT FROM AUTHOR]

The Cu‐mediated N−H trifluoroethylation of NH‐containing heteroaromatic compounds with the CF3CHCl2 (HCFC‐123), commercially available in industrial scale, has been achieved. This method can be applied to various NH‐containing heteroaromatic compounds including indoles, pyrroles, pyrazoles and carbazoles. Furthermore, this protocol allows the late‐stage trifluoroethylation of NH‐containing heteroaromatic bioactive‐molecules. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver. Although the RNA modification N6-methyladenine (m6A) has been reported to be involved in HCC carcinogenesis, early diagnostic markers and promising personalized therapeutic targets are still lacking. In this study, we identified that 19 m6A regulators and 34 co-expressed lncRNAs were significantly upregulated in HCC samples; based on these factors, we established a prognostic signal of HCC associated with 9 lncRNAs and 19 m6A regulators using LASSO Cox regression analysis. Kaplan-Meier survival estimate revealed correlations between the risk scores and patients' OS in the training and validation dataset. The ROC curve demonstrated that the risk score-based curve has satisfactory prediction efficiency for both training and validation datasets. Multivariate Cox's proportional hazard regression analysis indicated that the risk score was an independent risk factor within the training and validation dataset. In addition, the risk score could distinguish HCC patients from normal non-cancerous samples and HCC samples of different pathological grades. Eventually, 232 mRNAs were co-expressed with these 9 lncRNAs according to GSE101685 and GSE112790; these mRNAs were enriched in cell cycle and cell metabolic activities, drug metabolism, liver disease-related pathways, and some important cancer related pathways such as p53, MAPK, Wnt, RAS and so forth. The expression of the 9 lncRNAs was significantly higher in HCC samples than that in the neighboring non-cancerous samples. Altogether, by using the Consensus Clustering, PCA, ESTIMATE algorithm, LASSO regression model, Kaplan-Meier survival assessment, ROC curve analysis, and multivariate Cox's proportional hazard regression model analysis, we established a prognostic marker consisting of 9 m6A regulator-related lncRNAs that markers may have prognostic and diagnostic potential for HCC. [ABSTRACT FROM AUTHOR]

Background: The role of multifidus in the biomechanics of lumbar spine remained unclear. Purpose: This study aimed to investigate the role of multifidus in the modeling of lumbar spine and the influence of asymmetric multifidus atrophy on the biomechanics of lumbar spine. Methods: This study considered five different multifidus conditions in the trunk musculoskeletal models: group 1 (with entire multifidus), group 2 (without multifidus), group 3 (multifidus with half of maximum isometric force), group 4 (asymmetric multifidus atrophy on L5/S1 level), and group 5 (asymmetric multifidus atrophy on L4/L5 level). In order to test how different multifidus situations would affect the lumbar spine, four trunk flexional angles (0°, 30°, 60°, and 90°) were simulated. The calculation of muscle activation and muscle force was done using static optimization function in OpenSim. Then, joint reaction forces of L5/S1 and L4/L5 levels were calculated and compared among the groups. Results: The models without multifidus had the highest normalized compressive forces on the L4/L5 level in trunk flexion tasks. In extreme cases produced by group 2 models, the normalized compressive forces on L4/L5 level were 444% (30° flexion), 568% (60° flexion), and 576% (90° flexion) of upper body weight, which were 1.82 times, 1.63 times, and 1.13 times as large as the values computed by the corresponding models in group 1. In 90° flexion, the success rate of simulation in group 2 was 49.6%, followed by group 3 (84.4%), group 4 (89.6%), group 5 (92.8%), and group 1 (92.8%). Conclusions: The results demonstrate that incorporating multifidus in the musculoskeletal model is important for increasing the success rate of simulation and decreasing the incidence of overestimation of compressive load on the lumbar spine. Asymmetric multifidus atrophy has negligible effect on the lower lumbar spine in the trunk flexion posture. The results highlighted the fine-tuning ability of multifidus in equilibrating the loads on the lower back and the necessity of incorporating multifidus in trunk musculoskeletal modeling. [ABSTRACT FROM AUTHOR]

As a public health emergency, the COVID‐19 pandemic has attracted widespread attention from scholars worldwide. Combining social network models, GIS analysis and spatial econometric models, we explored the characteristics of the Wuhan population outflow network and factors affecting the number of COVID‐19 cases. The results show that the Wuhan population outflow network has strong temporal and spatial heterogeneity. Cities in Hubei Province, central cities such as Beijing and Shanghai, and cities rich in tourism resources were the main destinations of Wuhan's population inflow. The distribution of COVID‐19 cases not only showed a strong spatial autocorrelation but also a hierarchical diffusion effect. The benchmark regression results showed that the population outflow from Wuhan determines the number of COVID‐19 cases in other cities. Temperature was negatively correlated with the number of COVID‐19 cases, while the PM2.5 concentration failed the significance test. Thus, the lower is the temperature, the greater are the survival and spread of the virus facilitated. Furthermore, cities with a higher population density and more employees in the middle reaches of the Yangtze River are more vulnerable to COVID‐19. Finally, by replacing the weight matrix and setting instrumental variables, we proved the robustness of the above main conclusions. [ABSTRACT FROM AUTHOR]

Introduction: Interstitial nephritis related to novel oral anticoagulants was only reported in sporadic case reports and none was accompanied by anticoagulants related nephropathy (ARN). Case Report: We presented here a case of biopsy-proven subacute interstitial nephritis (SubAIN) accompanied by ARN after oral dabigatran to alarm clinicians. This case manifested with gross hematuria, acute kidney injury, slightly prolonged thrombin time, moderate anemia, moderate proteinuria, a large quantity of intratubular hemoglobin casts confirmed by hemoglobin antibody immunohistochemical staining which presumed to occur around 1 week after dabigatran and subacute interstitial nephritis accompanied by focal proliferative glomerulonephritis. Serum creatinine level did not continue to elevate after discontinuation of the oral anticoagulant. With the subsequent supportive therapy, it decreased to some extent then reduced to normal with the help of prednisone (half of the full dose). Conclusions: When we came across a patient who manifested as hematuria or acute kidney injury with a history of anticoagulants usage, we should think of ARN and pay more attention on history collection. Secondly, subacute interstitial nephritis may coexist with ARN. Thirdly, hemoglobin immunohistochemical staining may be helpful to make it clear whether the intra-tubular protein casts came from red blood cells. In addition, for those patients who may have decreased kidney function, anticoagulants dose should be reduced to prevent the occurrence of ARN. [ABSTRACT FROM AUTHOR]

