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In this study, the authors explore how to deterministically generate symmetric multi‐qubit Dicke states such as symmetric W‐states, from arbitrary initial states in a cavity quantum electrodynamics (QED) system with the aid of measurement‐based quantum feedback control. The concrete implementation procedures of the feedback strategy, which is constructed in the form of only two constant modes, are presented in detail. In addition, the feasibility of the control scheme in preparing symmetric multi‐qubit Dicke states is explicitly demonstrated by theoretical studies and numerical simulations. [ABSTRACT FROM AUTHOR]

Polarity reversal generally enhances the electric field intensity in oil-pressboard composite insulation, leading to partial discharge and even insulation flashover or breakdown of the HVDC converter transformer. In an attempt to study the transient electric field in oil at polarity reversal, the present research adopted the Kerr electro-optic effect technique to conduct real-time measurement of the oil electric fields at the polarity reversal time of 10, 60 and 120 s respectively. Dielectric interface conditions were also adopted to capture the dynamic development of interface space charges. Research results indicate that (i) negative charges, under the absorption of insulation pressboard, are more likely to accumulate at the oil-pressboard interface. As a result, the development of electric field in oil at polarity reversal demonstrates prominent polarity effect, with faster electric field attenuation under negative voltage; (ii) the development of electric field in oil shows asymmetric features under double polarity reversals. The first reversal witnesses a high magnitude of electric field in oil that is about 1.47 times of the initial capacitive electric field, whilst the second reversal sees only 85% of the initial capacitive electric field. Such asymmetric development is mainly attributed to different accumulation performances of the positive and negative charges; iii) the shorter the polarity reversal time is, the higher the oil electric field strength will be. The maximum magnitudes of the field strength after polarity reversals with different time, however, are not much different from one another. [ABSTRACT FROM PUBLISHER]

This paper presents two transitions between microstrip and stripline in Low Temperature Co-fired Ceramic technology, including a vertical transition and a coplanar transition for millimeter-wave application. These interconnects are simulated and optimized by a three-dimensional electromagnetic field simulator. Simulation results show that the return loss of microstrip to stripline vertical transition is less than −22 dB, and insertion losses are greater than 0.5 dB up to 35 GHz, and greater than 1 dB up to 40 GHz. Similarly, the return loss of the coplanar transition is less than −32 dB and insertion loss is better than 0.5 dB. LTCC test structures were fabricated and the performance of all transitions was successfully validated by scattering parameter measurements up to 40 GHz. [ABSTRACT FROM AUTHOR]

NiO/Al 2 O 3 catalyst coatings on stainless steel and aluminum substrates, CuO/ZnO/Al 2 O 3 catalyst coating on Al substrate have been prepared by cold spray technology for fuel reforming. Deposition behavior in coating formation has been studied. Microstructure and micro-region composition of the coatings are analyzed by SEM and EDX. Results show that the coating retains its original composition and majority porosity of catalyst feedstock. Smashing of the oxide feedstock particle plays an important role in coating formation. Original particle sizes and substrate materials affect bonding of the coating with substrate. Coke formation on NiO/Al 2 O 3 coating is not so serious most likely due to good heat conduction. Bonding strength of CuO/ZnO/Al 2 O 3 catalyst coating with Al mainly belongs to mechanical interlock and it seems lower than that of NiO/Al 2 O 3 catalyst. First layer on CuO/ZnO/Al 2 O 3 coating surface peels in reaction due to its fragile material nature. Conclusively, cold spray technology can be a successful method for functional catalyst coating fabrication for fuel reforming. [ABSTRACT FROM AUTHOR]

Free moving metallic particles are one of the most common defects leading to insulation failures in gas insulated substation (GIS) equipment. The present research is designed to diagnose and assess the severity levels of partial discharge (PD) initiated by free moving metallic particles on GIS insulator surface. On a well-established 252 kV GIS experiment platform, long term tests were conducted to observe the entire development process of partial discharge from its very initiation stage till eventual flashover as the applied voltage gradually boosted. Real time measurement was undertaken during the tests to capture the trend curve of partial discharge as a result of test time, scatter plot, histogram, grey-scale map, and time-frequency map of partial discharge. The experimental results indicate that 1) partial discharge provoked by free moving metallic particles in GIS goes through three severity levels, namely, minor discharge, moderate discharge, and threatening discharge; 2) as partial discharge develops, the phase distribution is widening and corresponding shape changes occur in the scatter plot, histogram, grey-scale map, and time-frequency map. It is recommended that the features of phase distribution and the corresponding spectra could be used as important criteria in diagnosing and assessing the severity levels of partial discharge initiated by free moving metallic particles on GIS insulator surface. [ABSTRACT FROM AUTHOR]

The effects of the tensor force on the ground properties of Zr isotopes are studied in the framework of the Skyrme–Hartree–Fock approach. It is found that the tensor force strongly affects the ground state energies and the geometric symmetry properties, in particular for those isotopes near N = 60 region. The effects are attributed to the fact that the tensor force enlarges the spin and pseudospin symmetry breaking and therefore results in a ∼2 MeV sub-shell gap between d 3 / 2 and s 1 / 2 single-particle levels. [ABSTRACT FROM AUTHOR]

Enrofloxacin (ENR) residues in yellow catfish (Pelteobagrus fulvidraco) often exceed the standard due to excessive use. This study explored the pharmacokinetics of ENR and its metabolite ciprofloxacin (CIP) in yellow catfish following a single dose of 10 mg/kg body weight via intramuscular injection (IM), oral gavage (PO), or a 5‐h drug bath at 10 mg/L and 25°C. High‐performance liquid chromatography‐mass spectrometry was used to determine the ENR and CIP concentrations in various tissues. The highest ENR concentration occurred with IM administration, peaking at 4.124 mg/L in the plasma, 8.359 mg/kg in the kidney, 6.272 mg/kg in the liver, and 5.192 mg/kg in the muscle. However, PO administration resulted in the longest metabolic time, with elimination half‐lives of 56.47 h in plasma, 86.43 h in the kidney, 76.25 h in the liver, and 64.75 h in muscle. Additionally, the area under the concentration–time curve values for IM, PO, and bath administration in yellow catfish plasma were 108.36, 88.96, and 22.08 mg·h/L, respectively. These results indicate the effectiveness of all three administration methods in treating bacterial diseases in yellow catfish. The selection of an appropriate administration method depends on the minimal inhibitory concentration of ENR against pathogenic bacteria. Yellow catfish subjected to PO and IM administration require longer resting periods before they can be marketed than those receiving drug bath administration. [ABSTRACT FROM AUTHOR]

