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Debris flows are considered one of the most hazardous types of mass movement. China has a long history of monitoring debris flows, which has enhanced the understanding of debris flows and the development of strategies for their prevention. This study reviewed case studies and outputs related to debris flow monitoring in China. The monitoring systems are set in seven catchments, with area between 2 and 40 km2, covering various types of debris flows in different climate conditions. This review also introduced the definitions and classifications adopted for debris flows in China for comparison with those used in Western literatures. A comprehensive analysis was conducted of debris flow parameters, including the grain size distribution, density, Froude number, velocity–depth relationship, volume–peak discharge relationship, volume–drainage area relationship, and velocity and peak discharge calculation methods. Additionally, the rainfall intensity–duration thresholds were compared. Accurate identification of such information is fundamental for enhancing comprehension of debris flow characteristics, facilitating monitoring, and the implementation of early warning and alarm systems. [ABSTRACT FROM AUTHOR]

Urate nephropathy, a common complication of hyperuricemia, has garnered increasing attention worldwide. However, the exact pathogenesis of this condition remains unclear. Currently, inflammation is widely accepted as the key factor in urate nephropathy. Therefore, the aim of this study was to elucidate the interaction of lincRNA-p21/AIF-1/CMPK2/NLRP3 via exosomes in urate nephropathy. This study evaluated the effect of lincRNA-p21/AIF-1/CMPK2/NLRP3 using clinical data collected from patients with urate nephropathy and human renal tubular epithelial cells (HK2) cultured with different concentrations of urate. In clinical research section, the level of lincRNA-p21/AIF-1 in exosomes of urine in patients with hyperuricemia or urate nephropathy was found to be increased, particularly in patients with urate nephropathy. In vitro study section, the level of exosomes, inflammation, autophagy, and apoptosis was increased in HK2 cells induced by urate. Additionally, the expression of lincRNA-p21, AIF-1, CMPK2, and NLRP3 was upregulated in exosomes and HK2 cells. Furthermore, manipulating the activity of lincRNA-p21, AIF-1, CMPK2, and NLRP3 through overexpression or interference vectors regulated the level of inflammation, autophagy, and apoptosis in HK2 cells. In conclusion, the pathway of lincRNA-p21/AIF-1/CMPK2/NLRP3 contributed to inflammation, autophagy, and apoptosis of human renal tubular epithelial cell induced by urate via exosomes. Additionally, the specific exosomes in urine might serve as novel biomarkers for urate nephropathy. [ABSTRACT FROM AUTHOR]

Predatory ladybirds are key natural enemies of a diversity of crop pests. Conserving ladybirds in agroecosystems to benefit from their biocontrol potential requires to understand the ecological interactions between them and functional plants. A diversity of functional plants is known to offer resources improving ladybirds' fitness and pest control effects. Yet, there is a lack of knowledge on the relationship between a diversity of functional plants found at the field scale and the dynamic of ladybird population. In this study conducted over three consecutive years, we investigated from early May to mid-August, the weekly abundance of predatory ladybirds on 15 functional plants and peach trees (Prunus persica) in a peach orchard agroecosystem in the Beijing Province of China. Seven plant species hosted 90% of the ladybird population throughout the study period. Through them, two abundance peaks of ladybirds were observed, with Vitex negundo and Prunus persica supporting the ladybirds in the first peak, Artemisia sieversiana, Vigna unguiculata, Cosmos bipinnata, Zea mays and Helianthus annuus playing a major role in the second peak. The plant species were either at their seedling, blooming or fructification stage when hosting the ladybirds, suggesting that these lasts used the diversity of resources (prey, nectar and pollen of flowers and extra-floral nectar) offered at the agroecosystem level. The present results enrich the screening of functional plants supporting predatory ladybirds in perennial agroecosystems and emphasize the need to pay attention to the long-standing plants in the surrounding habitats. It suggests that maintaining and managing a diversity of functional plants at the field scale is needed to offer a spatial and temporal continuity of resources to ladybirds. [ABSTRACT FROM AUTHOR]

There are many influencing factors and characterization indicators of the laser shock processing (LSP) quality make it difficult to evaluate the processing quality comprehensively and economically. Furthermore, there is no systematic and comprehensive evaluation system for the LSP quality. Therefore, this article combines the coefficient of variation (CV) and Vise Kriterijumska Optimizacija I Kompromisno Resenje (VIKOR) methods to establish an evaluation model. The model was used to evaluate the strengthening quality of the FGH95 superalloy to manufacture helicopter turbine disks after the LSP orthogonal test. The results show that when the laser energy is 8 J, the beam diameter is 5 mm and the number of impacts is 2, the compromise decision indicator value is 0.1806, with the relatively best strengthening effect for the FGH95 superalloy. Under the index weight set in this paper, the comprehensive material properties of the FGH95 superalloy is improved by 3.25 times compared with the unimpacted sample. The CV-VIKOR method has good stability and reliability, enabling efficient, comprehensive, and scientific evaluation and comparison of enhanced quality of different processed samples. This method has an essential reference and guiding significance for reducing the experimental workload, saving experimental costs, and promoting and applying the LSP technology. [ABSTRACT FROM AUTHOR]

