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Herein, we report a nanocomposite electrocatalyst with coupled Cu and NiO, showing a high Faraday efficiency of 97% and excellent ammonia production rate (450 mg h−1 cm−2) for nitrate reduction. In situ UV-vis spectroscopic studies confirmed that the synergy between NiO and Cu could avoid NO2− enrichment and promote tandem nitrate reduction to ammonia synthesis. [ABSTRACT FROM AUTHOR]

A hybrid control strategy is proposed for a SS compensated three-phase wireless power transfer (3P-WPT) system, which realizes full zero-voltage switching (ZVS) operation of the converter during the entire charging process of a battery. First, a mathematical equivalent model of 3P-WPT is established by fundamental harmonic approximation, the ZVS operation of the active bridge in the constant current (CC) charging mode is optimized by considering the relationship between the input impedance, operation frequency, and duty cycle. Consequently, an optimal modulation strategy featuring full ZVS operation is proposed for the constant current and constant voltage (CV) charging modes of 3P-WPT. Second, based on the NSGA-II algorithm, a mathematical model for the multi-objective optimization of coils is established, which aims for a high transmission frequency and power density. The parameters of coils are optimized accordingly. Finally, a 2 kW experimental prototype is built. Experimental results verify the effectiveness of the proposed control strategy, where the maximum efficiency is up to 90.26% at a full load. [ABSTRACT FROM AUTHOR]

The present study introduces a novel algorithm based on the homotopy analysis method (HAM) to efficiently solve the equation of motion of simply supported transversely and axially loaded double-beam systems. The original HAM was developed for single partial differential equations (PDEs); the current formulation applies to systems of PDEs. The system of PDEs is derived by modeling two prismatic beams interconnected by a nonlinear inner layer as Euler–Bernoulli beams. We employ the Bubnov–Galerkin technique to turn the PDEs' system into a system of ordinary differential equations that is further solved with the HAM. The flexibility and straightforwardness of the HAM in computing time-dependent components of the system's transverse deflection and natural frequencies, in conjunction with the observed fast convergence, offer a robust semi-analytical method for analyzing such systems. Finally, the transverse deflection is built through the modal superposition principle. Thanks to a judicious and high-flexibility selection of initial guesses and convergence control parameters, numerical examples confirm that at most six iterations are needed to achieve convergence, and the results are consistent with the selected benchmark cases. [ABSTRACT FROM AUTHOR]

Two-dimensional numerical simulations based on an immersed boundary method are performed for the two-foil system with varying spacings, and a staggered arrangement with a spacing normalized by chord length (X d / D , Y d / D) = (2.0 , 2.5) is found to be the most favorable for energy harnessing with the efficiency enhancement of nearly 40% for the downstream foil. By scrutinizing the mean flow characteristics and the instantaneous wake dynamics, it is revealed that convective flow acceleration and vortex impingement in synchronized timing with foil motion are the two primary mechanisms that contribute to significant efficiency improvement. Based on the staggered arrangement for the two-foil system, a V-shape formation is further proposed for the multiple-foil system and verified with the highest efficiency of energy harnessing up to nearly twice that of a single foil. [ABSTRACT FROM AUTHOR]

Short packet communications play key roles in the Internet-of-Things. Conventional Shannon’s coding theorem is not applicable for short packet communications, and the achievable rate in the finite blocklength regime is related to the blocklength and the decoding error probability. Contrary to conventional physical layer security, wireless information surveillance assumes that the communication users are suspicious users and the eavesdroppers are legitimate monitors, and proactive eavesdropping via jamming has been proposed to improve the eavesdropping performance. Existing works on proactive eavesdropping ignored the scenario when the suspicious users adopt the short packet communications. Thus, this paper tries to develop effective proactive eavesdropping schemes suitable for the short packet suspicious communications. Under the truncated channel inversion power allocation and the modified constant power allocation policies at the suspicious source, the problems of jamming power allocation for maximizing the monitoring success probability subject to the average transmit power constraint at the monitor are investigated. Based on the Dinkelbach-type algorithm, the Lagrange duality method and a novel tractable approximate expression for the decoding error probability, we derive suboptimal solutions to the problems. Simulation results demonstrate the effectiveness of the proposed solutions compared to various benchmark algorithms in existing literature. [ABSTRACT FROM AUTHOR]

Background. Breast cancer is the frequent cause of disease burden related to cancer among women. It affects one in 20 women globally and up to one in eight women in high-income countries. Cuproptosis is a copper-induced modality of mitochondrial cell death that is involved in tumor proliferation and metastasis. Methods. To construct a prognostic cuproptosis-related signature, LASSO Cox regression analysis was employed. Additionally, ceRNA was developed with an aim of exploring the possible lncRNA-miRNA-mRNA regulatory axis in breast cancer. Results. The expression of FDX1, DLD, DLAT, LIAS, LIPT1, GLS MTF1, and PDHA1 was downregulated, while CDKN2A expression level was elevated in breast cancer in contrast with normal tissue. We furthermore reviewed the genetic mutation landscape of genes linked to cuproptosis in breast cancer. Prognosis analysis revealed poor OS and RFS rates in breast cancer patients with elevated levels of CDKN2A and PDHA1 and low levels of MTF1, DLD, LIPT1, and FDX1. We then constructed a cuproptosis-related signature with six genes (DKN2A, MTF1, PDHA1, DLD, LIPT1, and FDX1) for breast cancer, which predicted the OS rate with an accuracy that ranged from medium to high. Further analysis demonstrated a significant correlation between the cuproptosis-related prognostic signature and pTNM stage, MSI score, drug sensitivity, TMB score, and immune cell infiltration. Moreover, we identified the lncRNA XIST/miR-92b-3p/MTF1 regulatory axis for breast cancer. Conclusion. Multiomics approaches were used to create a cuproptosis-related signature with six genes (DKN2A, MTF1, PDHA1, DLD, LIPT1, and FDX1) for breast cancer. We discovered the lncRNA XIST/miR-92b-3p/MTF1 regulatory axis for breast cancer, which has not yet been investigated previously. [ABSTRACT FROM AUTHOR]

Distributed fountain coding plays an important role in rateless code research. The reliability and effectiveness of these coding schemes are increasingly challenged with the growing applications. In this paper, a novel multiple-access network with cooperative relay is presented, and a novel enhanced distributed fountain coding scheme for this network is proposed. The overall degree distributions are derived, and the asymptotic decoding performance is analyzed theoretically by employing the And-Or tree method. On this basis, a design method using joint iterative optimization algorithms is proposed to optimize the degree distributions of the sources and relays. Simulation results show that the proposed enhanced distributed fountain codes outperform the existing generalized distributed fountain codes (GDFC) and have a good performance on both lossless and lossy channels. It reveals that the proposed codes can provide unequal error protection (UEP) property for different sources by introducing the extra cooperative relay. The performance improvement is not restricted to the sources connected to the cooperative relay but applies to all sources. With the additional relay, the proposed codes are able to overcome the effects of bad channel conditions caused by terrain, obstacles, and so on, to avoid communication interruptions and improve the reliability of the network. [ABSTRACT FROM AUTHOR]