Abstract: With the rapid development of high-speed railway in China, measurements and controls of subgrade settlement have attracted much attention in recent years. A novel method to measure the subgrade settlement is proposed and a device has been developed. The device mainly contains a point light source and a point-position measurement device that uses a linear CCD to detect the position change of the point light’s image. Any position change of the point light source can be measured and the settlement for one point can be obtained remotely. The multi-point settlements can be obtained by using a series of such devices. Some methods such as self-calibration of the magnification, automatic background subtractions have been adopted to enhance the stability, adaptability and accuracy of the measurement system. The device has been used in some China high-speed railway sites and it has the advantages of high accuracy, low-cost and easy installation. [Copyright &y& Elsevier]

Abstract: Kinetics of methane steam reforming for hydrogen production has been studied through experiment in a micro-channel reactor over coating catalyst. The catalyst coating prepared by cold spray on stainless steel substrate is based on a mixture of Ni–Al oxides which is normally employed in industry for methane primary steam reforming. Two kinetic laws namely parallel as well as inverse models have been derived at atmospheric pressure, and power law type kinetics have been established using non-linear least squares optimization. With the above kinetics, simulation study has been carried out to find out temperature distribution in the micro-channel over coating catalyst at two different types of boundary conditions. The results show a quite different “cold spot” character and reactants, products distribution character in the reaction channel due to its own distinct heat and mass transfer features. The kinetics and simulation study results can be applied in aid of micro-channel reactor design, and suggestion has been proposed for catalytic coating preparation and optimization. [Copyright &y& Elsevier]

Abstract: As a matter of course, designed control laws are to be acted on actual systems. However, most designed control laws are proven to be effective when performed on ideal models of the systems as opposed to the actual systems themselves. One fundamental problem is how to ensure the satisfactory performance of the designed control laws when they are performed on actual systems. Focusing on the state stabilization of quantum systems, a two-step strategy is proposed to solve this problem. A feedback strategy and the open-loop control technique of dynamical decoupling are combined therein to deal with the inevitable differences between an actual system and its model, by taking advantage of the distinct quantum characteristics: the measurement-induced-state-transfer and the tensor product structure, with the structure characterizing the coupling between a quantum system and its environment. Specifically, in the first step, a measurement-based feedback control strategy is selected according to a model of the actual system. In the second step, by identifying the differences between the actual system and the established model as decoherence noise, a specific control procedure is designed through dynamical decoupling. This procedure allows the realization of the chosen control strategy so as to deal with the differences. [Copyright &y& Elsevier]

Background: Primary sarcomatoid carcinoma (SC) and carcinosarcoma (CS) of the liver are rare tumors. Patients and Methods: From November 1999 to June 2011, clinicopathological features and outcome of 10 SC and 14 CS patients were retrospectively studied. Results: In the SC group, six patients had hepatocellular carcinoma and four had cholangiocellular carcinoma, while in the CS group, it was nine and five patients, respectively. All cases of the sarcomatous components were vimentin-positive. Pan-cytokeratin were stained in sarcomatous components of the SC group, but not in the CS group. The sarcomatous component in the SC group was negative for desmin, myoglobin, HHF35, SMA, CD68, Mac387, AAT, CD34, and S100. In the CS group, the sarcomatous components in six cases were malignant fibrous histiocytomas, six were fibrosarcomas, and two were rhabdomyosarcomas. Median survival times were 9.6 and 4.8 months for the SC and CS groups, respectively ( P = 0.483). In univariate analysis, favorable predictors of overall survival were asymptomatic, Child-Pugh class A, no distant metastasis, and radical resection. Conclusions: SC and CS were highly aggressive malignancies with similar poor survival regardless of the histological and immunohistochemical findings. Early detection through regular physical examination and treatment with radical resection may improve the outcome of those patients. [ABSTRACT FROM AUTHOR]

With 3 figures and 6 tables Abstract The relative importance of quantitative trait locus (QTL) types controlling aluminium (Al) tolerance in a recombinant inbred line population of soybean was assessed under greenhouse sand culture in 2 years. Three growth-related indicators for Al-tolerance, namely relative total plant dry weight (RTDW), relative shoot dry weight (RSDW) and relative root dry weight (RRDW) were analysed for genetic architecture. RTDW showed relatively higher correlations and shared marker regions with RSDW and RRDW. Four additive QTL, four epistatic QTL pairs and collective unmapped QTL were identified for RTDW, with respective contributions of 22.30%, 14.86% and 40.64%, in a total genetic contribution of 77.80% to phenotypic variation, while QTL × Environment contribution was relatively negligible. Similar results were found for RSDW and RRDW. Altogether, seven additive QTL, eleven epistatic QTL pairs and collective unmapped QTL were involved with Al-tolerance. Among them, one major QTL linked to marker region GMKF046-Sat_128 on B1 was shared by the three traits. The results imply that the three QTL types are all relevant and should be comprehensively utilized for the improvement of Al-tolerance in soybean. [ABSTRACT FROM AUTHOR]

High-voltage electrode protrusion is one of the major causes of insulation failure in gas-insulated substation (GIS) equipment. The present research is designed to diagnose and assess the severity levels of the partial discharge (PD )provoked by high-voltage electrode protrusion on the GIS insulator surface. With the application of boosting voltage approach, long-term tests were conducted on a well-established 252-kV GIS experiment platform to observe the entire developing process of PD from its very initiation until the eventual flashover. Real-time measurement was also undertaken during the tests to capture the trend curves and the spectra of the PD. The study results indicate that 1) PD initiated by high-voltage electrode protrusion on GIS insulator surface undergoes through three severity levels, namely, petty discharge, medium discharge, and threatening discharge, and 2) as PD exacerbates, the phase distribution keeps widening and corresponding shape changes are shown in the scatter plot, the histogram, the gray-scale map, and the time-frequency map. It is suggested that the features of phase distribution and the corresponding spectra be used as important referential criterion in diagnosing and assessing the severity levels of the PD triggered by high-voltage electrode protrusion on the GIS insulator surface. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we put forward a fundamental question concerning feedback control of quantum systems: Is measurement-based feedback control still better than open-loop control? In contrast to the classical control theory, the answer is far from obvious. This is because measurement-based feedback needs measurement to reduce the system uncertainty, whereas the measurement on a quantum system will inevitably increase the system uncertainty in turn. In fact, there is a complicated tradeoff between the uncertainty introduced and the information gained by the measurement on a quantum system. To investigate this fundamental problem, we will only focus on a typical model of coherent control mode with and without the decoherence term in the paper. By establishing some fundamental limits on the performances of both the open-loop and measurement-based feedback controls, we will demonstrate via simulation that the measurement-based feedback control of quantum systems is still superior to the open-loop control in some sense for the typical model under consideration. [Copyright &y& Elsevier]

