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Transparent photodetectors (PDs) based on binary metal oxides have become a hot topic in the field of photodetection because of their ability to absorb and detect ultraviolet (UV) light. However, PDs constructed with pure binary metal oxides still have the problems of slow response time and high-voltage drive. In addition, due to its natural internal defects, it has the characteristics of an n-type semiconductor and is difficult to achieve p-type conversion. In this work, the top layer of the device is polyoxometalate (POM) modified ZnO NWs which showed the characteristics of p-type semiconductors, its UV absorption was increased by 36.9%, and the bottom layer of the PD is pure ZnO NWs. An interlayer p–n junction is formed between the two layers, which is not only conducive to carrier transmission, but also can complete photodetection without bias. The PD has a transparency of more than 70% in the visible light region. Under the conditions of zero bias and AM 1.5 illumination, the light–dark current difference (ΔI) reaches 23.76 μA, and the rise-fall time is 1.32 s/2.62 s, respectively. After 216 hours of cycling, it still maintains 70% of the original efficiency.

Accurate topology is the basis of fine management and safe operation of distribution network. With the development of distributed generation, more and more users participate in the distribution network, which makes the flow direction of distribution network more complex and brings some difficulties to the topology identification of distribution network. The existing distribution network topology identification methods lack of multi period measurement data, and the utilization rate of multi-user data is low, which leads to the low accuracy of distribution network topology identification. To solve this problem, a distribution network topology identification method based on multi-user fusion data is proposed. Firstly, the existing distribution network measurement system is analyzed, and the data and characteristics that can be collected in the actual project are obtained. Then, according to the characteristics of different data sampling frequency and accuracy, multi-user data fusion is carried out, and a PMU based multi-user data time scale alignment method and a pseudo measurement generation method based on linear extrapolation are proposed. Finally, an optimization model of distribution network topology identification based on multi-user and multi period fusion data is proposed. By minimizing the error between the measured value and the estimated value in several time periods, the model realizes the identification of distribution network topology. Simulation results show that the method is correct and effective.

A stable cubic phase remained by entropy engineering design with Ba, La and Nb doping. The optimized configurational entropy range, 9–10 J mol−1 K−1, is found and helps to obtain good thermoelectric performance for Sr0.9−xBaxLa0.1Ti0.9Nb0.1O3−δ.

Environment-friendly co-doped CsBr nanocrystals with controllable dual-emission and chrominance have been successfully prepared by using facile one-pot colloidal synthesis approach.

HighlightsA noncontact mechanical wheat seed shooting device was developed for use in the North China Plain.The shooting depth increased with increasing shooting velocity and with increasing shooting angle.The tested parameters were statistically significant for average shooting depth (ASD), coefficient of variation of shooting depth (CVSD), and coefficient of variation of seeding amount (CVSA).The results from bench and field experiments indicated that the performance of the shooting device with the optimized parameters could fully meet the planting requirements for winter wheat in the North China Plain.Abstract. Planting performance is essential for wheat planters and seed emergence. In this study, a noncontact mechanical wheat seed shooting device was developed to simplify the planter structure, eliminate blockage of the soil-contacting parts, and enhance the stability of the sowing depth. A preliminary model of shooting wheat was developed using DEM software to simulate the shooting depth. The modeling results showed general trends of increased shooting depth with increasing shooting velocity and shooting angle, and decreased shooting depth with increasing shooting height. The shooting depth exceeded 30 mm when the shooting velocity of the wheat seeds was greater than 30 m s-1 and the shooting height was less than 150 mm. Additionally, to increase the stability of the sowing depth, this study investigated the effects of three operating parameters (forward speed, rotational speed of the shooting device, and shooting height) on the average shooting depth (ASD), shooting velocity of seed (SVS), coefficient of variation of shooting depth (CVSD), and coefficient of variation of seeding amount (CVSA). The SVS was proposed as an indicator of shooting performance. A three-factor central-composite experiment was performed to understand the parameter interactions and verify the optimal parameter values. The results from bench and field experiments demonstrated that the performance of the shooting device with the optimized parameters could fully meet the sowing requirements for winter wheat in the North China Plain. The ASD, CVSD, CVSA, and SVS of the seed shooting device with the optimized parameters were 34.6 mm, 9.3%, 13.9%, and 35.8 m s-1, respectively. The seed damage rate (SDR), seed germination rate (SGR), and coefficient of variation of seeding uniformity (CVSU) in the field experiment were 0.9%, 88.2%, and 13.5%, respectively. Keywords: Coefficient of variation of shooting depth, Shooting device, Shooting velocity, Winter wheat.