Among today's nonvolatile memories, ferroelectric-based capacitors, tunnel junctions and field-effect transistors (FET) are already industrially integrated and/or intensively investigated to improve their performances. Concurrently, because of the tremendous development of artificial intelligence and big-data issues, there is an urgent need to realize high-density crossbar arrays, a prerequisite for the future of memories and emerging computing algorithms. Here, a two-terminal ferroelectric fin diode (FFD) in which a ferroelectric capacitor and a fin-like semiconductor channel are combined to share both top and bottom electrodes is designed. Such a device not only shows both digital and analog memory functionalities but is also robust and universal as it works using two very different ferroelectric materials. When compared to all current nonvolatile memories, it cumulatively demonstrates an endurance up to 1010 cycles, an ON/OFF ratio of ~102, a feature size of 30 nm, an operating energy of ~20 fJ and an operation speed of 100 ns. Beyond these superior performances, the simple two-terminal structure and their self-rectifying ratio of ~ 104 permit to consider them as new electronic building blocks for designing passive crossbar arrays which are crucial for the future in-memory computing. Designing efficient high-density crossbar arrays are nowadays highly demanded for many artificial intelligence applications. Here, the authors propose a two-terminal ferroelectric fin diode non-volatile memory in which a ferroelectric capacitor and a fin-like semiconductor channel are combined to share both top and bottom electrodes with high performance and easy fabrication process [ABSTRACT FROM AUTHOR]

The organic thin-film transistor is advantageous for monolithic three-dimensional integration attributed to low temperature and facile solution processing. However, the electrical properties of solution deposited organic semiconductor channels are very sensitive to the substrate surface and processing conditions. An organic-last integration technology is developed for wafer-scale heterogeneous integration of a multi-layer organic material stack from solution onto the non-even substrate surface of a III-V micro light emitting diode plane. A via process is proposed to make the via interconnection after fabrication of the organic thin-film transistor. Low-defect uniform organic semiconductor and dielectric layers can then be formed on top to achieve high-quality interfaces. The resulting organic thin-film transistors exhibit superior performance for driving micro light emitting diode displays, in terms of milliampere driving current, and large ON/OFF current ratio approaching 1010 with excellent uniformity and reliability. Active-matrix micro light emitting diode displays are demonstrated with highest brightness of 150,000 nits and highest resolution of 254 pixels-per-inch. The electrical properties of solution deposited organic semiconductor channels are sensitive to substrate surface and processing conditions. Here, authors develop organic-last-integration technology to fabricate multilayer organic thin film transistor material stack onto micro light-emitting diode. [ABSTRACT FROM AUTHOR]

With the outbreak of the COVID-19 pandemic, artificial intelligence (AI) has been widely used in fields such as medical treatment, while the threat of artificial intelligence has also received extensive attention. However, this topic has been only limitedly explored in China. To provide a measurement tool for AI threat research in China, this study aimed to examine the validity and reliability of the Threats of Artificial Intelligence Scale (TAI) in two Chinese samples of adults (N1 = 654, N2 = 1483). Results of exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) suggested that the one-factor model of TAI as the best fitting model. Furthermore, the Chinese TAI was significantly related to Positive and Negative Affect Scale and Self-Rating Anxiety Scale, proving good criterion-related validity of the Chinese TAI. In sum, this study suggested the Chinese version of the TAI as a reliable and effective tool in assessing AI threat in the Chinese context. Limitations and future directions are discussed. [ABSTRACT FROM AUTHOR]

Faced with the requirement of carbon emission reduction in power industry, low-carbon power dispatch involving various low-carbon approaches has been recognized as one of effective ways. Concentrate on several important approaches: wind power integration and carbon reduction cooperation, it is necessary to deal with the uncertainties of wind power and carbon reduction modes for thermal power encountered in low-carbon power dispatch. For this purpose, this paper firstly presents a distributed robust optimization model synthetically considering robustness, economy, and environment. Next, wind power characterizations, scenario division and compression methods, and allocation algorithms of initial carbon emission rights are fully discussed for the convenience of model solution. Finally, empirical analysis shows that (1) the proposed model proves to be effective not only in coping with wind power uncertainties and reducing operating costs, (2) but also in dealing with the uncertainties of carbon reduction modes and reducing carbon emissions, and (3) low-carbon power dispatching strategies combining robustness, economy, and environment could be achieved through the proposed model and method, which are especially helpful to minimize interference from these two types of uncertainty more scientifically and reasonably. [ABSTRACT FROM AUTHOR]

Environmental perception is an important research direction of coal mine sustainable development. There is much dust in the underground working environment of coal mine. This study is to identify the marker (ball) in the coal mine, which provides a basic to convert the coordinate of large-scale fully mechanized mining face point cloud to the geodetic coordinate. Firstly, in the face of the phenomenon that the uneven distribution of underground point cloud is more serious, this study further has studied on the basis of complete and incomplete geometry point cloud and generated multi-density geometry point cloud for the first time. Secondly, aiming at the problem that the geometric features of underground point cloud are not obvious enough, this study has increased the weight of point cloud normal vector in the training process of network model, so that the network model is more sensitive to different geometric features. Finally, this study has used a variety of advanced deep neural networks to directly analyze point clouds to verify the proposed method. The results show that the method proposed in this study has been combined with the dynamic graph convolution neural network (DGCNN) established earlier, which can more accurately identify the ball in tens of millions of the point clouds of coal mining process. Most importantly, this work is not only of great significance to improve the production efficiency and safety in fully mechanized mining face but also lays a foundation for realizing intelligence in the mining field and avoiding the harm of dust explosion and other accidents to workers. [ABSTRACT FROM AUTHOR]

Organic photodiodes (OPDs) have shown great promise for potential applications in optical imaging, sensing, and communication due to their wide-range tunable photoelectrical properties, low-temperature facile processes, and excellent mechanical flexibility. Extensive research work has been carried out on exploring materials, device structures, physical mechanisms, and processing approaches to improve the performance of OPDs to the level of their inorganic counterparts. In addition, various system prototypes have been built based on the exhibited and attractive features of OPDs. It is vital to link the device optimal design and engineering to the system requirements and examine the existing deficiencies of OPDs towards practical applications, so this review starts from discussions on the required key performance metrics for different envisioned applications. Then the fundamentals of the OPD device structures and operation mechanisms are briefly introduced, and the latest development of OPDs for improving the key performance merits is reviewed. Finally, the trials of OPDs for various applications including wearable medical diagnostics, optical imagers, spectrometers, and light communications are reviewed, and both the promises and challenges are revealed. [ABSTRACT FROM AUTHOR]

