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We consider the global well-posedness and decay rates for solutions of 3D incompressible micropolar equation in the critical Besov space. Spectrum analysis allows us to find not only parabolic behaviors of solutions, but also damping effect of angular velocity in the low frequencies. Based on this observation, we establish the global well-posedness with more general regularity on the initial data. The approach concerns large time behaviors is so-called the Gevrey method which bases on the parabolic mechanics of the micropolar system. This method enables us even to derive decay of arbitrary higher order derivatives by transforming it into the control of the radius of analyticity under a particular regularity. To bound the growth of the radius of analyticity in general L p Besov spaces, we shall develop some new techniques concern Gevrey estimates, especially an extended Coifman-Meyer theory, to cover those endpoint Lebesgue framework. [ABSTRACT FROM AUTHOR]

In this paper we consider the initial value problem to the fractional compressible isentropic generalized Navier-Stokes equations for viscous fluids with one Levy diffusion process in which the viscosity term appeared in the fluid equations is described by the nonlocal fractional Laplace operator. We give one detailed spectrum analysis on a linearized operator and the decay law in time of the solution semigroup for the linearized fractional compressible isentropic generalized Navier-Stokes equations around a constant state by the Fourier analysis technique, which is shown that the order of the fractional derivatives plays a key role in the analysis so that the spectrum structure involved here is more complex than that of the classical compressible Navier-Stokes system. Based on this and the elaborate energy method, the global-in-time existence and one optimal decay rate in time of the smooth solution are obtained under the assumption that the initial data are given in a small neighborhood of a constant state. [ABSTRACT FROM AUTHOR]

The classical solution of the 3-D radiative hydrodynamics model is studied in H k -norm under two different conditions, with and without heat conductivity. We have proved the following results in both cases. First, when the H k norm of the initial perturbation around a constant state is sufficiently small and the integer k ≥ 2 , a unique classical solution to such Cauchy problem is shown to exist. Second, if we further assume that the L 1 norm of the initial perturbation is small too, the i-order (0 ≤ i ≤ k − 2) derivatives of the solutions have the decay rate of (1 + t) − 3 4 − i 2 in H 2 norm. Third, from the results above we can see that for radiative hydrodynamics, the radiation can do the same job as that the heat conduction does, which means if the thermal conductivity coefficient turns to 0, because of the effect of radiation, the solvability of the system and decay rate of the solutions stay the same. [ABSTRACT FROM AUTHOR]

Due to harsh working conditions, rotating blades are prone to failures. Thus, it is urgently needed to monitor blade health. Blade tip timing (BTT) is a promising non-contact vibration technique for rotating blades owing to its high efficiency and long service time. However, due to severe undersampling, traditional spectrum analysis methods are ineffective in identifying characteristic parameters and recovering the power spectrum of vibrations for condition monitoring. To address this issue, this paper proposes a compressed covariance sensing-based BTT (CCS-BTT) method for power spectrum estimation. Specifically, we build a compressed covariance sensing representation model for BTT signal, where the covariance representation can be non-underdetermined owing to the Hermitian Toeplitz structure of the covariance matrix. Then, a universal covariance sampling pattern (UCSP) is derived to ensure the complete covariance information can be efficiently recovered without sparsity constraint. By utilizing the inherent periodicity, the derived UCSP significantly improves the efficiency of BTT measurement. Moreover, for practicality, we present a series of optimized layouts based on UCSP that cover almost all possible cases of probe numbers in BTT measurement. Finally, extensive simulations and experiments validate the effectiveness and performance of CCS-BTT. By shifting the perspective from the signal itself to its covariance, CCS-BTT opens many avenues for the development of BTT signal processing. In addition, the proposed method is expected to be used in deterministic compressive sampling of wide-sense stationary signals. • A compressed covariance representation for blade tip timing (BTT) signal is built. • A universal covariance sampling pattern is derived to ensure recoverability. • We improve the BTT measurement efficiency by utilizing the inherent periodicity. • The power spectrum of BTT signal can be estimated without sparsity constraint. • We provide a series of practical layouts that cover almost all cases in BTT. [ABSTRACT FROM AUTHOR]

• A novel approach for single channel speech enhancement is presented, using the colored spectrograms. • Using deep neural network for spectrogram denoising and regression neural network for translating the colors of denoised spectrograms to short time Fouier transform (STFT) magnitudes. • Output is comparable to the state-of-the-art baseline models at a much reduced computational cost. Speech enhancement concerns the processes required to remove unwanted background sounds from the target speech to improve its quality and intelligibility. In this paper, a novel approach for single-channel speech enhancement is presented using colored spectrograms. We propose the use of a deep neural network (DNN) architecture adapted from the pix2pix generative adversarial network (GAN) and train it over colored spectrograms of speech to denoise them. After denoising, the colors of spectrograms are translated to magnitudes of short-time Fourier transform (STFT) using a shallow regression neural network. These estimated STFT magnitudes are later combined with the noisy phases to obtain an enhanced speech. The results show an improvement of almost 0.84 points in the perceptual evaluation of speech quality (PESQ) and 1 % in the short-term objective intelligibility (STOI) over the unprocessed noisy data. The gain in quality and intelligibility over the unprocessed signal is almost equal to the gain achieved by the baseline methods used for comparison with the proposed model, but at a much reduced computational cost. The proposed solution offers a comparative PESQ score at almost 10 times reduced computational cost than a similar baseline model that has generated the highest PESQ score trained on grayscaled spectrograms, while it provides only a 1 % deficit in STOI at 28 times reduced computational cost when compared to another baseline system based on convolutional neural network-GAN (CNN-GAN) that produces the most intelligible speech. [ABSTRACT FROM AUTHOR]

We propose a novel technique to estimate the channel characteristics for robust speech recognition. The method focuses on reliable time–frequency speech patches which are highly independent of the noise condition. Combined with a root-based approximation of the logarithm in the MFCC computation, this reduces the variance caused by the noise on the spectral features, and therefore also the constrain on the acoustic model in a multi-style training setup. We show that compared to the standard mean normalization, the proposed method estimates the channel equally well under clean conditions and better under noisy conditions. When integrated in the feature extraction pipeline, we show improvements in speech recognition accuracy on noisy speech and a status quo on clean speech. Our experiments reveal that this method helps the most for generative models that need to model the complex noise variability, and less so for discriminative models, which can learn to ignore noise instead of accurately modeling it. Our approach outperforms the state of the art on the noisy Aurora4 task. • Conventional mean-based channel estimate is sensitive to noise. • Focusing on spectral peaks combined with root compression improves robustness. • Feature engineering remains important for neural network based speech recognition, especially when they use generative modeling components. • New state-of-the-art results on Aurora4 task. • Insight into how a multiplicative channel in combination with additive noise affects the spectrum. [ABSTRACT FROM AUTHOR]

A new set of radiative parameters (oscillator strengths and transition probabilities) was obtained for the most intense spectral lines in Re III, Re IV and Re V ions. These parameters were calculated using two independent methods, namely the pseudo-relativistic Hartree–Fock approach including core-polarization effects (HFR+CPOL) and the fully relativistic multiconfiguration Dirac–Hartree–Fock (MCDHF) approach. Detailed comparisons between the results obtained from these two methods as well as with the few data available in the literature allowed us to estimate the precision of the calculations carried out. The radiative parameters reported in the present paper concern a total of 368 electric dipole (E1) transitions in Re III, Re IV and Re V covering the ultraviolet spectral region from 655 to 2135 Å. These are of great interest for the analysis of spectra emitted by plasmas in nuclear fusion reactors, such as ITER where rhenium can be produced by neutron bombardment of the tungsten divertor wall, as well as for the investigation of astrophysical spectra observed from chemically peculiar stars or from kilonovae where rhenium can be produced by the nucleosynthesis r-process. [ABSTRACT FROM AUTHOR]

