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Background: Diffusion kurtosis imaging is an advanced magnetic resonance imaging technique that reveals additional information on the microstructure and micro-dynamics of different brain masses without the need for contrast agents. The aim of this study was to provide a comprehensive analysis of the role of MRI diffusion kurtosis and to compare it with magnetic resonance spectroscopy (MRS) and dynamic susceptibility contrast perfusion (DSC) in characterizing different brain masses, including gliomas, recurrent tumors, radiation necrosis, abscesses, and infarctions. Sixty-six patients with intracranial brain masses were enrolled in this prospective study. All patients were examined by conventional MRI sequences, DSC perfusion, MRS, and diffusion kurtosis imaging, with implemented b values which were 200, 500, 1000, 1500 and 2000s/mm2. Results: Mean kurtosis (MK) was higher (P < 0.001) in recurrent brain tumors than in radiation-induced necrosis; the optimal MK cutoff value for differentiation between them was 642 with 91.3% sensitivity and 85.7% specificity. Mean kurtosis was also higher (P < 0.001) in high-grade gliomas than in low-grade gliomas; the optimal MK cutoff value for differentiation between them was 639 with 91.6% sensitivity and 85.71% specificity. There was a good level of agreement between ADC and MD within the studied cases, with a correlation coefficient r = 0.815. MK had more sensitivity and specificity in differentiation between high- and low-grade gliomas, as well as RIN and tumoral recurrence, than MRS and DSC. Conclusions: Diffusion kurtosis imaging stands as an integral, noninvasive, and noncontrast tool for the characterization of various brain masses. It augments the capabilities of traditional and advanced MRI techniques, providing a deeper understanding of the microstructural changes in brain tissues. [ABSTRACT FROM AUTHOR]

Software-Defined Radios are radio communications devices that have been growing and developing on a larger scale in recent years. Communications are intrinsically embedded in our day by day, thus presenting a higher motivation to use software-defined radios due to its attractive cost. However they present technical limitations. This paper addresses this problem, which is the non-linearity behaviour of gain and frequency in the LimeSDR-USB. That is, this equipment is used to produce a FM signal with an associated frequency and gain before being parameterised according to the internal parameters of each software-defined radio. Each software-defined radio presents a value of frequency and gain of its own, which correlates to the generated signals at the output level. To avoid this, machine learning networks were used, in which networks were trained to adapt to the non-linearity of these devices and correct it without the user noticing. This way, the user sets a desired frequency and gain in a signal, at the output of the software-defined radios, and a neural network calculates which values the software-defined radios should be parameterised, thus mitigating the non-linearity behaviour. This paper presents the evaluation of a laboratory prototype based on low-cost commercial software-defined radios equipment, to replace an expensive metrologically calibrated equipment used for radio frequency tests on a new concept of industrial test station, with description of the integration of Digital Twins, with their physical and virtual parts. [ABSTRACT FROM AUTHOR]

In the automotive industry, products must be tested and verified before being launched; currently, products such as automotive radio are usually tested with expensive metrology equipment, such as the Rohde & Schwarz SFE100, which produces radio frequency signals. This study assessed the feasibility of replacing the SFE100 with two inexpensive devices, Adalm-Pluto and LimeSDR usb, which are software-defined radios. For this evaluation, a study was carried out to determine specific metrological characteristics and then to compare with those of metrological equipment. Based on the results and tests of the study, we conclude that SDRs can generate test signals (FM, DAB, DVB, ISDB and SXM) with uncertainties of 0.5dBm and a spectral density ratio comparable to SFE100, thereby enabling their replacement. Furthermore, the evaluation datasets of all equipment have been publicly available [1] , enabling the scientific community to extract the metrological uncertainties for all signal carriers generated by the device. The result of this study proposes a methodology for testing auto radios that is innovative and can be applied to a production line based on the principles of Industry 4.0. [ABSTRACT FROM AUTHOR]

Temporal flow characteristics of a 3D centrifugal impeller suction system were numerically studied in vacuum conditions. The blockage of the high-speed rotating impeller appeared, which greatly dropped the suction of the layer suction device. The temporal flow characteristics of the 3D centrifugal impeller suction system were worthy of attention in vacuum conditions. Separation vortices were generated near the blade suction surface. The blocking mechanism of the passage was further analyzed at different extremely low flow rates through the time-space evolution of the streamline. The Q-criteria was introduced to analyze the vortex evolution within the fluid domain of the impeller. Vortex evolution law was captured--the vortices always generated near the suction surface of the blade and moved to the pressure surface of the adjacent blade in the same passage and disappeared. The uniform distribution of three stall cells was captured through the diagram of turbulent kinetic energy. The flow rate increased, and the vortex evolution period gradually decreased. The comparison of pressure fluctuations in different conditions further demonstrated the flow mechanism at the vacuum flow rate was different from that at low flow rates. The sharp increase of pressure fluctuations near the blade pressure surface was consistent with the phenomenon near the suction surface. The pressure fluctuation at extremely low flow was mainly composed of scattered fluctuations caused by fluid separation. The steady and unsteady characteristics described the internal flow characteristics of this suction system at vacuum-flow rates. Theresults provide a profound design for vacuum cleaners. [ABSTRACT FROM AUTHOR]

