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CdS decorated artificial leaf BiVO4/InVO4 Z-scheme heterogeneous photocatalyst (BiVO4/InVO4 @ CdS) was synthesized for the first time by “Biological Template (BT)”-“Dipping Calcination (DC)”-“Successive Ionic Layer Adsorption and Reaction (SILAR)” method. The as-prepared BiVO4/InVO4 @ CdS exhibits excellent photocatalytic activity and stability for the degradation of biological hydrogen production wastewater and simultaneous production of hydrogen (H2), that can be attributed to its ascendant leaf-liked structure and Z-scheme heterogeneous composition. Furthermore, the possible mechanism of simultaneous H2 production and organic pollution oxidation in biological hydrogen production wastewater was proposed.

Electrical neural interfaces serve as direct communication pathways that connect the nervous system with the external world. Technological advances in this domain are providing increasingly more powerful tools to study, restore, and augment neural functions. Yet, the complexities of the nervous system give rise to substantial challenges in the design, fabrication, and system-level integration of these functional devices. In this review, we present snapshots of the latest progresses in electrical neural interfaces, with an emphasis on advances that expand the spatiotemporal resolution and extent of mapping and manipulating brain circuits. We include discussions of large-scale, long-lasting neural recording; wireless, miniaturized implants; signal transmission, amplification, and processing; as well as the integration of interfaces with optical modalities. We outline the background and rationale of these developments and share insights into the future directions and new opportunities they enable.

BACKGROUND Hemorrhagic shock could induce acute lung injury (ALI), which is associated with cell hypoxia, lung tissue inflammation, free radical damage, and excessive cell apoptosis. Our previous studies demonstrated that hyperoxygenated solution could alleviate cell hypoxia. Furthermore, hydrogen-rich solution (HS) could relieve lung tissue inflammation, free radical damage and excessive cell apoptosis. Therefore we hypothesize that Hyperoxygenated Hydrogen-rich solution (HOHS) can protect the lung against ALI. MATERIALS AND METHODS SD rats were randomly divided into five groups (n = 6 at each time point in each group) and were exposed to Hemorrhagic shock induced ALI, and then treated with lactated Ringer's solution (LRS), hyperoxygenated solution, HS, and HOHS, respectively. The protective effects of these solutions were assessed using methods as follows: arterial blood samples were collected for blood gas analysis; Bronchoalveolar lavage fluid was collected for cell count and protein quantification; lung tissue samples were collected to measure wet/dry ratio, as well as levels of T-SOD, MDA, TNF-α, and IL-6; Caspase-3 and TUNEL-positive cells, and pathological changes were observed under light microscope; ALI was scored using the Smith scoring method; ultrastructural changes of lung tissues were further observed with transmission electron microscopy. RESULTS The results indicated that PaO2, PaCO2, and T-SOD increased in the three treatment groups (P

Gesture recognition has attracted great attention owing to its applications in many fields such as Human Computer Interaction. However, in video-based gesture recognition, some gesture-irrelevant factors like the background handicap the improvement of recognition rate. In this paper, we propose an effective 3D Convolutional Neural Network based method for large-scale gesture recognition using RGB-D video data. To obtain compact but with sufficient motion path information data for the network, the inputs are unified into 32-frame videos first. Then the optical flow images are constructed from the RGB videos frame by frame, to help with eliminating the disturbing background inside them. After that, the spatiotemporal features of de-background RGB and depth data are extracted with the C3D model (a 3D CNN model) respectively and blended together in the next stage according to the discriminant correlation analysis to boost the performance. Finally the classes are predicted with a linear SVM classifier. Our proposed method achieves 54.50% accuracy on the validation subset and 60.93% on the testing subset of the Chalearn LAP IsoGD dataset, both of which outperform our results (ranked 1st place) in the Chalearn LAP Large-scale Gesture Recognition Challenge.