Being a problem that has long plagued the field of electrochemical machining process, real-time and high precision monitoring of the interelectrode gap is a difficult task. In this research, we introduce a method for monitoring the interelectrode gap using a tool electrode equipped with an optical fiber sensor. This method does not require large numbers of parameters such as conductivity of the electrolyte, electric current density distribution, shape of the electrodes, etc. and therefore reduces the complexity of the monitoring system. The optical fiber, moving together with the tool, forms an open Fabry-Pérot interferometer consists of a reflection surface of the fiber end and a reflection surface of the workpiece. Additionally, we introduce a spectrum analysis method specifically designed for the Fabry-Pérot interferometer spectrum. This method provides the absolute distance between the optical fiber and the target, demonstrating robustness to noise and abrupt spectrum changes. Consequently, it can be utilized in harsh environments for high-precision distance monitoring, a task challenging for traditional methods using optical interferometers. With the proposed method, a difference of ±2.5 μm was achieved compared with demodulating the spectrum manually. The average process time of a spectrum with 16,001 sampling points and a distance resolution of 1 nm is 0.148 s. Real-time monitoring and control of an electrochemical machining process was also implemented. The interelectrode gap was successfully maintained at 200 ± 5 μm throughout the machining process and the final machining depth measured by the proposed method and an optical measurement system has a difference of 6 μm. [ABSTRACT FROM AUTHOR]

Diagnosing the rolling bearings using vibration signals requires advanced signal analysis methods. The envelope spectrum analysis method is commonly used, but it requires the determination of the frequency band in which the signal modulation occurs. This paper proposes a method that does not have such limitations and it is based on copula technique applied to wheel bearing signals. Our approach allows to efficiently identify faults using low energy components of the signal estimated via the PCA method. While it is standard to analyze time series autocorrelation function, proposed multifeature autocorrelation analysis finds multiple dominating contribution to joint distribution of values shifted by various time lags. This way it finds also more subtle statistical dependencies, here suggesting damage of bearing. Proposed approach was verified in the laboratory conditions for different kinds of defaults in different positions. • Alternative fault identification method of rolling bearing. • Multifeature autocorrelation with PCA in rolling bearing diagnostics. • 12 different cases analyzed, all proved successful for our method. • Special laboratory stand constructed to verify proposed method. [ABSTRACT FROM AUTHOR]

This paper presents an analysis of the correlation between setback and high-impact test loadings using the shock response spectrum (SRS). The modal analysis of the electronic assembly structure is implemented to determine the frequency range for the SRS analysis. A preliminary test of the high-impact tester is conducted with a reference impact velocity. Based on experimental data, finite element (FE) simulation is employed to predict the acceleration states at different impact velocities. The acceleration curves generated from FE simulation are included in the shock response spectrum for the correlation analysis. A proposed impact velocity is expected to cause a similar damage to the electronic assembly structure. This study provides valuable insight into the relationship between setback and high-impact test loadings, as well as a method for predicting and evaluating the potential damage to electronic assembly structures during high-impact testing. [ABSTRACT FROM AUTHOR]

The initial value problems of bipolar isentropic/non-isentropic compressible Navier-Stokes-Maxwell (CNS-M) systems arising from plasmas in R 3 are studied. The main difficulty of studying the bipolar isentropic/non-isentropic CNS-M systems lies in the appearance of the electromagnetic fields satisfying the hyperbolic Maxwell equations. The large time-decay rates of global smooth solutions with small amplitude in L q (R 3) for 2 ≤ q ≤ ∞ are established. For the bipolar non-isentropic CNS-M system, the difference of velocities of two charged carriers decay at the rate (1 + t) − 3 4 + 1 4 q which is faster than the rate (1 + t) − 3 4 + 1 4 q (ln ⁡ (3 + t)) 1 − 2 q of the bipolar isentropic CNS-M system, meanwhile, the magnetic field decay at the rate (1 + t) − 3 4 + 3 4 q (ln ⁡ (3 + t)) 1 − 2 q which is slower than the rate (1 + t) − 3 4 + 3 4 q for the bipolar isentropic CNS-M system. The approach adopted is the classical energy method but with some new developments, where the techniques of choosing symmetrizers and the spectrum analysis on the linearized homogeneous system play the crucial roles. [ABSTRACT FROM AUTHOR]

In this work, we present results on stability and hyperbolicity of equilibria for a scalar nonlocal one-dimensional quasilinear parabolic problem. We show that this nonlocal version of the well-known Chafee-Infante equation bears some resemblance with the local version. However, its nonlocal characteristic requires a fine analysis of the spectrum of the associated linear operators, a lot more elaborated than the local case. The saddle point property of equilibria is shown to hold for this quasilinear model. [ABSTRACT FROM AUTHOR]

• A hybrid approach based on modulation transfer and vibroacoustic modulation is used for damage detection and localisation. • The damage indicators are calculated from frequency components obtained by the proposed algorithm. • The experiment is conducted on both the damaged and undamaged beams. • The complementarity of methods based on modulation transfer and vibroacoustic modulation phenomena. • Manifestation of various non-linear mechanisms responsible for modulation transfer and vibroacoustic modulation. This paper describes a hybrid approach to fault detection by using modulation transfer and vibroacoustic modulation. The work aims to locate faults and study the components of the response signals. This research is relevant for two reasons. The first is the small amount of research concerning hybrid modulation methods in fault localisation. The second is related to the insufficient knowledge of the response signals composition, which is crucial for fault detection procedures. Thus, the tests were carried out on two beams made of aluminium, one damaged and the other undamaged. The tested structures were excited by two sources. The first was a piezo stack actuator that introduced an amplitude-modulated wave with a modal frequency carrier. The second source was a piezoelectric exciter that introduced a harmonic ultrasonic wave. The tests were performed for several amplitude levels applied to the piezo stack actuator. The recorded responses were processed to calculate frequency spectra and prepare damage index trend charts. The spectrum analysis revealed the presence of components related to the modulation transfer and vibroacoustic modulation phenomenon. The trend analysis indicated that modulation transfer can be applied for damage localisation and complement vibroacoustic modulation techniques. [ABSTRACT FROM AUTHOR]

Blind source separation (BSS) has been demonstrated to be a promising method for operational modal analysis (OMA). However, the conventional BSS-based modal identification methods can only handle the determined or overdetermined identification where the number of sensors must equal or exceed that of active modes, limiting their wider application. Furthermore, the existing methods for underdetermined BSS require sparsity assumption of sources, optimization of model parameters, or structural prior information, undermining the non-parametric and "blind" properties of BSS. This paper proposes a novel method for underdetermined OMA. Firstly, the bandlimited source separation using sinc-dictionaries is performed to efficiently transform the underdetermined problem into several determined or overdetermined ones. An improved second-order blind identification (SOBI) involving Hilbert transform and random time-lagged covariances is then applied for each bandlimited signal to recover modal responses and mode shapes. To attenuate noise, an adaptive singular spectrum analysis (SSA) can be optionally applied to the recovered modal responses for the highly noisy systems. Finally, the natural frequencies and damping ratios are estimated by the single-degree-of-freedom (SDOF) fitting technique. Several numerical examples, an experimental frame case, and a field test of a pedestrian bridge are studied to verify the effectiveness of the proposed strategy. • Bandlimited source separation using the sinc function is proposed. • Transforming the underdetermined problem to determined or overdetermined ones. • Adapting the second-order blind identification to underdetermined modal analysis. • Hilbert transform, random covariances, and adaptive singular spectrum analysis improve performance. • Numerical examples and real-life cases verify the effectiveness. [ABSTRACT FROM AUTHOR]