Alongside the development of small-sized fuel cells, in situ hydrogen production technologies are essential to enable a compact, reliable and stable fuel supply. Among these technologies, Al-water reaction has tremendous potential and broad market prospect due to its low price, high gravimetric hydrogen storage density, environmentally benign byproducts and convenient storage and transportation. However, there is a passive oxide film on Al surface, hindering the direct reaction of Al with water, which has captured a surge of interest in enhancing the hydrogen production performance of Al-water reaction. In this review, the research progress in Al-water reaction is summarized. First, the physicochemical processes and related influencing factors of Al-water reaction are presented. Second, the strategies for enhancing Al-water reaction are critically discussed from five points of view: addition of alkalis, addition of catalysts, Al alloys, mechanical ball milling and surface modification. After that, the feasibility of hydrogen production from Al scraps is evaluated, and the potential applications of Al-water reaction are mapped. Finally, the challenges and opportunities of Al-hydrogen technology for fuel cell applications are outlined. [Display omitted] • Mechanisms and related influencing factors of Al-water reaction were presented. • The strategies for enhancing Al-water reaction were critically discussed. • The feasibility of hydrogen production from Al scraps was evaluated. • The potential applications of Al-water reaction were mapped. • Challenges and opportunities of Al-hydrogen technology for fuel cells were outlined. [ABSTRACT FROM AUTHOR]

The classical Pummerer rearrangement of 2,2,2‐trifluoroethylaryl sulfoxide with trifluoracetic anhydride (TFAA) affords the S,O‐acetal efficiently. In the presence of trifluoracetic acid (TFA) as the co‐solvent, the S,O‐acetal can regenerate reactive thionium intermediate of Pummerer rearrangement. When employing arenes as nucleophiles, this strategy produces corresponding 1‐thiyl‐2,2,2‐trifluoroethyl arenes with excellent yields under metal‐free conditions. [ABSTRACT FROM AUTHOR]

Fire detection methods based on the Convolutional Neural Networks (CNN) have advantages of high accuracy, wide coverage and robustness, receiving significant attention from researchers. Among CNN‐based methods, ResNet has achieved better performance than other CNN frameworks in fire detection system, since it uses stacked residual blocks to enlarge the receptive field to overcome the vanishing gradient problem with residual learning. The merits of ResNet can be attributed to the similarity between ResNet and the single‐step explicit solver for Ordinary Differential Equations (ODEs), for example, the Euler method. Motivated by the theory of numerical ODE that a multi‐step implicit solver has higher accuracy than a single‐step explicit solver, the Multi‐step Implicit Adams predictor‐corrector (MIAPC) network for fire detection is proposed. The MIAPC method is first mapped to a corresponding predictor‐corrector Adams block which achieves higher accuracy than a single‐step explicit solver. Then, Adaptive Feature Fusion (AFF) and the Spatial Attention Layer (SAL) are utilized to extract hierarchical features from stacked predictor‐corrector Adams blocks, forming the corresponding Adams module. Finally, the 4 Adams modules which are made of 4, 6, 8, 10 predictor‐corrector Adams blocks and followed by AFF and SAL form the crucial ODE‐based approximation part in the proposed network. By adding a simple feature extraction and detection in front of and after the ODE‐based approximation part, the MIAPC network is built. Experiments demonstrate that the method achieves 87% accuracy in the challenging test dataset, outperforming existing methods by at least 6%. Besides, the 5.3M model size with inference speed of 4.7 frames/second in CPU and 65.7 frames/second in GPU enables the proposed method to be used in practical applications. [ABSTRACT FROM AUTHOR]

Plasmonic photodetection based on the hot-electron generation in nanostructures is a promising strategy for sub-band detection due to the high conversion efficiencies; however, it is plagued with the high dark current. In this paper, we have demonstrated the plasmonic photodetection with dark current suppression to create a Si-based broadband photodetector with enhanced performance in the short-wavelength infrared (SWIR) region. By hybridizing a 3 nm Au layer with the spherical Au nanoparticles (NPs) formed by rapid thermal annealing (RTA) on Si substrate, a well-behaved ITO/Au/Au NPs/n-Si Schottky photodetector with suppressed dark current and enhanced absorption in the SWIR region is obtained. This optimized detector shows a broad detection beyond 1200 nm and a high responsivity of 22.82 mA/W at 1310 nm at −1 V, as well as a low dark current density on the order of 10−5 A/cm2. Such a Si-based plasmon-enhanced detector with desirable performance in dark current will be a promising strategy for realization of the high SNR detector while keeping fabrication costs low. [ABSTRACT FROM AUTHOR]

SiGe spheres with different diameters are successfully fabricated on a virtual SiGe template using a laser irradiation method. The results from scanning electron microscopy and micro-Raman spectroscopy reveal that the diameter and Ge composition of the SiGe spheres can be well controlled by adjusting the laser energy density. In addition, the transmission electron microscopy results show that Ge composition inside the SiGe spheres is almost uniform in a well-defined, nearly spherical outline. As a convenient method to prepare sphere-shaped SiGe micro/nanostructures with tunable Ge composition and size, this technique is expected to be useful for SiGe-based material growth and micro/optoelectronic device fabrication. [ABSTRACT FROM AUTHOR]

Nasotracheal intubation (NTI) is an advanced airway management technique, in which a flexible endoscope is inserted into the patient's trachea from the nasal cavity. Due to the hand-eye coordination requirement, the operation of the flexible endoscope in a narrow workspace is a challenge, even for experienced surgeons. In this study, a novel robotic nasotracheal intubation system (RNIS) is proposed to automatically steer the endoscope along the upper respiratory tract. The configuration of the RNIS meets the motion requirement of the flexible endoscope. A lumen center detection method with Kalman filter is designed to determine the position of the lumen center in endoscopic images. Then, a fuzzy logic-based control strategy is developed to enable the RNIS to achieve automatic endoscope steering. Control parameters are updated online using a fuzzy logic algorithm to handle uncertainty. Movements in three degrees of freedom of the endoscope are controlled by the RNIS using visual feedback. Finally, experiments based on a motion simulator and a training mannequin are conducted. Results demonstrate that the proposed RNIS can successfully steer the flexible endoscope along the upper respiratory tract. Automated robotic endoscopes outperform manual operations in terms of operational accuracy. [ABSTRACT FROM AUTHOR]