Chiral quantum dot (in rod)-light-emitting diodes (CQLEDs) with circularly polarized electroluminescence (CPEL) have driven interest in the future display, communication, and storage industries. However, the preparation of CQLEDs is still a challenging unresolved. Herein, we fabricated CQLEDs through spin-coating evaporation of chiral CdSe/CdS quantum rods (CCCQs) colloidal solution on indium tin oxide substrate. The CCCQs were synthesized via an isotropically epitaxial growth with cholic acid as the symmetry breaking agent, which induced one-direction chiral dislocation around the c axis of their hexagonal crystal structure. The CCCQs were ranked side-by-side in right-handed chiral arrangement with helical axis perpendicular to substrate due to chiral driving force of the cholic acid arrangement. The CQLEDs exhibited a negative CPEL signal at 600 nm with a |gEL| of 2 × 10−4, which is ascribable to the selective filtration on emission arising from the circular Bragg resonance by quasi-photonic crystal structures. [ABSTRACT FROM AUTHOR]

Lateral slope deposit failure represents a major source of material for debris flow/flood formation in headwater regions. From the perspective of inducing factors, such failures are the result of combined action of hydrodynamic and gravitational forces. This work investigated the failure process of a lateral slope soil deposit using indoor flume experiments. The key factors considered were the fine particle content and bulk density of the soil deposit, inflow discharge, and channel slope. Overall, the failure process can be divided into three stages: slope toe erosion stage, frequent failure stage, and gradual stabilization stage. Results revealed that greater bulk density and more fine particle content decreased entrainment and that slope angle has a positive effect on entrainment of the soil body. Debris floods, which occurred only when the fine particle content of the soil deposit was < 30% and only when the channel slope was > 7°, formed more easily when the bulk density of the deposit was < 1.5 or > 1.8 g/cm3. Following analysis of the factors influencing soil body entrainment, an experimental-based critical runoff condition was proposed for debris flood formation. The findings of this study enhance understanding of the mechanism of debris flood formation, which could help improve debris flood forecasting in headwater regions of mountainous catchments. [ABSTRACT FROM AUTHOR]

Nanosheet-liked mesoporous SAPO-34 zeolites were synthesized by a facile surfactant-assisted hydrothermal synthesis method. Compositions, morphology, acidities, chemical environment and texture properties of SAPO-34 zeolites synthesized were characterized by XRD, SEM, TEM, AFM, NH3-TPD, N2 adsorption–desorption, XPS, and TG measurements. The morphology and the surface acid density of SAPO-34 zeolite can be controlled by adding of cetyltrimethylammonium bromide (CTAB) and using triethanolamine (TEA) as the template. The nanosheet-liked mesoporous SAPO-34 zeolites have lower amount of strong acid strongth with the thickness of about 3.0 nm. The catalysis performance for methanol-to-olefin (MTO) over nanosheet-like SAPO-34 zeolites was systematically studied. Under the condition of temperature at 400 °C, feeding WHSV of 2.0 h−1, catalyst mass of 0.2 g and at atmospheric pressure, the methanol conversion is nearly 100% and the light olefins selectivity is 97.35%. As nanosheet-like SAPO-34 zeolites shorten the diffusion path and enhance the mass flow to and away from the catalytic centers, the catalyst lifetime is more than 420 min. [ABSTRACT FROM AUTHOR]

Developing organic field-effect transistor (OFET) biosensors for customizable detection of biomarkers for many diseases would provide a low-cost and convenient tool for both biological studies and clinical diagnosis. In this work, design principles of the OFET transducer for biosensors were derived to relate the signal-to-noise ratio (SNR) to the device-performance parameters. Steep subthreshold swing (SS), proper threshold voltage (Vth), good-enough bias-stress stability, and mechanical durability are shown to be the key prerequisites for realizing OFET bio-sensors of high transconductance efficiency (gm/ID) for large SNR. Combining a low trap-density channel and a high-k/low-k gate dielectric layer, low-temperature (<100 °C) solution-processed flexible OFETs can meet the performance requirements to maximize the gm/ID. An extended gate-structure OFET biosensor was further implemented for label-free detection of miR-21, achieving a detection limit below 10 pM with high selectivity at a low operation voltage (<1 V). [ABSTRACT FROM AUTHOR]

Banker plants increase biological pest control by supporting populations of non-pest arthropod species, used as alternative hosts or prey by natural enemies. Due to the specificity of trophic interactions, banker plants may not efficiently promote natural enemies with different ecologies. Yet in most cropping systems, different pest species are present together and require different biocontrol agents to efficiently control them. In the present study, we tested the combined use of two banker plants and their associated prey/host to enhance populations of the specialist parasitoid Encarsia formosa targeting the main tomato pest Bemisia tabaci, and a polyphagous ladybird Propylea japonica targeting the secondary pest Myzus persicae in tomato crops. In a laboratory and a greenhouse experiment, we measured the abundances of these four species using the Ricinus communis—Trialeurodes ricini banker plant system alone, in combination with the Glycines max—Megoura japonica system, or in absence of banker plants. We found that the first banker plant system enhanced populations of E. formosa, resulting in increased suppression of B. tabaci populations and the suppression of their outbreak in both our laboratory and greenhouse experiment. Conversely, abundances of P. japonica were not affected by this first system, but were significantly increased when the second was present. This resulted in increased control of M. persicae populations and the suppression of their early and late outbreaks. Our study demonstrates the potential for combined banker plants to provide long-term, sustainable control of multiple pests by their target natural enemies in complex agroecosystems. [ABSTRACT FROM AUTHOR]