The performance and mechanism of persulfate consisting of peroxymonosulfate (PMS) and peroxydisulfate (PDS) activation by underwater bubbling plasma (UBP) for the synergistic removal of tetracycline hydrochloride (TCH) were comparatively investigated. Both PMS and PDS addition significantly promoted the removal of TCH in UBP system, indicating persulfate exhibited highly synergistic effect with UBP. Furthermore, enhancing the persulfate dosage, peak voltage and pulse frequency, as well as reducing initial TCH concentration were favorable for the elimination of TCH. Compared with neutral condition, acidic and alkaline condition were advantageous to TCH removal. The presence of coexisting substances including Cl−, SO 4 2− and humic acid (HA) had an adverse effect on TCH degradation, while Fe2+ could improve the removal of TCH. The degradation of ciprofloxacin and metronidazole proved the applicability for other antibiotics degradation of the reaction system. SO 4 −·, ·OH, ·O 2 −, hydrated electrons, O 3 and H 2 O 2 were the active substances responsible for TCH removal. The reduction of aqueous O 3 concentration and enhancement of H 2 O 2 concentration were observed after persulfate addition. UV–vis spectra and TOC analysis illustrated the addition of PMS or PDS facilitated the degradation and mineralization of TCH. 3D-EEMF spectra visually displayed the degradation process of TCH. Plausible degradation routes were deduced based on LC-MS and the toxicities of TCH and its intermediates were evaluated by Toxicity Estimation Software Tool. [Display omitted] • TCH degradation efficiency enhanced significantly after persulfate addition into UBP. • The synergistic factor of UBP/PDS and UBP/PMS reached 1.59 and 2.46, respectively. • Persulfate could be activated by UBP-induced O 3 , hydrated electrons and ultraviolet. • The UBP/persulfate system presented applicability for other antibiotics degradation. • ∙OH, SO 4 −·, ·O 2 −, and e aq were all involved in the degradation of the TCH. [ABSTRACT FROM AUTHOR]

Chatter is a notoriously unstable phenomenon that can adversely affect both surface quality and machining efficiency. To achieve high-performance machining, the development of online chatter detection is of paramount importance. Nevertheless, changes in chatter frequency with cutting position and noise interference during the thin-walled parts milling process present significant challenges to chatter detection. To tackle this issue, an adaptive frequency band attention module (AFBAM) is designed, which is characterized by not relying on prior knowledge (namely modal parameters, frequency spectrum analysis, etc.), and adaptively enhances the frequency band containing abundant chatter information and reduces noise interference by learning time-frequency domain characteristics of signals. After AFBAM highlights the relevant frequency band of input signal, a discriminative feature attention module (DFAM) is constructed to adaptively recalibrate feature responses of each convolutional layer utilizing the global information. DFAM enhances relevant features and suppresses irrelevant features, thus improving the discriminative feature learning and redundant information suppression abilities of network. In addition, both AFBAM and DFAM exhibit clear physical interpretability, which improves the interpretability of network. Based on AFBAM and DFAM, an interpretable anti-noise convolutional neural network for online chatter detection, named AD-CNN, is established. Milling experiments with pocket-shaped thin-walled parts are conducted under different cutting parameters. The results show that the proposed method enables better detection accuracy and anti-noise ability than other state-of-the-art methods. Furthermore, visualization analysis of AFBAM and DFAM brings new insights into the interpretability of convolutional neural network in the field of chatter detection. [ABSTRACT FROM AUTHOR]

Here we demonstrate that the antigen binding function of a humanized anti-cocaine mAb (h2E2) can be directly and easily determined using simple and inexpensive absorption spectroscopy and dyes commonly used for differential scanning fluorimetry, such as DASPMI and SYPRO Orange. Therapeutic monoclonal antibodies are commonly formulated in buffers which can interfere with necessary functional assays, containing additives and excipients such as mild detergents. Using the undiluted therapeutic product h2E2 mAb in its formulation buffer containing 0.01% polysorbate 80, the number of antigen/cocaine binding sites can be determined by the increase in absorbance (for DASPMI dye) or by the decrease in absorbance maximum wavelength (for SYPRO Orange dye), confirming proper function of the therapeutic mAb product. This ligand-induced visible dye absorption change can also be used to qualitatively evaluate the relative affinities of various metabolites of cocaine. These results are confirmed and extended by binding data obtained in the same formulation buffer using intrinsic tyrosine and tryptophan fluorescence quenching by cocaine, as well as by differential scanning fluorimetry. Interestingly, the binding of the cocaine metabolite norcocaine was demonstrated to be differentially affected by the pH 6 formulation buffer used for this mAb, presumably due to the differential ionizability of the demethylated norcocaine tropane ring nitrogen. This simple, direct, and inexpensive technique should prove useful for evaluation of other small molecule binding mAbs directly in their formulation buffers containing detergent, allowing rapid functional assessment of the produced therapeutic proteins. Image 1 • Cocaine binding of clinically formulated mAb is quantitated by visible dye absorption. • Functional ligand binding sites easily and rapidly measured by dye absorbance changes. • Cocaine metabolite relative affinities are qualitatively assessed using DASPMI dye. • This simple and direct method may be applicable to other small molecule directed mAbs. [ABSTRACT FROM AUTHOR]

Deoxynivalenol (DON) contamination of wheat grains is a serious problem in China, and it is necessary to remove contaminated wheat before it enters the consumer market. In this study, visible-near infrared (Vis-NIR) spectroscopy and computer vision techniques were combined to simulate online discrimination between normal and DON-contaminated wheat grains. Naturally growing wheat samples were collected from several of the main wheat-producing areas in China, the reference DON contents were measured by using liquid chromatography serial triple quadrupole mass spectrometer (LC-MS), and then wheat samples were divided into two categories according to the national standard of 1 mg kg−1. The characteristic spectral variables, colour and texture features were extracted and integrated for chemometric analysis. Principal component analysis based on fusion features indicated better clustering than with just spectral features. Subsequently, linear discriminant analysis modelling based on spectra and texture features achieved the best discrimination with an accuracy of 95.06% and 91.36% for calibration and validation sets respectively, which was 5% higher than with just spectral features, and the false positive rates (FPR) were the lowest: 3.41% and 10.42% for calibration and validation sets respectively. The internal scanning results of whole wheat flour indicated that the higher the content of DON, the looser the binding of starch granules, which could cause the textural change of wheat grains. The research showed that Vis-NIR spectroscopy combined with computer vision has the potential to be used in the non-destructive and online detection of DON-contaminated wheat grains; further study on the interference from complex environments is still need for actual online detection. • Vis-NIR spectroscopy and computer vision techniques were combined. • Spectral, texture, colour features were extracted and integrated for chemometric analysis. • Dynamically discrimination of the DON contaminated and normal wheat grains. • Naturally growing wheat grains were collected as samples. • Models based on integrated features provided more accurate discrimination results. [ABSTRACT FROM AUTHOR]

The main purpose of this paper is to investigate mathematically gas discharge. Townsend discovered α - and γ -mechanisms which are essential for ionization of gas, and then derived a threshold of voltage at which gas discharge can happen. In this derivation, he used some simplification such as discretization of time. Therefore, it is an interesting problem to analyze the threshold by using the Degond–Lucquin-Desreux–Morrow model and also to compare the results of analysis with Townsend's theory. Note that gas discharge never happens in Townsend's theory if γ -mechanism is not taken into account. In this paper, we study an initial–boundary value problem to the model with α -mechanism but no γ -mechanism. This problem has a trivial stationary solution of which the electron and ion densities are zero. It is shown that there exists a threshold of voltage at which the trivial solution becomes unstable from stable. Then we conclude that gas discharge can happen for a voltage greater than this threshold even if γ -mechanism is not taken into account. It is also of interest to know the asymptotic behavior of solutions to this initial–boundary value problem for the case that the trivial solution is unstable. To this end, we establish bifurcation of non-trivial stationary solutions by applying Crandall and Rabinowitz's Theorem, and show the linear stability and instability of those non-trivial solutions. [ABSTRACT FROM AUTHOR]

To evaluate the synergetic adsorption capacity of layered double hydroxide (LDH) and photocatalytic reduction property of TiO 2 for aqueous Cr(VI), the Fe 3 O 4 -ZnAl-LDH and TiO 2 composites (FLT) were prepared via sol-gel method. The removal efficiency of FLT composites for Cr(VI) changed with the mass ratio of Fe 3 O 4 -LDH/TiO 2 , and the optimal ratio was 20% (FLT-2). The adsorption efficiencies of 100 mg FLT-2 were 74% and 64% for 20 and 50 mg/L Cr(VI) solution, and the total removal ratios of Cr(VI) were all over 97% after UV irradiation. The experimental data of adsorption kinetic, adsorption isothermal, and photocatalytic reduction were consistent with the pseudo-second-order, Langmuir, and first-order reaction equations, respectively. From the X–ray photoelectron spectra analysis, FLT composites adsorbed Cr(VI) directly via surface complexation, also reduced aqueous Cr(VI) to Cr(III). The photocurrent and electrochemical impedance spectroscopy of FLT composites indicated the photo-induced electron-hole pairs were separated effectively. The regeneration results show that the FLT composites had good stability and reusability after five consecutive cycles. Therefore, FLT composites are promising materials in the disposal of wastewater containing Cr(VI). [ABSTRACT FROM AUTHOR]