Simulations are important for understanding complex reactions, but their interpretation is challenging owing to the large number of degrees of freedom typically involved. To address this issue, various means for relating the dynamics of a stochastic system to its structural and energetic features have been introduced. Here, we show how two leading approaches can be combined to advantage. We use the network of transitions observed in a reversible folding/unfolding simulation of a 20-residue three-stranded antiparallel β-sheet peptide (beta3s) to estimate the probabilities of committing to stable states (the native state and major nonnative states), and these then serve as the basis for an efficient statistical procedure for identifying physical variables that describe the dynamics. We find that a single coordinate that jointly characterizes the formation of the two native turns of beta3s can adequately describe the overall folding process, despite its complex nature. Additional features associated with major pathways leading from individual nonnative states are resolved; indeed, a key result is an improved understanding of the unfolded state. Connections to other methods for analyzing complex reactions are discussed. [ABSTRACT FROM AUTHOR]

Abstract: A water-soluble, 19-mer peptide fragment of serum amyloid A called MFFD is being examined as a possible treatment for atherosclerosis. As a means of administering this drug in a sustained fashion through subcutaneous implantation, a biodegradable network formulation was prepared. The formulation consisted of 1000 and 4000Da α,ω-diacrylate oligo(d,l-lactide)-b-poly(ethylene glycol)-b-oligo(d,l-lactide) (DLPEGDLDA) copolymerized with 2700 and 5000Da ω,ω,ω-triacrylate star-poly(ɛ-caprolactone-co-d,l-lactide) using UV irradiation. The influence on the network properties and degradation rate of the network on the amount and type of DLPEGDLDA copolymerized with the two different molecular weight ASCPs were examined in vitro. The networks degraded by bulk hydrolysis at a rate controlled primarily by the molecular weight of the ASCP used. Nevertheless, all the networks were completely degraded within 16 weeks. The MFFD was released in a diffusional manner at a rate influenced by the degree of swelling of the network and the molecular weight of the ASCP used; using an ASCP of a lower molecular weight for a given DLPEGDLDA resulted in a slower release rate. The degree of swelling of the networks was controlled solely by the nature of the PEG used in preparing the DLPEGDLDA, with greater swelling observed with higher PEG molecular weight and for greater amounts of PEG incorporation. The MFFD was not degraded during the photocrosslinking reaction or by potential acidic degradation products that may have accumulated within the device. This formulation provides a means of achieving a desirable release rate from a degradable, water-swellable network through selection of ASCP molecular weight and DLPEGDLDA composition. [Copyright &y& Elsevier]

Abstract: The effect of Mn2+ ions on current efficiency (CE), deposit morphology and polarization behaviour during electrodeposition of zinc from acidic sulphate solutions was investigated. In the conditions studied, Mn2+ ions had no significant effect on CE over the concentration range of 1–10gdm−3. However, a decrease in CE of more than 35% was obtained at 50gdm−3. The cathodic polarization curves and the corresponding kinetics analysis demonstrated that this decrease in CE at higher concentrations of Mn2+ ions was due to the strong depolarizing effect of MnO4 − ions and other oxidized products of manganese. Moreover, the kinetics analysis of anodic polarization suggested that the presence of Mn2+ ions catalyzed the oxygen evolution reaction. The addition of Mn2+ ions was also observed to change the surface morphology and deposit quality of the electrodeposited zinc, affecting the crystallographic orientation by significantly inhibiting the growth of (002) and (100) planes. [Copyright &y& Elsevier]

The effects of temperature and current density on cathodic current efficiency, specific energy consumption, and zinc deposit morphology during zinc electrodeposition from sulfate electrolyte in the presence of 1-butyl-3-methylimidazolium hydrogen sulfate ([BMIM]HSO4) as additive were investigated. The highest current efficiency (93.7%) and lowest specific energy consumption (2,486 kWh t−1) were achieved at 400 A m−2 and 313 K with addition of 5 mg dm−3 [BMIM]HSO4. In addition, the temperature dependence of some kinetic parameters for the zinc electrodeposition reaction was experimentally determined. Potentiodynamic polarization sweeps were carried out to obtain the expression for each parameter as a function of temperature. In the condition studied, the exchange current density depended on temperature as ln( i0) = − a/ T + b and the charge transfer coefficient was constant. Moreover, the adsorption of the additive on cathodic surface obeyed the Langmuir adsorption isotherm. The associated thermodynamic parameters indicated the adsorption to be chemical. [ABSTRACT FROM AUTHOR]

To investigate the genetic mechanism of Al-tolerance in soybean, a recombinant inbred line population (RIL) with 184 F2:7:11 lines derived from the cross of Kefeng No.1 × Nannong 1138-2 (Al-tolerant × Al-sensitive) were tested in pot experiment with sand culture medium in net room in Nanjing. Four traits, i.e. plant height, number of leaves, shoot dry weight and root dry weight at seedling stage, were evaluated and used to calculate the average membership index ( FAi) as the indicator of Al-tolerance. The composite interval mapping (CIM) under WinQTL Cartographer v. 2.5 detected five QTLs (i.e. qFAi-1, qFAi-2, qFAi-3, qFAi-4 and qFAi-5), explaining 5.20%–9.07% of the total phenotypic variation individually. While with the multiple interval mapping (MIM) of the same software, five QTLs ( qFAi-1, qFAi-5, qFAi-6, qFAi-7, and qFAi-8) explaining 5.7%–24.60% of the total phenotypic variation individually were mapped. Here qFAi-1 and qFAi-5 were detected by both CIM and MIM with the locations in a same flanking marker region, GMKF046-GMKF080 on B1 and satt278-sat_95 on L, respectively. While qFAi-2 under CIM and qFAi-6 under MIM both on D1b2 were located in neighboring regions with their confidence intervals overlapped and might be the same locus. Segregation analysis under major gene plus polygene inheritance model showed that Al-tolerance was controlled by two major genes ( h2mg = 33.05%) plus polygenes ( h2pg = 52.73%). Both QTL mapping and segregation analysis confirmed two QTLs responsible for Al-tolerance with relatively low heritability, and there might be a third QTL, confounded with the polygenes in segregation analysis. [ABSTRACT FROM AUTHOR]