Turbine disk is a key bearing component in aero-engine, and its structural design directly affects the overall performance of the engine. This work presents a cascade optimization method combining topology optimization (TOP) with shape optimization to design a high-performance twin-web turbine disk. A bi-directional evolutionary structural optimization (BESO-TOP) incorporated with random sampling sensitivity analysis strategy (RSSA) was firstly established, and the meridian surface configuration of turbine disk was designed using the RSSA-BESO-TOP. Afterward, the NURBS-spline was used to fit the obtained topological boundaries of turbine disk, and the shape optimization was subsequently carried out. Result shows that fourteen constraints regarding stress, deformation, and fatigue life for the optimal twin-web turbine disk completely meet the design requirements of aero-engine turbine disk. In contrast to the reference single-web turbine disk, the overall weight of twin-web turbine disk is reduced by 21.35% and the strain energy is improved by 8.5%, indicating that the twin-web turbine disk is generally evolving toward a fully stressed structure. Ultimately, the prototype of the optimal twin-web turbine disk was printed using 3D printing, and the DIC tests were performed to compare the mechanical responses of twin-web and single-web turbine disks. [ABSTRACT FROM AUTHOR]

Cadmium-modified HZSM-5 zeolite (Cd/HZSM-5) was prepared by ultrasound-assisted impregnation and its catalytic performance for methanol to aromatics (MTA) was investigated. It was characterized by means of XRD, SEM, TEM, Py-IR, N2 adsorption/desorption, NH3-TPD and XPS. Cd species distribute in the surface of the HZSM-5 zeolite, decreasing the crystallinity and increasing the Lewis acidity strength. Under the operating reaction condition of temperature at 400 °C, pressure at 0.1 MPa and space velocity of 1.896 h−1, 1.4 wt% Cd/HZSM-5 zeolites showed good catalytic activity for MTA with the aromatic's selectivity of 71.1%. Compared with that of about 7.5% over HZSM-5, the trimethylbenzene isomers in aromatics is 86.6% and the main product is 1,2,4-trimethylbenzene with selectivity of 34.0% in all products and 86.5% in trimethylbenzene isomers over 1.4 wt% Cd/HZSM-5 zeolites. [ABSTRACT FROM AUTHOR]

Flexible electronics have suggested tremendous potential to shape human lives for more convenience and pleasure. Strenuous efforts have been devoted to developing flexible organic field-effect transistor (FOFET) technologies for rollable displays, bendable smart cards, flexible sensors and artificial skins. However, these applications are still in a nascent stage for lack of standard high-performance material stacks as well as mature manufacturing technologies. In this review, the material choice and device design for FOFET devices and circuits, as well as the demonstrated applications are summarized in detail. Moreover, the technical challenges and potential applications of FOFETs in the future are discussed. [ABSTRACT FROM AUTHOR]

Intraguild predation (IGP)–the predation of a natural enemy species upon another one sharing a prey species–is relatively frequent in both natural and agroecosystems. This may reduce pest control and the establishment of predator populations during mass release of biological control agents or in multi-predator systems due to increased mortality of predators. IGP is exacerbated in isolated and space-limited systems such as greenhouses, due to reduced food resources and movement. Therefore, adding food resources as an alternative to the main prey, such as floral resources, could reduce IGP between natural enemies in these systems. In the present study we investigated the role of supplemental floral resources to help reduce intra- and interspecific IGP involving Harmonia axyridis and Propylea japonica (Coleoptera: Coccinellidae) in laboratory conditions, and we tested its application in a greenhouse setup. We found a significant reduction in intra- and interspecific IGP in laboratory conditions when floral resources were abundant. At a greenhouse scale, abundances of both ladybird species increased when floral resources were abundant, potentially through a combination of enhanced fertility and reduced IGP. This resulted in reduced abundances of aphid pest populations on tomato crops. Our study demonstrates that companion plants in greenhouses can improve pest control in systems with multi-species biological control agent releases. [ABSTRACT FROM AUTHOR]

A method based on QuEChERS (quick, easy, cheap, effective, rugged, and safe) sample preparation coupled with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed for determining 43 pesticide residues in strawberries. The clean-up sorbents were optimized, with 50 mg PSA + 50 mg C18 + 150 mg MgSO4 showing the best performance in d-SPE. The effect of injection volume on matrix effect (ME) was investigated. The proposed method had a linear range of 0.001–0.1 mg kg−1, and determination coefficients (R2) were greater than 0.995. Recoveries of the selected pesticides were 70.1–119.6% with relative standard deviations (RSD) at three concentrations (0.01, 0.05, and 0.1 mg kg−1) lower than 20%. The limit of quantification (LOQ) of the 43 pesticides was ≤ 0.005 mg kg−1. This method was applied to 80 strawberry samples collected from 8 villages in Beijing suburbs, and 12 pesticide residues were quantitatively detected with the concentrations ranging from 0.02 to 2.5 mg kg−1. [ABSTRACT FROM AUTHOR]