Machine learning has been used in NMR in for decades, but recent developments signal explosive growth is on the horizon. An obstacle to the application of machine learning in NMR is the relative paucity of available training data, despite the existence of numerous public NMR data repositories. Other challenges include the problem of interpreting the results of a machine learning algorithm, and incorporating machine learning into hypothesis-driven research. This perspective imagines the potential of machine learning in NMR and speculates on possible approaches to the hurdles. [ABSTRACT FROM AUTHOR]

• Pulse sequences for liquid state NMR continue to evolve. • Triple-resonance bio-NMR schemes have impacted a broad range of NMR experiments. • Careful pulse sequence design is critical as applications become more challenging. Careful pulse sequence design and optimization is critical to the success of a given NMR experiment. Over the past several decades the level of sophistication of NMR pulse sequences has increased tremendously, leading to large spectral sensitivity and resolution improvements, to data sets with far fewer artifacts, and to much more rapid acquisition times, opening up a wide range of applications. Here I briefly highlight how pulse sequence 'engineering' has evolved, focusing on liquid state NMR, and, in particular, on the HNCA-class of triple-resonance experiment. In many respects, the evolution of triple-resonance NMR mirrors the evolution of solution state NMR experiments in general, with 'tricks' that first appeared in triple-resonance pulse sequences or that were motivated by them now incorporated into a broad range of experiments. [ABSTRACT FROM AUTHOR]

A novel dual-scale compact method for solving nonparaxial Helmholtz equations at high wavenumbers is proposed and analyzed. The approach is based on decomposing the axisymmetric transverse domain and governing equation according to interconnected micro and macro regions to maintain the smoothness of the underlying problem. Dual compact strategies are then implemented for acquiring highly accurate and efficient beam propagation computations. Aiming at the highly oscillatory solution features, the paper provides a rigorous analysis on the numerical stability. It is shown that the dual-scaled compact method is asymptotically stable. The analysis also reveals necessary constraints for the conventional stability. Computer experiments including self-focusing beam propagation simulations are conducted with various domain scaling factors to validate the theoretical results. • Dual-scale compact method for solving highly oscillatory Helmholtz problems. • Asymptotic stability analysis at high-wavenumbers for decomposed difference scheme. • Spectrum analysis follows to bound the 2-norm of amplification matrices. • Numerical self-focusing optical beam simulations reinforce reliability of method. • Flexibility in dual-domain scaling factor is favorable in optical beam applications. [ABSTRACT FROM AUTHOR]

• A deformable transfer path premised model presents the vibration signal of planetary gears. • A numerical method presents to quantify signal respecting frequency and amplitude features. • The approaches are practical tools to predict spectral features of planetary gears with defects. • The validity of the methodology is verified by simulation and experimental signals. Planetary gear drives pose complex vibration signals due to that the excitations of the signal are the space-time varying meshing forces and the transfer paths for the excitations are time-varying systems. It brings about difficulties in machine diagnostics field to model, to predict, and to interpret the spectrum mechanism of the signal. This paper suggests a space-time model for this time-varying problem. Premised on deformable-body transfer path, the model formulates the response signal in frequency-domain as an integral transform of the excitations, where the transform kernel is formulated by the product of the Fourier kernel and the Frequency Response Function of the transfer path. A corresponding numerical method is also proposed for the numerical computation of the signal. Comparing with the existing model and method premised on rigid body transfer path, the proposed approach presents higher accuracy on signal prediction and spectral feature interpretation with respect to the frequency, amplitude and modal information. [ABSTRACT FROM AUTHOR]

The cascading process analysis in the D2Δ 5/2 state of copper monoxide molecule. • Ten unreported vibronic bands are presented. • The molecular constants of excited states for 63CuO and 65CuO are obtained. • Cascading processes are found and analyzed in all observed excited states. The electronic spectrum of the copper monoxide molecule (CuO) was investigated in the range of 430–550 nm using laser induced fluorescence spectroscopy and single vibronic level emission spectra. The CuO molecule was produced by a supersonic jet-cooled discharge assisted laser ablation of Cu target. Twenty two vibronic bands were observed and assigned to the electronic transition progressions from the ground state X2П i to excited states C2П 3/2 , C2П 1/2 , D2Δ 5/2 , E2Δ 5/2 , F2П 3/2 , G2Σ−, H2П 3/2 , and I2П 3/2 , of which ten bands were recorded firstly. The molecular constants of the excited electronic states for 63CuO and 65CuO isotopologues were obtained by a rotational analysis of the spectra. Cascading processes in the electronic excited states were found combining the time-resolved single vibronic level emission spectroscopy. The time-dependent radiative decay curves corresponding to different decay processes were recorded and analyzed. [ABSTRACT FROM AUTHOR]

We conducted this study to quantify long-term cropping related changes in soil organic carbon (SOC) stocks and characterize the optical properties of dissolved organic matter (DOM) after a decadal on-farm experiment in Montana, USA. Soil samples (0–50 cm) were collected from minimum till (MT) and no-till (NT) fields under fallow-winter wheat (Triticum aestivum L.; F-W) and pea-winter wheat (Pisum sativum L.; P-W) rotations. Stocks of SOC (0–50 cm) averaged 65.6 Mg C ha−1 and 60.6 Mg C ha−1 for P-W and F-W, respectively. The net SOC accretion rate for P-W equated to 0.61 Mg ha−1 yr−1 relative to F-W. We used absorbance spectroscopy and excitation-emission matrices to characterize DOM composition of samples collected from MT F-W and NT P-W. The two cropping systems exhibited similar estimates of aromaticity (absorbance at 254 nm; 0.33–0.39 a.u.) and humification index (1.83–1.86). Parallel factor (PARAFAC) analysis revealed humic-like (C1, C2), monolignol/amino acid-like (C3), and amino acid-/tannin-like (C4) components with equivalent fluorescent intensities among MT F-W and NT P-W. Fluorescence efficiencies increased with depth, suggesting a shift from larger, plant-like material to smaller, microbial-derived precursors. Overall, we found DOM composition to be minimally affected by cropping systems in this semiarid climate of the northern Great Plains. • Annual cropping sequestered more SOC than fallow-based systems over a 10 year period. • The accretion of SOC within annual cropping occurred at a rate of 0.61 Mg ha−1 yr−1. • Soil DOM bulk optical properties did not respond to changes in decadal SOC stocks. • PARAFAC analysis identified four different fluorescent components of the EEMs. • Sub-soil DOM was comprised of low molecular size constituents. [ABSTRACT FROM AUTHOR]

Abstract We study the internal controllability of a wave equation with memory in the principal part, defined on the one-dimensional torus T = R / 2 π Z. We assume that the control is acting on an open subset ω (t) ⊂ T , which is moving with a constant velocity c ∈ R ∖ { − 1 , 0 , 1 }. The main result of the paper shows that the equation is null controllable in a sufficiently large time T and for initial data belonging to suitable Sobolev spaces. Its proof follows from a careful analysis of the spectrum associated with our problem and from the application of the classical moment method. [ABSTRACT FROM AUTHOR]