In deep-sea mining, the accurate and rapid prediction of the pressure drop in a solid–liquid two-phase pipe flow (SLPF) with different parameters including particles, pipes, and flow fields, remains an issue yet to be fully resolved. In this study, an extensive investigation of the pressure drop in a slpf is conducted using machine-learning techniques. By collecting 1290 sets of data from 13 experimental papers and performing analysis and processing, we obtain a machine-learning ensemble algorithm capable of accurately predicting the pipe-pressure drop based on random forest (RF), back propagation (BP), and polynomial regression (PR) algorithms. The performance of the ensemble algorithm surpasses that of the other three algorithms, whether applied to pure substance (PS) particles or mixed particles (MP) containing PS and equivalent particles. For PS particles, the particle concentration and particle diameter-to-pipe diameter (PTP) account for the second and third weights influencing the pressure drop. Using the computational fluid dynamics (CFD)-discrete element method (DEM), this can be attributed to the significant kinetic energy loss caused by the collisions and friction between the particles and pipe wall and the excessive gravity of the particles, which influences the pressure drop. • An efficient and accurate machine learning algorithm based on an ensemble model is proposed for predicting the pressure drop of solid-liquid two-phase pipe flow. • The predictive accuracy of the ensemble algorithm for the pipe pressure drop, which involves particles of varying sizes, densities, and shapes, is more efficiently and accurately as well. • By altering the particle size and feed concentration, collisions and friction between particles and the pipe wall, and the excessive gravitational force acting on the particles, can all influence the pressure drop. [ABSTRACT FROM AUTHOR]

In this paper, the legitimate surveillance of a suspicious mobile edge computing (MEC) network consisting of a suspicious edge server (SES) and multiple suspicious users (SUs), in the presence of a full-duplex monitor is studied. Each SU has a computation task to complete within a time deadline and can completely or partially offload the task to SES, while the monitor can either jam or assist the suspicious communications during task uploading and result downloading. With the heterogeneous offloading model adopted by the SUs, the problem of optimizing the monitor mode and transmit power to maximize the average ratio of successfully eavesdropped tasks, subject to the monitor transmit power constraint and the task completion time deadline constraint is investigated. The problem is solved via exploring the particular problem structure and adopting the sum-of-ratios optimization. Simulation results show that the proposed algorithm significantly outperforms the benchmark algorithms, especially for the SUs with partial offloading. It is also shown that the proposed algorithm is of low-complexity and achieves almost the same performance as the high-complexity optimal algorithm. Besides, compared to the SUs with binary offloading, the eavesdropping performance for the SUs with partial offloading is shown to be much better. [ABSTRACT FROM AUTHOR]

• The 2045 W laser is used for laser cladding. • This Gaussian light into a rectangular beam conversion facilitates high speed and efficient cladding. • The ball valve is crack-free and its surface hardness has been increased by 2.7 times. In this paper, the laser cladding of Ni60 + WC powder on the stainless-steel ball valves is investigated to improve the corrosion resistance and the wear resistance of industrial ball valves. A 2-kW high-power diode laser source based on beam multiplexing is used as the processing source to clad the ball valves. To make this diode laser source more reliable for laser cladding, a homogenizing optical system is designed and optimized to transform a circular beam spot output from the optical fiber to a rectangular spot with a flat-top distribution. Employing this diode laser source, the laser cladding of the stainless-steel ball valve is successfully achieved by use of the pre-set powder feeding. The hardness testing experiments are then performed on the ball valves of different diameters, followed by the evaluation of the thickness and hardness of the cladding coating. It is experimentally demonstrated that the microhardness of the ball valves is improved by 2.7 times and the cladding layer has no cracks, which proves the superior performance of the stainless-steel ball valves by use of the proposed method. [ABSTRACT FROM AUTHOR]

Background. Esophagus cancer (ESCA) is the sixth most frequent cancer in males, with 5-year overall survival of 15%–25%. RNA modifications function critically in cancer progression, and m6A regulators are associated with ESCA prognosis. This study further revealed correlations between m6A and ESCA development. Methods. Univariate Cox regression analysis and consensus clustering were applied to determine molecular subtypes. Functional pathways and gene ontology terms were enriched by gene set enrichment analysis. Protein-protein interaction (PPI) analysis on differentially expressed genes (DEGs) was conducted for hub gene screening. Public drug databases were employed to study the interactions between hub genes and small molecules. Results. Three molecular subtypes related to ESCA prognosis were determined. Based on multiple analyses among molecular subtypes, 146 DEGs were screened, and a PPT network of 15 hub genes was visualized. Finally, 8 potential small-molecule drugs (BMS-754807, gefitinib, neratinib, zuclopenthixol, puromycin, sulfasalazine, and imatinib) were identified for treating ESCA. Conclusions. This study applied a new approach to analyzing the relation between m6A and ESCA prognosis, providing a reference for exploring potential targets and drugs for ESCA treatment. [ABSTRACT FROM AUTHOR]

Two-dimensional numerical computations are carried out for two rigidly connected cylinders of unequal sizes undergoing vortex-induced vibrations (VIV) perpendicular to the free stream. Results are examined for Re = 250 and a fixed diameter ratio of d / D = 0.2. The VIV response of the system is investigated for various positions of the small cylinder, covering a fine grid of wide radial (r) and azimuthal (θ) ranges, relative to the origin of the main cylinder. It is shown that the structural dynamics and hydrodynamic forces are strongly dependent on the arrangements. Regions of VIV reduction and amplification are distinguished, and the highest and lowest oscillation amplitudes are, respectively, acquired at configurations of (r , θ) = (0.7 D , 90 °) and (r , θ) = (0.88 D , 130 °). A deeper analysis in terms of the wake topology and surface pressure is then provided for these two extreme cases, to figure out the underlying mechanisms that lead to such markedly distinct responses. For the former case, the shear layers from two cylinders intensely interact and amalgamate during the oscillation, setting off subsequent processes of shear layer reattachment and downflow that are responsible for the observed high-amplitude response, while for the latter case, the shear layers from the small cylinder are highly stretched and absent from direct interaction with that from the large cylinder, which is favorable for stabilizing the wake and maintaining the low-amplitude response. Proper orthogonal decomposition (POD) is further utilized to correlate the key features of the wake with the dominant coherent structures in the flow. [ABSTRACT FROM AUTHOR]