Simple Summary: In recent years, much attention has been paid to developing functional meat, which contains more functional peptides to impart health benefits. Poultry meat is a good source of imidazole dipeptides (carnosine and its derivative anserine), which are active endogenous constituents and may convey versatile physiological functions to promote health conditions. Carnosine is synthesized from l-histidine and beta-alanine. Dietary addition of histidine and/or beta-alanine may elevate the carnosine content in broiler meat. The current study further investigated the interaction of l-histidine and beta-alanine supplementation on carnosine content, meat quality, and gene expression of carnosine-related enzymes in broilers, which can facilitate a better understanding of the relationship between l-histidine and beta-alanine in carnosine synthesis. The current study investigated the effect of dietary l-histidine and beta-alanine supplementation on growth performance, meat quality, carnosine content, and gene expression of carnosine-related enzymes in broilers. A two-factor design was adopted in this study. A total of 640 1-day-old male broilers were assigned to eight treatments with factorial arrangement containing four levels of l-histidine (0, 650, 1300, or 1950 mg/kg) and two levels of beta-alanine (0 or 1200 mg/kg) supplementation; 0 mg/kg histidine and/or 0 mg/kg were treated as control groups. Each treatment including eight replicates with 10 birds each and the feeding trial lasted for 42 days. Dietary supplementation with l-histidine and beta-alanine did not affect average daily gain (ADG), average daily feed intake (ADFI), and feed conversion ratio (FCR) of broilers during the grower (22–42 days) and the entire phase (1–42 days), compared with the control group (p > 0.05). The only exception was a significantly reduced ADG in the 1950 mg/kg l-histidine group in the starter period (1–21 days, p < 0.05). l-Histidine at 1950 mg/kg significantly decreased redness (a*) and yellowness (b*) values of the meat at 45 min postmortem (p < 0.05), whereas it increased b* value and pH in breast muscle at 24 h postmortem. Moreover, dietary supplementation with beta-alanine alone or combination with l-histidine significantly increased ΔpH in breast muscle (p < 0.01). Dietary l-histidine markedly increased total superoxide dismutase activity and total antioxidant capacity (T-AOC) both in breast muscle (p < 0.01) and in plasma (p < 0.01), and it decreased malondialdehyde (MDA) concentration in breast muscle (p < 0.01). Dietary addition of beta-alanine, alone or combination, significantly increased T-AOC in breast muscle (p < 0.01) and markedly decreased MDA content both in breast muscle and in plasma (p < 0.01). Addition of l-histidine and beta-alanine significantly increased muscle peptide (carnosine and anserine) content (p < 0.05) and upregulated the expression of carnosine synthase, transporter of carnosine/ l-histidine, and l-histidine decarboxylase genes (p < 0.05), with greater change occurring in the combination group of 1300 mg/kg l-histidine and 1200 mg/kg beta-alanine. Overall, dietary l-histidine and beta-alanine could improve meat quality and antioxidant capacity, enhance the carnosine and anserine content, and upregulate the gene expression of carnosine synthesis-related enzymes in broilers. [ABSTRACT FROM AUTHOR]

We demonstrate a general approach to introduce hydrophobic functional polymers into a multilayer film using the layer-by-layer (LBL) assembly method that normally works for water-soluble polyelectrolytes. To this end, two new amphiphilic diblock copolymers each containing a hydrophobic side-chain liquid crystalline polymer (SCLCP) were synthesized using atom transfer radical polymerization, followed by a modification reaction. They are poly(acrylic acid)- b-poly{6-[4-(4′-cyanophenyl)phenoxy]hexyl methacrylate} (PAA- b-PCMA) and quaternized poly(4-vinyl pyridine- b-poly{6-[4-(4-ethyloxyphenylazo)phenoxy]hexyl methacrylate} (QP4VP- b-PAMA). We show that through the use of their micelles in aqueous solutions, which have a polycation (QP4VP- b-PAMA) or a polyanion (PAA- b-PCMA) corona, the two hydrophobic SCLCPs can be LBL assembled. The characterization results indicate that the LC phases are retained in the film, and that the SCLCPs are subjected to confinement effects inside the nanodomains defined by the core regions of the micelles. This micellar route to LBL assembly of hydrophobic functional polymers is general and offers new possibilities of designing nanostructured materials. [ABSTRACT FROM AUTHOR]

We report the observation of unusual fluorescence emission from an azobenzene-containing polymer micellar solution. An amphiphilic diblock copolymer composed of the hydrophilic quaternized poly(4-vinyl pyridine) (QP4VP) and a hydrophobic liquid crystalline polymethacrylate bearing azobenzene side groups (PAzoMA) is nonfluorescent in molecularly dissolved state in N,N-dimethyl formamide (DMF) but becomes fluorescent as a result of the micellization upon addition of water, which confines azobenzene groups into the core region of micellar aggregates. Experimental results suggest that the micellization-enhanced fluorescence was caused by a slowdown, due to the confinement effect, in the rate of the trans-to-cis photoisomerization that is the main nonradiative relaxation process for excited azobenzene groups in the trans form. Furthermore, it was found that the fluorescence intensity of aqueous micellar solution is sensitive to changes in pH (reversible fluorescence variation) and to illumination (irreversible fluorescence variation). The results indicate that a subtle change in the state of polymer micellar association may alter the confining state of azobenzene groups responsible for the fluorescence emission. [ABSTRACT FROM AUTHOR]

The flexible parallel mechanism is widely utilized in precision instruments, thanks to its numerous advantages, such as high precision, frictionless operation, and seamless movements. The establishment of the motion equations for this mechanism is crucial for designing, analyzing, controlling, and simulating parallel mechanisms. While the existing inverse kinematics solution theory is comprehensive, developing a forward solution model is challenging due to the nonlinear nature of the attitude equation. To address this issue, a new method based on the transfer matrix approach is proposed in this research to calculate the forward kinematics of parallel mechanisms. The proposed method is applied to analyze the forward kinematics and workspace of both planar and spatial flexible mechanisms. Simulation calculations and experiments are conducted to verify the method's effectiveness. The results demonstrate that the error is approximately 2%, indicating the feasibility and accuracy of the calculation method. [ABSTRACT FROM AUTHOR]