An ordered water bilayer structure was identified on a rutile TiO2(110) surface at ambient temperature by combining VSFG experiments and MD simulations, which well explained the long-time controversy on the wetting behaviors of the TiO2 surface.

Graphitic carbon nitride (g-C3N4) nanosheets exfoliated from their bulk-sized counterparts are limited by a quantum size effect-induced widened bandgap.

In order to satisfy the needs of electronic industries for high-reliability joints, different kinds of nanoparticles were incorporated into conventional Pb-free solders to enhance the performance of solder joints by researchers for decades. It is reported that doping certain nanoparticles to the solder can promote the wettability and strength of the solder, refine the grain size of solder and intermetallic compounds, and inhibit IMC layer growth. In this paper, the effects and the corresponding mechanism of nanoparticle addition on the reliability of Sn-based Pb-free solder joints in various conditions are comprehensively analyzed and summarized such as under thermal aging, thermal cycling, thermal shock, electromigration and so on. In addition, directions for future study about the reliability of nanoparticles-doped solder joints were discussed, so as to provide theoretical support for developing high-reliability nanocomposite solder joints.

The HIV-1 provirus mainly consists of internal coding region flanked by the 2 same long terminal repeats (LTRs) at each terminus. The LTRs play important roles in HIV-1 reverse transcription, integration, and transcription by the association with host factors. However, despite of the significant study advances of the internal coding regions of HIV-1 by using definite reference classification, there are no systematic classifications for HIV-1 5’ LTRs, which hinders our elaboration on 5’ LTR and a better understanding of the viral origin, spread and therapy. Here, by analyzing all available resources of 5’ LTR sequences in public databases following 4 recognized principles for the reference classification, 83 representatives and 14 consensus sequences were identified as representatives of 2 groups, 6 subtypes, 6 sub-subtypes, and 9 CRFs. To test the reliability of our established classification system, the constructed references were applied to identify the 5’ LTR assignment of the 22 clinical isolates in China. The results revealed that 16 out of 22 tested strains showed a consistent subtype classification with the previous LTR-independent classification system. However, 6 strains, for which recombination events within 5’ LTR were demonstrated, unexpectedly showed a different subtype classification, leading a significant change of binding sites for important transcription factors including SP1, p53, and NF-κB. The binding change of these transcriptional factors would probably affect the transcriptional activity of 5’ LTR. This study established a unified classification system for HIV-1 5’ LTRs, which will facilitate HIV-1 characterization and be helpful for both basic and clinical research fields.IMPORTANCEHere, a scientific, reliable, and usable classification system based on the 5’ LTR sequences was established, which will allow us to effectively facilitate the precise typing of HIV-1 strains. This classification system was applied to 22 HIV-1 strains circulating in China, we found that 6 out of 22 strains analyzed, belonged to a different subtype when our results were compared to those obtained with the previous LTR-independent classification system. Thus, these data demonstrated that our classification method could greatly improve the HIV-1 subtype classification. We found that 6 5’ LTR sequences showed recombination events, leading to a significant exchange of the binding sites of transcriptional factors. Thus, this work established a comprehensive HIV-1 5’ LTR classification system, which will help the scientific community to precisely characterize HIV-1 variants, and better understand the origin and spread of HIV-1 strains, and it also may be helpful for pathogenicity and transmissibility evaluation studies.