Rational design of all-solid-state Z-scheme heterojunction with advanced structure is essential for boosting photocatalytic efficiency. Herein, we design and fabricate a novel Z-scheme photocatalyst with leaf architecture (named artificial leaf) via a simple dipping-calcination (DC) process followed by a successive ionic layer adsorption and reaction (SILAR) strategy. The prepared artificial leaf, composing of CdS, InVO

A modified quick, easy, cheap, effective, rugged, and safe extraction procedure combined with ultra-performance liquid chromatographic separation and ion mobility quadrupole time-of-flight mass spectrometry was developed to determine the presence of 20 mycotoxins (i.e., Alternaria toxins, ochratoxin, patulin, aflatoxin and trichothecenes) in fruit samples from Xinjiang. A complete platform, including screening via an in-house library, confirmation and quantification using reference standards, was established, which provided accurate MS data and complete spectra containing the fragment ions for each analyte. To evaluate the performance of the developed method, satisfactory validation parameters, such as linearity (R2 ≥ 0.9992), precision (RSDs ≤ 9.8%), recovery (81.2–99.2%), LOD (0.06–2.22 µg kg−1), and LOQ (0.2–7.39 µg kg−1), were obtained. The analysis of 130 fruit samples revealed nonnegligible contamination with mycotoxins; specifically, the highest levels of three Alternaria toxins were detected in jujube, wolfberries and raisins.

Indium vanadate (InVO4) is an up-and-coming semiconductor photocatalyst for energy/environment-related applications, and has attracted tremendous attention in the last few decades, owing to its suitable band gap, high thermal and chemical stability, and outstanding photocatalytic performance. However, the low solar-energy utilization efficiency of InVO4 material constrains its further development, mainly due to the sluggish separation and migration kinetics of charge carriers. Fortunately, recent breakthroughs have been achieved in both enhancing the efficiency and clarifying the underlying mechanism for photocatalytic applications. Therefore, it is necessary and urgent to summarize these research efforts and breakthroughs upon InVO4-based nanomaterials to improve the photocatalytic efficiency and speed up the commercialization. In this review, we systematically summarize the recent experimental and computational developments of the modifications of InVO4-based photocatalysts by morphology control, element doping, and hetero-junction construction. Then, we give an overview of their promising photocatalytic applications. Finally, the perspectives on the challenges faced and potential future research directions on InVO4-based photocatalysts is given. We aim to provide guideline for the rational design and fabrication of high efficient InVO4-based photocatalysts for energy and environmental applications.

Background Premenstrual syndrome (PMS) is characterized by a series of emotional, physical and behavioral symptoms. Although PMS is related to dysfunctions of the central nervous system, the neuropathological mechanism of PMS still has not been clearly established. The aim of this study is to evaluate potential differences in both cortical thickness and subcortical volumes in PMS patients compared to healthy controls (HCs). Methods Twenty PMS patients and twenty HCs underwent a structural magnetic resonance imaging scan and clinical assessment. Cortical thickness and subcortical volumes were computed using the FreeSurfer image analysis suite. Relationships between cortical thickness/subcortical volumes and the daily rating of severity of problems (DRSP) score were then measured in patients. Results Compared to HCs, PMS patients exhibited reduced cortical thickness in the medial prefrontal cortex (MPFC), orbitofrontal cortex (OFC) and insula, and increased subcortical volumes of the amygdala, thalamus and pallidum. Furthermore, negative correlations were detected between the DRSP and cortical thickness in the anterior cingulate cortex and precuneus. Limitations The study is limited by a small sample size and narrow age range of participants. Conclusions Our findings indicate that the abnormal morphological changes are mainly implicated in emotional regulation and visceral perception in PMS patients. We hope that our study may contribute to a better understanding of PMS.

Photocatalytic oxidation of methane into formaldehyde in high yield and selectivity remains a grand challenge due to the ineluctable intermediates. Here, we report that a {001}, {010} and {100} facets modified tungsten trioxide photocatalyst enables an intermediate-free oxidation of methane into formaldehyde with 99.4% selectivity. A durable formaldehyde yield of 4.61 mmol g−1 can be achieved after irradiation for 30 h. Mechanism studies disclose that surface defect and reactive lattice oxygen atom are crucial for the selectivity and productivity promotion. This work provides a valid paradigm for efficient conversion of methane to formaldehyde.