In addition to rhizobia, other non-symbiotic endophytic bacteria also have been simultaneously isolated from the same root nodules. The existence of non-symbiotic endophytic bacteria in leguminous root nodules is a universal phenomenon. The vast majority of studies have detected endophytic bacteria in other plant tissues. In contrast, little systemic observation has been made on the non-symbiotic endophytic bacteria within leguminous root nodules. The present investigation was carried out to isolate plant growth-promoting endophytic non-symbiotic bacteria from indigenous leguminous Sphaerophysa salsula and their influence on plant growth. A total of 65 endophytic root nodule-associated bacteria were isolated from indigenous legume S. salsula growing in the northwestern arid regions of China. When combining our previous work with the current study, sequence analysis of the nifH gene revealed that the strain belonging to non-nodulating Bacillus pumilus Qtx-10 had genes similar to those of Rhizobium leguminosarum Qtx-10-1. The results indicated that horizontal gene transfer could have occurred between rhizobia and non-symbiotic endophyties. Under pot culture conditions, out of the 20 representative endophytic isolates, 15 with plant growth-promoting traits, such as IAA production, ACC deaminase, phosphate solubilization, chitinase, siderophore, and fungal inhibition activity showed plant growth-promoting activity with respect to various plant parameters such as chlorophyll content, fresh weight of plant, shoot length, nodule number per plant and average nodule weight per plant when co-inoculated with rhizobial bioinoculant Mesorhizobium sp. Zw-19 under N-free culture conditions. Among them, Bacillus pumilus Qtx-10 and Streptomyces bottropensis Gt-10 were excellent plant growth-promoting bacteria, which enhanced the seeding fresh weight by 87.5% and the shoot length by 89.4%, respectively. The number of nodules grew more than 31.89% under field conditions. Our findings indicate the frequent presence of these non-symbiotic endophytic bacteria within root nodules, and that they help to improve nodulation and nitrogen fixation in legume plants through synergistic interactions with rhizobia. [ABSTRACT FROM AUTHOR]

Breast cancer (BC) is a common malignancy among women and the leading cause of female cancer mortality worldwide. In recent years, increasing evidence has shown that long non-coding RNAs (lncRNAs) can act as competing endogenous RNAs (ceRNAs) in human cancer and that they are involved in many biological processes, including proliferation, migration, apoptosis and invasion. In the present study, the biological function and molecular mechanism of ataxin 8 opposite strand (ATXN8OS) in BC tissue and cell lines were investigated. It was found that ATXN8OS was markedly up-regulated in BC tissue and cell lines, and that its level of overexpression was inversely linked with the overall survival rate of patients with BC. Knockdown of ATXN8OS inhibited proliferation, viability and invasion in the human MCF7 and MDA-MB-231 BC cell lines. In addition, microRNA-204 (miR-204) was negatively associated with the expression of ATXN8OS in BC tissues and cell lines. A luciferase assay demonstrated a direct binding site for miR-204 within ATXN8OS, and inhibition of miR-204 stimulated the tumour-promoting effect of ATXN8OS on BC cells. In conclusion, the present study suggested that ATXN8OS acts as a tumour promoter by sequestering miR-204 during the development of BC, therefore providing a mechanistic insight which may facilitate the diagnosis and treatment of BC. [ABSTRACT FROM AUTHOR]

Summary: Determining an appropriate grasp configuration for multi-finger grasping is difficult due to the complexity of robotic hands. The multi-finger grasp planning should consider not only geometry constraints of objects but also kinematics and dynamics of robotic hand. In this paper, a precision grasp-planning framework is presented for multi-finger hand to grasp unknown objects. First, the manipulation capabilities of the robotic hand are analyzed. The analysis results are further used as bases for the precision grasp planning. Second, the superquadric (SQ) fitting method is used for approximating unknown object models. Finally, a local–global optimization method is implemented to find appropriate grasp configurations for dexterous hand. The presented planning framework is validated in simulation experiments. Simulation results demonstrated that the presented grasp-planning framework enables the multi-finger hand to grasp unknown objects effectively. [ABSTRACT FROM AUTHOR]

New variable-order fractional chaotic systems are proposed in this paper. A concept of short memory is introduced where the initial point in the Caputo derivative is varied. The fractional order is defined by the use of a piecewise constant function which leads to rich chaotic dynamics. The predictor–corrector method is adopted, and numerical solutions of fractional delay equations are obtained. Then, this concept is extended to fractional difference equations, and generalized chaotic behaviors are discussed numerically. Finally, the new fractional chaotic models are applied to block image encryption and each block has a different fractional order. The new chaotic system improves security of the image encryption and saves the encryption time greatly. [ABSTRACT FROM AUTHOR]

We propose a new method for fabricating large-scale uniform high-quality submicron inverted pyramid pit arrays by laser interference lithography (LIL), combined with dry etching and wet etching. In this process, uniform photoresist dot arrays are fabricated by LIL for 2-inch wafer. Dry etching is used to ensure the formation of the fluorocarbon organic polymer (FOP) mask layer. Wet etching parameters are investigated in details and inverted pyramid pits with {111} sidewalls are formed by anisotropic wet etching. Using this method, we have successfully produced uniform high-quality inverted pyramid pit arrays with the average size of 240 nm and the period of 450 nm. The size of pits can be tailored between 200 nm and 400 nm and the size deviation of inverted pyramid pits is 6.7% over the whole 2-inch wafer. This method offers a simple, less time consuming and cost-effective process of micro-nano pattern fabrication. Besides, GeSi QDs are quantitatively investigated by a nucleation model which shows GeSi QDs are preferentially grown at the tip of inverted pyramid pit and four intersection lines of two {111} planes inside the pit. • Fabricating submicron inverted pyramid pit arrays by laser interference lithography. • The mask layer of wet etch is fluorocarbon organic polymer caused by dry etch. • The size deviation of prepared patterns is 6.7% over 2-inch wafer. [ABSTRACT FROM AUTHOR]