Cu-based quaternary chalcogenide compounds have been thermoelectric topic of interest among researchers, especially in recent years, due to their intrinsically low thermal conductivity. Recently plenty of work is done on thermoelectric properties of Cu2ZnSnSe4-based alloys emphasizing on importance of Cu2ZnSnSe4-based alloys in thermoelectric power generation. In this study, we report the effect of annealing temperature on microstructure and thermoelectric properties of Cu2.1Zn0.9SnSe4 alloys. Cu2.1Zn0.9SnSe4 compounds were synthesized by high-temperature melting followed by annealing at four different temperatures (600 °C, 650 °C, 700 °C and 725 °C). X-ray diffraction combined with Raman spectroscopy confirmed the presence of Cu2ZnSnSe4 phase along with ZnSe and CuSe secondary phases. The increased annealing temperature critically affected the microstructure of Cu2.1Zn0.9SnSe4 alloys. Successive increase in annealing temperature subsequently increases the average grain size from 7.3 for 600 sample to 12.1 μm for 725 °C sample by shifting grain size distribution toward higher range. Increased grain size results in reduced carrier scattering and decreases the electrical resistivity eventually improving power factor and maximum power factor of about 400 μWk−2 m−1 is obtained for 725 °C sample. Besides, the increased annealing temperature resulted in increased thermal conductivity attributing increased grain size resulting in low phonon scattering. 725 °C sample shows highest power factor and moderate thermal conductivity among all the samples which resulted in highest value of figure of merit for 725 °C sample of about 0.1 at 673 K.

Cadmium (Cd) stress can cause system disorders in plants, affect the absorption of some nutrients. The roles and their relationship of salicylic acid (SA) and hydrogen peroxide (H2O2) in adventitious root formation (ARF) of cucumber (Cucumis sativus L.) under Cd stress were studied. The results showed that the exogenous SA and H2O2 in enhancing ARF in cucumber explants under Cd stress was concentration-dependent, with an optimal biological effect at 0.1 µM SA or 50 µM H2O2. Under Cd stress, SA-induced ARF was significantly reversed by H2O2 scavenger and inhibitor, indicating that endogenous H2O2 may be involved in SA-induced ARF under Cd stress. In addition, endogenous H2O2 levels were also promoted by SA in cucumber explants. The application of SA promoted pectin content and decreased pectin methylesterification degree under Cd stress. Moreover, we founded that SA and SA + H2O2 up-regulated the expression level of CsQUA and CsPME under Cd stress, respectively. However, the application of H2O2 scavenger and inhibitor could significantly reverse the effects of SA on the expression of the above genes. These results suggested that SA might play an important role in ARF in cucumber under Cd stress via enhancing endogenous H2O2 levels.

Ketene, a versatile reagent in production of fine and specialty chemicals, is produced from acetic acid. We investigate the synthesis of ketene from acetic acid over the (3,0;1,1) surface of Cu2O(1 0 0) through analysis of the adsorption and desorption characteristics of formic and acetic acids. The results allow us to establish a reaction mechanism for ketene formation. Observations from x-ray photoelectron spectroscopy (XPS), scanning tunneling microscopy, and temperature programmed desorption (TPD), supported by a comparison with formic acid results, suggest that acetic acid reacts with Cu2O through deprotonation to form acetate species coordinated to copper sites and hydroxylation of nearby surface oxygen sites. For formic acid the decomposition of adsorbed formate species results in desorption of CO2 and CO while, for acetic acid, high yields of ketene are observed at temperature >500 K. Modeling by density functional theory (DFT) confirms the strong interaction of acetic acid with the (3,0;1,1) surface and the spontaneous dissociation into adsorbed acetate and hydrogen atom species, the latter forming an OH-group. In an identified reaction intermediate ketene binds via all C and O atoms to Cu surface sites, in agreement with interpretations from XPS. In the vicinity of the adsorbate the surface experiences a local reorganization into a c(2 × 2) reconstruction. The total computed energy barrier for ketene formation is 1.81 eV in good agreement with the 1.74 eV obtained from TPD analysis. Our experimental observations and mechanistic DFT studies suggests that Cu2O can operate as an efficient catalyst for the green generation of ketene from acetic acid., Swedish Research Council (VR); VR Starting Grant; Knut och Alice Wallenbergs stiftelse; STINT Joint China-Sweden Mobility Program; Ragnar Holm Foundation; Trygger’s Foundation; Chalmers Areas of Advance-Materials Science