In this work, we successfully constructed a highly efficient Z-scheme ZnIn2S4-NiO/BiVO4 photocatalytic system and reported a breakthrough study that has uncovered the photocatalytic reaction mechanism and pathway of hydrogen (H2) evolution and simultaneous formaldehyde (HCHO) degradation over the as-prepared Z-scheme photocatalytic system. By exploring the effects of oxygen (O2) and pH on the photocatalytic activity of the Z-scheme photocatalytic system, it was found that O2 and alkalinity are necessary for photocatalytic HCHO degradation and H2 production. O2 can boost the oxidation conversion of HCHO into formic acid (HCOOH) and restrain the HCHO polymerization reaction, therefore accelerate the formation of H2 in the reaction system. With the increase of pH value from 4 to 13, the reducibility of HCHO and the electronegativity of catalyst increase, which makes the activity of catalyst system increase. The results provide a new route for the optimization of reaction conditions for simultaneous photocatalytic H2 production and HCHO degradation. Under the optimal conditions (80% of O2, 13 of pH and 1.5 mol·L−1 of HCHO initial concentration), the best H2 production activity and HCHO degradation activity are 2724.89 μmol·h−1 and 17.00 mmol·h−1, respectively. On this basis, the possible pathway and mechanism of photocatalytic H2 production and simultaneous HCHO degradation were proposed, which shed lights on elucidating the reaction path and underlying mechanism for photocatalytic H2 production and pollutant degradation.

In order to reduce the energy consumption and improve the economy of air conditioning system, theoretical analysis and energy consumption simulation are used in this paper to explore the adaptability of temperature and humidity independent control (THIC) air-conditioning system in green office buildings. On the basis of the air moisture content and working hours of staff in green office buildings, China was divided into four humidity-hour zones, and several typical cities were selected in each zone for the same building to carry out the analyses of energy consumption simulation and dynamic recovery period of different THIC air conditioning systems in office buildings. The results indicated that in Urumqi, as the representative city of humidity-hour zone I, green office buildings do not suit THIC system; THIC air conditioning system shows obvious advantages over traditional air conditioning in terms of energy saving and economy, and the energy saving rate of the most suitable THIC air conditioning system in Harbin, Beijing and Haikou, as the representative city of humidity-hour zone Ⅱ, zone Ⅲ and zone Ⅳ, reached 28.04%, 24.64%, and 24.42% respectively. Based on the number of humidity-hour, the most suitable THIC air conditioning systems for typical cities in different zone were raised, and a reference for the use of THIC air conditioning system in green office buildings was provided in this paper.

Intestinal protozoan pathogens cause significant diarrhoeal diseases in children. However, to date, there has been limited genetic study of the intestinal pathogens Cryptosporidium, Giardia and Enterocytozoon in humans in China, with the exception of research in a small number of cities/provinces. In the present study, PCR-based tools were used to detect and characterise these protistan parasites from 500 children with a history of diarrhoea in Wuhan and environs, Hubei province, China. Genomic DNAs from faecal samples were screened for the particular protists by PCR utilising regions in the small subunit (SSU) of the nuclear ribosomal RNA, the 60kDa glycoprotein (gp60), the internal transcribed spacer of nuclear ribosomal DNA (ITS) and/or the triose phosphate isomerase (tpi) genes as markers. Cryptosporidium meleagridis subtype IIIb (10/500, 2.0%), Giardia duodenalis assemblage A (7/500, 1.4%) and Enterocytozoon bieneusi genotype D (1/500, 0.2%) were identified in small percentages of the 500 samples. No significant gender- or age-associated differences in the prevalence of Cryptosporidium and Giardia infections were found. Future studies might focus on the occurrence of these protists in children as well as animals, with an emphasis on Cryptosporidium meleagridis in pets and agriculturally important birds, in different parts of Hubei province.

