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The effect of niobium ion implantation on the surface and scratch properties of a WC-5wt.%Ni cold sprayed coating was investigated with accelerating energies of 60 and 170 keV and fluences of 5 × 1016 and 8 × 1016 ions cm−2, respectively. High-resolution Rutherford backscattering spectroscopy spectra revealed that Ni-Nb and WC-Nb amorphous layers had likely formed. Using ion implantation parameters of 60 keV with a fluence of 8 × 1016 ions cm-2 (coating 608-NB), higher Nb peak intensities were found. Oxide formation in the form of NbO, NbO2, and Nb2O5 was detected with high-resolution x-ray photoelectron spectroscopy spectra analyses on the 608-NB coating, in conjunction with the intermetallic, thereby having the best coating properties: higher hardness, low roughness, and scratch properties compared to the other ion-doped samples. The failure mechanisms of all the coatings were found to be similar, showing angular cracks, cone cracking, and primary delamination. [ABSTRACT FROM AUTHOR]

In this study, we prepared and characterized lampblack of olive oil for application in supercapacitors. The lampblack was prepared by the simple technique of flame-soot method. The lampblack samples characterized by using X-ray Diffraction (XRD), Raman spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), N2 adsorption-desorption isotherms, Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray Spectroscopy (EDS) revealed that they contain mostly amorphous nanosized carbon particles with oxygenated functional groups and the carbon content in the lampblack was 92.6%. The surface area of the lampblack carbon calculated from the Brunauer-Emmett-Teller (BET) method was found to be about 302.7 m²g-1 with an average pore size of 1.69 nm obtained from the Density Functional Theory (DFT) analysis. Lampblack carbon samples were used to prepare supercapacitor electrodes. Electrochemical properties of the electrodes were investigated in 6M aqueous KOH by Cyclic Voltammetry (CV), Galvanostatic Charge Discharge (GCD), and Electrochemical Impedance Spectroscopy (EIS) techniques. The specific capacitance of the electrode obtained from the GCD test was 70.36 Fg-1 at the current density of 1 Ag-1 with a low Equivalent Series Resistance (ESR) value of 0.81 Ω. [ABSTRACT FROM AUTHOR]

In this present work, Fe2O3 nanoparticles doped with different concentrations of aluminium oxide (Al2O3) (5%, 10%, and 20%) were synthesized by the modified co-precipitation method, and samples were calcined at 600 oC for a fixed duration 2 hours. The calcined samples were examined through X-ray diffraction (XRD) techniques and results reveal that rhombohedral crystalline structures were confirmed for all calcined samples and the crystallite size of the particle increased from 42.2 nm to 60.5 nm i.e. crystallite size increases with increase of in dopant concentration alumina in Fe2Al2O6-δ samples. The infrared spectroscopic results reveal that, as usual, peaks of hydroxyl group vibrations were found in band formation at about 3000 cm-1, 1650 cm-1 and the sharp peaks at 610, 614, and 617 cm-1 were attributed to O-Fe-O molecules vibrations whereas, 533 cm-1 were attributed by O-Al-O molecules vibrations. The optical band gap was calculated via tauc plot and calculated values show an inverse trend of 2.19 to 2.15 eV with an increase in dopant concentration alumina. Vibrating sample magnetometer (VSM) were used to analyze the magnetic characteristics of calcined samples and the results reveal that saturation magnetization is highest for dopant alumina 10% concentration (Ms = 50.6×10-2 emu/g) and coercivity is highest for dopant alumina 5% concentration (Hc = 875.38Oe) respectively among all the calcined samples. [ABSTRACT FROM AUTHOR]

AbstractFour new alkaloids, arecatines A–D (1–4), were isolated from the peels of Areca catechu. Compound 1 is an unusual piperidine-pyridine hybrid alkaloid, whereas compounds 2–4 feature bis-piperidine alkaloids. Their structures were elucidated by UV, IR, HRESIMS, and NMR spectra analysis. The molecular docking analysis indicated that compound 3 exhibited the best binding affinity with the GABAA receptor, indicating its potential anti-epilepsy activity. [ABSTRACT FROM AUTHOR]

Purpose: To analyze the characteristics of PEEK rods retrieved in vivo, specifically their wear and deformation, biodegradability, histocompatibility, and mechanical properties. Method: Six PEEK rods were retrieved from revision surgeries along with periprosthetic tissue. The retrieved PEEK rods were evaluated for surface damage and internal changes using Micro-CT, while light and electron microscopy were utilized to determine any histological changes in periprosthetic tissues. Patient history was gathered from medical records. Two intact and retrieved PEEK rods were used for fatigue testing analysis by sinusoidal load to the spinal construct. Results: All implants showed evidence of plastic deformation around the screw-rod interface, while the inner structure of PEEK rods appeared unchanged with no visible voids or cracks. Examining images captured through light and electron microscopy indicated that phagocytosis of macrophages around PEEK rods was less severe in comparison to the screw-rod interface. The results of an energy spectrum analysis suggested that the distribution of tissue elements around PEEK rods did not differ significantly from normal tissue. During fatigue testing, it was found that the retrieved PEEK rods cracked after 1.36 million tests, whereas the intact PEEK rods completed 5 million fatigue tests without any failure. Conclusion: PEEK rods demonstrate satisfactory biocompatibility, corrosion resistance, chemical stability, and mechanical properties. Nevertheless, it is observed that the indentation at the junction between the nut and the rod exhibits relatively weak strength, making it susceptible to breakage. As a precautionary measure, it is recommended to secure the nut with a counter wrench, applying the preset torque to prevent overtightening. [ABSTRACT FROM AUTHOR]