• One-color resonance-enhanced (S 1 –S 0) photodissociation of acetylene is studied. • The photolysis produces C 2 C 1 Π g and d 3 Π g states, and a long-lived C 2 H species. • The relative fragment yields are estimated to be C 2 H:C 2 (d) :C 2 (C) = > 40 :4:1. • One-photon photodissociation from S 1 acetylene produces the C 2 H fragment. • One additional photon photolyzes C 2 H to generate C 2 C 1 Π g and d 3 Π g states. One-color (212–220 nm) multi-photon dissociation of acetylene, resonantly enhanced at the one-photon level by the acetylene S 1 –S 0 transition, gives rise to strong photofragment fluorescence signals in the visible and near UV regions. The photofragment fluorescence detection scheme has been applied to obtain rotationally-resolved action-spectra of predissociated S 1 acetylene levels near 47,000 cm−1 Jiang et al.(2018) [1]. In this work, fluorescence signals from the photofragments, generated via individual intermediate S 1 rovibrational levels, are studied in detail, in both flowing gas cell and supersonic jet conditions. In the flow cell setup (∼ 1 Torr), dispersed fluorescence (DF) spectra of the photofragments are obtained. For all three S 1 levels used in the DF experiment (rotational levels of the trans 3 4 , trans 3 5 , and cis 3 1 6 1 vibrational states), we observe C 2 Swan band ( d 3 Π g - a 3 Π u ) and C 2 Deslandres-d'Azambuja band ( C 1 Π g - A 1 Π u ) emissions. In the supersonic jet setup (collision-free), fluorescence time-traces at selected wavelength regions are analyzed. In addition to the two C 2 emission bands, we observe a long-lived (> 3 μ s) visible fluorescence signal, which is likely due to emission from C 2 H fragments. Based on our analysis of the DF spectra and the fluorescence time-traces obtained in the supersonic jet apparatus, we propose that the long-lived C 2 H species is generated by one-photon photodissociation of S 1 acetylene, and an additional photon photolyzes the C 2 H fragment into the C 2 C and d states. [ABSTRACT FROM AUTHOR]

The photophysical properties of chromophores react very sensitively upon changes of their electrostatic environment. This allows conformational fluctuations of a protein to be monitored by optical spectroscopy via the fluctuations of the spectral signatures of chromophores that are embedded in the protein's matrix. However, to be successful as an approach this requires that the structural fluctuations within the proteins would occur synchronously. This restriction can be overcome by studying the proteins on an individual basis. In this contribution, we illustrate this approach on the example of the peripheral light-harvesting complexes from photosynthetic purple bacteria that contain bacteriochlorophyll a as natural cofactors. [ABSTRACT FROM AUTHOR]

In this work, Ti-Sn-Sb/γ-Al 2 O 3 particle electrodes were prepared and employed for the degradation of oxytetracycline (OTC) by three-dimensional electrocatalytic technology. Factors associated with the preparation of Ti-Sn-Sb/γ-Al 2 O 3 particle electrodes were investigated. The effects of initial concentration, conductivity, pH value, aeration intensity, current density, plate spacing, and particle electrode dosage on OTC removal were studied. The removal rate of OTC and total organic carbon were achieved approximately 92.0% and 41.0% under the optimal operating condition, respectively. In addition, Ti-Sn-Sb/γ-Al 2 O 3 particle electrode was analyzed by Fourier Transform Infrared spectroscopy (FT-IR), scanning electron microscope (SEM), energy dispersive spectrum analysis (EDX), X-Ray Fluorescence Spectrometer (XRF), and X Ray Diffraction analysis (XRD), which indicated that a significant amount of TiO 2 , SnO 2 , and Sb 2 O 3 were formed on the surface of Ti-Sn-Sb/γ-Al 2 O 3 particle electrode. It was also observed that the primary function of Ti-Sn-Sb/γ-Al 2 O 3 particle electrode in the three-dimensional electrode electrolysis process is the strong oxidizing function of ·OH for degrading OTC. Consequently, the analysis of degradation products of oxytetracycline (OTC) demonstrates. In addition, the results and conclusions of this study provide a methodological basis and engineering practice basis for removing the low concentration of antibiotics in water. Image 1 • Sodium alginate embedding method is used for preparing Ti-Sn-Sb/γ-Al 2 O 3 particle electrode. • Possible degradation mechanism of oxytetracycline is investigated and discussed. • Ti-Sn-Sb/γ-Al 2 O 3 particle electrode shows excellent electrocatalytic oxidation capacity. • It has positive significance for removing low concentration antibiotics in water. [ABSTRACT FROM AUTHOR]

Based on the mixed effects of the defect mode and interface state, a one-dimensional (1D) photonic crystal (PC) structure used for simultaneous gas concentration and temperature measurement is proposed. Using multiple physical field numerical module of the finite element method, the reflection spectrum with two relatively independent peaks is formed. And the wavelengths of the reflection peaks can be shifted when the concentration of the gas filled in the photonic crystal and environment temperature are changed. The defect layer thickness, metal layer thickness and period of photonic crystal are optimized. Taking the toluene as temperature-sensing medium, and the mixture of air and ethylene as gas-sensing medium, the relationships between the reflection peaks and related physical quantities are studied. Gas concentration and temperature can be measured by analyzing the relative shift of position of two reflection peaks in reflection spectrum. The results show that gas sensitivity is 500pm/1% ranging from 0% to 3% and its Q factor is 471.4. Temperature sensitivity is 88.7 pm/°C ranging from −20 °C to 70 °C and its Q factor is 415.7. The structure is simple, highly sensitive, and dual-parameter sensing. The study has reference value for simultaneously detecting harmful gas leakage and temperature in the polluted environment. • Hybrid sensing mechanism based on photonic crystal defect state and interface state. • Gas concentration measurement and temperature measurement at the same time. • Multiple physical field numerical module of the finite element method. [ABSTRACT FROM AUTHOR]

• Totally 63 bands were resolved in 18,900 – 23,500 cm-1 region, and two electronic transitions were newly identified. • (0, 1), (0, 0), (1, 0), (2, 0), and (2, 1) bands of [21.5]0+ – X0+ and (0, 0) of [23.3]1 – X0+ transitions observed and analyzed. • The lifetimes of most observed vibronic bands were measured. The laser-induced fluorescence (LIF) excitation spectra of WO molecule have been recorded in the energy range of 18,900–23,500 cm−1 using laser ablation of tungsten target and reaction with free jet expansion of oxygen. Totally 63 vibronic transition bands were observed, and 60 bands were grouped into 10 electronic transition progressions, where 8 electronic transition progressions have the X0+ state as the lower state, as well as 2 progressions have the X1 state as the lower state. The electronic transition systems [21.5]0+–X0+ and [23.3]1–X0+ were newly identified by LIF spectroscopy. The molecular constants, including rotational constant, vibrational frequency, vibrational anharmonic constant, in the electronic excited states were obtained through rotational analysis of the spectra. In addition, the fluorescence lifetimes of the vibronic states were measured under the collision-free condition by exponentially fitting the fluorescence decay. [ABSTRACT FROM AUTHOR]

• MgH was made in a laser-ablation molecular jet. • Highly excited states were studied with single UV photons and two-photon techniques. • First observation of C 2 Π state with laser techniques. • 1 2 Δ state was observed and fit; had been misassigned as D 2 Σ - in 1937. • Lifetimes of some A 2 Π levels were measured. We present the results of laser-ablation molecular jet experiments on the high-lying C 2 Π and 1 2 Δ electronic states of MgH, obtained via laser-induced fluorescence with frequency-doubled pulsed laser beams and with a visible-visible double resonance technique. The C 2 Π state is examined for the first time in nearly 50 years. The 1 2 Δ state was last reported in 1937, when it was misassigned as the D 2 Σ - state. These two states are fit with a modern standard Hamiltonian. Finally, measurements of the lifetime of the F 2 J = 1.5 f level in the v = 0 A 2 Π state are reported; lifetimes of levels of the C 2 Π state were very short (less than the 10 ns lower limit available in our experiment). [ABSTRACT FROM AUTHOR]

Karanjin, a furanoflavonol from Pongamia pinnata L is used in agricultural practices for its pesticidal, insecticidal and acaricidal activities. It is commercially available as a bio-pesticide targeting a wide variety of pests. The present study was intended to evaluate the biochemical interactions of karanjin with bovine serum albumin (BSA) and study its toxicological effects on mammalian and bacterial cell lines. Karanjin bound to BSA at a single site with a dissociation constant of 19.7 μM. Evaluation of BSA-karanjin interactions at three different temperatures indicated the involvement of static mode of quenching. Binding experiments in the presence of warfarin and computational docking analysis indicated that karanjin bound closer to the warfarin binding site located in the Subdomain IIA of BSA. Using Förster resonance energy transfer analysis the distance between TRP 213 of BSA and karanjin was found to be 20 Å. Collective results from synchronous fluorescence spectra analysis, differential scanning calorimetry, and circular dichroism analysis indicated that binding of karanjin induced conformational changes in the secondary structure of BSA. Karanjin exhibited low toxicity against human cervical cancer cells and normal mouse fibroblast L929 cells and modestly inhibited the growth of B. subtilis and E. coli cells. The data presented in this study provides insights for understanding the binding interactions of karanjin with BSA and its possible toxicological effects on mammalian cell lines and bacteria. Unlabelled Image [ABSTRACT FROM AUTHOR]