Objective An amelogenin-derived peptide has been shown to promote remineralization of demineralized enamel in an in vitro model of initial caries induced by pH cycling. The present study examines whether the peptide exerts similar effects within the complex oral environment in vivo. Design Specific pathogen-free Sprague-Dawley rats (n = 36) were infected with Streptococcus mutans, given ad libitum access to Diet 2000 and drinking water supplemented with sucrose (10%, w/v), and then randomly divided into three groups treated with 25 μM peptide solution, 1 g/L NaF or deionized water. Molar teeth were swabbed twice daily with the respective solutions for 24 days. Then animals were killed, their jaws were removed and caries lesions were analyzed using the quantitative light-induced fluorescence-digital (QLF-D) technique to measure changes in mineral content. To verify QLF-D results, caries were scored for lesion depth and size using the Keyes method, and analyzed using polarized light microscopy (PLM). Results Mineral gain was significantly higher in teeth treated with peptide or NaF than in teeth treated with water (p

General indirect transformation of methane into formaldehyde is based on methanol as intermediate yet leading to low selectivity. Herein, we report a direct photocatalytic conversion of methane to formaldehyde over gold modified cuboid-shaped tungsten trioxide with exposed (002), (020) and (200) facets containing crystal-O at room temperature (25 °C). Under light irradiation, high spin state crystal-O− ion as a hole can active C H bond in methane and subsequently be consumed to form formaldehyde, then renovated by the addition of oxygen. Isotopic 13CH4 and 18O2 tests reveal that formaldehyde indeed stems from the combination of methane and crystal-O on the exposed (002), (020) and (200) facets. Besides, metallic gold deposited on the surface of cuboid-shaped tungsten trioxide can extract the photoexcited electrons and further enhance the formation of crystal-O− ions. The productivity of formaldehyde over optimized catalyst can reach 7202 μmol g-1 with approximate 100 % selectivity within 24 h reaction time.

Acetonitrile stacking is an online concentration method that is distinctive due to its inclusion of a high proportion of organic solvent in sample matrices. We previously designed a universal methodology for the combination of liquid-phase microextraction (LPME) and capillary electrophoresis (CE) using acetonitrile stacking and micellar electrokinetic chromatography (MEKC) mode, thereby achieving large-volume injection of the diluted LPME extractant and the online concentration. In this report, the methodology was extended to the analysis of highly substituted hydrophobic chlorophenols in wines using diethyl carbonate as the extractant. Additionally, the mechanism of acetonitrile stacking was studied. The results indicated that the combination of LPME and MEKC exhibited good analytical performance: with ∼40-fold concentration by LPME, a 20-cm (33% of the total length) sample plug injection of an eight-fold dilution of diethyl carbonate with the organic solvent-saline solution produced enrichments higher by a factor of 260-791. Limits of qualification ranged from 5.5 to 16.0ng/mL. Acceptable reproducibilities of lower than 1.8% for migration time and 8.6% for peak areas were obtained. A dual stacking mechanism of acetonitrile stacking was revealed, involving transient isotachophoresis plus pH-junction stacking. The latter was associated with a pH shift induced by the presence of acetonitrile. The pseudo-stationary phase (Brij-35) played an important role in reducing the CE running time by weakening the isotachophoretic migration of the analyte ions following Cl(-) ions. The combination of acetonitrile stacking and nonionic micelle-based MEKC appears to be a perfect match for introducing water-immiscible LPME extractants into an aqueous CE system and can thus significantly expand the application of LPME-CE in green analytical chemistry.

High morbidity and mortality are still associated with lung cancer, especially non-small cell lung cancer (NSCLC). Although several studies showed abnormality in lung cancer lipidome, the underlying mechanism remains unclear. Therefore, a marker for early diagnosis of NSCLC is highly needed. In this study, a nontargeted lipidomics approach based on liquid chromatography-mass spectrometry was used to analyze the lung tumor tissue (LCT) lipidome to investigate the characteristics of lipid metabolism alterations in lung cancer tissues and find suitable lipid markers for lung cancer and its subtypes. Our results revealed that the most prominent alterations in LCT were the decrease of free fatty acid (FFA) and increase of triglyceride compared with distal noncancerous tissue (DNT). We also identified and verified the combinational lipid markers which can discriminate malignant from benign tissue as well as different NSCLC subtypes. These results not only provide hints in the lipid metabolism dysregulations between malignant and benign tissues but also define the combinational lipid markers to aid clinical diagnosis of lung cancer and its subtypes.

