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An equiatomic CoCrFeNiMn High Entropy Alloy (HEA) was in-situ deposited by the powder-bed arc additive manufacturing (PBAAM) process for the first time. Comparative research was conducted on the evolution of phase, crystallographic orientation, dislocation morphology, precipitation, and mechanical performance with the accumulation of inter-layer remelting times. The experimental outcomes manifested that the PBAAMed CoCrFeNiMn HEA consists of a stable solid-solution FCC structure, with decreased lattice parameter but slightly increased (full width at half maximum) FWHM as the accumulation of the inter-layer remelting. The {001}<100> cube texture with a weakened texture intensity was detected with an increment of inter-layer remelting frequency from once to 5 times, yet it was transformed into {011}<100> Goss texture with a further increase to 7 times. Additionally, the mean grain diameter distinctly decreased, while the volume fraction of (low angle grain boundaries) LAGBs and dislocation density remarkably added up as the accumulated inter-layer remelts. Predominant cellular substructure generated in all process conditions and could be easily differentiated by elemental segregation. Both the σ and M 23 C 6 Cr-rich precipitates in nano-scale and submicron MnS precipitate were detected on the grain boundaries of the PBAAMed deposited components, with a rather sparse distribution. Speaking of mechanical performance, the YS, UTS, and hardening rate are generally increased while the UE is gradually decreased as increased inter-layer remelting times. The studied PBAAMed CoCrFeNiMn HEA possesses comparable mechanical performances with the counterparts of laser-deposited and as-cast ones. The strengthening mechanisms of the studied material are predominantly the grain boundary strengthening and dislocation strengthening. This investigation would be a valuable resource in the research field of fabricating HEA alloys with acceptable microstructure and properties using the PBAAM method. [ABSTRACT FROM AUTHOR]

Magnesium and its alloys are significant superior metallic materials for structural components in automobile and aerospace industries due to their excellent physicomechanical properties. The Mg–rare earth (RE) systems have attracted great interests because RE additions can improve both the deformability and the strength of Mg alloys through solid solution strengthening and precipitation hardening mechanisms. This paper focuses on the interface stability, together with thermodynamics and kinetics of nucleation and growth of the key phases and matrix phases in Mg–RE alloys. In this paper, the theory and recent advances on Mg–RE alloys, especially for the interface stability, thermodynamics and kinetics of nucleation and growth of the key phases and matrix phases, together with their relationships with micro-structures, and macroscopic properties, are reviewed. By combining the thermodynamics/kinetics integrated simulations with various advanced experimental techniques, "reverse" design of Mg–RE alloys starting from the target service performance is put forward as a kind of scientific paradigm with rational design. [ABSTRACT FROM AUTHOR]

Mo 2 AlB 2 is a new MAB phase that has been observed in thin foils of MoAlB during TEM observation and in NaOH etched MoAlB samples. However, the structural characteristics, chemical bonding and properties of this new compound have not been investigated. In this work, geometry optimized crystal structure of Mo 2 AlB 2 is obtained and its stability, elastic and thermal dynamic properties are investigated. Mo 2 AlB 2 is stable in Al lean conditions, which is consistent with the exiting experimental results. It is also gauged as a damage tolerant or quasi-ductile ceramic based on the low Pugh's shear to bulk modulus ratio (G / B = 0.544) and positive Cauchy pressure in all three crystallographic directions, which is underpinned by the metallic bonding. Mo 2 AlB 2 also exhibits high stiffness which is attributed to the strong B–B covalent bond chains within its crystal structure. Due to the anisotropic chemical bonding, Mo 2 AlB 2 has anisotropic thermal expansion coefficients α a = 6.19 × 10–6 K1, α b = 12.13 × 10−6 K–1, α c = 6.66 × 10−6 K–1, respectively, along a , b and c directions in the temperature range between 300 and 1500 K. The heat capacity from 300 to 1500 K can be described as C p = 120.32 + 0.01648 T − 2.597 × 106T−2 (J∙mol–1∙K–1). The elastic constants decrease almost linearly with temperature. The elastic constants representing the resistance to principle deformation (c 11 , c 22 and c 33) decrease in faster rates than those representing shear deformation resistance (c 44 , c 55 and c 66). Correspondingly, bulk and Young's modulus decrease in faster rates than shear modulus. In light of the structure-property relations of Mo 2 AlB 2 , it is suggested that future damage tolerant ceramics can be designed by putting stiff covalent bonding units into soft metallic bonding box to obtain both high stiffness and quasi-ductility. [ABSTRACT FROM AUTHOR]