• Waveguide FTMW measurements at room temperature. • Rotational spectrum from 8 to 18 GHz. • Sextic centrifugal distortion constants from cm-wave data. • Good agreement with anharmonic force field calculations. We have taken advantage of the high resolution and sensitivity of an 8–18 GHz waveguide FTMW spectrometer in order to measure over 150 new rotational transitions in the ground state of fluorobenzene. Most of these transitions are for previously not covered selection rules and their quantum number coverage allowed the knowledge of the previous quartic-level Hamiltonian for this molecule to be extended to the complete set of sextic centrifugal distortion constants. Experimental results were confronted with anharmonic quantum chemistry calculations allowing the conclusion that for this relatively rigid molecule computation reproduces experiment in the robust way already taken for granted for quartic centrifugal distortion. A similar finding was possible for the ground state of phenylacetylene, although in that case new measurements were required to determine only one hitherto missing sextic constant. [ABSTRACT FROM AUTHOR]

Graphical abstract The flowchart of the proposed guideline for generating EES from spectral coherence for bearing fault diagnosis: (a) a raw inner race fault signal; (b) frequency spectrum of (a); (c) spectral coherence; (d) the proposed guideline; (e) EES generated from spectral coherence in a spectral frequency band from 1153 Hz to 1581 Hz; (f) EES generated from spectral coherence in a spectral frequency band from 1991 Hz to 2419 Hz; (g) EES generated from spectral coherence in a spectral frequency band from 2874 Hz to 3302 Hz; (h) EES generated from spectral coherence in a spectral frequency band from 4549 Hz to 4977 Hz. Highlights • Spectral coherence lacks of a guideline for its integration over spectral frequency bands. • The L 2/ L 1 ratio is commonly used to characterize the impulsiveness and cyclostationarity of bearing fault signals. • A simple and fast guideline for integrating spectral coherence was proposed. • Generating enhanced/squared envelope spectrum from spectral coherence was realized. • Spectral coherence integrated with the guideline for bearing fault diagnosis was proposed. Abstract Rolling element bearings are widely used in machines to support rotating shafts and their health conditions degrade over time due to harsh working conditions. Once a fault occurs on the surface of either an inner race or an outer race, impacts caused by rollers striking the fault surface excite resonant frequencies of a machine and then repetitive transients are observed in vibration signals collected from the casing of the machine. Spectral correlation and its normalized version, spectral coherence, are a function of spectral frequency and cyclic frequency, and they are able to simultaneously display resonant frequency bands and bearing fault frequencies. Moreover, it has been proved that integrating spectral correlation over an informative spectral frequency band is related to a squared envelope spectrum which is more conveniently used to detect bearing fault frequencies than the direct inspection of the bi-spectra map of spectral correlation/spectral coherence. Therefore, generating enhanced/squared envelope spectra from spectral correlation/spectral coherence is an important step for the use of spectral correlation/spectral coherence for bearing fault diagnosis. However, in the past years, determining informative spectral frequency bands for generating enhanced/squared envelope spectra from spectral correlation/spectral coherence mainly depends on expertise and careful observations from spectral correlation/spectral coherence. In the case of weak bearing fault frequencies and strong interruptions from other cyclic frequencies, it is not easy for users to determine an informative spectral frequency band for generating an enhanced/squared envelope spectrum from spectral correlation/spectral coherence for bearing fault diagnosis. To solve this problem, a simple and fast guideline is proposed in this paper. Laboratorial bearing fault data and industrial railway axle bearing fault data are used to illustrate how the proposed guideline works. Results showed that the proposed guideline is effective in determining informative spectral frequency bands for generating enhanced/squared envelope spectra from spectral coherence for bearing fault diagnosis. Comparisons with the fast Kurtogram and an enhanced squared envelope spectrum generated from integrating spectral coherence over the whole spectral frequency band are conducted to highlight the superiority of the proposed guideline. [ABSTRACT FROM AUTHOR]

Highlights • Risk management, signal processing and econometrics based novel approach for forecasting the risk of disease emergence. • We propose risk quantification using the Value at Risk criterion. • Multivariate Singular Spectrum Analysis is combined with Quantile Regression (MSSA-QR) in a two staged model. • The MSSA-QR model exceeds in forecasting worst case scenarios for less common waterborne diseases. • Forecasting of more common diseases requires the inclusion of socio-economic and environmental indicators. Abstract This paper takes a novel approach for forecasting the risk of disease emergence by combining risk management, signal processing and econometrics to develop a new forecasting approach. We propose quantifying risk using the Value at Risk criterion and then propose a two staged model based on Multivariate Singular Spectrum Analysis and Quantile Regression (MSSA-QR model). The proposed risk measure (PLVaR) and forecasting model (MSSA-QR) is used to forecast the worst cases of waterborne disease outbreaks in 22 European and North American countries based on socio-economic and environmental indicators. The results show that the proposed method perfectly forecasts the worst case scenario for less common waterborne diseases whilst the forecasting of more common diseases requires more socio-economic and environmental indicators. [ABSTRACT FROM AUTHOR]

Highlights • HARTSS describes taxonomy, mineralogy, & meteorite analogs of 92 Hungaria asteroids. • Mineralogically diverse S-types dominate (~71%) the Hungaria background population. • Taxonomy, albedos, and spectral properties indicate a homogeneous Hungaria family. • The Hungaria family parent body was likely consistent in composition with aubrites. Abstract Spectral observations of asteroid family members provide valuable information regarding parent body interiors, the origin and source regions of near-Earth asteroids, and the link between meteorites and their parent bodies. Asteroids of the Hungaria family represent some of the closest samples to the Earth from a collisional family (∼1.94 AU), permitting observations of smaller family fragments than accessible for Main Belt families. We have carried out a ground-based observational campaign entitled Hungaria Asteroid Region Telescopic Spectral Survey (HARTSS) to record reflectance spectra of these preserved samples from the inner-most regions of the primordial asteroid belt. During HARTSS phase one (Lucas et al. (2017). Icarus 291, 268–287) we found that ∼80% of the background population is comprised of stony S-complex asteroids that exhibit considerable spectral and mineralogical diversity. In HARTSS phase two, we turn our attention to family members to determine if the Hungaria collisional family is compositionally homogeneous or heterogeneous. We use taxonomic classification, geometric albedo (p v) estimates, and near-infrared (NIR) spectral properties to infer the composition of the family. During phase two of HARTSS we acquired NIR spectra of 50 new Hungarias (19 family; 31 background) with the SpeX spectrograph at NASA's Infrared Telescope Facility (IRTF) and with the NICS spectrograph at the Telescopio Nazionale Galileo (TNG). We analyzed X-type spectra for NIR color indices (0.85- J; J - K), and a subtle ∼0.9 µm absorption feature that may be attributed to Fe-poor orthopyroxene ± the sulfide mineral oldhamite. Surviving fragments of an asteroid collisional family typically exhibit similar taxonomies, albedos, and spectral properties. Spectral analysis of Hungaria family X-types and independently calculated WISE albedos for family members (average p v = 0.403; n = 192) is consistent with this scenario. Furthermore, about one-fourth of the background population exhibit similar spectral properties and albedos to family X-types. Spectral observations of 92 Hungaria region asteroids acquired during both phases of HARTSS uncover a compositionally-heterogeneous background population—including two rare olivine-dominated A-types and one apparent D-type interloper—and spectral homogeneity down to ∼2 km for collisional family members. Taxonomy, albedos, and spectral properties indicate that the Hungaria family progenitor was an igneous body that formed under reduced conditions, and was likely consistent in composition with the enstatite achondrite (i.e., aubrite) meteorite group. [ABSTRACT FROM AUTHOR]