The unique C@Ti4O7/g-C3N4 photocatalyst was synthesize via wet chemical and annealing & calcining method, which was gifted both the intrinsic oxygen vacancies as well as Z-scheme heterojunction nature in structure. Such a unique three-dimensional structure exhibited exceptional photodegradation performance for the dye simulations system (Rhodamine B (RhB), methylene blue (MB) and methyl orange (MO)) under visible light irradiation, which is better than a single component and Anatase-TiO2. Subsequently, a possible photocatalytic Z-scheme mechanism was proposed to further illustrate the effective separation of photogenerated electron-hole pairs in C@Ti4O7/g-C3N4 based on structure and electrochemical characterizations results, which will help to better understand the nature of Z-scheme heterojunctions.

Jujube is widely grown in Xinjiang province, China, including two high-value PGI products, Charkhlik Hui jujube and Khotan Jun jujube. Origin mislabeling and substitution of PGI jujube by inferior products seriously harms their reputation and has potential food safety risks. In this study, stable isotope (δ13C, δ15N, δ2H, δ18O) and elemental (Na, Mg, Al, P, K, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Sr, Mo, Cd, Sb, Ba, Pb) compositions of jujube from five different regions across Xinjiang province were analyzed by orthogonal partial least squares-discriminant analysis (OPLS-DA) to verify the geographical origin of jujube and authenticate PGI products. A total of 167 Hui jujube and 156 Jun jujube samples, together with their associated soils were collected annually from 2013 to 2018. The regional, varietal and inter-annual differences of stable isotope and elemental compositions of jujube and their correlation with soil values were analyzed using one-way ANOVA and multivariate statistics. The discriminant accuracies of OPLS-DA modeling for both Hui and Jun jujube samples collected in 2016 were higher than 90 %. Over a longer five-year (from 2013 to 2018), the discriminant accuracies decreased slightly, but were still acceptable at 85 % and 75 % for the two varieties. The most important variables for discrimination models were Na, Al, Ba, and δ13C for Hui jujube, δ18O and δ15N for Jun jujube, respectively. The study show that this strategy holds good promise as a tool to combat mislabeling and fraudulent conduct and has the ability to protect PGI jujube produced in Xinjiang province.

In this work, a series of δ-MnO2/USY with different contents of δ-MnO2 (0.3 wt%, 1.5 wt%, 3.0 wt%, 10.0 wt%, and 15.0 wt%) were prepared. In addition, their performances of the adsorption of toluene, degradation and mineralization of toluene, and removal of ozone (O3) were investigated. The results showed that, among all the samples, 3.0 wt% δ-MnO2/USY displayed the best performance of toluene adsorption, degradation and mineralization. Furthermore, according to the in situ DRIFTS and GC-MS analysis, the intermediate by-products during the toluene degradation progress were ascertained and the possible pathway of catalytic oxidation toluene by δ-MnO2/USY in the presence of O3 was proposed.

A novel BT-DCCOC method for in situ one-step preparation of carbon-modified BiVO4 with leaf-liked structures (artificial leaf) was developed. This strategy provides a new way for the preparation of C-modified photocatalyst (using biological template and controlling oxygen content in calcination atmosphere), and realizes the synchronous control of bionic structure and carbon modification. The leaf-liked structures and morphologies of the prepared samples were observed by the FE-SEM and TEM observations. The content of residual carbon, which was formed in-site by adjusting the oxygen content in the calcination atmosphere, was measured by TG-DSC. The photocatalytic activities of the samples were evaluated by the degradation of RhB. The results showed that the artificial leaf synthesized at 3 % oxygen content with a carbon content of 6.32 wt% demonstrated the best photocatalytic degradation activity. The improved photocatalytic performance can be attributed to the combination of unique morphology and carbon modification control.

Inspired by the structure of natural leaves in the process of photosynthesis, in this work, artificial leaf BiVO4/InVO4 heterojunction was synthesized by one-step dipping-calcination method, using Chongyang wood seedling as template, and the molar ratio of BiVO4 to InVO4 was optimized. The unique leaf-liked structure of artificial leaf BiVO4/InVO4 was observed by FESEM observations. The photocatalytic activities of artificial leaf BiVO4/InVO4 were evaluated by the degradation of RhB. The results showed that the as-fabricated artificial leaf BiVO4/InVO4 heterojunction with appropriate In, Bi ratio has higher photocatalytic activity than artificial leaf BiVO4 and artificial leaf InVO4. Furthermore, the possible photocatalytic mechanism of artificial leaf BiVO4/InVO4 heterojunction was proposed. This strategy realizes the combination of bionic structure design and heterojunction construction, which enlightens people for the design of highly efficient photocatalytic materials.