In order to find the best operating conditions, the extraction of phenol was studied from a simulate solution by using a liquid membrane emulsion (EML) and a factorial design. Span 80 was used as a surfactant, NaOH as an encapsulating agent, and three types of oil phase: canola oil, canola oil/octane mixture, and canola oil/paraffin mixture. The study of the simple emulsions gave as result that the more stable emulsions were canola oil and the mixture of canola oil/paraffin. These are stable for 2 days, while emulsions of canola oil/octane are not, for they get separated. The maximum extraction was the 77,8 mg/L, using the mixture of the oil canola/paraffin and 75,9 mg/L by just using canola oil as oil phase, achieving extraction percentages of 61,1% y 59,6%, respectively. As a result of the factorial design, none of the effects and interactions were significant, which is attributed to the saturation of the encapsulating agent. [ABSTRACT FROM AUTHOR]

Abstract Epidemiologic studies often report health risk due to short-term air pollution exposure through examination of lagged association, expressing manifestation of population health effects over time. We develop a new approach to the problem of lagged manifestation of air pollution exposure: synthetically lagged models. This approach also generalizes to other lagged time series regression models. [ABSTRACT FROM AUTHOR]

The construction of time series networks in complex systems facilitates the investigation of information interaction mechanisms among subsystems. As widely used causal relationship measurement techniques, Granger causality (GC) is applicable to linear coupling, and information loss is a problem with transfer entropy based on permutation. In order to reasonably analyze the evolution of information transfer between nonlinear signals, we develop a novel causality inference method. In this paper, phase increment transfer entropy (PITE) is proposed, which performs increment symbolic processing on the phase series of signals, taking into account both sign and magnitude. PITE displays effectiveness in simulation experiments, and is more robust than baseline models that measure phase series information transfer of signals. Furthermore, PITE provided evidence that the information transfer between electroencephalogram (EEG) signals of healthy individuals and patients with Attention Deficit Hyperactivity Disorder (ADHD) differs. K-Nearest Neighbors (KNN) is utilized for categorizing subjects based on the causality network, demonstrating the effectiveness of PITE for assessing ADHD and quantifying brain information transfer. The proposed method will provide a novel idea for EEG-based disease research, and help to develop a broader understanding of causality networks. • Extract the instantaneous phase of the signal. • The increment procedure is introduced to symbolize the phase series. • Phase increment transfer entropy is proposed to construct causal networks. • Analyze EEG information transfer in Attention Deficit Hyperactivity Disorder. • Diagnose Attention Deficit Hyperactivity Disorder with the proposed method. [ABSTRACT FROM AUTHOR]

Frequency division modulation enables fast and highly accurate detection of multiple signals, but its spectrum utilization is extremely low. Of course, existing methods improve the spectrum utilization by using quadrature signals as carriers, but it requires the carrier generation to be synchronized with the start of the acquisition. This is difficult to achieve when the carrier generation and the signal acquisition are not controlled by the same clock. Therefore, this paper proposes a demodulation method for the case where the carrier signal is a pair of quadrature square wave signals and the start of the carrier is not synchronized with the sampling. The method demodulates two signals modulating a pair of quadrature carriers by calculating the phase of one independent carrier signal. In this paper, three-wavelength multispectral images are acquired, and the demodulation results are compared with those acquired by the time-division method. The results show that there is a high similarity between the two, which proves the effectiveness of the method proposed in this paper, improves spectrum utilization, and is useful for the acquisition of multiplexed signals. [ABSTRACT FROM AUTHOR]