The surface water from subsidence lakes and shallow groundwater plays an important role for agriculture, industry and local communities in coal mining areas. The connection between the two types of water and quality, however, remains unclear. In this study, 37 samples were collected from a subsidence lake and shallow groundwater around Luling coal mine. The hydrogeochemisty data and formation mechanisms were analyzed to reveal the connection proof. Compared with shallow groundwater, the surface water from the subsidence lake has a higher content of Na+ and HCO3−. For the two types of water samples, Na+ and Mg2+ are two most abundant cations, followed by Ca2+. The contents of anions followed the same order: HCO3− > SO42− > Cl−. The water samples were controlled by NaHCO3 (99.3%) type. The chemical composition of the two types of water were similar, which are all mainly influenced by silicate minerals weathering and ion-exchange interactions, among which ion-exchange interactions were more intense than in shallow groundwater. The recharging source of the two types of water mainly came from atmospheric precipitation. The two waters in the study area, in general, showed the risk of high salt and low-moderate alkali damage. The outcomes provide a better understanding of the subsidence lake and groundwater and it will help utilization of water resources.

Background Pituitary adenoma (PA) accounts for 10–15% of all intracranial neoplasms. Despite their benign nature, PA often shows invasive growth. MicroRNAs (miRNAs) and long non-coding RNAs (lncRNAs) are a class of non-coding RNAs that play important roles in PA initiation and progression. Aim The aim of this study was to find specific profiles of miR-200a and long non-coding RNA (lncRNA) antisense non-coding RNA in the INK4 locus (ANRIL) in PA based on a comparative study using Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) analyses of tumor tissue and plasma. Methods Plasma and PA tissue samples were obtained from two groups of included patients (15 invasive and 15 non-invasive PA). In addition, plasma samples from patients with invasive PA have collected pre- and post-operation. Plasma and tissue samples subjected to qRT-PCR analyses for the expression levels of miR-200a and lncRNA ANRIL. Results The expression levels of miR-200a and lncRNA ANRIL were increased in tissue samples patients with invasive PA than in the patients with non-invasive PA. In addition, the expression levels of circulating miR-200a and lncRNA ANRIL were increased in patients with invasive PA than in patients with non-invasive PA in the pre-operation period. However, the expression level of plasma circulating miR-200a and lncRNA ANRIL was decreased in patients with invasive PA in the post-operation period. Our results depicted a miR-200a and lncRNA ANRIL expression in tissue and plasma samples in the patients with invasive PA. In addition, Receiver Operating Characteristic (ROC) curve was used to evaluate the diagnostic value of these circulating miR-200a and lncRNA ANRIL. Conclusion The expression of these tumor-associated ncRNAs has been elevated in the PAs. Therefore, miR-200a and lncRNA ANRIL represents as biomarkers for diagnosis and potential targets for novel invasive PA treatment strategies.

Faced with multiple pressures from family, study, employment and interpersonal relationship management, college students are more likely to suffer from mental health problems. At present, psychological intervention in China mainly focuses on drugs and interviews, ignoring the important role played by the family as a bio-psycho-social unit, and there are certain cultural compatibility differences. As an important activity in family life, family rituals have been widely used in the treatment of diseases or mental health in western countries. In contrast, in China, the public's attention and application of family rituals are obviously insufficient, and the relevant academic research results are relatively rare. In view of this, this paper adopts mathematical statistics method to clarify the internal relationship between family rituals and subjective well-being of college students, and verify the mediating role of family system in it, so as to provide effective suggestions for psychological health intervention of college students. The results showed that: Family rituals, family system and subjective well-being are correlated in pairs, showing a significant positive correlation; Family rituals and family system have significant predictive effects on subjective well-being of college students; The cohesion and adaptability play part of mediating roles between college students' family rituals and subjective well-being.