Background: Lead is one of the most nonessential toxic heavy metal agents found in automotive garages. The occupational exposure of garage workers to lead commonly poses acute and chronic health risks that can be prevented. In Ethiopia, there have been limited studies on lead exposure among garage workers, who overemphasize exposure to lead. This study aimed to assess occupational blood lead levels and associated factors in garage workers using a cross-sectional comparative design. Methods: A comparative cross-sectional study design was used to compare the occupational blood lead levels of 36 randomly selected garage workers and 34 office workers who were matched by age and sex. Blood specimens were collected by trained medical laboratory experts. The collected blood samples were tested in a certified laboratory using a microwave plasma atomic emission spectrometry (MP-AES) device at a wavelength of 405.78 nm. Excel and SPSS Version 26 were used for data management and analysis, respectively. Results: The mean (SD) age of the exposed group was 39.0 (7.5) years, whereas the mean age of the unexposed group was 38.0 (6.1) years. The occupational mean (SD) blood-lead-level in the exposed groups was 29.7 (12.2) µg/dl, compared to 14.8 (9.9) µg/dl among the unexposed groups. The mean blood-lead level among the exposed workers was significantly different from that among the unexposed workers (P < 0.01). Of all the study participants, only 22.2% of the exposed groups had blood lead levels higher than the World Health Organization's recommended limit of 40 µg/dl. The main significant predictors of occupational blood-lead-level exposure among workers were extra working hours, service years, and having a previous (prior) employment history in a garage. The occupations of the two groups did not significantly differ in terms of blood-lead levels (p > 0.05). Conclusions: The BLL of the Garage workers was significantly greater than that of the Non-Garage workers. Hence, it is advised that garage management should encourage workers to use exposure prevention methods, such as washing their hands before eating and taking showers after the completion of work, by providing regular occupational safety training. [ABSTRACT FROM AUTHOR]

Background: Dental pathogens play a crucial role in oral health issues, including tooth decay, gum disease, and oral infections, and recent research suggests a link between these pathogens and oral cancer initiation and progression. Innovative therapeutic approaches are needed due to antibiotic resistance concerns and treatment limitations. Methods: We synthesized and analyzed piperine-coated zinc oxide nanoparticles (ZnO-PIP NPs) using UV spectroscopy, SEM, XRD, FTIR, and EDAX. Antioxidant and antimicrobial effectiveness were evaluated through DPPH, ABTS, and MIC assays, while the anticancer properties were assessed on KB oral squamous carcinoma cells. Results: ZnO-PIP NPs exhibited significant antioxidant activity and a MIC of 50 µg/mL against dental pathogens, indicating strong antimicrobial properties. Interaction analysis revealed high binding affinity with dental pathogens. ZnO-PIP NPs showed dose-dependent anticancer activity on KB cells, upregulating apoptotic genes BCL2, BAX, and P53. Conclusions: This approach offers a multifaceted solution to combatting both oral infections and cancer, showcasing their potential for significant advancement in oral healthcare. It is essential to acknowledge potential limitations and challenges associated with the use of ZnO NPs in clinical applications. These may include concerns regarding nanoparticle toxicity, biocompatibility, and long-term safety. Further research and rigorous testing are warranted to address these issues and ensure the safe and effective translation of ZnO-PIP NPs into clinical practice. [ABSTRACT FROM AUTHOR]

Objective: To introduce MexOMICS, a Mexican Consortium focused on establishing electronic databases to collect, cross-reference, and share healthrelated and omics data on the Mexican population. Methods: Since 2019, the MexOMICS Consortium has established three electronic-based registries: the Mexican Twin Registry (TwinsMX), Mexican Lupus Registry (LupusRGMX), and the Mexican Parkinson's Research Network (MEX-PD), designed and implemented using the Research Electronic Data Capture web-based application. Participants were enrolled through voluntary participation and on-site engagement with medical specialists. We also acquired DNA samples and Magnetic Resonance Imaging scans in subsets of participants. Results: The registries have successfully enrolled a large number of participants from a variety of regions within Mexico: TwinsMX (n = 2,915), LupusRGMX (n = 1,761) and MEX-PD (n = 750). In addition to sociodemographic, psychosocial, and clinical data, MexOMICS has collected DNA samples to study the genetic biomarkers across the three registries. Cognitive function has been assessed with the Montreal Cognitive Assessment in a subset of 376 MEX-PD participants. Furthermore, a subset of 267 twins have participated in cognitive evaluations with the Creyos platform and in MRI sessions acquiring structural, functional, and spectroscopy brain imaging; comparable evaluations are planned for LupusRGMX and MEX-PD. Conclusions: The MexOMICS registries offer a valuable repository of information concerning the potential interplay of genetic and environmental factors in health conditions among the Mexican population. [ABSTRACT FROM AUTHOR]