Propane dehydrogenation to propene is an endothermic reaction and CO2 hydrogenation to light olefins is an exothermic reaction. Using the CO2 hydrogenation reaction to consume the hydrogen from the propane dehydrogenation reaction, which is more favorable to propylene formation. A new method for coupling propane and CO2 to propylene is presented. The V–Fe modified KIT-6 was prepared by the ultrasonic-assisted impregnation method and used for coupling reaction of propane with CO2 to propylene. Exploring the relationship between catalytic properties and physicochemical characteristics through several characterization methods. As the appropriate amounts of V and Fe species were introduced into the framework of KIT-6, V–Fe modified KIT-6 performed large specific surface area, a highly ordered mesoporous structure and highly dispersed V and Fe active sites. The catalysis performance of V–Fe modified KIT-6 zeolites for production of propylene by propane dehydrogenation, CO2 hydrogenation and coupling reaction of C3H8 with CO2 was compared. Under the conditions of C3H8/CO2/N2 = 1:4:5, total flow rate = 20 mL/min, the temperature at 580 °C, the reaction pressure at 0.1 MPa, V/Fe molar ratio = 2 and the catalyst mass of 0.2 g, the propane conversion, propylene selectivity and yield are 37.8%, 87.0% and 32.9%, respectively. [ABSTRACT FROM AUTHOR]

To determine whether sensors should transmit collected images back to the data center, an auditing protocol is desired to check these images before transmission. Since images may contain sensitive information of the environment, privacy is an essential requirement for such an auditing protocol. Moreover, since sensors are typically low-power devices and the data center has to handle a variety of sensors, this auditing protocol should be lightweight. Taking both security and efficiency into account, we propose a novel auditing protocol on images in ambient intelligence systems, called AP-AmI (i.e., Auditing Protocol in Ambient Intelligence Systems). In AP-AmI, we use the local binary pattern technique for extracting features from images and design a novel privacy-preserving Euclid distance computation algorithm for determining whether these collected images are useful. Since these two techniques are both lightweight, AP-AmI can achieve high efficiency. At the same time, since feature vectors cannot be extracted by adversaries, AP-AmI can satisfy the privacy requirement. Experimental results show AP-AmI is feasible for real-world applications. [ABSTRACT FROM AUTHOR]

Nanoscale polymer spherical and hollow structure HZSM-5 zeolites are prepared by hydrothermal and desilication–recrystallization methods. In addition, the crystallite size of two types of HZSM-5 can be easily controlled by changing H2O/Si mole ratio. The hollow structure HZSM-5 zeolite is formed, it is due to the 010 crystal plane is the most energetically favorable orientation in silicalite-1 and the Si species is first removed on this crystal plane. The properties of different morphology zeolites were characterized by means of XRD, SEM, TEM, NH3-TPD, N2 isothermal adsorption–desorption and TG, and the catalytic performance of these two types of HZSM-5 in MTA reaction was investigated in a fixed-bed differential reactor. The results showed that the multilevel pore structure and suitable acid strength and more acid density were obtained in the hollow structure HZSM-5 zeolite. Therefore, the hollow HZSM-5 zeolite exhibited that higher catalytic lifetime and selectivity of aromatics than nanoscale polymer spherical HZSM-5 zeolite in MTA reaction. Furthermore, the Al distribution on the 010 crystal plane may change slightly during the process of fabricating hollow mesoporous, which leads to higher selectivity of p-xylene over hollow HZSM-5 than nanoscale polymer spherical HZSM-5 zeolite. [ABSTRACT FROM AUTHOR]

S-doped NiFe-based particles were prepared by a solvothermal method and used to degrade methylene blue (MB) aqueous solutions with visible light in a heterogeneous Fenton reaction. The obtained solid samples were characterized by XRD, SEM, TEM, and XPS. It was found that 0.2 g L−1 NiFe2S4 can degrade 99.8% MB solution within 6 min in the presence of 5 mM H2O2 and natural pH. The recycle experiments results indicate that the NiFe2S4 catalyst possessed better stability than NiFe2O4. Furthermore, NiFe2S4 particles can be easily separated from contaminant solution by using a magnet due to their excellent ferromagnetism. COD analysis experiments indicated that the COD removal rate of NiFe2S4 is 73.1% in 30 min. A possible mechanism was proposed, and the degradation products were measured by LC-MS. [ABSTRACT FROM AUTHOR]

A channelized debris flow/flood generally originates from initial gully erosion by superficial runoff that evolves rapidly into massive erosion of the channel bed. Knowledge of the formation conditions of such events is crucial for accurate forecasting, and determination of rainfall and runoff thresholds for such hazards is a primary concern following a strong earthquake. This work proposed a framework for debris flow/flood formation at the watershed scale in two watersheds (area: 2.4 and 32.4 km2) in the Wenchuan Earthquake area (China). The critical runoff and rainfall conditions required for debris flow/flood formation were simulated and their annual variations investigated. Ultimately, the runoff conditions required for debris flow/flood formation in the two studied watersheds were calculated on an annual basis and found to increase in time. Similarly, following consideration of three different rainfall types, critical rainfall conditions were proposed that also showed an increasing tendency. The increase of rainfall and runoff conditions for debris flow/flood formation is attributable to both the recovery of vegetation and the reduction of source materials. In comparison with actual monitored flow behaviors and previously proposed rainfall thresholds, the results showed strong consistency and high forecasting efficiency. [ABSTRACT FROM AUTHOR]

To improve the dispersion of metals and to enhance the catalytic performance of SAPO-34 molecular sieves, the template-assisted method was applied to synthesize Co, Ni and Zn modified SAPO-34 molecular sieves by using palygorskite as silicon source and tetraethylammonium hydroxide as template. The metal modified SAPO-34 molecular sieves were characterized by XRD, SEM, XPS, N2-adsorption-desorption, NH3-TPD, FTIR, ICP-AES and TG. The N atoms of tetraethylammonium hydroxide exhibited the different forces to three metal ions, thus the acidity of the molecular sieves was further regulated. Compared with metal modified SAPO-34 molecular sieves prepared by impregnation, metal modified SAPO-34 molecular sieves prepared by template-assisted maintained higher surface area, bigger pore volume and better dispersion of metals. The catalytic performance of metal modified SAPO-34 molecular sieves prepared by template-assisted method in the reaction of methanol-to-olefins (MTO) was investigated in the fixed bed reactor. Under the reaction conditions that the reaction temperature was 400 °C, the reaction pressure was 0.1 MPa, the feed WHSV was 2.0 h−1 and the mass of catalyst was 0.5 g, Ni modified SAPO-34 molecular sieves exhibited great methanol conversion and high selectivity to light olefins. The selectivity of light olefins reached 95.7%. [ABSTRACT FROM AUTHOR]