Recently, wireless powered cooperative cognitive radio networks (CRNs), which combine the technologies of radio frequency (RF) energy harvesting and CR, have drawn great attention. In such networks, energy cooperation between the cognitive users (CUs) and the wireless powered primary users (PUs) can be performed, where the CUs can charge the PUs wirelessly in exchange for the spectrum access. Specifically, energy cooperation and information transmission is executed in two phases, where the CUs transmit their data signals and the PUs harvest energy from these signals in the first phase, and the PUs transmit their data using the harvested energy in the second phase. In particular, we consider two multiple access schemes for the CUs, namely non-orthogonal multiple access (NOMA) and time-division multiple access (TDMA). For both NOMA and TDMA, the PU sum-rate maximization problems under the minimum CU sum-rate constraint are first simplified by exploring particular problem structure, then are transformed to convex problems, and finally are solved optimally. The PU sum-rates of the two schemes are compared theoretically as well as numerically. It is revealed that the circuit power consumption at the CUs, the required minimum CU sum-rate, and the PU energy harvesting sensitivity and saturation thresholds play key roles in the PU performance comparison of the two schemes. [ABSTRACT FROM AUTHOR]

Three-dimensional numerical computations are carried out for a cylinder undergoing controlled sinusoidal oscillation perpendicular to the free stream. The results are examined for Re = 500 and an oscillation amplitude of A / D = 0.25 , to allow comparison with the two-dimensional study by Blackburn and Henderson [J. Fluid Mech. 385, 255–286 (1999)]. The dynamic response of the flow is investigated over a wide oscillation frequency range from 0.5fo to 1.5fo, with fo being the natural shedding frequency of the fixed cylinder. As the oscillation frequency passes through fo, the ubiquitous abrupt shift in the phase of vortex shedding is again observed. On either side of this shift, the wakes exhibit Kármán mode of shedding, in the absence of the mode switch. The hypothesis for the mechanism of phase shift proposed by Blackburn and Henderson [J. Fluid Mech. 385, 255–286 (1999)] is further examined by quantitatively measuring the flux of vorticity generated on the base of the cylinder. Unlike in two-dimensional flow, where hysteresis is found to be associated with four branches, in three-dimensional flow only two longer branches K1 and K2 are identified, which bring out a remarkably simplified bifurcation structure. Dynamic mode decomposition (DMD) and its sparsity-promoting variant are used to characterize the coherent modes that govern the dynamics of the flow, as well as their corresponding frequencies. For the non-synchronized case, a multitude of DMD modes must be retained to accurately approximate the original flow, while for the synchronized case, only four DMD modes suffice to guarantee a same performance loss. In addition, the DMD modes that have the most profound impact on the hysteresis of lift and drag fluctuations are identified by DMD reconstruction. [ABSTRACT FROM AUTHOR]

In this paper, spectrum sharing incentive for legitimate wireless information surveillance at the physical layer is investigated. The concept behind this is that authorized government agencies want to eavesdrop the communication between a suspicious source-destination pair, and stimulate the help of another source-destination pair (referred to as secondary users) looking for transmission opportunities. We thus propose to let the secondary receiver act as a monitor to eavesdrop the suspicious communication and let the secondary transmitter act as a friendly jammer to improve the eavesdropping performance, such that they are granted to share the spectrum of the suspicious users, as a reward. To guarantee the eavesdropping performance, the successful eavesdropping probability is required to be larger than that with passive eavesdropping. The problems of jointly optimizing the transmit power of the secondary transmitter and the successive interference cancellation (SIC) decoding order at the secondary receiver to maximize the average secondary transmission rate and minimize the secondary transmission outage probability are investigated. Two scenarios are considered for the availability of the channel state information (CSI). The first scenario assumes perfect CSI, and the optimal strategies for the transmit power control and the SIC decoding ordering are derived. The second scenario assumes partial CSI, where the instantaneous CSI of the secondary transmission link and the statistical CSI of the links related to the suspicious communication are available, and the optimal strategies for maximizing an approximate average secondary transmission rate and minimizing an approximate secondary transmission outage probability are proposed. Extensive simulation results validate the effectiveness of the proposed strategies. [ABSTRACT FROM AUTHOR]

A series of tuneable emission phosphors Ba 2 Ca 1 -x M x (PO 4) 2 :Eu2+ (M = Mg, Sr, Mg–Sr, and Zn) was prepared using multi-cation substitution. A new mechanism of direct/indirect substitution of Eu2+ for a host containing more than one cation and a concept of "selective excitation" for a multiple luminescence centres are proposed that are of great significance for analysing the changes of spectra and for designing colour tuneable phosphors. The emission spectra show a red shift (479 → 602 nm) with colour tuning from blue to yellow in Ba 2 Ca 1- x Mg x (PO 4) 2 :Eu2+ and a blue shift (485 → 441 nm) in Ba 2 Ca 1- x Sr x (PO 4) 2 :Eu2+. For Ba 2 Ca 1- x Zn x (PO 4) 2 :Eu2+, the emission peak first turns from 494 to 442 nm and then a red shift occurs from 442 to 585 nm when excited at 355 nm, while a continuous red shift was observed under excitation of 400 nm. Three different patterns (solid solution material, mixture transition state, and new host component) of phosphors were presented when many foreign cations were introduced into the original host. The energy transfer and thermal back-transfer over the barrier were demonstrated in as-prepared samples. Warm white light-emitting diodes (LEDs) with the International Commission on Illumination (CIE) chromaticity coordinates of (0.3622 and 0.3051), a colour rendering index (Ra) of 88.7, and a correlated colour temperature (CCT) of 3947 were realised using as-prepared phosphors. The as-developed compound series has the potential for further optimisation for commercial applications in daylight LEDs and warm white LEDs. [ABSTRACT FROM AUTHOR]

Floquet stability analysis has been employed to identify modes of three-dimensional (3D) instability in the flow over a circular cylinder of diameter D above a moving wall at a gap height of G = 0.2D, beyond the onset of two-dimensional vortex shedding. Two subharmonic modes (mode C1 and mode C2) and one long-wavelength quasi-periodic mode (mode QPL) are revealed. The characteristics of these 3D modes are discussed in detail. The results of 3D direct simulations show that it is the intensively nonlinear modal interactions that lead to a chaotic final flow state at higher Reynolds numbers, rather than the interference of the shear layer caused by the no-slip moving wall. [ABSTRACT FROM AUTHOR]

This article presents a hybrid robust sequential fusion estimation (HRSFE) method for moving-target localization in mobile asynchronous wireless sensor networks (WSNs). The estimation error or inconsistency, caused by the uncertainties of sampling, communication, and sensor-node position, is considered fully and compensated by incorporating the sensor-node position with uncertainty into the state vector as well as introducing an adaptive fading factor into the cubature Kalman filter (CKF) to maintain the estimation consistency. In addition, a QR-decomposition-based square-root form of the cubature strong localization filter (SR-CSLF) is proposed to improve the accuracy and stability of the CSLF. Moreover, an HRSFE method is designed to estimate the augment state of the WSN-assisted moving-target-localization system, and the proposed estimation method combines the merits of both the SR-CSLF and SR-CKF effectively and is able to deal with the uncertainties of sampling, communication, and sensor-node position in a unified framework. Simulations and experiments of a WSN-assisted moving-target-localization system under various uncertainty settings are employed to demonstrate the effectiveness and superiorities of the proposed method. [ABSTRACT FROM AUTHOR]