This study aims to encapsulate Cosmos caudatus K. leaf extract in sodium alginate crosslinked with calcium chloride (CaCl2) as coating materials through freeze-drying. Antioxidant assays were performed to evaluate the applicability of the microcapsules as antidiabetic medicines. Their characteristics, antioxidant activity, and encapsulation efficiency (EE) were also examined. Results indicated that the concentration of sodium alginate and pH influenced the manufacturing process of the microcapsules. The highest EE was obtained at pH 6 and alginate concentration of 2% (w/v). The IC50 for the antioxidant activity of the microcapsules was 139.96 ± 1.094 µg/mL. Scanning electron microscopy confirmed the presence of irregular and spherical structures on the surface. Fourier transform infrared spectra showed new absorption bands at 1593.10 and 1427.59 cm-1, demexistening the existence of stretching vibrations of COO-. Absorption at 1024.14 cm-1 demonstrated C-C and C-O bond stretching vibrations in the sodium alginate--CaCl2 crosslinks. Fourier transform infrared spectrum analyses indicated that sodium alginate and CaCl2 formed chemical bonds, enabling microencapsulation. This study discovered that microencapsulation is a highly prospective and adaptable strategy for enhancing the medicinal use of plant extract. [ABSTRACT FROM AUTHOR]

This paper presents a generalized vibration-based multiple breathing crack localization technique in beams with an unknown number of cracks based on Singular Spectrum Analysis (SSA). Localization of multiple breathing cracks is a highly challenging inverse problem, as all these breathing cracks (more than two) might be in a similar state (either opening or closing state) at any particular time instant or in contrasting states (while some breathing cracks are opening, others in closing state) during vibration. The level of nonlinearity of vibration response is strongly dependent not only on each crack size, and location but also on the application of driving force along the cracked beam. The concept of varied input frequency excitation sources is employed in the present work for multiple breathing crack identification over the tedious traditional approach of varying input force application positions. The major advantage of using singular spectrum analysis in the present work is that it can reliably isolate and extract the very low-amplitude nonlinear sensitive components (super harmonics and intermodulation) being buried in the total response based on the pairwise eigenvalue property of harmonic components. Investigations have been carried out by varying the number, spatial locations, and also intensities of the breathing cracks. Sensitivities associated with measurement noise and also with limited sensors are also investigated. The results of both numerical and experimental investigations carried out in this paper concluded that the proposed SSA can effectively localize closely spaced or sparsely spaced (i.e.,, spatially far apart) multiple cracks in the beam. The proposed SSA approach is data-driven, works with limited sensors, and does not need reference healthy state measurements. [ABSTRACT FROM AUTHOR]

It is around a century that sample autocorrelation function has been introduced and used as a standard tool in time series analysis. A vast literature can be found on the statistical properties of the sample autocorrelation function. However, it has been highlighted recently that the sum of the sample autocorrelation function over the lags 1 to T − 1 is −0.5 for all time series of length T. This property produces a big concern for the cases in which all available sample autocorrelations are used in the inference. This paper provides two new alternative for estimating the autocorrelation function. These estimators come from the idea of singular spectrum analysis which is a non-parametric technique for time series analysis. The paper utilizes a simulation study to illustrate the performance of the new approach. The results suggest that further improvement to the sample autocorrelation is possible and the new methods provide an attractive alternative to the classical approach. [ABSTRACT FROM AUTHOR]

Flavonol and flavonoid compounds are important natural compounds with various biomedical activities. Therefore, it is of great significance to develop a strategy for the specific extraction of flavonol and flavonoid compounds. Quercetin is a well-studied flavonoid possessing many health benefits. This compound is a versatile antioxidant known to possess protective abilities against body tissue injury induced by pathological situations and various drug toxicities. Although quercetin is widely distributed in many plants, its content generally is not very high. Therefore, the specific extraction of quercetin as well as other flavonol and flavonoid compounds has profound significance. In this work, the quercetin molecularly imprinting polymer (QMIP) was successfully prepared, in which a typical flavonol quercetin was selected as the template molecule. QMIP was synthesized by performing the surface molecular imprinting technology on the surface of NH2-MIL-101(Fe). Our study results showed that QMIP exhibited quick binding kinetic behavior, a high adsorption capacity (57.04 mg/g), and the specific recognition ability toward quercetin compared with structurally distinct compounds (selective factor > 2). The specific adsorption ability of quercetin by QMIP was further explained using computation simulation that molecules with non-planar 3D conformations hardly entered the molecularly imprinted cavities on QMIP. Finally, QMIP was successfully used for the specific extraction of quercetin and five other flavonol and flavonoid compounds in the crude extracts from Sapium sebiferum. This study proposes a new strategy to synthesize the molecularly imprinted polymer based on a single template for enriching and loading a certain class of active ingredients with similar core structures from variable botanicals. [ABSTRACT FROM AUTHOR]