Omics techniques provide effective detection tools for assessing the potential impact of plant composition at the DNA, RNA, and protein levels. Among these, protein is the executor of gene function and the embodiment of biological traits, so that organisms show various genetic characteristics. Proteomics can be used to assess whether genetic engineering will lead to changes in plant traits beyond those introduced by conventional plant breeding. Here, we compare the extent of the proteome occurring in the leaves of three transgenic rice restorer lines expressing CRY1C and CRY2A genes developed by genetic engineering and their corresponding recurrent parents developed by conventional breeding. CRY1C and CRY2A genes were inserted into chromosomes 11 and 12, respectively, which significantly improved the resistance of restorer lines to Chilo suppressalis. Although differentially expressed proteins could be distinguished between transgenic rice and its recurrent parents, these differences were not sufficient to cause unintended effects on grain yield and quality traits of transgenic rice. In contrast, differences in phenotypic traits are more because of differences in genetic background. Functional cluster analysis showed that the differentially expressed proteins caused by the insertion of exogenous genes mainly involved signal transduction and secondary metabolites(serine, tryptophan) biosynthesis, transport and catabolism pathways. The study successfully used 4D label-free quantitative proteomics technology to assess the unexpected changes in new rice varieties, and the results showed that transgenic rice did not cause unintended effects.

A lack of stability in the expression of Bacillus thuringiensisgenes (CRY) and the dialaninophosphate resistance gene (BAR) in transgenic rice plants can lead to the loss of important characters. The genetic stability of transgenic expression in high-generation lines is thus critically important for ensuring the success of molecular breeding efforts. Here, we studied the genetic stability of resistance to insect pests and herbicides in transgenic rice lines at the molecular and phenotypic levels in a pesticide-free environment. Southern blot analysis, real-time polymerase chain reaction, and enzyme-linked immunosorbent assays revealed high stability in the copy numbers and expression levels of CRY1C, CRY2A, and BAR in transgenic lines across different generations, and gene expression levels were highly correlated with protein expression levels. The insecticide resistance of the transgenic rice lines was high. The larval mortality of Chilo suppressalis was 50.25% to 68.36% higher in transgenic lines than in non-transgenic control lines. Percent dead hearts and percent white spikelets were 16.66% to 22.15% and 27.07% to 33.47% lower in transgenic lines than in non-transgenic control lines, respectively. The herbicide resistance of the transgenic rice lines was also high. The bud length and root length ranged were 2.53 cm to 4.20 cm and 0.28 cm to 0.73 cm higher in transgenic lines than in non-transgenic control lines in the budding stage, respectively. Following application of the herbicide Basta, the chlorophyll content of the transgenic lines began to recover 2 d later in the seedling and tillering stages and 3 d later in the booting and heading stages, by contrast, the chlorophyll content of the non-transgenic lines did not recover and continued to decrease. These findings revealed high genetic stability of the resistance to insect pests and herbicides across several generations of transgenic rice regardless of the genetic background.

Since traditional fluorescent materials are too easily observed by the eyes just under the UV light, off-on fluorescent materials are explored as the new generation of fluorescent labels. In the "off" state, such off-on fluorescent labels cannot be observed by naked eyes under either natural light or UV light. Only after a specific decryption treatment to make the fluorescent materials turning into the "on" state, the fluorescent labels can be observed under the UV light. Up to now, it is still a challenge to prepare fluorescent inks with aforementioned ideal properties by using halide perovskite materials. Herein, we reported the first example of Te