The semisubmersible platform is one of the most important equipment for the exploitation of deep-sea oil and gas. And its survival and operational capacities depend on the towing and motion performances. The present work investigates the properties of different platform component designs based on their towing and motion performances under wind and waves by using an integrated computational fluid dynamics (CFD) method. The joint application of RANS and a VOF/6-DOF solver compiled in a new Fluent UDF Library is adopted for the main calculation. Numerical simulations and results demonstrate that the VOF/6-DOF solver is accurate and stable, which could achieve the same functions as the previous OpenFOAM scheme. In order to acquire a better towing performance, different shapes are suggested for the pontoon end shape, the column cross section, and the brace longitudinal section, respectively. As to the motion response, among all the three design selections, the column cross section has the greatest influence on the whole platform. The simulation results reveal that circle section increases the roll and pitch response and reduces the heave response, to which the square section is adverse. [ABSTRACT FROM AUTHOR]

The flow-induced vibrations of an infinite long flexible cable with a triangular cross section allowed to oscillate in the transverse direction are numerically investigated at a subcritical Reynolds number of 3900. The aim of the present investigation is to reveal the underlying mechanisms of galloping of a triangular cable via a highly resolved direct numerical simulation employing a high-order spectral/hp element method. Based on our previous results [Zhu et al., Phys. Fluids 31, 057101 (2019)], only one angle of attack in which one of the sides is facing the incoming flow, α = 60°, is studied in the present simulation. A tensioned beam model is employed to govern the dynamics of the triangular cable, and a tension value is selected to trigger a single wave along the cable. The numerical results show that the response amplitude of the triangular cable is significantly larger than that of a circular cable at the same conditions, i.e., the triangular cable vibration is more vigorous. Besides, the motion of the triangular cable can be divided into two independent types: the low frequency related to galloping and the high frequency related to vortex shedding. The first- and second-order turbulence statistics are also resolved to investigate the wake characteristics of a flexible body in a turbulent regime. The numerical results indicate that, as compared to the circular cable at the same conditions, more kinetic energy is transferred from the fluid to the triangular cable, which, in turn, is responsible for a lower turbulence intensity in the near wake (x/D < 10.0) of the cable. [ABSTRACT FROM AUTHOR]

Direct stability analysis based on the Floquet theory has been employed to clarify the effects of planar shear on three-dimensional instabilities in the wake of two identical circular cylinders of diameter D in tandem arrangement. The center-to-center separation (Lx) in the range of 1.2 ≤ Lx/D ≤ 2.5 was considered. The onset of the three-dimensional instabilities was calculated, and the critical Reynolds number and corresponding spanwise wavenumber varying with the separation were discussed for different shear rates. Representative configurations were chosen to illustrate different transition scenarios, with the three-dimensional instabilities studied in detail for each case. It was found that three different effects of planar shear on the three-dimensional synchronous instability originally present in the otherwise uniform flow were identified depending on the separation. A subharmonic mode referred to as mode SS was observed to develop in the wake due to the flow asymmetry caused by the planar shear. This subharmonic mode differs from the C-type mode in terms of both the spatial structure and critical spanwise wavelength. Furthermore, the mode SS instability was found to be intensified as the shear becomes stronger, and it develops more rapidly than the synchronous modes. [ABSTRACT FROM AUTHOR]

Three-dimensional flow past a symmetrically curved circular cylinder with the free stream parallel to the plane of curvature is numerically investigated by high-order spectral element method. The axial line of the cylinder is described in Cartesian coordinates as y = A [ c o s h (x ∕ A) − 1 ] with A being a catenary coefficient used to scale its span ratio. In this geometry configuration, the deformed cylinder can be divided into two half segments, respectively of the convex segment in the upstream and the concave segment in the downstream. Different span ratios are investigated with respect to A = 0. 5 ∼ 10. It is found that four wake topologies, namely of single body, bi-stable, vortex impingement and steady wakes, are successively appeared with the increase of the span ratio. By examining the flow field quantities including mean and fluctuation of velocities and pressure along the axial line, some important characteristics of axial flow dynamics are intensively revealed. Most interestingly, the generation of axial flow along the curved surface of the cylinder is strongly influenced by not only the curvature ratio but also the wake interference effects. [ABSTRACT FROM AUTHOR]

Highlights • Formulating a maximization model of expected social welfare by given a classification of smart home applications. • Representing operating process of household appliances by Markov decision process. • Dividing the optimization problem into two sub-problems in terms of users and energy supplier. • Solving the maximization model with distributed algorithms. • Simulation studies are given to show performance of the proposed algorithm. Abstract Demand side management (DSM) aims to match power demand to supply through cutting the peak and filling the valley. It is one of the most important factors in smart grid. The real-time pricing (RTP) scheme is an ideal method to adjust power balance between supply and demand. Considering the classification of smart home appliance (SHA) and the correlation of power consumption among users, a social welfare maximization model is proposed based on Markov decision process (MDP) in the research. A probabilistic transfer matrix has been introduced to characterize the elastic appliance in smart home. Several state transfer functions have been utilized to reflect the operating process of the semi-elastic appliance also. In this way, the specific characteristics of SHA can be fully embodied. In order to improve computing efficiency and protect the user's privacy, this project divides the optimization into two subproblems in terms of users and energy supplier (ES). At user side, a modified simulated annealing RTP algorithm is developed to solve the optimization problem. Also, at ES side, the dual sub-gradient method is used to solve the convex optimization problem in the paper. Finally, the simulation results validate the rationality and feasibility of the optimization model by the decentralized RTP algorithm. [ABSTRACT FROM AUTHOR]

Highlights • Fully automated and portable vapor analysis device for formaldehyde detection (first of its kind). • Based on miniaturized heart cutting 2-D gas chromatography technology. • Rapid (∼10 min) and sensitive (∼0.23 ppb) detection of formaldehyde. • Light weight: only 1.3 kg (excluding gas cartridge); Small dimensions: 27 cm x 24 cm x 12 cm. • Versatile – capable to detect other analytes (such as benzene, toluene, ethylbenzene, and xylene). • Can be used for on-site continuous environmental monitoring, as well as industries, space exploration, and battlefield. Abstract We developed an automated and highly portable device for rapid and sensitive formaldehyde detection based on heart-cutting 2-dimensional gas chromatography. In this design, the air sample was first absorbed by a preconcentrator before it is injected into the 1st-dimensional column (Rtx®-VMS). The partial elution from the 1st-dimensional column containing formaldehyde was re-injected into the 2nd-dimensional column (Rt® Q-BOND column) for further separation. The detection of formaldehyde was achieved by using a micro-helium dielectric barrier discharge photoionization detector that is able to ionize formaldehyde (ionization potential = 10.88 eV). Due to the use of many miniaturized components, the entire system has a weight of only 1.3 kg (excluding the helium cartridge) and dimensions of only 27 cm x 24 cm x 12 cm. It is capable of detecting formaldehyde down to 0.5 ppb (V/V) with a signal-to-noise ratio of 6 in only 11 min (including 6 min of sampling). Meanwhile, simultaneous separation and detection of other air pollution related toxic compounds, such as benzene, toluene, ethylbenzene, and xylene, was also demonstrated by the 1-dimensional column and a flow-through micro-photoionization detector. The device developed here should have a broad range of applications in environmental protection, industries, space exploration, and battlefield. [ABSTRACT FROM AUTHOR]