Abstract Our random bioassay revealed that the CHCl 3 part of Chelonopsis praecox (Lamiaceae) showed significant activity against α -glucosidase with the inhibitory rate of 99.6 ± 0.4 % (330 μg/mL). Bioassay-guided isolation yielded seven new ent -kaurane diterpenoids, chepraecoxins A-G (1 - 7), and three known ones (8 - 10), driven by LC-MS analyses. The structures of chepraecoxins A-G (1 - 7) were elucidated by X-ray crystallographic and extensive spectroscopic analyses. Compounds 1 , 6 , and 10 showed obvious α -glucosidase inhibitory effects with IC 50 values of 305.0, 361.0 and 174.5 μM, respectively. Enzyme kinetics study suggested that compound 1 inhibited the α -glucosidase by a noncompetitive type mechanism (K i = 354.4 μM). Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Abstract The ability to implement semantic Reach-to-grasp (RTG) tasks successfully is a crucial skill for robots. Given unknown objects in an unstructured environment, finding an feasible grasp configuration and generating a constraint-satisfied trajectory to reach it are challenging. In this paper, a learning framework which combines semantic grasp planning with trajectory generation is presented to implement semantic RTG tasks. Firstly, the object of interest is detected by using an object detection model trained by deep learning. A Bayesian-based search algorithm is proposed to find the grasp configuration with highest probability of success from the segmented image of the object using a trained quality network. Secondly, for robotic reaching movements, a model-based trajectory generation method inspired by the human internal model theory is designed to generate a constraint-satisfied trajectory. Finally, the presented framework is validated both in comparative analysis and on real-world experiments. Experimental results demonstrated that the proposed learning framework enables the robots to implement semantic RTG tasks in unstructured environments. Highlights • We proposed a learning framework for the implementation of semantic RTG tasks. • A Bayesian-based search algorithm is designed for grasp planning. • A model-based trajectory generation method is designed to generate reaching movement. [ABSTRACT FROM AUTHOR]

Presents a study which investigated the effects of image potential due to dielectric mismatch on electronic and shallow donor impurity states in GaAs-Ga[sub1-x]Al[subx]As quantum-well wires. Effects of image potential on electronic states; Calculation of the effects of image potential on shallow donor impurity binding energies; Mathematical expression of the motion of an electron in the quantum wire structure.

Plasma protein binding affinity of a drug compound has a strong influence on its pharmacodynamic behavior because it can affect the drug uptake and distribution. In this study, we collected a sizeable dataset consisting of 1830 drug compounds from several accessible sources. A descriptor pool composed of four different types of descriptors (2-D, 3-D, Estate and MACCS) was firstly built and non-dominated sorting genetic algorithm (NSGA-II) combining partial least square (PLS) regression was applied to select important descriptors for model building. Finally, we obtained a consensus model (for five-fold cross-validation: Q 2 = 0.750; RMSE = 16.151) based on five different predictive models built using random forest (RF), support vector machine (SVM), Cubist, Gaussian process (GP), and Boosting. Further, a test set and two external validation datasets were applied to validate its robustness and practicality. For the test set, R T 2 = 0.787 and RMSE T = 14.154; when two external datasets were applied, R Ex 2 = 0.704 and 0.703, RMSE Ex = 18.194 and 17.233 respectively. Additionally, according to OECD principles, y-randomization, Williams plot and scaffold analyses were proposed to validate the reliability and practical application domain of our predictive model. Overall, our consensus model shows a good prediction performance and generalization ability in predicting plasma protein binding (PPB). After analyzing those important descriptors selected by NSGA-II and RF, we concluded that the PPB of a drug compound is mainly related to its lipophilicity, aromatic rings, and partial charge properties. In summary, this study developed a robust and practical consensus model for PPB prediction and it could be used to the distribution evaluation and risk assessment in the early stage of drug development. [ABSTRACT FROM AUTHOR]

In QSAR/QSPR modeling, building an accurate partial least squares (PLS) model usually involves descriptor selection, outlier detection, applicability domain assessment, nonlinear relationship, and model stability problems. In the present study, we presented an ensemble PLS (EnPLS) method for solving these modeling tasks under a unified methodology framework. EnPLS aims at developing a consistent algorithmic framework by means of the idea of ensemble learning and statistical distribution. The approach exploits the fact that the distribution of PLS model coefficients provides a mechanism for ranking and interpreting the effects of variables, whereas the distribution of prediction errors provides a mechanism for differentiating the outliers from normal samples and assessing the applicability domain of models. The use of statistics of these distributions, namely, mean/median value and standard deviation, inherently provides a feasible way to effectively describe the information contained by the original samples. Furthermore, ensemble modeling and prediction based on several cross-predictive PLS models could effectively improve the model prediction performance and increase the model stability to a certain extent. The aqueous solubility data are used to demonstrate the ability of our proposed EnPLS method in solving various modeling tasks such as descriptor selection, outlier detection, applicability domain assessment, performance improvement, and model stability. Finally, a freely available R package implementing EnPLS is developed to facilitate the use of chemists and pharmacologists. The R package is freely available at . [ABSTRACT FROM AUTHOR]

Purpose: Traditional Chinese cervical manipulation (TCCM) has been claimed as an effective treatment for diseases of the cervical spine, but its biomechanical effects on the vertebral body and intervertebral discs remain unclear. The aim of this study was to develop and validate a detailed finite element model of cervical spine, which was then used to investigate the biomechanical response of the cervical spine to TCCM.Methods: The model of a C2-T1 cervical spine was constructed based on CT images of a healthy male volunteer and validated against published in vitro studies under different loading conditions. The detailed force-time data of TCCM were measured on the same volunteer through dynamometric diaphragms. The data were applied on the validated finite element model to simulate TCCM.Results: The current model could offer potentials to effectively reflect the behavior of human cervical spine suitable for biomechanics studies of TCCM. Under simulated TCCM condition, the stress distributions in cervical spine and intervertebral discs could not be completely explained through the traditional theory.Conclusion: Spinal manipulation, or TCCM, might play no role in reducing intradiscal pressure for treating cervical spondylosis. It could cause less stress concentration in intervertebral discs while operating spinal manipulation or TCCM when the adjustment points was chosen near the root of spinous process than the top of spinous process. [ABSTRACT FROM AUTHOR]