Aims: Liquid biopsy (LBx)‐based next‐generation sequencing (NGS) of circulating tumour DNA (ctDNA) can facilitate molecular profiling of haematopoietic neoplasms (HNs), particularly when tissue‐based NGS is infeasible. Methods and Results: We studied HN LBx samples tested with FoundationOne Liquid CDx, FoundationOne Liquid, or FoundationACT between July 2016 and March 2022. We identified 271 samples: 89 non‐Hodgkin lymphoma (NHL), 43 plasma‐cell neoplasm (PCN), 41 histiocytoses, 27 myelodysplastic syndrome (MDS), 25 diffuse large B‐cell lymphoma (DLBCL), 22 myeloproliferative neoplasm (MPN), 14 Hodgkin lymphoma (HL), and 10 acute myeloid leukaemia (AML). Among 73.4% with detectable pathogenic alterations, median maximum somatic allele frequency (MSAF) was 16.6%, with AML (36.2%), MDS (19.7%), and MPN (44.5%) having higher MSAFs than DLBCL (3.9%), NHL (8.4%), HL (1.5%), PCN (2.8%), and histiocytoses (1.8%) (P = 0.001). LBx detected characteristic alterations across HNs, including in TP53, KRAS, MYD88, and BTK in NHLs; TP53, KRAS, NRAS, and BRAF in PCNs; IGH in DLBCL; TP53, ATM, and PDCD1LG2 in HL; BRAF and MAP2K1 in histiocytoses; TP53, SF3B1, DNMT3A, TET2, and ASXL1 in MDS; JAK2 in MPNs; and FLT3, IDH2, and NPM1 in AML. Among 24 samples, the positive percent agreement by LBx was 75.7% for variants present in paired buffy coat, marrow, or tissues. Also, 75.0% of pairs exhibited alterations only present on LBx. These were predominantly subclonal (clonal fraction of 3.8%), reflecting the analytical sensitivity of LBx. Conclusion: These data demonstrate that LBx can detect relevant genomic alterations across HNs, including at low clonal fractions, suggesting a potential clinical utility for identifying residual or emerging therapy‐resistant clones that may be undetectable in site‐specific tissue biopsies. [ABSTRACT FROM AUTHOR]

Future surveys could obtain tighter constraints on the cosmological parameters with the galaxy power spectrum than with the cosmic microwave background. However, the inclusion of multiple overlapping tracers, redshift bins, and more non-linear scales means that generating the necessary ensemble of simulations for model-fitting presents a computational burden. In this work, we combine full-shape fitting of galaxy power spectra, analytical covariance matrix estimates, the massively optimized parameter estimation and data compression (MOPED) method, and the Taylor expansion interpolation of the power spectrum for the first time to constrain the cosmological parameters directly from a state-of-the-art set of galaxy clustering measurements. We find it takes less than a day to compute the analytical covariance while it takes several months to calculate the simulated ones. Combining MOPED with the Taylor expansion interpolation of the power spectrum, we can constrain the cosmological parameters in just a few hours instead of a few days. We also find that even without a priori knowledge of the best-fitting cosmological or galaxy bias parameters, the analytical covariance matrix with the MOPED compression still gives consistent cosmological constraints to within 0.1σ after two iterations. Therefore, the pipeline we have developed here can significantly speed up the analysis for future surveys. [ABSTRACT FROM AUTHOR]

This paper aims to present better physical understanding of flexural wavenumber spectral behaviors of multi-stepped periodic beams by the method of reverberation-ray matrix (MRRM) based on the Timoshenko beam theory. According to the Bloch theorem, the formulation of MRRM is presented and the complex flexural wavenumbers of multi-stepped periodic beams are solved by numerical techniques. The validation of MRRM in analyzing flexural wave behaviors of multi-stepped periodic beams is verified by comparison with the analytical wavenumber spectrum of a homogeneous beam. Numerical examples are provided to illustrate the general wavenumber spectral characteristics of an infinite periodic beam with alternate variation of cross-sections. The effects of the material properties and geometrical parameters of the beam segments are evaluated. The most remarkable finding inspired from the wavenumber spectral curves is that the real wavenumber of the multi-stepped periodic beam does not vary with frequency in the attenuation bands, which indicates that the wavelength of the flexural wave is constant in the attenuation bands. Highlights A multi-stepped periodic beam model with arbitrary finite number of beam segments is established. Complex wavenumber spectrum analysis is performed to reveal the propagation and attenuation behaviors of multi-stepped periodic beams. Similarity and comparative studies on the propagation and attenuation characteristics of beams of a uniform cross-section and of variable cross-sections are carried out to provide better physical understanding. An innovative finding that the wavelength of the flexural wave is constant in the attenuation bands is achieved. [ABSTRACT FROM AUTHOR]

(Multichannel) Singular spectrum analysis is considered as one of the most effective methods for seismic incoherent noise suppression. It utilizes the low-rank feature of seismic signal and regards the noise suppression as a low-rank reconstruction problem. However, in some cases the seismic geophones receive some erratic disturbances and the amplitudes are dramatically larger than other receivers. The presence of this kind of noise, called erratic noise, makes singular spectrum analysis (SSA) reconstruction unstable and has undesirable effects on the final results. We robustify the low-rank reconstruction of seismic data by a reweighted damped SSA (RD-SSA) method. It incorporates the damped SSA, an improved version of SSA, into a reweighted framework. The damping operator is used to weaken the artificial disturbance introduced by the low-rank projection of both erratic and random noise. The central idea of the RD-SSA method is to iteratively approximate the observed data with the quadratic norm for the first iteration and the Tukeys bisquare norm for the rest iterations. The RD-SSA method can suppress seismic incoherent noise and keep the reconstruction process robust to the erratic disturbance. The feasibility of RD-SSA is validated via both synthetic and field data examples. [ABSTRACT FROM AUTHOR]