• A differentiated warning rule for power transformer health status is mined. • The differentiated warning rule overcomes the defects of conventional warning method. • Three individualized characteristics of transformer properties are mined. • The association rules between dissolved gas distribution characteristics and actual defect/fault rate are found out. Accurate on-line monitoring of transformer operation status is essential to ensure the reliability of power system. The dissolved gas analysis (DGA) method, which compares the gas concentration to the pre-set threshold, is most widely used for transformer status warning. However, existing standards apply either single threshold value or rough classification to diversified transformers with different properties, which therefore affects the accuracy of status warning. This paper establishes a differentiated warning rule through big data analysis mining. The Fuzzy C -means method is applied to identify optimal transformer properties, which can reflect the individualized characteristics of transformer to the best extent. As verified by the probability plot, the full sets of dissolved gas data under the selected properties conform to the Weibull Model. Association analysis is then carried out between the dissolved gas distribution characteristics and defect/ fault rate, and the warning thresholds are accordingly calculated. Correlating the gas concentration and gas increase rates with established warning values, the transformer operation status can be identified. The verification test indicates that the differentiated warning rule shows better performance than conventional methods and demonstrates an accuracy as high as 98.21%. [ABSTRACT FROM AUTHOR]

The adaptive coupling of the laser beam from space to single-mode fiber plays an important role in free space optical communication. A typical adaptive algorithm is stochastic parallel gradient descent algorithm (SPGD), which measures the performance index value to estimate the gradient value to maximize the coupling efficiency. It is conceivable that the presence of performance index measurement noise will have a great influence on the convergence performance of the algorithm. We propose an improved Kalman stochastic parallel gradient descent algorithm (KSPGD). Specifically, considering the influence of measurement noise on gradient estimation, we introduce the gradient prediction model in the iterative optimization process and then use the Kalman filter to estimate the gradient of the current iteration point. Kalman filter algorithm and optimization algorithm are integrated together. Simulation and experimental results show that the KSPGD algorithm can better restrain the influence of measurement noise on the convergence performance of the algorithm than the SPGD algorithm. [ABSTRACT FROM AUTHOR]

A swirling drill bit designed with an integrated vane swirler was developed to improve reverse circulation in down-the-hole hammer drilling. Its entrainment effect and influential factors were investigated by CFD simulation and experimental tests. The numerical results exhibit reasonable agreement with the experimental data, with a maximum error of 13.68%. In addition, the structural parameters of the swirler were shown to have an important effect on the reverse circulation performance of the drill bit, including the helical angle and number of spiral blades, swirler outlet area, and the flushing nozzles. The optimal parameters for the swirling drill bit without flushing nozzles include a helical angle of 60°, four spiral blades, and the area ratio of 2, while it is about 30°, 3, and 3 for the drill bit with flushing nozzles. Moreover, the entrainment ratio of the drill bit without flushing nozzles can be improved by nearly two times compared with one with flushing nozzles under the same conditions. [ABSTRACT FROM AUTHOR]

The activation of coagulation, inflammation and other pathways is the basic response of the host to infection in sepsis, but this response also causes damage to the host. Brain-derived extracellular vesicles (BDEVs) have been reported to cause a hypercoagulable state that can rapidly develop into consumptive coagulopathy, which is consistent with the pathophysiological process of sepsis-induced coagulopathy. However, the role of BDEVs in sepsis-induced coagulopathy remains unclear. Male Sprague-Dawley (SD) rats were used for sepsis modeling using cecal ligation puncture (CLP). Flow cytometry was used to measure the levels of circulating BDEVs. Enzyme-linked immunosorbent assay (ELISA) was used to measure the serum levels of plasminogen activator inhibitor type 1 (PAI-1), thrombin-antithrombin (TAT), D-dimer, fibrinogen(Fib), tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1β and IL-6. Nanoparticle tracking analysis (NTA) and Transmission electron microscopy (TEM) were used to identify BDEVs. Western blot (WB) was used to determine the expression of glial fibrillary acidic protein (GFAP), neuron-specific enolase (NSE), bax, bcl-2 and cleaved caspase-3. Hematoxylin-eosin (HE) and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining were performed to detect tissue injury. Survival was monitored over the course of 168 h. We found that a large number of BDEVs were released into the circulating blood in septic rats. Moreover, we observed that BDEVs injection activated the systemic coagulation reaction and induced lung, liver and kidney inflammation and apoptosis(P <.05). Compared with BDEVs from sham-operated rats, BDEVs from septic rats exacerbated this process(P <.05). This finding suggests that inhibiting BDEVs may yield therapeutic benefits in the treatment of sepsis-induced coagulopathy. • Brain-derived extracellular vesicles were released into blood in septic rats. • Brain-derived extracellular vesicles induced coagulopathy and tissue damage. • Brain-derived microvesicles from septic rats aggravated coagulopathy and organ injury. [ABSTRACT FROM AUTHOR]

• A high precision interface charge measuring platform under AC/DC voltages are set up. • The interface charge accumulating mechanism of oil-pressboard are presented. • The impacting mechanism interface charge on flashover features are proposed. • The conclusions could provide guidance for insulation design of oil-pressboard. The interface charges of oil-pressboard insulation could distort the local electric field and even weaken the insulating strength of converter transformer. This paper employs the electrostatic capacitive probe to capture the accumulation characteristics of interface charges in oil-pressboard insulation with needle-plate electrode under AC, DC and combined AC/DC voltages. The research results indicate that, under AC voltage, the polarity of interface charge is the same to that of the instantaneous value of applied voltage, and density of interface charge remains constant with the AC voltage application prolonging. In the context of DC voltage, the density of negative interface charge is about 1.2–1.5 times of that of the positive one. Under AC/DC combined voltage, the time-dependent dynamic accumulating process of interface charge behaves similarly to the waveform of AC voltage, and the larger the amplitude of DC component in combined voltage, the weaker the fluctuation. The tests for the surface flashover of oil-pressboard insulation were also conducted, aiming at discovering the impacting mechanism of interface charge accumulation on flashover voltage. The surface flashover voltage of test model under negative DC superimposed AC voltage is 1.3 times higher than that of positive DC combined with AC voltage. The built interface polarization model made an explanation for the interface charge accumulation, and the impacting mechanism of interface charge on flashover voltage, namely the positive effect of homopolar interface charges, is also proposed. [ABSTRACT FROM AUTHOR]