Highlights • We confirm 21 olivine-dominated spectral A-type asteroids in the main belt. • We determine 0.16% of the main belt is A-type. • The distribution of A-types as a function of semi-major axis is relatively flat. • We reaffirm there is no significant undiscovered A-type material down to −2 km. • We find no statistically significant relationship with A-types and asteroid families. Abstract Differentiated asteroids are rare in the main asteroid belt despite evidence for ∼ 100 distinct differentiated bodies in the meteorite record. We have sought to understand why so few main-belt asteroids differentiated and where those differentiated bodies or fragments reside. Using the Sloan Digital Sky Survey (SDSS) to search for a needle in a haystack we identify spectral A-type asteroid candidates, olivine-dominated asteroids that may represent mantle material of differentiated bodies. We have performed a near-infrared spectral survey with SpeX on the NASA IRTF and FIRE on the Magellan Telescope. We report results from having doubled the number of known A-type asteroids. We deduce a new estimate for the overall abundance and distribution of this class of olivine-dominated asteroids. We find A-type asteroids account for less than 0.16% of all main-belt objects larger than 2 km and estimate there are a total of ∼ 600 A-type asteroids above that size. They are found rather evenly distributed throughout the main belt, are even detected at the distance of the Cybele region, and have no statistically significant concentration in any asteroid family. We conclude the most likely implication is the few fragments of olivine-dominated material in the main belt did not form locally, but instead were implanted as collisional fragments of bodies that formed elsewhere. [ABSTRACT FROM AUTHOR]

Abstract In this study, Cadmium Sulphide (CdS) thin films are deposited at different deposition times on glass substrate by chemical bath deposition technique. The FESEM images indicated the formation of spherical nano-grains in such a way that with increasing the deposition time the grain diameters are decreased from about 100 to 60 nm. The XRD patterns showed all layers have cubic phase along (111) direction, and as the deposition time increased the crystallinity of the layers are gradually degraded, consistent with the Raman spectra. Analysis of the optical properties revealed that band gap of the films are gradually increased from 2.41 to 2.47 eV, due to defect-related band tail width variations; based on I-V measurements and PL spectra analysis. Highlights • CdS thin films were grown by CBD method at different "deposition time durations". • UV-Vis. spectra revealed a relatively high transmittance (>75%) and low absorbance in visible and near IR spectral range. • XRD patterns showed the formation of "single cubic phase along (111) direction" without annealing process. • PL spectra showed the presence of V S band tail states, as the main source of electrical conductivity in this material. [ABSTRACT FROM AUTHOR]

Highlights • Full-scale identification of the wave forces on a floating bridge is presented. • The force estimation is driven by wave and acceleration data in two approaches. • The spectral density of the obtained force estimates are compared. Abstract The dynamic behaviour of long-span bridges is governed by stochastic loads from typically ambient excitation sources. In real life, these loads cannot be measured directly at full scale. However, inverse methods can be utilised to identify these unknown forces using response measurements together with a numerical model of the relevant structure. This paper presents a case study of full-scale identification of the wave forces on the Bgsøysund bridge, a long-span pontoon bridge that has been monitored since 2013. First, a numerical model of the structure is formed, resulting in a reduced-order state-space model that takes into account the frequency-dependent hydrodynamic mass and damping from the fluid, based on fitting of rational transfer functions. Using acceleration data of the structure measured during several events of moderate and strong seas, the wave forces are identified using stochastic-deterministic methods for combined state and input estimation. In addition, a separate frequency-domain assessment of the wave forces is performed, in which the spectral density of the first-order wave forces is constructed from an estimated directional wave field model driven by wave elevation data. When compared in the frequency domain, the force estimates from the two approaches are of comparable magnitude. However, uncertainties in the assumptions and models behind the force estimates from the two approaches still play a significant role. [ABSTRACT FROM AUTHOR]

Abstract A soil carbon assessment was performed comparing agricultural cropping systems with natural vegetation along a sampling transect spanning different agro-ecologies on the eastern foot slopes of Mount Kenya in Embu county, 125 km from Nairobi, Kenya. The aim was to determine differences in soil carbon stocks and carbon recalcitrance and relate these to soil textural class, altitude, climatic parameters and land use. Soils from main agricultural systems as tea, coffee and maize-based intercropping, as well as from natural vegetation cover were sampled in triplicates, in five layers from 0 to 30 cm in depth and processed for total carbon analysis. The whole soil samples were also analysed using Laser-Induced Fluorescence Spectroscopy (LIFS) to assess carbon humification. Prototype portable equipment intended for future in situ analysis was used in the lab to ascertain the structure of the most recalcitrant and stable carbon present in different agro-ecosystems. In addition, Near Infrared Spectroscopy (NIRS) was tested for the quantitative analysis of soil carbon, showing that it is a reproducible and low-cost method that provided satisfactory results under the processing conditions of the samples. Results showed wide variation in the level and quality of carbon stored in the soils, depending on soil texture, land use, elevation, climate, agricultural practices and land use history. Considering the heterogeneous nature of sampled soils and the performance of NIRS and LIFS, these results can be used as a basis for the development of fully portable systems able to provide rapid, clean and potentially cost-effective relevant information for soil management. Highlights • Soil carbon assessment was performed along different agro-ecologies from Nairobi, Kenya. • Soil carbon was assessed in function of land use changes. • Soil carbon stocks and stability were assessed using different spectroscopic methods. • Soil humification index as a quality/recalcitrance indicator was estimated. • The high potential of NIRS for soil carbon quantification was shown. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Herein, we have explored the conformational alterations of hemoglobin (Hb) in presence of a cleavable gemini surfactant (C16-C4O2-C16). The concerned surfactant was found to induce significant structural perturbations in Hb. UV–vis spectroscopy, steady-state/time-resolved fluorescence, and other utilized techniques have authenticated the complexation of Hb with the gemini surfactant. CD has demonstrated the alterations in secondary structural elements (α-helicity, β-sheet, β-turn, and random coil) of Hb upon C16-C4O2-C16 addition. Atomic force microscopy (AFM) has revealed the existence of unique star-shaped gemini surfactant microstructures aligned to Hb in a necklace pattern. The 1H NMR peak broadening and lower delta values hint at the binding of the concerned gemini surfactant to Hb. Molecular docking and DFT calculations have further substantiated the Hb-gemini complex formation and the involvement of electrostatic/hydrophobic forces therein. In future, these results might pave-the-way to construct self-assembled, sustainable, and green surfactant-protein mixtures for their end-use in industrial, engineering, biomedical, drug delivery, gene transfection, and other relevant excipient formulations. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Hypothesis Stratification or self-segregation of multicomponent particle mixtures during drying is an important phenomenon to understand for the development of single-step deposition processes for complex coatings. We hypothesize that varying the ratio of particle Peclet numbers will lead to different types of stratification behavior. Experiments Binary colloidal films of polystyrene and silica were prepared by evaporative film formation, and stratification of nanoparticles of different size ratio (7.7–1.2) was studied using microbeam small-angle X-ray scattering (SAXS). Findings SAXS spectra showed noticeable variations at different film depths, consistent with stratification. These results are quantified to obtain vertical composition profiles. We observe "sandwich"-type layered structures at different nanoparticle size ratios, which to our knowledge have not been previously observed experimentally or predicted by theory. For example, for films of larger particle size ratios (7.7–4.8), large particles are enriched at the film top and bottom, leading to a large-small-large or "LSL" behavior; while within films of smaller particle size ratio (2.2–1.2), small particles are enriched at the top and bottom of the film (small-large-small or "SLS" structures). The enrichment of particles at the top persists over several hundred particle layers and is not just a single monolayer pinned to the upper surface. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract In the present work, properties of the interlayer breathing modes in twisted MoS 2 samples with different structures are carefully examined. The distribution of peak position of the breathing modes is mainly dependent on overall layer numbers, and is only slightly affected by specific structure of the sample. Linear chain model calculation shows quantitatively a markedly decrease in interlayer force on the twisted interface, and slight difference in Raman frequency may mean considerable difference in interlayer force. When one or both of the component layers get too thick, no new breathing modes can be found, indicating that rigidity of the component may affect the coupling efficiency. Our work demonstrates that low-frequency Raman spectroscopy can act as an effective indirect strategy for the detection of interlayer interaction, which is a good complement to existing methods such as AFM technologies. [ABSTRACT FROM AUTHOR]