Laser spectroscopy is a very precise tool in determining atomic structure data. However, in the case of complex spectra, when the individual components of the spectra cannot be separated, precise analysis is hindered by the appearing saturation effect. Sometimes this effect is so large that the spectrum simulation does not provide precise results. In the present work, we present the analysis of the Zeeman spectra of seven praseodymium lines in the range of 566–652 nm, which were recorded using the LIF technique in the presence of the saturation effect. To analyze these spectra, we used a specially dedicated computer program, which allowed for very accurate matching of the simulated spectrum to the recorded experimental shape. As a result of the conducted research, we determined 14 Lande factor values, 3 of which are new. [ABSTRACT FROM AUTHOR]

Mutations in the gene SCAPER (S phase Cyclin A-Associated Protein residing in the Endoplasmic Reticulum) have recently been associated with retinitis pigmentosa (RP) and intellectual disability (ID). In 2011, a possible involvement of SCAPER in human diseases was discovered for the first time due to the identification of a homozygous mutation causing ID in an Iranian family. Later, five studies were published in 2019 that described patients with autosomal recessive syndromic retinitis pigmentosa (arRP) accompanied by ID and attention-deficit/hyperactivity disorder (ADHD). This present study describes three patients from an Arab consanguineous family in Israel with similar clinical features of the SCAPER syndrome. In addition, new manifestations of ocular symptoms, nystagmus, glaucoma, and elevator palsy, were observed. Genetic testing of the patients and both parents via whole-exome sequencing revealed the homozygous mutation c.2023–2A>G in SCAPER. Phenotypic and genotypic descriptions for all available cases described in the literature including our current three cases (37 cases) were carried out, in addition to a bioinformatics analysis for all the genetic variants that was undertaken. Our study confirms and extends the clinical manifestations of SCAPER-related disorders. [ABSTRACT FROM AUTHOR]

Fluidized beds are favored for their high efficiency in material and heat exchange. However, a limited understanding of two-phase flow dynamics leads to the construction of larger equipment and makes precise control of fluidized beds challenging. Since it is challenging to eliminate the impact of signal noise in experiments, which arises from the inconsistency of particles and measurement methods, a square fluidized bed model has been established for numerical analysis of the chaotic characteristics of two-phase flow. The bubble distribution in the fluidized bed was observed more clearly, the bubble behavior was combined with the chaotic parameters, and the two flow states and the chaotic state were analyzed comprehensively. The results show that the bubbles present a regular arrangement parallel to the diagonal in the early stage of bubbling. At the same time, smooth reconstructed attractors are observed. The increase in fluidization wind speed will make the attractors rough until collapse. The bubbling bed experiences bifurcation into chaos as the fluidization wind speed increases, and we can see this process through the pressure signal. The system state cannot be distinguished by correlation dimension or K-entropy alone. Comprehensive consideration of a variety of chaotic features can be used as a method to identify two-phase flow chaotic states. The method used in this paper combines bubble behavior, pressure signal, power spectrum analysis, phase space reconstruction, correlation dimension, and Kolmogorov entropy to distinguish the state of the fluidized bed more accurately. [ABSTRACT FROM AUTHOR]

A set of colour tuning K2Ba(MoO4)2: Dy3+/Eu3+ (KBM: Dy3+/Eu3+) phosphors were fabricated by solid-state method. The phase purity of as-prepared materials was validated by XRD and DRS analyses. The KBM: 0.03Dy3+ sample exhibits two major luminescence lines at 481 and 572 nm when excited by 351 nm light, corresponding to Dy3+ ions' typical transitions of 4F9/2 → 6HJ (J = 15/2, 13/2). By introducing Eu3+ ions into KBM: 0.03Dy3+ phosphor, the ET from Dy3+ to Eu3+ ions arises, leading to colour tuning from green via yellowish green to pink with changing Eu3+ ions' concentration, along with the lowest CCT of KBM: 0.03Dy3+/0.03Eu3+ sample. It can be verified by PLE and PL spectra analysis combined with the decay times of KBM: 0.03Dy3+/yEu3+ samples. The energy transfer mechanism is also expounded. Meanwhile, the emission intensities at 423 K still maintain 72.8% for Dy3+ ions and 91.2% for Eu3+ ions relative to 303 K of the KBM: 0.03Dy3+/0.03Eu3+ sample, displaying its brilliant thermal stability. All these results connote that KBM: Dy3+/Eu3+ phosphors are prospected to be used for the near-UV excited white light-emitting diodes. [ABSTRACT FROM AUTHOR]

The bogie frame, as one of the most critical load-bearing structures of the Electric Multiple Unit (EMU), is responsible for bearing and transmitting various loads from the car body, wheelsets, and its own installation components. With the increasing operating speed of high-speed EMUs, especially when the design and operational speeds exceed 400 km/h, the applicability of current international standards is uncertain. The load spectrum serves as the foundation for structural reliability design and fatigue evaluation. In this paper, the measured loads of the bogie frame of a CR400AF high-speed train on the Beijing–Shanghai high-speed railway are obtained, and the time-domain characteristic of the measured loads is analyzed under different operating conditions. Then, through the Weibull distribution of three parameters, the Weibull parameters at the 450 km/h speed level are fitted, and the maximum load and cumulative frequency under the speed level are derived. Finally, the load spectrum of the bogie frame at the 450 km/h speed level is established, which provides a more realistic load condition for accurately evaluating the fatigue strength of bogie frames at higher speed levels. [ABSTRACT FROM AUTHOR]