Background: Histone deacetylases (HDACs) have been demonstrated to be aberrantly activated in tumorigenesis and cancer development. Thus, HDAC inhibitors (HDACIs) are considered to be promising anti‐cancer therapeutics. However, recent studies have shown that HDACIs promote the migration of many cancer cells. Therefore, there is a need to elucidate the underlying mechanisms of HDACIs on cancer cell migration to establish a combination therapy that overcomes HDACI‐induced cell migration. Methods: KYSE‐150 and EC9706 cells were treated differently. Effects of drugs and siRNA treatment on tumor cell migration and cell signaling pathways were investigated by transwell migration assy. Gene expression for SNAI2 was tested by RT‐qPCR. Western blot analysis was employed to detect the level of E‐cadherin, β‐catenin, vimentin,Slug，ERK1/2, H3, PAI‐1 and BRD4. The effect of drugs on cell morphology was evaluated through phase‐contrast microscopic images. Results: TSA promotes epithelial‐mesenchymal transition (EMT) in ESCC cells by downregulating the epithelial marker E‐cadherin and upregulating mesenchymal markers β‐catenin, vimentin, Slug, and PAI‐1. Knockdown of Slug by siRNA or inhibition of PAI‐1 clearly suppressed TSA‐induced ESCC cell migration and resulted in the reversal of TSA‐triggered E‐cadherin, β‐catenin, and vimentin expression. However, no crosstalk between Slug and PAI‐1 was observed in TSA‐treated ESCC cells. Blocking ERK1/2 activation also inhibited TSA‐induced ESCC cell migration, EMT, and upregulation of Slug and PAI‐1 levels in ESCC cells. Interestingly, inhibition of BRD4 suppressed TSA‐induced ESCC cell migration and attenuated TSA‐induced ERK1/2 activation and upregulation of Slug and PAI‐1 levels. Conclusions: Our data indicate the existence of at least two separable ERK1/2‐dependent signaling pathways in TSA‐mediated ESCC cell migration: an ERK1/2–Slug branch and an ERK1/2‐PAI‐1 branch. Both branches of TSA‐induced ESCC cell migration appear to favor the EMT process, while BRD4 is responsible for two separable ERK1/2‐dependent signaling pathways in TSA‐mediated ESCC cell migration. [ABSTRACT FROM AUTHOR]

A simple one-dimensional theory is presented to assess the implantation of ions from the ion matrix sheath (IMS) in an ablated plasma plume that is approaching a negatively biased substrate. Under the assumption that the plume geometry, the electron and ion density distributions, and the potential distribution are frozen during the IMS extraction, the implanted ion current is calculated as a function of time for various substrate-plume separations. This model accurately recovers Lieberman's classic results when the plume front is initially in contact with the substrate. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

C10H9Cl2NO4, orthorhombic, Pbca, a = 11.151(2) Å, b = 7.0923(14) Å, c = 29.243(6) Å, V = 2312.7(8) Å3, Z = 8, Rgt(F) = 0.0459, wRref(F2) = 0.1223, T = 293 K. [ABSTRACT FROM AUTHOR]

New 1,3,5-trimethylpyrazole-containing malonamide derivatives based on pyflubumide were designed, synthesized, and characterized using 1H-NMR, 13C-NMR, and high-resolution mass spectra (HRMS). The results of preliminary bioassays showed that the target compounds possessed good activities against Tetranychus cinnabarinus, Plutella xylostella, and Aphis craccivora. Most of the target compounds exhibited moderate to good acaricidal activity against Tetranychus cinnabarinus at a concentration of 400 µg/mL, and some showed moderate activity at a concentration of 200 µg/mL; in particular, compounds 8m and 8p exhibited 70.0% mortality. In addition, some of the target compounds exhibited good insecticidal activities against Plutella xylostella at a concentration of 200 µg/mL, especially compounds 8i and 8o, which achieved 100.0% mortality at a concentration of 100 µg/mL. Interestingly, some of the target compounds exhibited potent anti-aphid activity against Aphis craccivora at a concentration of 200 µg/mL; furthermore, compounds 8p and 8q demonstrated 100.0% anti-aphid activity at a concentration of 50 µg/mL. The preliminary analyses of the structure–activity relationships (SAR) indicated that the acaricidal and insecticidal activities varied significantly depending on the type of substituent and substitution pattern, which provides guidance for the further investigation of such structural modifications. [ABSTRACT FROM AUTHOR]

As a tumor-associated microRNA (miR), miR-212 has dual functions; either as an oncogene or a tumor suppressor. A high expression level of miR-212 was reported to be associated with poor outcome in patients with esophageal squamous cell carcinoma (ESCC), however, its role in ESCC progression has not been explored. In the present study, an in vitro cell model of lentivirus-mediated gain-of-function demonstrated promotion of ESCC cell migration and invasion when miR-212 was overexpressed, and no effect on cell proliferation. miR-212 resulted in downregulation of the expression of E-cadherin, β-catenin, vimentin and Twist1. Moreover, it led to increased levels of extracellular matrix (ECM)-degrading enzymes, matrix metalloproteinase-9 and urokinase-type plasminogen activator. Furthermore, berberine inhibited miR-212-induced ESCC cell migration, unlike the PI3K inhibitor LY294002, rapamycin (mTOR inhibitor), 5-(Tetradecyloxy)-2-furoic acid (TOFA; an acetyl-CoA carboxylase 1 inhibitor), metformin and propranolol. These data suggest that miR-212 activates multiple signaling cascades and facilitates ESCC cell motility and invasion by promoting the epithelial-mesenchymal transition and degrading the ECM. Berberine may be a potential therapeutic agent against metastasis in patients with ESCC, who express high levels of miR-212. [ABSTRACT FROM AUTHOR]

• Role of TSP2 in cell invasion, migration and angiogenesis is studied. • TSP2 is downregulated and the Notch signaling pathway is activated in MB tissues. • TSP2 inhibits cell invasion and migration in MB. • TSP2 restrains angiogenesis by inhibiting the Notch signaling pathway in MB. • TSP2 may be a promising therapeutic target in MB treatment. Medulloblastoma (MB) represents a fatal malignancy often occurring in children. Angiogenesis is a hallmark of the progression of MB. Over the past decade, investigators have attempted to develop more effective and less toxic anti-angiogenic strategies to treat MB. Thrombospondin (TSP) family is observed to be a key regulator of angiogenesis. Thus, the current study aimed to elucidate the function of TSP2 in patients with MB and the underlying mechanism. The expression of TSP2, Notch1 and VEGF in MB and adjacent tissues collected from clinical samples as well as a MB cell line (Daoy) was examined. The results demonstrated that in the MB tissues and Daoy cells, TSP2 was downregulated, while Notch1 and VEGF were upregulated. Then, after the Daoy cells were treated with TSP2 silencing, TSP2 overexpression, or Notch signaling pathway inhibition, a series of in vitro cell experiments were performed to verify the interaction between TSP2 and Notch signaling pathway, and to examine the abilities of cell proliferation, migration, invasion, and tube formation. Upregulation of TSP2 was observed to lead to the downregulation of the Notch signaling pathway. Moreover, cells overexpressing TSP2 exhibited diminished proliferation, invasion, migration, and tube formation. In addition, a significant attenuation of tumor growth and angiogenesis was identified in vivo in the Daoy cells overexpressing TSP2 inoculated in nude mice. Taken together, the key findings of this study revealed the inhibitory role of TSP2 in the development of MB via blockade of the Notch signaling pathway, highlighting its potential as a treatment target for MB treatment. [ABSTRACT FROM AUTHOR]