This paper proposes quaternion polar harmonic Fourier moments (QPHFM) for color image processing and analyzes the properties of QPHFM. After extending Chebyshev–Fourier moments (CHFM) to quaternion Chebyshev-Fourier moments (QCHFM), comparison experiments, including image reconstruction and color image object recognition, on the performance of QPHFM and quaternion Zernike moments (QZM), quaternion pseudo-Zernike moments (QPZM), quaternion orthogonal Fourier-Mellin moments (QOFMM), QCHFM, and quaternion radial harmonic Fourier moments (QRHFM) are carried out. Experimental results show QPHFM can achieve an ideal performance in image reconstruction and invariant object recognition in noise-free and noisy conditions. In addition, this paper discusses the importance of phase information of quaternion orthogonal moments in image reconstruction. [ABSTRACT FROM AUTHOR]

This paper deals with a kind of synchronization of dynamical systems with complex variables which is called generalized complex modified hybrid function projective synchronization (GCMHFPS) of time delay complex chaotic (hyperchaotic) systems. In other words, that the time delay complex systems can be synchronized up to a complex function transformation matrix. Moreover, the elements of the transformation matrix are complex functions of the states of drive system and time, where this matrix is not square. The idea of an active control method based on complex Krasovskii–Lyapunov functional is used to achieve GCMHFPS of time delay complex systems. Furthermore, based on the non-diagonal complex function transformation matrix, the modules and phases errors between one state of the complex response system and more than one of the states of the drive system are studied which have not been discussed before as far as we know. The analytical expression regarding the stability of this technique is derived and excellent agreement is found upon comparison with numerical calculations. In particular, we show through studying the time evolution of error, modulus and phase that the proposed scheme is effective for controlling time delay complex systems. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the shortterm safety and tolerability of an antimalarial herbal medicinal product (PR 259 CT1) consisting of a quantified 80% ethanol extract from the stem bark of Nauclea pobeguinii when given orally to healthy adult male volunteers. The amount of the major alkaloid strictosamide in the extract was determined by a validated HPLC method and was shown to be 5.6%. The herbal preparationwas formulated in a gelatine capsule form containing 500 mg of PCR 259 CT1. A sample of 15 healthy male volunteers, selected using the Lot Quality Assurance of Sampling (LQAS) method, was eligible for inclusion after fulfilment of the inclusion criteria and clinical examination by a physician. The volunteers were treated in an outpatient clinic with a drug regimen of two 500 mg capsules three times daily (each eight hours) for seven days, during meals. Safety and tolerability were monitored clinically, haematologically, biochemically and by electrocardiographic (ECG) examination at days 0, 1, 3, 7 and 14. Adverse effects were recorded by self-reporting of the participants or by detection of abnormalities in clinical examinations by a physician. The oral administration of PR 259 CT1 at high doses of 2 × 500mg/capsule/day for 7 days was found to induce no significant changes in the concentration levels of all investigated haematological, biochemical, electrocardiogram and vital sign parameters and physical characteristics after 14 days of treatment compared to those seen in the baseline data. The concentration levels of all evaluated parameters were within the normal limits as reported in the literature. All adverse events noted were mild and self-resolving including increase of appetite (33%), headache (20%) and nausea (20%). Other minor side effects were insomnia, somnolence and asthenia (7%). Thus, PR 259 CT1 presented a significant safety and tolerability in healthy volunteers to allow its further development by starting a phase II clinical trial. [ABSTRACT FROM AUTHOR]