High Impedance Fault (HIF) detection in distribution networks is challenging for protection engineers, mainly because HIFs possess unique characteristics, including non-linearity, asymmetry, randomness, and relatively low fault current levels compared to the feeder load current. In this regard, the study proposes an approach to detect HIFs in a radial distribution feeder based on the spectrum analysis of current signals at the substation bus. The proposed method comprises two stages: signal decomposition and feature extraction. Fast Fourier Transform (FFT) is utilized for signal decomposition, followed by feature extraction. These features are subsequently used as input to an artificial neural network (ANN) to distinguish HIF from non-HIF events, such as linear and non-linear load switching, capacitor bank switching, and transformer energization. The proposed method's efficacy is rigorously evaluated under various dynamic conditions, demonstrating that the method can detect and differentiate HIFs from non-fault events with a high detection rate and high accuracy of 99.3%, irrespective of the HIF location and fault resistance. [ABSTRACT FROM AUTHOR]

Recently, the rapid progress of deep learning techniques has brought unprecedented transformations and innovations across various fields. While neural network-based approaches can effectively encode data and detect underlying patterns of features, the diverse formats and compositions of data in different fields pose challenges in effectively utilizing these data, especially for certain research fields in the early stages of integrating deep learning. Therefore, it is crucial to find more efficient ways to utilize existing datasets. Here, we demonstrate that the predictive accuracy of the network can be improved dramatically by simply adding supplementary multi-frequency inputs to the existing dataset in the target spectrum predicting process. This design methodology paves the way for interdisciplinary research and applications at the interface of deep learning and other fields, such as photonics, composite material design, and biological medicine. [ABSTRACT FROM AUTHOR]

We extend the law and economics analysis of spectrum management by considering the economic case for Indigenous and tribal spectrum sovereignty. We use case studies from the United States, Guatemala, Canada, and New Zealand to show that these movements seek a polycentric system of spectrum management that contrasts with the prevailing monocentric systems of spectrum management in which national governments have the primary authority over spectrum governance. Theories of polycentricity and federalism offer insight into the efficiency of Indigenous and tribal spectrum sovereignty as well as polycentric spectrum sovereignty more generally. [ABSTRACT FROM AUTHOR]

The theoretical and experimental characteristics of all-solid-state self-mode-locked burst pulse lasers are investigated in this study. The time–frequency and spectrum analyses of the lasers incorporating Fabry–Pérot (F-P) structures are presented, along with the development of the corresponding theoretical model. Self-mode-locked burst pulse lasers are experimentally constructed to reduce intracavity losses using the front and rear end surfaces of the gain media to form F-P structures. When the laser cavity length is 600 mm and the gain media lengths are 5, 6, and 10 mm, each burst pulse produced contains 56, 47, and 28 subpulses, respectively, with the same burst pulse width of 2 ns. The burst pulse train with beam quality M2 = 1.37 and an average output power of 0.23 W is obtained when the gain medium length is 5 mm and the pump power is 4.5 W. The corresponding burst pulse repetition frequency is 0.25 GHz and the subpulse repetition frequency is 13.66 GHz. The time–frequency spectral analyses of the laser signals provide a good representation of laser spectral information that even the currently available highest-resolution spectrometers cannot resolve. [ABSTRACT FROM AUTHOR]

Copyright of Journal of University of Anbar for Pure Science is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background Diffuse correlation spectroscopy (DCS) is a non-invasive optical technique that enables continuous blood flow measurements in various organs, including the brain. DCS quantitatively measures blood flow from temporal fluctuations in the intensity of diffusely reflected light caused by the dynamic scattering of light from moving red blood cells within the tissue. Methods We performed bilateral cerebral blood flow (CBF) measurements using a custom DCS device in patients undergoing neuroendovascular interventions for acute ischemic stroke. Experimental, clinical, and imaging data were collected in a prospective manner. Results The device was successfully applied in nine subjects. There were no safety concerns or interference with the standard angiography suite or intensive care unit workflow. Six cases were selected for final analysis and interpretation. DCS measurements with photon count rates greater than 30 KHz had sufficient signalto- noise to resolve blood flow pulsatility. We found an association between angiographic changes in cerebral reperfusion (partial or complete reperfusion established in stroke thrombectomy cases; temporary flow arrest during carotid artery stenting) and those observed intraprocedurally with CBF measurements via DCS. Limitations of the current technology included sensitivity to the interrogated tissue volume under the probe and the effect of local changes in tissue optical properties on the accuracy of CBF estimates. Conclusion Our initial experience with DCS in neurointerventional procedures showed the feasibility of this non-invasive approach in providing continuous measurement of regional CBF brain tissue properties. [ABSTRACT FROM AUTHOR]