Abstract In this paper, we numerically investigate three-dimensional flow past a freely hanging stationary riser in catenary shape (referred to CR) with the angle of incoming flow direction with respect to the plane aligned with the CR ranging from α = 0 ∘ ∼ 90 ∘ at a low Reynolds number of 100. The flow dynamics are governed by the incompressible Navier-Stokes equations and a high-order spectral/ hp element method is employed for the solutions of the flow field. The numerical results present that the wake topology behind the CR is strongly influenced by the incoming flow direction. In particular, in the range of small angle of incoming flow direction (0 ∘ ≲ α ≲ 40 ∘), the wake is completely suppressed; in the medium range of 40 ∘ ≲ α ≲ 50 ∘ , vortex shedding is developed firstly at the top side of the concave part, and then gradually spread over the span towards the convex part; wake instability is developed sufficiently along the whole span when the flow incidence is over 50 ∘. The wake dynamics is further explored by examining the temporal evolution of hydro-forces and field quantities along the span and their frequency characteristics. It is revealed that the mechanism of axial flow that is varied along the span of CR can explain hydro-dynamics of the wake behavior of the CR. Highlights • The wake behind the catenary riser is categorized into different regimes depending on the inclination angle. • Some fundamental features of three dimensional wake behind a stationary catenary riser with different inclinations are presented. • Vortex shedding is developed firstly at the top side of the concave part of the CR, and then gradually spread over the span towards the convex part. [ABSTRACT FROM AUTHOR]

Three-dimensional numerical simulation for the three circular cylinders at Re = 3900 is carried out by using the large eddy simulation (LES) in this paper. The present numerical model and parameters are verified by solving single cylinder and two cylinders cases. Then, the parameters consisted of spacing ratio (L / D) and incidence angle (α) are checked in three circular cylinders array. The fluid force and near-wake behavior of the two- and three-cylinder systems are analyzed with emphasis. Under a tight arrangement, there are three flow patterns: reattachment flow pattern, large-incidence-angle flow pattern, and biased flow pattern, corresponding to cases with incidence angles of 0, 45, and 90 degrees, respectively. The Strouhal number (St) of the three cylinders is essentially overlapping at α = 0° and α = 90°, the distinctive secondary peaks can be observed at the small spacing ratio in power spectral density (PSD). The mean pressure coefficient of midstream cylinder (MC) influenced by the number of cylinders is negative in the tandem arrangement at the stagnation point, accompanied by reattachment phenomenon the upstream surface of MC with L/D = 1.5. Placing the third cylinder between the two cylinders in a tandem arrangement significantly suppresses their lift oscillations. The phase difference (φ um) between the fluctuating lift of the upstream two cylinders is highly sensitive to the incidence angle of the system. [ABSTRACT FROM AUTHOR]

Background: Gene status has become the focus of prognosis prediction. Furthermore, deep learning has frequently been implemented in medical imaging to diagnose, prognosticate, and evaluate treatment responses in patients with cancer. However, few deep learning survival (DLS) models based on mutational genes that are directly associated with patient prognosis in terms of progression-free survival (PFS) or overall survival (OS) have been reported. Additionally, DLS models have not been applied to determine IO-related prognosis based on mutational genes. Herein, we developed a deep learning method to predict the prognosis of patients with lung cancer treated with or without immunotherapy (IO). Methods: Samples from 6542 patients from different centers were subjected to genome sequencing. A DLS model based on multi-panels of somatic mutations was trained and validated to predict OS in patients treated without IO and PFS in patients treated with IO. Results: In patients treated without IO, the DLS model (low vs. high DLS) was trained using the training MSK-MET cohort (HR = 0.241 [0.213–0.273], P < 0.001) and tested in the inter-validation MSK-MET cohort (HR = 0.175 [0.148–0.206], P < 0.001). The DLS model was then validated with the OncoSG, MSK-CSC, and TCGA-LUAD cohorts (HR = 0.420 [0.272–0.649], P < 0.001; HR = 0.550 [0.424–0.714], P < 0.001; HR = 0.215 [0.159–0.291], P < 0.001, respectively). Subsequently, it was fine-tuned and retrained in patients treated with IO. The DLS model (low vs. high DLS) could predict PFS and OS in the MIND, MSKCC, and POPLAR/OAK cohorts (P < 0.001, respectively). Compared with tumor-node-metastasis staging, the COX model, tumor mutational burden, and programmed death-ligand 1 expression, the DLS model had the highest C-index in patients treated with or without IO. Conclusions: The DLS model based on mutational genes can robustly predict the prognosis of patients with lung cancer treated with or without IO. [ABSTRACT FROM AUTHOR]

• The DRD2 expression is regulated by its promoter region upstream factors or methylation status. • Cancer cell proliferation improved the upregulation of DRD2 and decreased DRD2's downregulation. • DRD2 plays a critical role in the FLNA-ERK signaling pathway. • DRD2 gene is hypomethylated in hormone-receptor-negative breast cancer or it's high-risk factor. We investigated the effect of stem cell marker dopamine receptor D2 (DRD2) on the proliferation of hormone-receptor-negative breast cancer cells. High-throughput DNA methylation sequencing on an 850 K chip was used to pre-screen breast cancer tissues with significant methylation differences. The expression of DRD2 in breast cancer and normal breast tissues, and clinical risk factors, were detected by pyrophosphoric acid validation and immunohistochemistry. In vitro and in vivo experiments verified the possible molecular signaling pathways. DRD2 promoter region was hypomethylated in hormone-receptor-negative breast cancer or with high-risk factors compared to the normal tissues. The proliferation of breast cancer cells was enhanced after DRD2 was upregulated and decreased after DRD2 was downregulated. In vivo experiments found that tumor growth and the expression of antigen KI-67 (Ki67) and the cluster of differentiation 31 (CD31) were improved by the overexpression of DRD2 and inhibited by the down expression of DRD2. In vivo and in vitro experiments demonstrated the phosphorylation of filamin A and extracellular signal-regulated kinase (FLNA-ERK) was influenced by the expression of DRD2, suggesting DRD2 plays a role in the FLNA-ERK signaling pathway. Methylation inhibitors (5-aza-2-deoxycytidine, 5-azadc) partially reversed the inhibitory effect of DRD2 down expression on cell proliferation, migration, and tumor growth in animal models, indicating that inhibition of DRD2 methylation promotes cancer development. This study demonstrated the DRD2 promoter region is hypomethylated in hormone-receptor-negative breast cancer or with high-risk factors. The methylation status of the DRD2 promoter and FLNA-ERK signaling pathway and the DRD2 expression in breast cancer treatment need to be considered. [ABSTRACT FROM AUTHOR]