[Display omitted] • The ore-bearing diorite and gabbro-diorite of the Yundunkala deposit formed at ∼ 401 Ma. • The ore-bearing magmas are hybrid. • The Yundunkala deposit formed at an island arc environment. Ongoing exploration in East Junggar, Northwest China, has led to the discovery of the intrusion-related Yundukala Au–Cu–Co deposit. The alteration and mineralization in the Yundukala deposit are closely related to diorite and gabbro-diorite, whereas the geochemical features of these ore-related plutons are still unclear. In this study, in order to unlock the nature of the ore-forming magmas, zircon U–Pb dating, whole-rock major and trace elemental and Sr–Nd isotope analysis, as well as zircon O–Hf isotope analysis, were conducted. Our results show that diorite and gabbro-diorite were both generated in the Early Devonian, with ages being 401.3 ± 3.8 Ma and 401.6 ± 4.5 Ma, respectively. Geochemically, they are all characterized by LREE-enriched patterns in chondrite-normalized REE diagrams, and evident enrichment of Rb, U and K and depletion of Nb and Ta contents in primitive mantle-normalized patterns, although the degrees of enrichment and depletion are variable. Isotopically, the diorite and gabbro-diorite display relatively high initial 87Sr/86Sr (0.704966–0.707395) and positive ε Nd (t) (1.29–3.84) of whole-rock, as well as positive zircon δ18O (5.3–8.9 ‰) and ε Hf (t) (2.4–18.8). These lines of evidence collectively indicate that these magmatic rocks were generated by mixing between mantle- and crustal-derived melts, and were emplacement in an island arc environment. The magma mixing during the formation of ore-bearing diorite and gabbro-diorite might bring abundant sulfur and metals, thus favoring the formation of Au–Cu–Co mineralization. This work emphasizes that further mineral exploration in East Junggar needs to pay attention to the Early Devonian granitoids. [ABSTRACT FROM AUTHOR]

Convolutional Neural Networks (CNNs) have been used in resource-constrained edge devices, including safety-critical applications. However, recent studies demonstrate that soft errors may result in CNN prediction failures. Many approaches are proposed at the end of layers to detect computation errors. Still, these approaches incur severe overheads or cannot detect errors in memory, e.g., traditional Double Modular Redundancy (DMR) can protect data integrity in memory, but it incurs significant overheads on time and memory. Some existing DNN-specific approaches are lightweight to protect DNNs from transient faults but cannot provide high fault coverage to detect permanent faults in memory. Thus, we propose two low-cost software approaches, channel-based weight checksum and layer-based output checksum, which protect the integrity of weights and layer outputs in memory. We perform a large number of fault injections to evaluate the performance of the proposed approaches and compare them with other approaches. The results show that combining the proposed approaches can provide approximately 100 % fault coverage for weights and layer outputs in memory. The combination increases total time and memory overheads by 4 % and 17 %, respectively, for DNNs that run sequentially. In addition, we observe that the layer-based output checksum can improve the error resilience of register files because most SDCs caused by register file errors are induced by the control flow error and the pointer error. Finally, we present a case study on MobileNet to show that our approaches can be generalized to other DNN libraries that run parallel by dividing the single-layer execution into N parts. When N is 2, our approaches increase total time and memory overheads by 7.4 % and 31 %, respectively. • Rank the error resilience of layers' weights and intermediate data in memory for DNNs. • Propose two lightweight checksum approaches to protect the weights and intermediate data in memory for embedded CNNs. • Observe that a considerable part of critical SDCs caused by register errors are induced by control-flow errors. • Present an insightful comparison on protecting embedded CNNs' memory among the existing DNN-specific, DMR, and our proposed approaches. [ABSTRACT FROM AUTHOR]

Laminectomy is a typical high-risk surgical operation on the spine, during which milling is the key procedure to remove part of vertebral lamina and release the pressure on the spinal nerve. Because many important vessels and nerves surround the vertebral lamina, any incorrect maneuver can cause irreparable damage to patients. In this paper, a fuzzy force control is designed specifically for vertebral lamina milling. The force control is implemented to adjust the milling parameters to copy the complex anatomical structure of the vertebral lamina, and fuzzy combiner is integrated into the force controller to tune its control parameters on-line. For safety purposes, the state detection method based on energy consumption is proposed in the process of vertebral lamina milling. Three different milling states can be detected and the safety control point, which is the stop point of the milling, is found, effectively improving the quality of the vertebral lamina milling. The results of contrast experiments showed that the milling process under fuzzy force control has shorter time and more stable longitudinal contact force. The state detection method based on energy consumption can detect the three milling states, resulting in an acceptable thickness of the remaining vertebral lamina. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the efficacy and safety of topical diclofenac therapy for osteoarthritis (OA). A meta-analysis of randomized controlled trials was conducted. A comprehensive literature search, covering the databases of Medline, the Cochrane Central Register of Controlled Trials, and EMBASE, was conducted in September 2014 to identify the randomized controlled trials which adopted the topical diclofenac therapy for OA. A total of nine papers were included in this meta-analysis. Topical diclofenac appears to be effective in both pain relief (standard mean differences (SMD) = 0.40; 95 % confidence interval (CI) 0.19 to 0.62; P = 0.0003) and function improvement (SMD = 0.23; 95 % CI 0.03 to 0.43; P = 0.03) when compared with the control group. The sensitivity analysis and subgroup analysis showed that the result of pain intensity was stable and reliable, while the result of physical function improvement was vague. With respect to safety, topical diclofenac demonstrated a higher incidence of adverse events such as dry skin, rash, dermatitis, neck pain, and withdrawal. Topical diclofenac is effective in pain relief as a treatment of OA. It may also have a potential effect in function improvement, which needs further studies to be explored. Although, some adverse effects were observed in the application of topical diclofenac, none of them was serious. [ABSTRACT FROM AUTHOR]

A nonequilibrium molecular dynamics (NEMD) method is employed to study the dynamics of two identical vesicles with attractive interactions immersed in shear flow. The dynamics behaviors of attractive vesicles depend on the attractive interactions and the shear rates simultaneously. There are four motion types for attractive vesicles in shear flow: a coupled-tumbling (CTB) motion, a coupled-trembling (CTR) motion, a collision/rotation mixture (CRM) motion and a separated-tank-treading (STT) motion, which are determined by the competition between the shear flow and the attractive interactions. Furthermore, the dynamics behavior of an individual vesicle shows three main motion types such as tumbling, trembling and tank-treading motions, and relies mainly on the shear rates. Meanwhile, comparisons with rigid vesicles for the dynamics behaviors are made, and the collision/rotation mixture (M) motion isn't observed for rigid vesicles. [ABSTRACT FROM AUTHOR]