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In the existing building stock, typically characterised by a high degree of irregularity, the effects of earthquakes are strongly dependent on the epicentre–structure direction and the angle of incidence of the seismic motion. However, the scientific community has not yet reached a unanimous consensus on the evaluation of the effects of seismic incidence angles. Therefore, this paper conducts an extensive investigation of the international literature on current methods to consider seismic directionality, systematically reviewing more than 80 publications on this topic. Following a brief overview of the problem and an analysis of the initial developments of the multidirectionality concept of seismic input, a state-of-the-art review is presented based on the considered analysis methods, specifically response spectrum analysis, nonlinear static analysis, and nonlinear response history analysis. Moreover, the adoption of multidirectional seismic input in popular codes and standards is presented and discussed. This study provides the first comprehensive synthesis of research on the seismic incidence angles across diverse building typologies, offering crucial insights for future code revisions and highlighting significant gaps in current analytical methods and standards, thereby setting a new direction for subsequent empirical investigations. Specifically, the extensive state-of-the-art review revealed that, until now, the evaluation of the angle of incidence was primarily conducted on existing reinforced concrete buildings with a limited number of storeys, analysed with nonlinear response history analysis. This underscores the need for future research to extensively investigate the impact of the angle of incidence on other types of construction typologies. [ABSTRACT FROM AUTHOR]

Today, BaFBr crystals activated by europium ions are used as detectors that store absorbed energy in metastable centers. In these materials, the image created by X-ray irradiation remains stable in the dark for long periods at room temperature. As a result, memory image plates are created, and they are extended to other types of ionizing radiation as well. Despite significant progress towards X-ray storage and readout of information, the mechanisms of these processes have not been fully identified to date, which has hindered the efficiency of this class of phosphors. In this study, using photoluminescence (PL), optical absorption (OA), Raman spectroscopy (RS), and atomic force microscopy (AFM), the luminescence of oxygen vacancy defects to BaFBr crystals irradiated with 147 MeV 84Kr and 24.5 MeV 14N ions at 300 K to fluences (1010–1014) ion/cm2 was investigated. BaFBr crystals were grown by the Shteber method on a special device. Energy-dispersive X-ray spectroscopy (EDX) analysis revealed the presence of Ba, Br, F, and O. The effect of oxygen impurities present in the studied crystals was considered. The analysis of the complex PL band, depending on the fluence and type of ions, showed the formation of three types of oxygen vacancy defects. Macrodefects (tracks) and aggregates significantly influence the luminescence of oxygen vacancy defects. The creation of hillocks and tracks in BaFBr crystals irradiated with 147 MeV 84Kr ions is shown for the first time. Raman spectra analysis confirmed that BaFBr crystals were amorphized by 147 MeV 84Kr ions due to track overlap, in contrast to samples irradiated with 24.5 MeV 14N ions. Raman and absorption spectra demonstrated the formation of hole and electron aggregate centers upon swift heavy ions irradiation. [ABSTRACT FROM AUTHOR]

Background: The objective of this study is to understand the characteristics of the common spectrum of pathogen and the resistance of Mycoplasma in Sialidase-positive bacterial vaginosis. Methods: The vaginal secretion specimens collected from August 2018 to October 2018 for the analysis of bacterial vaginosis (BV) were subjected to various techniques. These included routine leukorrhea examination, bacterial vaginosis sialidase testing, routine culture for common pathogens, mass spectrometry identification, and Mycoplasma resistance testing. Results: A total of 238 patients with BV were identified. The cleanliness grading was mostly clean (+) and clean (2+), accounting for 38.24% and 30.67%, respectively. The bacterial vaginosis test for vaginal secretions showed leukocyte esterase positivity in 220 cases, resulting in a positivity rate of 92.44%. The spectrum of routine culture was analyzed and divided into four groups: A, B, C, and D. Group A consisted of Candidal vaginitis (13.45%); group B consisted of Gardnerella vaginalis vaginitis (32.77%); group C consisted of gram-negative bacillus vaginitis (46.22%); and group D consisted of Streptococcus agalactiae vaginitis (7.56%). The identification and antimicrobial susceptibility testing results for Mycoplasma showed a high detection rate of BV, with a positivity rate of 86.13%. There was a high sensitivity to tetracyclines for Ureaplasma urealyticum and Mycoplasma hominis, but a high resistance to macrolides and quinolones. Conclusions: Bacterial vaginosis existed in various complex forms, including Candida, Gardnerella vaginalis, Gram-negative bacillus, and Streptococcus agalactiae types. Moreover, there was an increasing trend of multidrug resistance in Mycoplasma hominis. Therefore, it is crucial to pay attention to this condition and make accurate judgments based on the etiological characteristics and common antimicrobial susceptibility tests. This will enable the implementation of effective therapeutic interventions. [ABSTRACT FROM AUTHOR]

To build a new type of power system, the proportion of renewable energy sources with wind and solar energy as the main body has increased into the power grid. Due to the strong randomness and volatility of renewable energy as a power source, thermal power units need to fluctuate frequently to respond to system power requirements. To ensure the smooth operation of the thermal power units, a variable period day scheduling strategy considering spectrum analysis is proposed. Firstly, different dispatching periods are divided according to the characteristics of system net load fluctuation, secondly, to minimize the total cost, the joint dispatching model of wind power, solar energy, thermal power, and energy storage is established to form a day-ahead dispatching plan with variable time period. Finally, an example shows that this strategy can increase the smooth operation of thermal power units and improve the utilization rate of pumped storage units. [ABSTRACT FROM AUTHOR]