Demand side management aims to match power demand to supply through cutting the peak and filling the valley, is one of the most important factors in smart grid. The real-time pricing (RTP) mechanism is an ideal method to adjust power balance between supply and demand. Its implementation has a profound impact on users’ behavior, and on operation and management of the power grid. In this research, we propose an expectation social welfare maximization model, considering the classification of the smart home appliances (SHA) and the correlation of power consumption of multi-time slots. Users can arrange their appliances more profitable and more closely to reality with the advantage of multi-time slots RTP strategy. The constraint in the model reflects the fluctuation (uncertainty) of power consumption caused by operating continuity of the SHA. By introducing probabilistic constraints, the uncertainty optimization model is transformed into a convex optimization problem. The existence and uniqueness of the optimal solution are shown, and its properties are further analyzed. Considering the convex optimization problem is separable in dual domain, this study proposes a decentralized online RTP algorithm to determine each user’s demand and energy supplier’s supply simultaneously. By utilizing Armijo line search to instead of fixed step size of the dual subgradient method, the decentralized online RTP algorithm proposed in this research can overcome the defects of slow convergence and even no convergence from the original dual subgradient method. Finally, the simulation validates the rationality and feasibility of optimization model by the decentralized online RTP algorithm. [ABSTRACT FROM AUTHOR]

The real-time pricing mechanism based on demand response is an ideal method balancing supply and demand in the smart grid system. Its implementation will have a profound impact not only on behavior of the users, but on operation and management style of the electric power suppliers. Considering the relationship between two stages of users' power demand, a periodic social welfare maximization model based on Markov chain is presented in the research. As the result of solving the maximization model, the user may get an optimal real-time pricing strategy that helps its schedule of power consumption more reasonable and practical. The presented model has considered the known and unknown cases of parameters in the state transition probability matrix. Users with type alike have been given the realtime pricing strategy, in accordance with its correlation of influence and restrict condition of consuming electricity. Users with type not alike have been distinguished by offering different electric prices. A modified simulated annealing algorithm with centralized and distributed pricing strategy has been designed according to parameters known and unknown, respectively. Finally, a simulation process has validated rationality and feasibility of the optimization model developed in the research. [ABSTRACT FROM AUTHOR]

The real-time pricing (RTP) scheme is an ideal method to adjust the power balance between supply and demand in smart grid systems. This scheme has a profound impact on users’ behavior, system operation, and overall grid management in the electricity industry. In this research, we conduct an extended discussion of a RTP optimization model and give a theoretical analysis of the existence and uniqueness of the Lagrangian multiplier. A distributed optimization method based on the alternating direction method of multipliers (ADMM) algorithm with Gaussian back substitution (GBS) is proposed in this study. On the one hand, the proposed algorithm takes abundant advantage of the separability among variables in the model. On the other hand, the proposed algorithm can not only speed up the convergence rate to enhance the efficiency of computing, but also overcome the deficiency of the distributed dual subgradient algorithm, the possibility of nonconvergence in the iteration process. In addition, we give the theoretical proof of the convergence of the proposed algorithm. Furthermore, the interdependent relationship between variables has been discussed in depth during numerical simulations in the study. Compared with the dual subgradient method, the simulation results validate that the proposed algorithm has a higher convergence speed and better implementation effect. [ABSTRACT FROM AUTHOR]

Fly ash (FA) can improve the workability and durability of concrete. However, the utilization of FA is usually limited due to its low pozzolanic activity. In this study, a fluidized bed reactor was designed to modify FA by the fluidized bed reactor–vapor deposition (FBR-VD), using NaOH solution as the activation material. We investigated the pozzolanicity of FBR-VD modified FA (MFA), and the workability of cement paste. The results were compared against traditional chemical activation method, using Ca(OH) 2 , NaOH, Na 2 SO 4 , or NaCl. The microstructures and hydration products were analyzed by scanning electron microscopy (SEM), and thermogravimetric–differential scanning calorimetry (TG-DSC). The experimental results show that FBR-VD accelerates the early-age pozzolanic reaction of FA, without affecting the workability of the paste. The 7-day and 28-day activity indices of the paste and mortar with MFA were higher than those with raw FA, while the 60-day activity index of the paste became even close to that without FA. The SEM results indicate that FBR-VD can make the activation material coat onto the surfaces of the FA particles, breaking down part of the Si–O and Al–O bonds in the FA. The remaining NaOH crystals on the FA surface also promote the growth of Ca(OH) 2 crystals during the hydration process, so the FA particles are fixed tightly to the hardened cement paste, resulting in a higher compressive strength. TG-DSC shows that the MFA has a stronger effect on consuming the Ca(OH) 2 in the paste than traditional activation materials and methods, indicating an enhanced pozzolanic activity of the FA. [ABSTRACT FROM AUTHOR]

The wake of wavy cylinder has been shown to exhibit bistability. Depending on the initial condition, the final state of the wake can either develop into steady flow (state I), or periodic shedding (state II). In this paper, we perform numerical simulations to reveal the Reynolds number effects (R e = 30 – 300) on these two wake states. With increasing Reynolds number, the steady vortical structures in state I wake sways back and forth in the spanwise direction, resulting in low-frequency fluctuations in drag forces, but not in lift. For state II, the increase in Reynolds number is associated with the emergence of another spectral peak in the lift coefficient. The secondary frequency is associated with highly three-dimensional vortical structures in the wake. For both states, the wakes transition to turbulent flows at higher Reynolds numbers, with the development of small-scale vortices. We further study the streamwise gust flows over the wavy cylinder. The time-varying inflow velocity results in a wide range of instantaneous Reynolds number spanning from the absolutely unstable flow regime to the bistable regime. Depending on the period of the inflow velocity variation, the wake perturbations grown at the absolutely unstable flow regime can be damped out in state I wake, or grow large enough to trigger the transition to state II, resulting in loss of flow control efficacy. The above analyses reveal novel flow physics of the bistable states at unexplored Reynolds numbers, and showcase the complex transition behavior between the two states in unsteady flows. The insights gained from this study improve the understanding of the wake dynamics of the wavy cylinder. • The Reynolds number effects on the bistable states in the wake of a wavy cylinder are revealed. • A novel unsteady flow which only induces variations in drag but not in lift is discovered. • Complex transition behaviors between the two wake states in streamwise gust flow is unveiled. [ABSTRACT FROM AUTHOR]

Acid-mediated domino reaction of ortho -carbonylated alkynyl-substituted arylaldehydes with phenols is described. The implement of this reaction can provide directly a variety of tetracyclic indeno[2,1- c ]chromen-7-one products in good yields. The mechanism was proposed to be a domino indanone ring formation/ortho-alkylation of phenols/dehydrated cyclization for the formation of polycyclic skeleton. In addition, several interesting dimeric products containing a pentacyclic scaffold were also afforded stereoselectively albeit in moderate yields. The present transformations feature the use of simple acid catalyst, short reaction time and good substrate scope. [ABSTRACT FROM AUTHOR]