In this work, a novel hybrid graphene/InGaN-based multiple quantum wells (MQWs) structure has been fabricated. Compared to the sample conventional structure (CS), the utilization of graphene transferred on top GaN layer significantly enhances the internal quantum efficiency and relatively photoluminescence intensity. Furthermore, the excitons in the MQWs of sample hybrid structure (HS) have a shorter decay lifetime of 3.4 ns than that of 6.7 ns for sample CS. These results are probably attributed to the free carriers in the graphene layer, which can screen the piezoelectric field in the active region and thus present a free quantum-confined Stark effect-like behavior. Our work demonstrates that the graphene on the top GaN layer can effectively increase the recombination rate in sample HS, which may further improve LEDs' performance. [ABSTRACT FROM AUTHOR]

Abstract: Nanoporous Cu with tunable pore size (20–50 nm) are synthesized through chemical dealloying of the Mg65Cu25Gd10 metallic glass in sulfuric acid solution. X-ray diffraction (XRD) and scanning electron microscopy (SEM) demonstrated the formation of mixing structures consisting of amorphous matrix and fcc-Cu ligaments with nanoporous structure in the dealloyed samples. The nanoporous alloy obtained shows superior catalytic activity in degrading phenol-containing wastewater, e.g., the degradation rate increases by 2–4 times as compared to the un-dealloyed Mg-based metallic glass. It was also found that surface wettability plays an important role in degradation, which results in a better catalytic performance in the sample with coarser nanoporous structure although it has relatively less specific surface area as compared to the samples with finer pores. Finally, the mechanism for degradation of phenol is discussed. [Copyright &y& Elsevier]

The effect of initial gas pressure on Al–water reaction was investigated systematically. It was found that there is a non-monotonic relationship between the initial pressure and the induction time for the beginning of Al–water reaction. The induction time decreases with decreasing the initial pressure at the first stage from atmospheric pressure, then reaches a minimum, and finally increases with further decreasing the initial pressure. The mechanism analyses revealed that the special vacuum pressure corresponding to the minimum induction time is close to the saturated vapor pressure, below which probably there are some vapor bubbles passing or adsorbing on Al particle surfaces due to boiling, retarding the hydration process of Al surface oxide film and increasing the reaction induction time. The present results imply that a suitable initial gas pressure should be chosen for Al–water reaction to generate hydrogen. [ABSTRACT FROM AUTHOR]

Abstract: The Doppler rate estimation on coherent sinusoidal pulse train, which can be applied in the passive emitter location systems, is investigated in this paper. When the pulse repetition interval (PRI) is constant, a DFT-based Doppler rate estimation algorithm is proposed and its performance is briefly analyzed. In the case of non-constant PRI, a least-squares-fitting based Doppler rate estimator (LSFE) is proposed. The mean square error is computed in closed form and the threshold signal-to-noise ratio (SNR) is analyzed. The Cramer–Rao lower bound on Doppler rate estimation is derived whereafter, and is compared to the mean square error of the LSFE. Monte Carlo simulations show that when operating above the threshold SNR, the proposed approach achieves the CRLB. The threshold SNRs in the simulations are basically coincident with the theoretical values. [Copyright &y& Elsevier]

Short single‐wall carbon nanotubes (SWCNTs)/epoxy composites were fabricated by a procedure of cutting and functionalizing SWCNTs, dispersion and curing, with a very low weight ratio of SWCNTs from 0.03% to 0.5%. It was found that the tensile fracture strength of composites increases with increasing SWCNT content initially, then reaches a maximum at 0.05 wt% and finally decreases with further increasing the SWCNT content. The fracture strength of the composite with 0.05 wt% SWCNTs (78.46 MPa) is ~160% of that of pure epoxy sample (48.64 MPa). A model analysis based on the competition of local matrix fracture and the debonding of short SWCNT was proposed. It revealed that there is a transition from local matrix fracture to the debonding of SWCNT when the SWCNT content increases, this transition leads to the decrease in the tensile strength. Further analyses indicated that the content of carbon nanotubes (CNTs) at the transition depends on their radius and length. Considering the effect of surface cracks on the fracture strength of pure epoxy sample, the theoretical analyses are qualitatively in agreement with the experimental results. The present study partly explains why the fracture strength of CNT reinforced composites has various results for a similar CNT loading in previous works. [ABSTRACT FROM AUTHOR]

Castration-resistant prostate cancer (CRPC) and its treatment are challenging issues in prostate cancer management. Here, we report that miR-663 is upregulated in CRPC tissues. Overexpression of miR-663 in prostate LNCaP cells promotes cell proliferation and invasion, neuroendocrine differentiation, and reduction in dihydrotestosterone-induced upregulation of prostate-specific antigen expression. Furthermore, results of in situ hybridization show that miR-663 expression is correlated with Gleason score and TNM stage and is an independent prognostic predictor of clinical recurrence. Together, these findings suggest that miR-663 is a potential oncomiR for CRPC and may serve as a tumor biomarker for the early diagnosis of CRPC. J. Cell. Physiol. 229: 834-844, 2014. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

A method is suggested to improve the characteristics of light emitting diodes (LEDs) by using p-GaN structure with heavily Mg-doping grown at low temperature in full N2 environment. The LED exhibits a 36.4% enhancement in light output power (LOP) at 222 A cm−2 due to the higher hole concentration as compared to the normal p-GaN layer. Meanwhile, the experimental results prove that the optimized LED structure shows reduced efficiency droop behavior, smaller peak wavelength blueshift and narrower electroluminescence (EL) spectrum broadening. [ABSTRACT FROM AUTHOR]

Abstract: The Al–water reaction has attracted considerable attention in the past few years, because it is an economically viable way to supply hydrogen for portable and kW-grade fuel cells. The water type is found to have a significant impact on Al–water reaction. In this work, the effect of trace species in water on Al–water reaction is investigated systematically. It is found that the trace organic acids originated from the decay of botanies and animals in nature and trace F− ions, rather than other cations and anions, play a key role in the reaction dynamics of Al with water. The mechanism analyses reveal that the organic acids and F− ions form complexes with aluminol groups on Al particle surfaces to impede the hydration process of Al surface oxide film and retard the reaction of Al with water. The present results imply that a suitable water should be chosen for the Al–water reaction to generate hydrogen. At the same time, the organic acids and trace F− ions could be used as the agents to prevent undesirable Al–water reaction. [Copyright &y& Elsevier]