Debris flows often occur in the mountainous watersheds of earthquake-affected areas, and in the Lushan earthquake area of southwestern China, they have become a significant hazard. In this study, the influencing factors and spatial distribution of debris flows were analyzed through a review of their occurrence history. Debris flows are mainly distributed in the northwestern part of the study area, which hosts the greatest density of active faults. The debris flows are generally formed by the 'progressive bulking' effect in channels, and deep incision, lateral erosion, and blockage breaking are common processes that amplify the magnitude of such debris flows. Rainfall thresholds for different types of debris flow were proposed to explain the spatial differences between debris-flow regions, and the temporal variations of those thresholds highlighted how the rainfall conditions required for the occurrence of debris flows have changed. Natural vegetation recovery, reduction in the availability of solid material, and artificial debris-flow control projects play important roles in raising the threshold of the rainfall conditions required for triggering debris flows. [ABSTRACT FROM AUTHOR]

Using ethylene glycol as solvent and PVP as structure-directing agent, CuFe2O4 nanospheres were successfully prepared by solvothermal method. The crystal structure, morphology, magnetic properties, and pore-size distribution of samples were characterized by using X-ray diffraction, scanning electron microscope, transmission electron microscope, VSM, and BET, respectively. The effects of various preparation factors on the crystal form and morphology of the obtained samples were systematically discussed. The result exhibited that the self-assembled hollow nanospheres with good crystal form and morphology are obtained under the conditions of 0.50 g PVP, 9 mmol NaAc, reaction temperature of 180 °C, and reaction time of 24 h. The catalytic activity of CuFe2O4 hollow nanospheres was evaluated by the degradation of methylene blue (MB) and the possible degradation mechanism and pathway of MB in the CuFe2O4/H2O2 photo-Fenton-like system were proposed. In addition, the properties of CuFe2O4 particles prepared by different methods were compared and analyzed. The sample synthesized by solvothermal method has a large specific surface area and excellent magnetic properties. Furthermore, the increase in the photoelectric response and the conductivity are beneficial to the improvement of catalytic performance. [ABSTRACT FROM AUTHOR]

All-solid-state potassium ion-selective electrodes (K+ ISEs) using ordered mesoporous carbon (OMC) sphere as the solid contact (SC) are fabricated in this work, which exhibit excellent K+-sensing capability including the stable Nernstian response in a wide linear range of 10−4.19–10−0.21 M, a low detection limit of 5.4 μM, short response time, and good stability. The excellent performances of the K+ ISEs are attributable to the OMC spheres with interconnected mesopore structure, uniform spherical morphology, high surface area, high conductivity, and high capacitance, which provide the highly efficient ion-to-electron transduction between the ion-selective membrane and conductive component in the electrodes. More importantly, the OMC sphere-based SC layer can be deposited in the flexible ISEs by solution processing, which thus enables the construction of ion-sensitive field-effect transistor-based handheld K+-sensing system with high sensitivity and reproducibility, demonstrating the potentials of the OMC spheres in practical ion detection devices. [ABSTRACT FROM AUTHOR]

Background: Prostate cancer (PCa) is a common malignant human tumor and one of the main causes of cancer-related deaths in men. At present, prostate-specific antigen levels are widely used to diagnose PCa in the clinic, but they are not sufficient for an accurate early diagnosis or prognosis.Methods: To identify potential molecular markers for PCa, we used real-time PCR to measure the expression levels of various microRNAs, including miR-1825, miR-484, miR-205, miR-141, and let-7b, in the serum of 72 PCa patients and 34 healthy controls.Results: miR-1825, miR-484, miR-205, miR-141, and let-7b were shown to be highly specific for PCa, suggesting that they could be used as PCa tumor screening biomarkers. miR-205 may also be used as a biomarker for indicating bone metastasis in PCa patients, miR-1825 levels may help indicate tumor-node-metastasis classification, the evaluation of treatment effects, and determining prognosis, while let-7b levels may indicate potential tumor malignancy and the hormone resistance status and could be used as a basis to adjust individual treatments for the high-risk, early diagnosis of refractory PCa.Conclusion: This study identified possible PCa tumor markers to more accurately predict the occurrence, progression, and prognosis of PCa, and which could be used in the development of tumor drug therapy. [ABSTRACT FROM AUTHOR]

The ability to forecast debris flows is important because of their frequent occurrence and potential for large-scale damage in the Wenchuan Earthquake-hit area. Accurate understanding of the characteristics of rainfall responsible for triggering debris flows is necessary for an effective early warning procedure. This study examined the general characteristics and spatiotemporal variation of rainfall events that responsible for debris flows. Analysis was performed on rainfall data extracted during 2008-2013. The results revealed that the rainfall thresholds for debris flows varied annually and showed tendency toward higher conditions required. The coefficient of variation of relevant rainfall events indicated that the characteristics of the rainstorms changed. In addition, the coefficient of deviation revealed the spatial variation of rainfall in subregions, which was attributed to differences of the local climatic conditions that control debris flow occurrence. The primary controlling rainfall indices for triggering debris flows were filtered, and the most suitable models for establishing rainfall thresholds were selected. Ultimately, the rainfall thresholds were obtained for each subregion within the study area. [ABSTRACT FROM AUTHOR]