We investigate a generalized Aubry-André-Harper (AAH) model with p-wave superconducting pairing. Both the hopping amplitudes between the nearest-neighboring lattice sites and the on-site potentials in this system are modulated by a cosine function with a periodicity of 1/α. In the incommensurate case [α=(√5-1)/2], due to the modulations on the hopping amplitudes, the critical region of this quasiperiodic system is significantly reduced and the system becomes easier to be turned from extended states to localized states. In the commensurate case (α=1/2), we find that this model shows three different phases when we tune the system parameters: Su-Schrieffer-Heeger (SSH)-like trivial, SSH-like topological, and Kitaev-like topological phases. The phase diagrams and the topological quantum numbers for these phases are presented in this work. This generalized AAH model combined with superconducting pairing provides us with a useful test field for studying the phase transitions from extended states to Anderson localized states and the transitions between different topological phases. [ABSTRACT FROM AUTHOR]

Objective: Guided bone regeneration with titanium mesh is a commonly used bone augmentation technique. However, deformation and sliding may occur during the installation of titanium mesh, which may lead to poor accuracy of bone augmentation. This article presented three cases, which describe a tooth‐supported titanium mesh bending and positioning module aiming to improve the precision of bone augmentation. Clinical Considerations: After designing the ideal bone increment volume digitally, print out the difference bone module between the ideal and existing bone mass and one or two wings. The wings are supported by the adjacent teeth to show the ideal bone mass in the patients' mouth. Finally, the titanium mesh is bent and installed in the ideal position by the module. Conclusions: A favorable outcome has been preliminarily confirmed in these cases, the average vertical bone gain was 4.16 mm and the average horizontal gain was 7.48 mm after 6 months. Using the module in the treatment of patients with bone augmentation can effectively improve the accuracy, the maximum deviation was 1.5 mm and the mean was 0.6 mm. Clinical Significance: This study improves the bone augmentation technology with titanium mesh. The titanium mesh is fixed in the ideal position, which facilitates subsequent implantation and denture repair. [ABSTRACT FROM AUTHOR]

Phenanthrene (Phe), a typical polycyclic aromatic hydrocarbon (PAH) pollutant, poses an enormous safety risk to rice-crab coculture (RC) paddy ecosystems. In this study, humic acid-modified purified attapulgite (HA-ATP) with a composite structure was successfully fabricated to adsorb PAHs released from paddy soil to overlying water in RC paddy ecosystems in Northeast China. The maximum crab bioturbation intensities for dissolved Phe and particulate Phe were 64.83nullng/L·(cm2·d) and 214.29nullng/L·(cm2·d), respectively. The highest concentration of dissolved Phe released from paddy soil to overlying water due to crab bioturbation reached 80.89nullng/L, while the corresponding concentration of particulate Phe reached 267.36nullng/L. The dissolved organic carbon (DOC) and total suspended solid (TSS) concentrations in overlying water increased correspondingly and were strongly correlated with dissolved Phe and particulate Phe concentrations, respectively (P < 0.05). When 6% HA-ATP was added to the surface layer of paddy soil, the efficiency of the adsorption of Phe release was 24.00%–36.38% for particulate Phe and 89.99%–91.91% for dissolved Phe. Because HA-ATP has a large adsorption pore size (11.33 nm) and surface area (82.41nullm2/g) as well as many HA functional groups, it provided multiple hydrophobic adsorption sites for dissolved Phe, which was conducive to competitive adsorption with DOC in the overlying water. In contrast to that adsorbed by DOC, the average proportion of dissolved Phe adsorbed by HA-ATP reached 90.55%, which reduced the dissolved Phe concentration in the overlying water. Furthermore, even though the particulate Phe was resuspended by crab bioturbation, HA-ATP immobilized particulate Phe due to its capacity to inhibit desorption, which achieved the goal of reducing the Phe concentration in the overlying water. This result was confirmed by research on the adsorption-desorption characteristics of HA-ATP. This research provides an environmentally friendly in situ remediation method for reducing agricultural environmental risks and improving rice crop quality. [Display omitted] • Modified attapulgite was prepared by hot acid modification with humic acid. • Crab bioturbation disrupted the Phe distribution balance between paddy soil and overlying water. • The adsorption efficiency of released dissolved and particulate Phe reached 91.91% and 36.38%. • HA-ATP and DOC competitively adsorbed dissolved Phe in overlying water. • HA-ATP immobilized particulate Phe in overlying water during resuspension. [ABSTRACT FROM AUTHOR]

Key message: The resistance of Huaidao5 results from the high constitutive expression of tolerance genes, while that of Huaidao9 is due to the cold-induced resistance in flag leaves and panicles. The regulation mechanism of rice seedlings' cold tolerance is relatively clear, and knowledge of its underlying mechanisms at the reproductive stage is limited. We performed differential expression and co-expression network analyses to transcriptomes from panicle and flag leaf tissues of a cold-tolerant cultivar (Huaidao5), and a sensitive cultivar (Huaidao9), under reproductive-stage cold stress. The results revealed that the expression levels of genes in stress-related pathways such as MAPK signaling pathway, diterpenoid biosynthesis, glutathione metabolism, plant–pathogen interaction and plant hormone signal transduction were constitutively highly expressed in Huaidao5, especially in panicles. Moreover, the Hudaidao5's panicle sample-specific (under cold) module contained some genes related to rice yield, such as GW5L, GGC2, SG1 and CTPS1. However, the resistance of Huaidao9 was derived from the induced resistance to cold in flag leaves and panicles. In the flag leaves, the responses included a series of stress response and signal transduction, while in the panicles nitrogen metabolism was severely affected, especially 66 endosperm-specific genes. Through integrating differential expression with co-expression networks, we predicted 161 candidate genes (79 cold-responsive genes common to both cultivars and 82 cold-tolerance genes associated with differences in cold tolerance between cultivars) potentially affecting cold response/tolerance, among which 85 (52.80%) were known to be cold-related genes. Moreover, 52 (65.82%) cold-responsive genes (e.g., TIFY11C, LSK1 and LPA) could be confirmed by previous transcriptome studies and 72 (87.80%) cold-tolerance genes (e.g., APX5, OsFbox17 and OsSTA109) were located within QTLs associated with cold tolerance. This study provides an efficient strategy for further discovery of mechanisms of cold tolerance in rice. [ABSTRACT FROM AUTHOR]