Catharanthus roseus is a well-known traditional herbal medicine for the treatment of cancer, hypertension, scald, and sore in China. Phytochemical investigation on the twigs and leaves of this species led to the isolation of two new monoterpene indole alkaloids, catharanosines A (1) and B (2), and six known analogues (3–8). Structures of 1 and 2 were established by 1H-, 13C- and 2D-NMR, and HREIMS data. The absolute configuration of 1 was confirmed by single-crystal X-ray diffraction analysis. Compound 2 represented an unprecedented aspidosperma-type alkaloid with a 2-piperidinyl moiety at C-10. Compounds 6–8 exhibited remarkable Cav3.1 low voltage-gated calcium channel (LVGCC) inhibitory activity with IC50 values of 11.83 ± 1.02, 14.3 ± 1.20, and 14.54 ± 0.99 μM, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Image stitching is an important technology to produce a panorama or larger image by combining several images with overlapped areas. In many biomedical researches, image stitching is highly desirable to acquire a panoramic image which represents large areas of certain structures or whole sections, while retaining microscopic resolution. In this study, we develop a fast normal light microscope image stitching algorithm based on feature extraction. At first, an algorithm of scale-space reconstruction of speeded-up robust features (SURF) was proposed to extract features from the images to be stitched with a short time and higher repeatability. Then, the histogram equalization (HE) method was employed to preprocess the images to enhance their contrast for extracting more features. Thirdly, the rough overlapping zones of the images preprocessed were calculated by phase correlation, and the improved SURF was used to extract the image features in the rough overlapping areas. Fourthly, the features were corresponded by matching algorithm and the transformation parameters were estimated, then the images were blended seamlessly. Finally, this procedure was applied to stitch normal light microscope images to verify its validity. Our experimental results demonstrate that the improved SURF algorithm is very robust to viewpoint, illumination, blur, rotation and zoom of the images and our method is able to stitch microscope images automatically with high precision and high speed. Also, the method proposed in this paper is applicable to registration and stitching of common images as well as stitching the microscope images in the field of virtual microscope for the purpose of observing, exchanging, saving, and establishing a database of microscope images. [Copyright &y& Elsevier]

Studying rhizobia in the root nodules of Sphaerophysa salsula (Pall.) DC in the northwest of China, we obtained five strains classified as genus Rhizobium on the basis of their 16S rRNA gene sequences. The sequence similarity of strain CCNWQTX14 with the most related species was 99.0%. Further phylogenetic analysis of housekeeping genes ( recA and atpD) suggested the five strains comprised a novel lineage within Rhizobium. The nifH and nodD gene sequences of CCNWQTX14 were phylogenetically closely related with those of Sinorhizobium kummerowiae and R. sphaerophysae, respectively. The five strains isolated from different places were also distinct from related Rhizobium species using ERIC fingerprint profiles. The DNA-DNA hybridization value was 41.8% between CCNWQTX14 and Rhizobium sphaerophysae CCNWGS0238. Our novel strains were only able to form effective nodules on its original host Sphaerophysa salsula. Our data showed that the five Rhizobium strains formed a unique genomic species, for which a novel species Rhizobium helanshanense sp. nov. is proposed. The type strain is CCNWQTX14 (=ACCC 16237 =HAMBI 3083). [ABSTRACT FROM AUTHOR]

A total of 115 endophytic bacteria were isolated from root nodules of the wild legume Sphaerophysa salsula grown in two ecological regions of Loess Plateau in China. The genetic diversity and phylogeny of the strains were revealed by restriction fragment length polymorphism and sequencing of 16S rRNA gene and enterobacterial repetitive intergenic consensus-PCR. Their symbiotic capacity was checked by nodulation tests and analysis of nifH gene sequence. This is the first systematic study on endophytic bacteria associated with S. salsula root nodules. Fifty of the strains found were symbiotic bacteria belonging to eight putative species in the genera Mesorhizobium, Rhizobium and Sinorhizobium, harboring similar nifH genes; Mesorhizobium gobiense was the main group and 65 strains were nonsymbiotic bacteria related to 17 species in the genera Paracoccus, Sphingomonas, Inquilinus, Pseudomonas, Serratia, Mycobacterium, Nocardia, Streptomyces, Paenibacillus, Brevibacillus, Staphylococcus, Lysinibacillus and Bacillus, which were universally coexistent with symbiotic bacteria in the nodules. Differing from other similar studies, the present study is the first time that symbiotic and nonsymbiotic bacteria have been simultaneously isolated from the same root nodules, offering the possibility to accurately reveal the correlation between these two kinds of bacteria. These results provide valuable information about the interactions among the symbiotic bacteria, nonsymbiotic bacteria and their habitats. [ABSTRACT FROM AUTHOR]

Abstract: Three different modification agents, γ-Al2O3, α-Al2O3, and TiO2 were used to modify Al particle surfaces. The effect of different modification agents on hydrogen-generation by the reaction of modified Al powder with water was investigated. It was found that different modification agents have different effect on the reaction dynamics of Al with water. The complete hydrogen-generation time of γ-Al2O3 modified Al powder is obviously shorter than that of α-Al2O3 and TiO2 modified Al powders, because of their different induction time for the beginning of the reaction. Possible mechanism analyses indicated that the phase transformation and resultant weakening of Al particle surface layer during processing strongly depends on the nucleation energy barrier on modification oxide grains. As γ-Al2O3 has a low nucleation energy barrier, the phase transformation of Al particle surface layer is relatively complete so that γ-Al2O3 modified Al powder has a short induction and complete reaction time with water. This implies that the Al surface modification probably originates from the phase change of its surface layer. [ABSTRACT FROM AUTHOR]