Simulation and projection of the characteristics of heat waves over China were investigated using 12 CMIP5 global climate models and the CN05.1 observational gridded dataset. Four heat wave indices (heat wave frequency, longest heat wave duration, heat wave days, and high temperature days) were adopted in the analysis. Evaluations of the 12 CMIP5 models and their ensemble indicated that the multi-model ensemble could capture the spatiotemporal characteristics of heat wave variation over China. The inter-decadal variations of heat waves during 1961-2005 can be well simulated by multi-model ensemble. Based on model projections, the features of heat waves over China for eight different global warming targets (1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, and 5.0 °C) were explored. The results showed that the frequency and intensity of heat waves would increase more dramatically as the global mean temperature rise attained higher warming targets. Under the RCP8.5 scenario, the four China-averaged heat wave indices would increase from about 1.0 times/year, 2.5, 5.4, and 13.8 days/year to about 3.2 times/year, 14.0, 32.0, and 31.9 days/year for 1.5 and 5.0 °C warming targets, respectively. Those regions that suffer severe heat waves in the base climate would experience the heat waves with greater frequency and severity following global temperature rise. It is also noteworthy that the areas in which a greater number of severe heat waves occur displayed considerable expansion. Moreover, the model uncertainties exhibit a gradual enhancement with projected time extending from 2006 to 2099. [ABSTRACT FROM AUTHOR]

The seven-spot ladybird beetle, Coccinella septempunctata, is a major natural enemy of aphids in the field and in greenhouses in China and is part of integrated pest management (IPM). Imidacloprid, a highly efficient insecticide that not only kills aphids at lethal concentrations, but also can cause various sublethal effects in nontarget organisms. To strengthen IPM and its sustainability, it is important assessing possible side effects on natural enemies. When the effects of sublethal concentrations (LC5 and 10%LC5) of imidacloprid on C. septempunctata were evaluated, the adult longevity was shortened by 23.97 and 28.68 %, and the fecundity reduced by 52.81 and 56.09 % compared to control population. In the F generation (i.e., the progeny of the exposed individuals), the juvenile development was slower by 1.44 days and 0.66 days, and the oviposition period was shortened by 10 and 13 days, respectively. The fecundity of the F generation decreased by 17.88, 44.03 and 51.69 % when exposed to 1%LC5, 10%LC5, and LC5, respectively. The results of demographical growth estimates showed that the intrinsic rate of increase ( r ) and net reproductive rate ( R ) were lower in C. septempunctata populations that had been exposed to sublethal concentrations of imidacloprid. The results emphasize the importance of assessing side effects of low imidacloprid concentrations on such predator species, even at the transgenerational level. [ABSTRACT FROM AUTHOR]

Based on the historical and future outputs of 17 coupled model intercomparison project phase 5 (CMIP5) models, simulation of the precipitation extremes in China was evaluated under baseline climate condition compared to a gridded daily observation dataset CN05.1. The variations in precipitation extremes for eight global warming targets were also projected. The 17 individual models and the multi-model ensemble accurately reproduced the spatial distribution of precipitation extremes, although they were limited in their ability to capture the temporal characteristics. A notable dry bias existed in Southeast China, while a wet bias was present in North and Northwest China. The precipitation extremes in China were projected to be more frequent and more intense as global temperature rise reached the 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, and 5.0 °C warming targets. The projected percentage changes in the annual number of days with precipitation >50 mm (R50) and total precipitation during days in which the daily precipitation exceeds the 99th percentile (R99p) are projected to increase by 25.81 and 69.14 % relative to the baseline climate for a 1.5 °C warming target, and by 95.52 and 162.00 % for a 4.0 °C warming target, respectively. As the global mean temperature rise increased from 1.5 to 5 °C, the subregions considerably affected by the East Asian summer monsoon (e.g., Southwest China, South China, and the Yangtze-Huai River Valley) were projected to experience a more dramatic increase in extreme precipitation events, in both number of days and intensity, while North and Northwest China were projected to suffer from relatively slight increases. The model uncertainties in the projected precipitation extremes in China by 17 CMIP5 models increase as global temperature rise increases. [ABSTRACT FROM AUTHOR]

Spatiotemporal variation of velocity is important for debris flow dynamics. This paper presents a new method, the trace projection transformation, for accurate, non-contact measurement of a debris-flow surface velocity field based on a combination of dense optical flow and perspective projection transformation. The algorithm for interpreting and processing is implemented in C ++ and realized in Visual Studio 2012. The method allows quantitative analysis of flow motion through videos from various angles (camera positioned at the opposite direction of fluid motion). It yields the spatiotemporal distribution of surface velocity field at pixel level and thus provides a quantitative description of the surface processes. The trace projection transformation is superior to conventional measurement methods in that it obtains the full surface velocity field by computing the optical flow of all pixels. The result achieves a 90% accuracy of when comparing with the observed values. As a case study, the method is applied to the quantitative analysis of surface velocity field of a specific debris flow. [ABSTRACT FROM AUTHOR]