Time analog-to-digital converters (TADs) based on the power-supply voltage dependence of CMOS gate propagation delay time can be constructed solely of CMOS digital circuits and are characterized by output of the time integral of input voltage, with no dead time. This paper describes digital quadrature detection (DQD) by TAD (TAD-DQD). With TAD-DQD, the in-phase and quadrature components of the input signal, including amplitude and phase information, can be obtained simply by adding and subtracting AD-converted TAD output using a sampling frequency that is four times the carrier frequency of the target signal. As an example of the application of TAD-DQD, the standard-time and frequency-signal receiver circuits of a radio-controlled clock/watch are shown, and the experimental results demonstrate that the time code can in fact be received. [ABSTRACT FROM AUTHOR]

This paper deals with the statistical properties of the two-dimensional dual-tree complex wavelet transform (DT-CWT) coefficients of a Gaussian distributed signal both in the Cartesian and polar forms. The first level of decomposition of the DT-CWT uses the wavelet filters that form only an approximate Hilbert-pair, while those at the higher levels form almost an exact Hilbert-pair. Hence, a significant correlation exists between the quadrature-filtered coefficients of the two trees in the first level of decomposition as compared to the other levels. As a consequence, in the Cartesian representation, the real and imaginary components of the complex coefficients are modeled as independent zero-mean Gaussian having unequal variances for the first level of decomposition and equal variances for the higher levels. In the polar representation, the magnitude components are modeled by a generalized Gamma probability density function (PDF) for the first-level decomposition and a Rayleigh PDF for the higher levels. The corresponding phase components are modeled by an analytic PDF. The Monte Carlo simulations show that the proposed PDFs of the transform coefficients match very well with the empirical ones. It is shown that the moments of the corresponding PDFs closely approximate the estimated sample moments. Finally, two techniques, namely, maximum a posteriori-based estimation and phase-based ridge detection are developed using the proposed PDFs. Simulation studies are carried out showing that the use of the proposed techniques provides improved estimation and detection performance of images in a noisy environment. [ABSTRACT FROM AUTHOR]

Experiments in high energy physics (HEP) operate at the forefront of detector technology, electronics, data acquisition (DAQ), data analysis, and computing. With the advent of high-energy accelerators running at large beam intensities, there is a great demand for radiation-hard high speed protocol for data transmission. Along with the detector data, communication signals like trigger, timing and control (TTC) information plays an important role. The TTC information needs to be transmitted over long distances using asynchronous communication links, which act as a bridge between the front-end radiation hard electronics and the DAQ. Maintaining the timing relationships and synchronization among payloads is an essential pre-requisite for the integrity of the acquired data. However, the phase relationship among the transmitted TTC signals gets disrupted due to the various sources of inter-signal interferences and channel link uncertainties. To address this challenge we have developed a phase alignment logic that can be applied over any asynchronous data-transmission protocol. We have implemented the proposed logic on the widely used radiation tolerant data-transmission protocol, called Gigabit Transceiver (GBT). The DAQ architecture needs to be resilient enough to avoid the loss of data or the errors in physics payload. The principal idea for implementation of the logic is to have an effective strategy to realign the synchronization without the need for power-on reset (PoR). The approach reduces the number of dead cycles that otherwise would have been utilized to minimize the timing errors. The chosen hardware for the experimental setup is 28 nm Stratix-V FPGA from Intel Inc. The benchmark of the system performance is illustrated in terms of the measurements of resource utilization, results of signal integrity, route delays, eye diagram and jitter analysis. [ABSTRACT FROM AUTHOR]

Researchers believe the vaccine, which is already approved in China, could be "suitable for emergency use during the pandemic," though further clinical trials will be needed. [ABSTRACT FROM AUTHOR]

Emulsions that act as a delivery system for beneficial ingredients such as aloe, vitamins, plant extracts, etc., must also be safe, stable and cost-effective. This article discusses the ingredients that go into emulsions and why they are used. [ABSTRACT FROM AUTHOR]