A base-mediated domino reaction of ortho-carbonylated alkynyl-substituted arenealdehydes with indoles has been developed, and a variety of indolyl-substituted isobenzofuran derivatives can be rapidly obtained in high yields. Notably, the selective N-alkylation of indoles and 5-exo-dig cyclization of alkynes can be achieved efficiently to give N-functionalized products. This reaction involves a domino procedure for the formation of two bonds under simple conditions and has a broad substrate scope. [ABSTRACT FROM AUTHOR]

We describe herein a gold-catalyzed tandem heteroarylation/cycloisomerization reaction ofortho-alkynylbenzaldehydes with thiophenes. By this reaction, a variety of 1-(thiophen-2-yl)-1H-isochromene derivatives can be obtained in good yield. [ABSTRACT FROM AUTHOR]

This study aimed to introduce fluidized bed reactor-vapor deposition (FBR-VD) into the modification of fly ash (FA) using the activators of NaOH, Na 2 SO 4 , and NaCl. The compressive strength, non-evaporable water and the hydration degree fly ash (HDFA) were investigated. The scanning electron microscopy (SEM), and the X-ray powder diffraction (XRD) Rietveld analysis were also conducted. The results demonstrate that FBR-VD can benefit the compressive strength when the dosage rates of NaOH, Na 2 SO 4 and NaCl are 0.1%, 0.5%, and 0.5%, respectively. The non-evaporable water and HDFA also increased at certain activator dosage rates. A modification layer consisting of nanometer-scale crystals forms on the surface of the FA beads, with NaOH or Na 2 SO 4 applied. NaOH can react with FA and promote its pozzolanic activity. Na 2 SO 4 and NaCl can benefit the HDFA by remaining undissolved, to increase their concentration around FA. The enhanced HDFA is also proved by the consumption of Ca(OH) 2 . [ABSTRACT FROM AUTHOR]

Herein we describe a reaction of ortho-carbonylated alkynyl-substituted arylaldehydes with common primary amines that can provide functionalized isoindolinone and 3-hydroxylindenamine products in high yields. Depending on the substituent size of primary amines, two distinct reaction pathways were exploited selectively, that are, an initial aza-conjugate addition followed by hydrogen transfer to access isoindolinone framework and a unique oxa-conjugate addition followed by Petasis-Ferrier rearrangement to afford indenamine derivatives. In the presence of Et3N, the reaction property of small primary amines was changed, proceeding to afford 3-hydroxylindenamine derivatives efficiently. These products contain interesting substructures that exist in many natural products and bioactive molecules. The reaction features contain the use of transition-metal-free catalysts, simple operation, broad substrate scope, and product diversity. [ABSTRACT FROM AUTHOR]

The proposed Circular Electron Positron Collider (CEPC) will be primarily aimed for precision measurements of the discovered Higgs boson. Its innermost vertex detector, which will play a critical role in heavy-flavor tagging, must be constructed with fine-pitched silicon pixel sensors with low power consumption and fast readout. CMOS pixel sensor (CPS), as one of the most promising candidate technologies, has already demonstrated its excellent performance in several high energy physics experiments. Therefore it has been considered for R&D for the CEPC vertex detector. In this paper, we present the preliminary studies to improve the collected signal charge over the equivalent input capacitance ratio ( Q / C ) , which will be crucial to reduce the analog power consumption. We have performed detailed 3D device simulation and evaluated potential impacts from diode geometry, epitaxial layer properties and non-ionizing radiation damage. We have proposed a new approach to improve the treatment of the boundary conditions in simulation. Along with the TCAD simulation, we have designed the exploratory prototype utilizing the TowerJazz 0.18 μm CMOS imaging sensor process and we will verify the simulation results with future measurements. [ABSTRACT FROM AUTHOR]

Repetitive proteins are thought to have arisen through the amplification of subdomain-sized peptides. Many of these originated in a non-repetitive context as cofactors of RNA-based replication and catalysis, and required the RNA to assume their active conformation. In search of the origins of one of the most widespread repeat protein families, the tetratricopeptide repeat (TPR), we identified several potential homologs of its repeated helical hairpin in non-repetitive proteins, including the putatively ancient ribosomal protein S20 (RPS20), which only becomes structured in the context of the ribosome. We evaluated the ability of the RPS20 hairpin to form a TPR fold by amplification and obtained structures identical to natural TPRs for variants with 2-5 point mutations per repeat. The mutations were neutral in the parent organism, suggesting that they could have been sampled in the course of evolution. TPRs could thus have plausibly arisen by amplification from an ancestral helical hairpin. [ABSTRACT FROM AUTHOR]

A method for preparing multisubstitutedN-(tosylamino)pyrrole derivatives through AuCl3-catalyzed cycloisomerization of theβ-alkynyl hydrazone compounds was described. The reaction could be carried out in one pot from theβ-ketoesters to give the cyclized products in moderate to excellent yields with low catalyst loadings. [ABSTRACT FROM AUTHOR]

• Interval analysis model is applied to quantify the uncertainties in the elastic wave tomography of concrete structures. • The relationship between the measurements error and tomography uncertainty was established. • The identified uncertain boundaries provide more information to make a better assessment of the internal condition of concrete. This paper presents a non-probabilistic uncertainty quantification method for the elastic wave tomography of concrete structures. An interval analysis model is applied to establish the relationship between the measurement error and identified tomography images. Measurements of parameters such as travel time and wave amplitude are modeled as intervals described by their upper and lower boundaries. Based on the straight-ray assumption of the wave propagation path, the relationship between wave velocity and travel time measurements is described by a set of linear equations. The inversion linear equation is converted into an extended fuzzy linear equation using interval analysis. Subsequently, a simultaneous iterative reconstruction technique is applied to solve this fuzzy linear equation. In contrast to the traditional methods, the obtained tomography images are described in terms of the upper and lower boundaries. Finally, numerical simulation and experimental investigation using several plain concrete models are conducted to verify the proposed approach. [ABSTRACT FROM AUTHOR]

An unprecedented access to strained tetracyclic bridgehead alkenes by reaction of easily accessible ortho-alkynylarylaldehydes with conjugated dienes is described. The process involves a chemo- and stereo-selective, gold-catalyzed, tandem intermolecular [3+2] cycloaddition/Prins-type ring-closing reaction that allows generating structural complexity in a straightforward manner. This approach for the preparation of anti-Bredt compounds is synthetically superior to those previously reported: the procedure is easy to implement, operates under mild experimental conditions, is efficient, and exhibits a good substrate scope. [ABSTRACT FROM AUTHOR]

An asynchronous projection and summation circuit is proposed for single photon avalanche diode (SPAD) sensors. Thanks to the efficient interconnection by the asynchronous technique, the circuit can be easily implemented inside 2D SPAD arrays. As a result, the precise summation of the 1b data in one row can be parallel processed for all rows within the same cycle. A test-of-concept chip was fabricated in a 0.18m 1P5M CMOS process. By measurement results, the summation of a 15-pixel row can be achieved by the proposed circuit within 20.5ns. Such a speed is very important for SPAD-based sensors that need fast summation operations. [ABSTRACT FROM AUTHOR]