Hyperperfusion-induced intracerebral hemorrhage (HICH) is a relatively rare but potentially devastating event after carotid artery stenting (CAS). Staged angioplasty (SAP), a two-stage form of CAS, has been shown to be effective for preventing cerebral hyperperfusion syndrome (CHS). The aim of our retrospective single-center study was to investigate the safety and efficacy of SAP to prevent HICH in patients with very severe carotid stenosis (90%-99%) and poor collateral compensation.One hundred and fifty-three patients with severe symptomatic carotid artery stenosis ≥90% between November 2011 and August 2018, 96 were scheduled to undergo regular CAS and 57 were scheduled for SAP. High risk of HICH were considered based on severe stenosis degree (90%-99%) and poor collateral compensation, which were determined using digital subtraction angiography and qualitative CT perfusion. The patients' clinical, procedural information and occurrence of HICH were compared between regular CAS and SAP groups.Fifty-seven patients scheduled for SAP, 3 of them were switched to regular CAS because of intraoperative dissection. The median interval between stages I and II was 8 days (IQR: 4-20 days). One case who switched to regular CAS suffered from HICH. HICH occurred in one patient (1.75%, 1/57) in the SAP group and 12 patients (12.5%, 12/96) in the regular CAS group (OR: 0.117, 95% CI: 0.014-0.990, p=0.049). Multivariate analysis showed that SAP was negatively related to CHS (OR: 0.117; 95% CI 0.014-0.990; p=0.049).SAP is an effective treatment for avoiding HICH in patients with carotid pre-occlusive stenosis (90%-99%) and poor collateral compensation.

In this study, a magnetic iron-zirconium modified zeolite (FeZrMZ) was synthesized. Through sediment culture experiments, the influence of the addition of modified materials on the migration and transformation of phosphorus in river sediments was investigated. The results showed that the modified zeolite could not only effectively reduce the phosphorus concentration in the overlying water, but also significantly reduce the phosphorus concentration in the pore water of sediments. The addition of modified zeolite makes the unstable weakly adsorbed phosphorus (NH4Cl-P) and redox phosphorus (BD-P) transform into the more stable metal oxide-bound phosphorus (NaOH-P) and very stable residual phosphorus (Res-P). The four types of bioavailable phosphorus (BAP), including water-soluble phosphorus (WSP), readily desorbable phosphorus (RDP), algae-available phosphorus (AAP), and NaHCO3 extractable phosphorus (Olsen-P). Under anoxic conditions, they were reduced by 53.5%, 14.1%, 23.8%, and 49.9% respectively. Under aerobic conditions, they were reduced by 23.2%, 16.6%, 32.1%, and 50.0%. The addition of magnetic iron-zirconium modified zeolite could clearly reduce the release potential of phosphorus in sediment, and it could be recovered through the action of an external magnetic field, so it could be used as an effective sediment modifier to control the sediment release of phosphorus. HIGHLIGHTS Synthesize and characterize FeZrMZ, which has a good magnetic separation ability.; FeZrMZ can effectively reduce the concentration of phosphorus in overlying water and interstitial water.; FeZrMZ can convert unstable phosphorus in sediments into stable phosphorus.

Effective treatment strategies for vertebrobasilar dissecting aneurysms (VBDAs) remain controversial due to their high morbidity and mortality. The aim of the present study was to evaluate the efficacy of overlapping stent-assisted coil embolization (OSCE) in VBDA patients. A total of 42 patients with VBDA were retrospectively examined by OSCE from May 2015 to August 2019. Patients' clinical and radiological parameters were assessed at discharge and during interim follow-up. Safety, technical feasibility and follow-up clinical and imaging observations for therapy were also evaluated retrospectively. The average age of the 42 patients who underwent OSCE was 54 years (range 33 to 74 years). Overlapping stents were successfully implanted in all patients after coil embolism. Overall clinical results were effective (score on a modified Rankin scale from 0 to 2) in all patients. In the meantime, all patients had favorable outcomes when evaluating telephone calls or digital subtractive angiography (DSA) imaging. Among 42 patients, one patient died due to a perioperative rupture. All the remaining 41 patients had a good prognosis during the follow-up telephone call, with a median follow-up of 28 months (range, 2 to 55 months). The total number of DSA recurrences was 20. Subsequent DSA results showed that all aneurysms were completely occluded while in only one case the parent artery of the aneurysm was completely closed. OSCE in VBDAs patients is safe and effective. This technique showed favorable results in clinical and imaging follow-ups for non-ruptured and ruptured VBDAs.