Abstract: Dysfunction of the microRNA (miR) network has been emerging as a major regulator in neurological diseases. However, little is known about the functional significance of unique miRs in ischemic brain damage. Here, we found that miR-497 is induced in mouse brain after transient middle cerebral artery occlusion (MCAO) and mouse N2A neuroblastoma (N2A) cells after oxygen-glucose deprivation (OGD). Loss-of-miR-497 function significantly suppresses OGD-induced N2A cell death, whereas gain-of-miR-497 function aggravates OGD-induced neuronal loss. Moreover, miR-497 directly binds to the predicted 3′-UTR target sites of bcl-2/-w genes. Furthermore, knockdown of cerebral miR-497 effectively enhances bcl-2/-w protein levels in the ischemic region, attenuates ischemic brain infarction, and improves neurological outcomes in mice after focal cerebral ischemia. Taken together, our data suggest that miR-497 promotes ischemic neuronal death by negatively regulating antiapoptotic proteins, bcl-2 and bcl-w. We raise the possibility that this pathway may contribute to the pathogenesis of the ischemic brain injury in stroke. [Copyright &y& Elsevier]

TDCJTB, BMDIN and TDIN have been synthesized for using as red fluorescent dye molecules in organic light-emitting diodes (OLEDs). The Commission International d''Eclairage (CIE) coordinates and PL peaks of the devices are [0.61, 0.39], [0.65, 0.35], [0.62, 0.38] and 579nm, 619nm, 597nm, respectively. Compared with traditional DCM ([0.58, 0.41], 575nm) the three devices have better brightness and CIE coordinates. When TBQ is doped in the three materials the EL efficiency can all be improved at different levels. BMDIN as a high efficient red organic light-emitting material based on this series of fluorescent dyes doped in co-host emitter (CHE) systems of TBQ/poly(N-vinylcarbazole) (PVK) can achieve a higher luminescent efficiency and brightness than the other materials. Present research work shows that when TBQ''s concentration is 30%, the maximum EL efficiency is 6.1cd/A at 40mA/cm2. [Copyright &y& Elsevier]

Abstract: ZrO2 ceramics usually have nonuniform microstructures due to the agglomeration of fine ZrO2 powders. In this paper, the thermal conductivity of porous ZrO2 ceramics with different microstructures was investigated by the laser-flash method. It was found that the thermal conductivity of porous ZrO2 ceramics with uniform microstructure was clearly lower than that of ceramics with nonuniform microstructure. Scanning electron microscopy observations showed that porous ceramics with nonuniform microstructures have wider pore and grain size distributions, relative to those with uniform microstructures. Theoretical analyses were done to model the thermal conductivity of porous ceramics using an effective medium approach. These analyses revealed that matrix grain size distribution has a significant impact on the thermal conductivity of porous ceramics, while the effect of pore size distribution is negligible. [Copyright &y& Elsevier]

Previous experiments showed that γ-Al2O3-modified Al powder could continuously react with water and generate hydrogen at room temperature under atmospheric pressure. In this work, a possible physicochemical mechanism is proposed. It reveals that a passive oxide film on Al particle surfaces is hydrated in water. OH− ions are the main mobile species in the hydrated oxide film. When the hydrated front meets the metal Al surface, OH− ions react with Al and release H2. Because of the limited H-soluble capacity in small Al particles and the low permeability of the hydrated oxide film toward H+ species, H2 molecules accumulate and form small H2 gas bubbles at the Al:Al2O3 interface. When the reaction equilibrium pressure in H2 bubbles exceeds a critical gas pressure that the hydrated oxide film can sustain, the film on the Al particle surfaces breaks and the reaction of Al with water continues. As the surface oxide layer on modified Al particles has a lower tensile strength, the critical gas pressure in H2 bubbles is lower so that under an ambient condition, the reaction of modified Al particles with water is continuous. The proposed mechanism was further confirmed by a new experiment showing that the as-received Al powder could continuously react with water at temperatures above 40°C and under low vacuum, because the vacuum makes the critical gas pressure in H2 bubbles decrease as well. [ABSTRACT FROM AUTHOR]

Abstract: Organic light-emitting diodes with ultra thin Rubrene layer have been fabricated with the structure of ITO/hole-transport layer/Rubrene/AlQ/LiF/Al. The hole-transport layer are copper phthalocyanine (CuPc), poly(3,4-ethylenedioxythiophene) doped with polystrenesulphonic acid (PEDOT: PSS), poly(N-vinyl carbazole) (PVK), and N,N′-diphenyl-N,N′-bis(1,1′-biphenyl)-4,4′-diamine (NPB), respectively. Compared with the other two devices, when 5,6,11,12-tetraphenylnaphthacene (Rubrene) is inserted between PVK (or NPB) and tris(8-quinolinolato)aluminum (AlQ), Rubrene’s emission get enhanced. The energy transfer mechanism among PVK (NPB), AlQ and Rubrene are revealed by the absorption and emitting spectra. Moreover, the enhancement of Rubrene’s emission can also be ascribed as an organic quantum well structure’s trap effection. [Copyright &y& Elsevier]

A unidirectional porous glass structure coated with a nanometer TiO2 thin film on pore walls was successfully fabricated by a two-step process. Firstly, a water-based slurry of sheet glass was frozen while controlling the growth direction of ice crystals, and then sublimation of the ice under vacuum formed the green body. The green body was subsequently sintered to produce porous glass with unidirectional pores. Secondly, the sintered porous glass was infiltrated by a titanium (IV) butoxide solution, and then dried and calcined at a moderate temperature to generate a nanometer TiO2 film on pore walls. The present porous glass with nanometer TiO2 has more total surface area than the TiO2 film on glass plates, which is believed to be more effective in the phtotocatalysis application for air or water purification. [ABSTRACT FROM AUTHOR]

Abstract: Organic light-emitting diodes (OLEDs) with multiple hole-trapping-layer (HTL) structures, which consist of N,N′-bis-(1-naphthyl)-N, N′-diphenyl-1,1′-biphenyl 4,4′-diamine (NPB), bathocuproine (BCP) and tris(8-hydroxy-quinoline)aluminum (Alq3) have been fabricated. The emitting zone of the device with the structure of ITO/[NPB/BCP] n /Alq3/LiF/Al can be changed by the number n of HTL. The effect of the multiple HTL structure upon the performance of OLEDs with tris(8-hydroxyquinoline) aluminum as the emitting material has been investigated. Compared with the brightness of the conventional green emitting diode without the multiple HTL structure, that of the diode with periodic number of five has been increased from 2512.8cd/m2 to 8661.0cd/m2. Such an improvement in the device performance was attributed to the improved hole–electron balance, which can be further attributed to the introduction of the multiple HTL structure. [Copyright &y& Elsevier]