We report on the development of direct diode laser source with high-power and high reliability. The laser source was realized by the polarization and wavelength combination of four diode laser stacks. When at the operating current of 122 A, the source was capable of producing 10,120 W output while maintaining 46% electro-optical conversion efficiency. The maximum temperature on the lens was decreased from 442.2 K to 320 K by utilizing an efficient thermal dissipation structure, and the corresponding maximum von Mises stress was reduced from 75.4 MPa to 14 MPa. In addition, a reliability test demonstrated that our laser source was reliable and potential in the applications of laser cladding and heat treatment. [ABSTRACT FROM AUTHOR]

With the wide application of remote sensing technology, target detection based on deep learning has become a research hotspot in the field of remote sensing. In this paper, aimed at the problems of the existing deep-learning-based desert land intelligent extraction methods, such as the spectral similarity of features and unclear texture features, we propose a multispectral remote sensing image desert land intelligent extraction method that takes into account band information. Firstly, we built a desert land intelligent interpretation dataset based on band weighting to enhance the desert land foreground features of the images. On this basis, we introduced the deformable convolution adaptive feature extraction capability to U-Net and developed the Y-Net model to extract desert land from Landsat remote sensing images covering the Inner Mongolia Autonomous Region. Finally, in order to analyze the spatial and temporal trends of the desert land in the study area, we used a structural equation model (SEM) to evaluate the direct and indirect effects of natural conditions and human activities, i.e., population density (PD), livestock volume (LS), evaporation (Evp), temperature (T), days of sandy wind conditions (LD), humidity (RH), precipitation (P), anthropogenic disturbance index (Adi), and cultivated land (CL). The results show that the F1-score of the Y-Net model proposed in this paper is 95.6%, which is 11.5% more than that of U-Net. Based on the Landsat satellite images, the area of desert land in the study area for six periods from 1990 to 2020 was extracted. The results show that the area of desert land in the study area first increased and then decreased. The main influencing factors have been precipitation, humidity, and anthropogenic disturbance, for which the path coefficients are 0.646, 0.615, and 0.367, respectively. This study will be of great significance in obtaining large-scale and long-term time series of desert land cover and revealing the inner mechanism of desert land area change. [ABSTRACT FROM AUTHOR]

A photoionization detector (PID) is well known for its high sensitivity, large dynamic range, and non-destructive vapor detection capability. However, due to its tardy response, which results from the relatively large ionization chamber and dead volume, the application of the PID in gas chromatography (GC) has been limited. Here, we developed a rapid, flow-through, and highly sensitive microfluidic PID that was microfabricated directly on a conductive silicon wafer. The microfluidic PID has a significantly reduced ionization chamber volume of only 1.3 μL, nearly 10 times smaller than that of state-of-the-art PIDs and over 100 times smaller than that of commercial PIDs. Moreover, it has virtually zero dead volume due to its flow-through design. Consequently, the response time of the microfluidic PID can be considerably shortened, ultimately limited by its residence time (7.8 ms for 10 mL min−1 and 78 ms for 1 mL min−1). Experimentally, the response of the microfluidic PID was measured to be the same as that of the standard flame ionization detector with peak full-widths-at-half-maximum of 0.25 s and 0.085 s for flow rates of 2.3 mL min−1 and 10 mL min−1, respectively. Our studies further show that the microfluidic PID was able to detect analytes down to the picogram level (at 3σ of noise) and had a linear dynamic range of six orders of magnitude. Finally, because of the very short distance between the electrodes, low voltage (＜10 VDC, over 10 times lower than that in a regular PID) can be used for microfluidic PID operation. This work will open a door to broad applications of PIDs in gas analyzers, in particular, micro-GC and multi-dimensional GC. [ABSTRACT FROM AUTHOR]

Scheelite ores endolithic arsenic (As) is commonly removed as a detrimental impurity element in the process of tungsten metallurgy. However, arsenic can refine tungsten grains significantly which was found by our team. In this study, refining mechanisms of arsenic in the hydrogen reduction process of tungsten oxide were discussed in detail by X-ray diffraction, scanning electron microscope and transmission electron microscope. The results showed that the WAs 2 intermediate phases played an important role as heterogeneous nucleation core for tungsten during the nucleation process. Moreover, the process of chemical vapor transport was hampered by volatilization of arsenic, which inhibited the growth of tungsten particles. The above two effects resulted in the W–1%As composite powder with the average size of about 80 nm in diameter. [ABSTRACT FROM AUTHOR]

Despite having caused one of the greatest medical catastrophies of the last century through its teratogenic side-effects, thalidomide continues to be an important agent in the treatment of leprosy and cancer. The protein cereblon, which forms an E3 ubiquitin ligase compex together with damaged DNA-binding protein 1 (DDB1) and cullin 4A, has been recently indentified as a primary target of thalidomide and its C-terminal part as responsible for binding thalidomide within a domain carrying several invariant cysteine and tryptophan residues. This domain, which we name CULT (cereblon domain of unknown activity, binding cellular ligands and thalidomide), is also found in a family of secreted proteins from animals and in a family of bacterial proteins occurring primarily in δ-proteobacteria. Its nearest relatives are yippee, a highly conserved eukaryotic protein of unknown function, and Mis18, a protein involved in the priming of centromeres for recruitment of CENP-A. Searches for distant homologs point to an evolutionary relationship of CULT, yippee, and Mis18 to proteins sharing a common fold, which consists of two four-stranded β-meanders packing at a roughly right angle and coordinating a zinc ion at their apex. A β-hairpin inserted into the first β-meander extends across the bottom of the structure towards the C-terminal edge of the second β-meander, with which it forms a cradle-shaped binding site that is topologically conserved in all members of this fold. We name this the β-tent fold for the striking arrangement of its constituent β-sheets. The fold has internal pseudosymmetry, raising the possibility that it arose by duplication of a subdomain-sized fragment. [ABSTRACT FROM AUTHOR]

To attain overall recognition of the effect of Nakagami-m channel parameters on the second-order statistics and to present a guide to the design and configuration of systems, we investigate the average level crossing rate (LCR) and average fading duration (AFD) of multiuser single relay cooperation wireless communications, in which the multiple mobile users communicate with base station under the help of single relay. On the basis of the statistical channel state information (CSI) between mobile users and relay, a single user is selected to communicate with base station. For the multiuser relay cooperation communications, we first present the integral expressions to the LCR and AFD of equivalent end-to-end envelope by using strict mathematical proof. Then with appropriate approximation, we obtain the closed-form solutions to the upper and lower bounds of average LCR and AFD as well as the ones of Laplace approximation. Finally, on the basis of the derivations, we validate the approximations to LCR and AFD, and investigate the effect of the system parameters on LCR and AFD. The comparison results show that the derivations match well the simulations, and the exact values can be bounded by the obtained upper and lower bounds. [ABSTRACT FROM AUTHOR]