In terms of constraining the list assignment, one refinement of k-choosability is considered as choosability with separation. We call a graph (k, d)-choosable if it is colorable from lists of size k where adjacent vertices have at most d common colors in their lists. If two cycles have exactly one common edge, then they are said to be normally adjacent. In this article, it is shown that planar graphs without 5-cycles and normally adjacent 4-cycles are (3,1)-choosable. This extends a result that planar graphs without 5- and 6-cycles are (3,1)-choosable (Choi et al. (2016))

In this work, the first example of isolation and determinations of the cobalt (II) tetraphenylporyphyrin carbene [Co(TPP) (1,3-Me2Imd)] and a new Mn(II) analogue [Mn (TPP) (1,3-Me2Imd)] have been reported. Spectroscopic studies and comparisons with related analogues have determined low spin S = 1/2 state of the Co(II) complex and given deep insights into the behaviors of NHCs as axial ligands of metalloporphyrins. The work would push forward the research and application of these species as dyes and sensitizers.

Different graphene size can affect the catalytic activity of the photocatalyst. In this work, a series of ZnIn2S4/graphene catalysts with different graphene sizes were synthesized, characterized and their photocatalytic activities were evaluated by photocatalytic hydrogen evolution. The different sizes (k) of graphene can be separated by differential centrifugation, with the decrease of graphene size, the activity of hydrogen production of the catalyst under visible light increases first and then decreases, when k = 5–7 μm, the maximum hydrogen production rate was 40.85 μmol/g·h. Furthermore, the relationship between the photocatalytic hydrogen production activity of ZnIn2S4/graphene and its physicochemical properties were further analyzed.

Heterogeneous treatment effects are the center of gravity in many modern causal inference applications. In this paper, we investigate the estimation and inference of heterogeneous treatment effects with precision in a general non-parametric setting. To this end, we enhance the classical $k$-nearest neighbor method with a simple algorithm, extend it to a distributional setting, and suggest the two-scale distributional nearest neighbors (DNN) estimator with reduced finite-sample bias. Our recipe is first to subsample the data and average the 1-nearest neighbor estimators from each subsample. With appropriately chosen subsampling scale, the resulting DNN estimator is proved to be asymptotically unbiased and normal under mild regularity conditions. We then proceed with combining DNN estimators with different subsampling scales to further reduce bias. Our theoretical results on the advantages of the new two-scale DNN framework are well supported by several Monte Carlo simulations. The newly suggested method is also applied to a real-life data set to study the heterogeneity of treatment effects of smoking on children's birth weights across mothers' ages.

A very simple, fast and environmentally friendly sample extraction method was proposed for the analysis of phthalate esters (PAEs, di-isobutyl phthalate (DIBP), dibutylphthalate (DBP), butylbenzylphthalate (BBP) and bis(2-ethylhexyl)phthalate (DEHP)) in alcoholic beverages by using conventional ionic liquid dispersive liquid-liquid microextraction. The samples were extracted by 160 μL 1-octyl-3-methylimidazolium hexafluorophosphate in the presence of appropriate amount of ethanol and 10% (w/v) sodium chloride solution; the enriched analytes in sedimented phases were analyzed by high performance liquid chromatography-diode array detector (HPLC-DAD). Under the optimum conditions, a satisfactory linearity (in the range of 0.02-1 μg mL(-1) for white spirits and 0.01-0.5 μg mL(-1) for red wines with the correlation coefficients (r) varying from 0.9983 to 1), acceptable recovery rates (88.5-103.5% for white spirits and 91.6-104.6% for red wines), good repeatability (RSD ≤ 8.0%) and low detection limits (3.1-4.2 ng mL(-1) for white spirits and 1.5-2.2 ng mL(-1) for red wines) were obtained. The developed method was successfully applied for the determination of the four PAEs in 30 white spirits and 11 red wines collected locally, and the DBP content in 63% (19:30) white spirits exceeded the specific migration limit of 0.3 mg kg(-1) established by international regulation.