In this article, we propose a double reconfigurable intelligent surface (RIS)‐aided ambient backscatter communication (AmBC) network combined with non‐orthogonal multiple access (NOMA) technology, which not only successfully assists the base station (BS) in connecting with the cell edge user, but also enhances backscatter communication rate, energy efficiency, and spectrum efficiency. In an effort to obtain the highest backscatter communication rate, we design a RIS and BS‐based resource allocation problem which is solved by determining the optimal phase shifts of RISs and the optimal power allocation for signals of NOMA users. We break it down into two smaller challenges in order to discover the best solution. For one thing, we iterate the optimal phase shifts between the two RIS combinations using an alternating optimization technique. For another, the bisection method is used to provide the NOMA user with the ideal power allocation. Finally, the results of the simulation substantiate the viability of the proposed scheme. [ABSTRACT FROM AUTHOR]

With the recent advances in serial crystallography methods at both synchrotron and X-ray free electron laser sources, more details of intermediate or transient states of the catalytic reactions are being revealed structurally. These structural studies of reaction dynamics drive the need for on-line in crystallo spectroscopy methods to complement the crystallography experiment. The recent applications of combined spectroscopy and crystallography methods enable on-line determination of in crystallo reaction kinetics and structures of catalytic intermediates, sample integrity, and radiation-induced sample modifications, if any, as well as heterogeneity of crystals from different preparations or sample batches. This review describes different modes of spectroscopy that are combined with the crystallography experiment at both synchrotron and X-ray free-electron laser facilities, and the complementary information that each method can provide to facilitate the structural study of enzyme catalysis and protein dynamics.

Multi-walled carbon nanotubes (MWCNTs) were purified and unpurified in this study to obtain hybrid materials with improved activity. The production stage comprised a chemical purification of the produced sample. Raman spectroscopy analyzed the structural composition of purified and unpurified samples. The disc diffusion assay, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and time-kill assessment analyzed antimicrobial activity. MWCNT performed well against the tested bacteria (Klebsiella pneumoniae, Pseudomonas aeruginosa, Enterobacter aerogenes, Staphylococcus aureus, and Streptococcus sp. Staphylococcus epidermidis). The disc diffusion assay revealed inhibition zone differences caused by purified and unpurified MWCNTs. MIC and MBC values of purified and unpurified MWCNTs were similar. The purified and unpurified nanotubes of Staphylococcus epidermidis (ATCC 35985) exhibited inhibition zone diameters of approximately 8 mm and 9 mm, respectively. The microdilution method revealed a MIC of 1.23 mg/ml for the purified nanotube and 0.156 mg/ml for the unpurified nanotube against the same microorganism. The killing curve analysis demonstrated that unpurified carbon nanotubes were more effective against all tested microorganisms. MWCNTs represent a promising method for microbiology, but studies on the toxicity of these materials remain scarce.

The present study aimed to examine the impact of the level of physical activity on prefrontal cortex activation in older adults during single- and dual-task walking. Thirty physically inactive and 36 active older adults (60–85 years old) performed six 2-min tasks on a treadmill: two static cognitive tasks, two single-task walking tests, and two dual-task walking tests. Hemodynamics at the level of the prefrontal cortex were measured continuously using functional near-infrared spectroscopy to evaluate cortical activation. The perceived difficulty of the task, cognitive performance, and gait parameters were also measured. During the walking tasks, the level of prefrontal cortex activation, the perceived difficulty of the task, cognitive performance, and motor parameters were not significantly different between active and inactive older adults. This unchanged activation with physical activity was likely the consequence of a similar motor and cognitive load and cardiorespiratory fitness in both active and inactive older adults. [ABSTRACT FROM AUTHOR]

Rapid and cost-effective detection of antibiotics in wastewater and through wastewater treatment processes is an important first step in developing effective strategies for their removal. Surface-enhanced Raman scattering (SERS) has the potential for label-free, real-time sensing of antibiotic contamination in the environment. This study reports the testing of two gold nanostructures as SERS substrates for the label-free detection of quinoline, a small-molecular-weight antibiotic that is commonly found in wastewater. The results showed that the self-assembled SERS substrate was able to quantify quinoline spiked in wastewater with a lower limit of detection (LoD) of 5.01 ppb. The SERStrate (commercially available SERS substrate with gold nanopillars) had a similar sensitivity for quinoline quantification in pure water (LoD of 1.15 ppb) but did not perform well for quinoline quantification in wastewater (LoD of 97.5 ppm) due to interferences from non-target molecules in the wastewater. Models constructed based on machine learning algorithms could improve the separation and identification of quinoline Raman spectra from those of interference molecules to some degree, but the selectivity of SERS intensification was more critical to achieve the identification and quantification of the target analyte. The results of this study are a proof-of-concept for SERS applications in label-free sensing of environmental contaminants. Further research is warranted to transform the concept into a practical technology for environmental monitoring.

Alkyne-based Raman tags have proven their utility for biological imaging. Although the alkynyl stretching mode is a relatively strong Raman scatterer, the detection sensitivity of alkyne-tagged compounds is ultimately limited by the magnitude of the probe's Raman response. In order to improve the performance of alkyne-based Raman probes, we have designed several tags that benefit from π-π conjugation as well as from additional n-π conjugation with a sulfur linker. We show that the sulfur linker provides additional enhancement and line width narrowing, offering a simple yet effective strategy for improving alkyne-based Raman tags. We validate the utility of various sulfur-linked alkyne tags for cellular imaging through stimulated Raman scattering microscopy.