The 2008 Wenchuan earthquake greatly altered the thresholds for rainfall-triggered debris flows within the affected area. Debris flows were widely and densely distributed, and they exhibited a range of differing local rainfall thresholds. This study looked at 518 debris flow events that occurred post-earthquake in order to analyze their spatial characteristics. The duration D (in h) and the average rainfall intensity I (in mm/h) that triggered the debris flows were determined for 252 of these events in order to analyze the spatial features of rainfall thresholds. Results show that 49 % of debris flows occurred in the highest-intensity seismic zone, 58 % occurred within 10 km of active faults, and 49 % occurred in areas with humid climate. Rainfall thresholds in these three regions were persistently lower than others. Moreover, debris flows were most frequent in watersheds smaller than 5 km, and rainfall thresholds tended to decrease with a decrease in watershed size. Given the abundant loose materials available throughout the study area, 11 extreme debris flow-prone sub-regions were selected to illustrate the spatial features of rainfall thresholds in relation to local climate conditions. The lowest and highest I- D thresholds in the sub-regions examined were I = 5.94 D (2 < D < 53) and I = 21.4 D (3 < D < 50), respectively. The lowest and mean rainfall intensities needed to trigger debris flows were power-related with the local maximum 1- and 24-h rainfall. By normalizing the rainfall intensity ( I) by mean annual precipitation (MAP), the I - D thresholds were determined. Normalized results showed that the lowest and highest I - D thresholds were I = 0.0034 D (2 < D < 53) and I = 0.0090 D (3 < D < 51), respectively. Such results are useful for debris flow forecasting based on empirical rainfall thresholds and have implications for hazard and risk assessment in this region. [ABSTRACT FROM AUTHOR]

The Wenchuan earthquake has caused abundance of loose materials supplies for debris flows. Many debris flows have occurred in watersheds in area beyond 20 km, presenting characteristics differing from those in small watersheds. The debris flows yearly frequency decreases exponentially, and the average debris flow magnitude increases linearly with watershed size. The rainfall thresholds for debris flows in large watersheds were expressed as I = 14.7 D (2 h < D < 56 h), which is considerably higher than those in small watersheds as I = 4.4 D (2 h < D < 37 h). A case study is conducted in Ergou, 39.4 km in area, to illustrate the formation and development processes of debris flows in large watersheds. A debris flow develops in a large watershed only when the rainfall was high enough to trigger the wide-spread failures and erosions on slope and realize the confluence in the watershed. The debris flow was supplied by the widely distributed failures dominated by rill erosions (14 in 22 sources in this case). The intermittent supplying increased the size and duration of debris flow. While the landslide dam failures provided most amounts for debris flows (57 % of the total amount), and amplified the discharge suddenly. During these processes, the debris flow velocity and density increased as well. The similar processes were observed in other large watersheds, indicating this case is representative. [ABSTRACT FROM AUTHOR]

The Ms 8.0 Wenchuan earthquake greatly altered the threshold for rainfall-triggered debris flows in the affected areas. It is of both scientific and practical significance to determine the rainfall thresholds. This study examines one of the regions most prone to debris flows to analyze the characteristics of rainfall that caused debris flows, and to explore local rainfall thresholds. We applied the relation between rainfall intensity and duration, peak intensity and event amount, and other single factor approaches. Comparison of effectiveness and accuracy indicates that the event rainfall is the most sensitive factor for forecasting. Analysis of the annual rainfall thresholds showed that the rainfall conditions required for debris flows have increased on the continent during the past 6 years. Besides the rainfall fluctuations over the past few years, material changes were the primary reason for threshold variability. Recovery of vegetation plays an important role in reducing potential loose material that supplies volume for debris flows. Natural solidification, decrease of the potential erosion depth, and surface coarsening make it more difficult to initiate a debris flow, and ultimately increased rainfall conditions required. The change in rainfall thresholds can be predicted and verified for the entire earthquake-affected region. [ABSTRACT FROM AUTHOR]

One-step synthesis of methylmethacrylate (MMA) using heteropoly compounds (HPCs) as catalysts was demonstrated by feeding a mixture of methacrolein (MAL), air, water, nitrogen and MeOH (methanol). The HPCs with different counter-ions, such as H1.7Cs1.5Cu0.25As0.1PMo11VO40 (CsPMo11VO40), H1.7La0.7Cu0.25As0.1PMo11VO40 (LaPMo11VO40) and H1.7K1.5Cu0.25As0.1PMo11VO40 (KPMo11VO40), were studied in oxidation of MAL, esterification of methacrylic acid (MAA) and one-step synthesis of MMA from MAL, respectively. The selectivity of MAA was up to 45.7% and MMA was 44.6% with 93.3% MAL conversion over CsPMo11VO40. [ABSTRACT FROM AUTHOR]

Keggin-type heteropoly compounds (HPCs) H3.2− x Cs x Cu0.25As0.1PMo11VO40 (x, 0–2.5) were used as catalysts for coupling reaction of methylmethacrylate (MMA) from methacrolein (MAL) in this study. And the catalytic performance of the HPCs was investigated in the oxidation-esterification coupling reaction. Moreover, the HPCs were characterized by NH3-TPD, TG-pyridine-adsorption/desorption, N2-adsorption/desorption, ICP, TG-DSC, FT-IR, XRD and TPR. These reactive results have been correlated to the acidity, surface area and reducibility. With the increasing of Cs content, surface area of the HPCs increased, while the acidity and reducibility decreased. Difference of the quantity of acid sites originated from the hydration protons being substituted by Cs+. Effects of Cs+ content on the reducibility of the HPCs indicated that Cs+ changed the structural stability of V as coordinating atoms and the proportion of the different reducible states of Mo6+. [ABSTRACT FROM AUTHOR]

This work demonstrated a dry electrode for electrocardiogram (ECG) monitoring based on graphene-coated cotton fabric by screen printing process. The cotton fabric was fully covered by the graphene flakes, which makes the sheet resistance of cotton fabric reaches as low as 42.2 Ω/sq. The ECG signals obtained from the graphene-coated textile electrode show comparable performance with the Ag/AgCl electrode under both sitting, standing, and rotating conditions. The Pearson correlation coefficient between the conventional commercial electrode and the graphene-coated textile electrode is 99.47%. The graphene-coated textile electrode exhibited an excellent flexibility with an increase resistance of 4.5% after 1000 bending cycles. The graphene-coated textile electrode after bending showed good performance for ECG signal acquisition. [ABSTRACT FROM AUTHOR]