Surface charges have significant impact on the evolution of surface dielectric barrier discharge (SDBD). In this work, the role of residual surface charges on repetitively nanosecond pulsed SDBD in atmospheric air is investigated using a two-dimensional fluid model, based on the assumption of preserving the distribution of surface charges at the end of the previous high voltage (HV) pulse. In the bipolar mode when the polarity of residual surface charges is opposite to that of the current HV pulse, a lower breakdown voltage and more deposited energy can be observed, showing an obvious enhancement of SDBD. In the unipolar mode, residual surface charges suppress the development of discharges and energy deposition. It is found that more residual surface charges are accumulated during the negative pulsed discharge, which have a more pronounced effect on the subsequent positive pulsed one. This is explained by the fact that the negative surface streamers directly contact the dielectric and charge it, while the positive surface streamers float above the dielectric, forming a ion-rich region near the surface. The results in this work demonstrate the mechanism of how residual surface charges affect discharge dynamics, which can be utilized to regulate energy deposition in SDBDs. [ABSTRACT FROM AUTHOR]

Z-scheme anatase/rutile TiO 2 /g-C 3 N 4 hybrids (denoted as LTARCN-x, x represents calcination temperature) were designed and synthesized by growing TiO 2 nanorods on the surface of g-C 3 N 4 utilizing impregnation-calcination method. Furthermore, through the etched effect of hydrochloric acid and calcination treatment, the as-prepared LTARCN-x possessed abundant pore structure and larger surface area, and the surface area of LTARCN-425 was 8.5 times than that of bulk g-C 3 N 4. Meanwhile, the g-C 3 N 4 would play a role of carrier to prevent from the aggregation of TiO 2 nanorods. In addition, under visible light irradiation, the Z-scheme heterostructure would be constructed between the rutile TiO 2 nanorod and g-C 3 N 4 nanosheet, respectively. The optimized photocatalyst LTARCN-425 exhibited a preferable activity, the photocatalytic hydrogen production rate of LTARCN-425 was about 1031 μmol g−1 h−1, and it was about 6.3 and 13.6 times than that of g-C 3 N 4 and TiO 2 , respectively. Moreover, the photocatalytic mechanism of the hydrogen production was studied intensively via designing fluorescent probe, Pt and PbO 2 deposition experiment, and the characterizations of EPR, TEM, HRTEM and XPS. [ABSTRACT FROM AUTHOR]

Volume resistivity of polymer dielectrics reduces significantly with the increase of temperature. As a result, in direct current (DC) power apparatus or electronic device, temperature gradient over the material can result in considerable electric field distortion which greatly threats the polymer insulation. Advanced ceramic dielectrics are promising to be alternative to polymer insulation to deal with this issue. In this paper, Al 2 O 3 and Si 3 N 4 ceramic materials with different ion doping concentrations have been manufactured. Temperature dependent resistivity characteristics of the ceramics are obtained and compared with typical polymer dielectrics. Conduction models of the ceramic dielectrics are applied to understand their temperature dependent resistivity and its modulating mechanism. Effect of ion doping on the temperature dependent resistivity has been obtained and analyzed which agrees well with their charge trapping property acquired by thermal stimulation depolarization current measurement, based on which the method to modulate the temperature stability of material resistivity have been proposed. Finally, a comprehensive comparison between ceramics and polymers in high voltage DC applications have been made which further proves the advantage of ceramic dielectrics. [ABSTRACT FROM AUTHOR]

An orthogonal experimental design method is employed to investigate the effect of the structural parameters of the drill bit used in the Casing-while-Drilling (CwD) technology on its rock cuttings carrying capacity and reverse circulation performance. The results of the range analysis indicate that diameter of inner jet nozzle has the most significant impact on the cuttings carrying capacity of the drill bit, followed by the diameter of flushing nozzle. While for the reverse circulation ability, the diameters of the flushing nozzles have a dominant impact, followed by the diameters of the inner jet nozzles. In addition, the cuttings carrying capacity and the reverse circulation effect of the drill bit can be improved by shrinking the inner jet nozzle or appropriately enlarging the flushing nozzle. Accordingly, the optimal structural parameters of the drill bit are determined. Through further experiments, the cuttings carrying efficiency and the entrainment ratio of the optimal drill bit are 99.57% and 20.36%, respectively. Moreover, the rotation speed of drill bit has a trivial effect on its performance. At any tested rotation speed, the entrainment ratio is greater than 20%, and all the rock cuttings can be carried out of the borehole bottom using the proposed drill bit with the optimal structure. To test its real performance, a large-diameter retractable drill bit with a diameter of 600 mm was manufactured and tested in field. The results demonstrated that this retractable drill bit had excellent cuttings carrying and reverse circulation ability. The average penetration rate of the drill bit reached about 1.7 m/h in the formation of weathered sandstone with argillaceous composition, which was 1.7 times greater than conventional mud drilling in the same area. [Display omitted] • A retractable drill bit was developed for using in Casing while Drilling. • The drill bit structure was optimized by orthogonal design method. • Cuttings carrying capacity and reverse circulation effect were investigated. • A drill bit with diameter of 600 mm was designed and tested in drilling field. [ABSTRACT FROM AUTHOR]

In order to study the developing process of surface discharges initiated by immobilized metallic particles attached to Gas Insulated Substation (GIS) insulators under gradually-raised applying voltages, long-term laboratory tests were conducted on a well-established 220 kV test assembly to observe the entire evaluation process of surface discharges from its inception to gradual expansion and the eventual occurrence of surface flashover. Real-time detection was conducted to record conventional impulse current (CIC) signals, UHF signals, ultrasonic signals and light emission signals from PD. Features of surface discharges at different developing stages were captured from the discharge trend curves, scatter diagrams, two-dimensional histograms, and grey-scale maps of PD. The test findings indicate that i) surface discharge initiated by immobilized metallic particles attached to GIS insulators undergoes three developing stages from corona discharge domination in the incipient stage, to co-existence of corona discharge and surface discharge in the expansion stage, and finally the surface discharge domination in the final stage; ii) the shape and phase distribution shown in scatter diagram, histogram and grey-scale map could be used as effective criteria to infer different evolutionary stages of surface discharges produced by immobilized metallic particles attached to GIS insulators. [ABSTRACT FROM AUTHOR]