Selenium nanoparticles (SNP) were generally utilized as chemotherapeutic agents and environmental ameliorants, but without simultaneous biocontrol functionalities against fungal pathogens and mycotoxins, plus unknown recognition mechanism. Selenium nanoparticles derived from Trichoderma harzianum JF309 (TSNP) were herein synthesized, contrast to traditional SNP, where diverse metabolites co-occurred in TSNP including organic acids and their derivates, such as psoromic acid, β-decyloxybenzoic acid, glucaric acid lactone, etc., revealed by Triple TOF UPLC/HRMS. As hypothesized, this interaction of diverse recognition metabolites and selenium nanoparticles in TSNP might change the arrangement and movement of original state, form random, nondirective to regulated, directional, thus contributing to better antifungal effects and dramatically increasing control functionalities against Alternaria toxins (83% of TeA and 79% of AOH reduction), fumonisin B1 (63% of FB1 reduction) and deoxynivalenol (76% of DON reduction), respectively. Meanwhile, expression of key biosynthetic genes of FUM1, PA, TRI5 and TRI6 were substantially decreased. Finally, as convinced, the obtained nanoparticles had no significant side effects to the selected three human cells. In total, the achieved data supports the biogenic nanoparticles as valuable functional materials with great potential for practical plant protection and food safety prevention.

In recent years, using graphene to modify BiVO4 has become a research hotspot. However, there are few reports on the effects of the graphene size and the loading content on the photocatalytic activity of the graphene-modified BiVO4. In this work, a series of BiVO4 photocatalysts modified by oxide graphene (GO) of different sizes and loadings were prepared, characterized and their activities were investigated. The results showed that when the size of GO was 5–7 μm and the loading was 0.5 wt%, the phenol degradation rate over the GO-modified BiVO4 was the best and reached 65.2% after 5 h visible light irradiation.

High dimensionality comparable to sample size is common in many statistical problems. We examine covariance matrix estimation in the asymptotic framework that the dimensionality $p$ tends to $\infty$ as the sample size $n$ increases. Motivated by the Arbitrage Pricing Theory in finance, a multi-factor model is employed to reduce dimensionality and to estimate the covariance matrix. The factors are observable and the number of factors $K$ is allowed to grow with $p$. We investigate impact of $p$ and $K$ on the performance of the model-based covariance matrix estimator. Under mild assumptions, we have established convergence rates and asymptotic normality of the model-based estimator. Its performance is compared with that of the sample covariance matrix. We identify situations under which the factor approach increases performance substantially or marginally. The impacts of covariance matrix estimation on portfolio allocation and risk management are studied. The asymptotic results are supported by a thorough simulation study., Comment: 43 pages, 11 PostScript figures

We propose a new nonparametric test for detecting the presence of jumps in asset prices using discretely observed data. Compared with the test statistic in A\"{i}t-Sahalia and Jacod (2007), our new test statistic enjoys the same asymptotic properties but has smaller variance. These results are justified both theoretically and numerically. Thanks to the reduction of the variance, we also propose a new test procedure to identify the locations of jumps. The problem of jump identification thus reduces to a multiple comparison problem. We employ the False Discovery Rate (FDR) approach to control the type I error. Simulation studies and real data analysis further demonstrate the power of the newly proposed test method.

High dimensionality comparable to sample size is common in many statistical problems. We examine covariance matrix estimation in the asymptotic framework that the dimensionality p tends to infinity as the sample size n increases. Motivated by the Arbitrage Pricing Theory in finance, a multi-factor model is employed to reduce dimensionality and to estimate the covariance matrix. The factors are observable and the number of factors K is allowed to grow with p. We investigate impact of p and K on the performance of the model-based covariance matrix estimator. Under mild assumptions, we have established convergence rates and asymptotic normality of the model-based estimator. Its performance is compared with that of the sample covariance matrix. We identify situations under which the factor approach increases performance substantially or marginally. The impacts of covariance matrix estimation on portfolio allocation and risk management are studied. The asymptotic results are supported by a thorough simulation study.