Abstract Recombinant antibodies have emerged over the last few decades as the fastest growing class of therapeutic proteins for autoimmune diseases. Post-translation modifications of antibodies produced by human cell lines are highly consistent with those existing in natural human proteins and this is a major advantage of utilizing these cell lines. Cinorra is a biosimilar form of the antibody Adalimumab, which is an antagonist of TNF-α used for the treatment of autoimmune diseases. Adalimumab and Cinorra were produced by stable expression from CHO cells. The aim of this study was to select HEK cells as a host for producing Adalimumab to reveal whether the antibody produced by this human-derived cell line has similar characterization to Cinorra. Adalimumab was transiently produced in HEK-293T cells, characterized and analyzed for its properties. Circular dichroism spectroscopy confirmed a strong structural similarity of the expressed antibody with Cinorra. Likewise its binding activity and kinetic affinity to TNF-α (EC 50 = 416.5 ng/ml, KD = 3.89 E-10 M,) were highly similar to that of Cinorra (EC 50 = 421.2 ng/ml and KD = 3.34 E-10 M,). Additionally there was near identical neutralization of TNF-α-mediated cellular cytotoxicity (IC 50 of the expressed = 4.93 nM; IC 50 of Cinorra = 4.5 nM). Results indicate that Adalimumab produced by HEK-293T cells possesses a similarly efficient function and biological activity to Cinorra. Consequently, human-derived host cells with human post-translational modifications might potentially provide a basis for the development of Adalimumab with pharmaceutical properties for research and therapeutic use. Highlights • Cinorra is a new biosimillar form of the antibody Adalimumab developed using CHO cell lines. • Adalimumab produced by HEK-293T cells has a similar structure to Cinorra. • Adalimumab produced by HEK-293T cells has a similar binding activity and affinity to Cinorra. • Adalimumab produced by HEK-293T cells has analogous biological activity to Cinorra. • Human-derived cells with human PTMs are a preferred option for developing therapeutic antibodies. [ABSTRACT FROM AUTHOR]

Abstract Background Cardiovascular disease (CVD) is associated with impairments in microvascular responsiveness. Therefore, reliably assessing microvascular function is clinically relevant. Thus, this study aimed to examine the reliability of the near-infrared spectroscopy (NIRS)-derived oxygen saturation (StO 2) reperfusion slope, a measure of microvascular responsiveness, to four different vascular occlusion tests (VOT) of different durations in young and older participants. Methods Eight healthy young (29 ± 5 yr) and seven older (67 ± 4 yr) men participated in four NIRS combined with VOT (NIRS-VOT; 30 s, 1, 3, and 5 min) in the leg microvasculature on two visits separated by 1–2 weeks. Vascular responsiveness was determined by the StO 2 reperfusion slope. The coefficient of variation (CV), repeatability, reliability (ICC), and the limits of agreement (LOA) were calculated for the NIRS-derived reperfusion slopes for each occlusion duration and visit. Results CV for the StO 2 reperfusion slope following 30 s, 1, 3 and 5 min of occlusion were 33 ± 29%, 19 ± 21%, 14 ± 12%, and 12 ± 10%, respectively. Repeatability values following 30 s, 1, 3 and 5 min occlusions were 20%, 1%, 4% and 21%, respectively. The ICC for the StO 2 reperfusion slopes for each occlusion duration were 0.29, 0.42, 0.84, and 0.88 following 30 s, 1, 3 and 5 min of occlusion, respectively. LOA values between visit 1 and 2 for occlusions were not different from zero. There were no age-related differences for all variables of the study. Conclusion NIRS-derived StO 2 reperfusion slope, has good reliability across a range of occlusion durations with the strongest reliability during longer occlusion durations. Highlights • NIRS-VOT technique has been widely used for assessment of vascular responsiveness within the microvasculature. • NIRS-VOT is a reliable and repeatable technique for intra- and interday assessments of microvascular function. • NIRS-derived StO 2 reperfusion slope, has good reliability across a range of occlusion durations in young and old individuals. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • An in vivo MRS method for biological tissues is proposed. • Resolution enhanced J -resolved spectra can be obtained from in vivo samples. • The use of optimal echo sampling can improve SNR. • The spectral quality is not influenced by voxel size variation. Abstract Magnetic resonance spectroscopy (MRS) provides a noninvasive tool for metabolite characterization of in vivo biological samples. Conventional MRS measurements on biological samples generally suffer from field inhomogeneity caused by intrinsic magnetic susceptibility variations inside samples. Compared to one-dimensional MRS, two-dimensional (2D) J -resolved spectroscopy enables resolving J couplings along one of the spectral dimension and benefits to metabolite identification and analyses. Intermolecular double-quantum coherences (iDQC) has been proven to be insensitive to magnetic field inhomogeneity, herein we propose a MRS approach based on iDQC evolution and optimal echo sampling scheme to achieve high-resolution 2D J -resolved measurements on biological samples. The applicability of the proposed method is evaluated with experiments on an ex vivo pig brain tissue and an in vivo rat brain tissue. Compared to conventional MRS method which is sensitive to field inhomogeneity inside investigated biological tissues, the proposed method holds immunity to this field inhomogeneity and the quality of resulting spectra may not be influenced by localized voxel size variation. The signal to noise ratio enhancement of the proposed method benefitting from the optimal echo signal sampling is verified with a solution experiment. The new method provides a promising way for high-resolution MRS measurements on biological samples. In combination with fast acquisition strategy, it may find some promising biomedical applications. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Epi -polygodial is isolated and presents Antitrypanosomal activity. • Epi -polygodial is incorporated in biointerface models. • Epi -polygodial changed the thermodynamic and structural properties of DPPE monolayers. • Changes in the monolayers can be associated to the interaction with membranes. Abstract Epi -polygodial, a drimane sesquiterpene was isolated from Drimys brasiliensis (Winteraceae). This compound demonstrated high parasite selectivity towards Trypanosoma cruzi trypomastigotes (IC 50 = 5.01 μM) with a selectivity index higher than 40. These results were correlated with the effects observed when this compound was incorporated in cellular membrane models of protozoans, represented by Langmuir monolayers of dipalmitoylphosphoethanolamine (DPPE). Surface pressure-area isotherms showed that epi -polygodial expands DPPE monolayers at higher areas and condenses them at lower areas, which was attributed to the preferential interaction with the polar heads of the lipid. This mechanism of action could be corroborated with Polarization-Modulation Reflection-Absorption Spectroscopy and Brewster Angle Microscopy. These results pointed to the fact that the interaction of epi -polygodial with DPPE monolayers at the air-water interface affects the physical chemical properties of the mixed film, which may be important to comprehend the interaction of this drug with cellular membranes at the molecular level. [ABSTRACT FROM AUTHOR]

Abstract We introduce a numerical framework that enables unprecedented direct numerical studies of the electropermeabilization effects of a cell aggregate at the meso-scale. Our simulations qualitatively replicate the shadowing effect observed in experiments and reproduce the time evolution of the impedance of the cell sample in agreement with the trends observed in experiments. This approach sets the scene for performing homogenization studies for understanding the effect of tissue environment on the efficiency of electropermeabilization. We employ a forest of Octree grids along with a Voronoi mesh in a parallel environment that exhibits excellent scalability. We exploit the electric interactions between the cells through a nonlinear phenomenological model that is generalized to account for the permeability of the cell membranes. We use the Voronoi Interface Method (VIM) to accurately capture the sharp jump in the electric potential on the cell boundaries. The case study simulation covers a volume of (1 mm) 3 with more than 27 , 000 well-resolved cells with a heterogeneous mix of morphologies that are randomly distributed throughout a spheroid region. Highlights • An efficient framework for direct simulations of the mesoscale cell aggregates (tissue scale) is proposed. • The model is simulated on a Voronoi mesh and in a parallel environment that is developed in the context of level-set method. • The proposed framework imposes the sharp boundary conditions on the cell membranes using the Voronoi Interface Method (VIM). • For the first time, multi-scale simulation of cell aggregate electroporation at the tissue scale has become possible. [ABSTRACT FROM AUTHOR]