The types of injuries and types of striking elements were analyzed, the conditions of patients requiring urgent surgical intervention were assessed. The possibilities of existing means of diagnosing fragments in the patient’s body were analyzed, and it was concluded that for non-X-ray contrast fragments, the proposed method of mechanical contact with a special flexible and elastic probe is appropriate and effective. A special tool for examining wound canals has been developed, consisting of a flexible probe for individual use and a handle-holder with a microphone capsule, the membrane of which is directly connected to the probe and reacts to mechanical contact with an obstacle, and the capsule itself is directly connected to the oscilloscope through a signal amplifier. which has spectral signal processing circuits. The problem of the interaction of the elastic contact of a non-rigid element with a fragment located in a viscous medium is set, provided that the properties of the medium are not constant. Typical solutions of this problem for various types of fragments and parameters of the contacting element itself are presented. A picture of the noise emission accompanying the contact is shown. The functional dependence of noise emission parameters on the shape and type of the foreign object in the wound canal was revealed. The expediency of using the frequency-amplitude characteristic of noise radiation as a controlled parameter has been proven. A conclusion was made about the functional conditioning of the width of the signal spectrum and basic frequencies at the time of mechanical contact with a foreign object in the wound, depending on its shape and type; it was established that the use of an oscilloscope with a spectral analysis channel allows for the fairly accurate identification of a non-radiocontrast foreign object in a wound. [ABSTRACT FROM AUTHOR]

Low-frequency buffeting is a common problem in automobile wind tunnels, it induces pulsations of pressure and velocity in the test section. A 1:15 3/4 openjet return-type scaled wind tunnel was used for this research, and numerical simulations and tests were implemented to study the flow characteristics of the jet shear layer in a model wind tunnel. The results show that guide devices on the inner wall of the nozzle can effectively reduce the low-frequency buffeting, but the presence of the devices deteriorated the axial static pressure gradient of the flow in the test section. The shape of the guide devices was optimized through the Explorative Gradient Method, and numerical simulations were carried out. An optimal shape can effectively reduce the low-frequency buffeting and ensure flow field uniformity in the test section. Finally, the reliability of the numerical simulation and the practicability of the optimal case were verified through a hot wire test and a microphone test. [ABSTRACT FROM AUTHOR]

This paper deals with the seismic assessment of an existing Maillart-arch-type bridge. The evaluations concern a still-in-use deck-stiffened concrete arch bridge, the Viadotto Olivieri (Salerno, South Italy): it's an r.c. deck-arch bridge having a permanent-to-live loads ratio of 6:1. The seismic characterization has been supported by various FEM models. Multiple accurate analyses have been necessary to exploit effectively the potentials of this structural scheme before evaluating any possible retrofit strategies. With this aim, different schemes were checked, changing deck configurations and restraints at the base. The bridge has been modeled in a realistic way, using shells and beams. A preliminary linear analysis has been performed that consisted of applying a total horizontal force equal to 10% of the bridge's permanent loads in both plan directions. This displayed the most vulnerable elements, which were later also confirmed by modal outputs. The response spectrum analysis, assuming the seismic parameters of the site, showed that the highest effects occur for translational local modes in which only a few macro-elements are involved (monolithic behavior). The results also demonstrate the good performance of the Maillart-arch scheme in counteracting seismic loads. [ABSTRACT FROM AUTHOR]

Background One of the most common causes of exercise-induced pain in the lower leg is chronic exertional compartment syndrome (CECS). Research is limited on muscle strength, oxygen saturation and physical activity in patients with CECS. Purpose To compare muscle strength, oxygen saturation, and daily physical activity between patients with CECS and matched asymptomatic controls. A secondary purpose was to investigate the association between oxygen saturation and lower leg pain in patients with CECS. Study Design Case-control study. Method Maximal isometric muscle strength of the ankle plantar and dorsiflexors was tested in patients with CECS and sex- and age-matched controls using an isokinetic dynamometer and oxygen saturation (StO2) during running was tested by near infrared spectroscopy. Perceived pain and exertion were measured during the test using the Numeric Rating Scale and Borg Rating of Perceived Exertion scale and the exercise-induced leg pain questionnaire. Physical activity was assessed by accelerometry. Results Twenty-four patients with CECS and 24 controls were included. There were no differences in maximal isometric plantar or dorsiflexion muscle strength between patients and controls. Baseline StO2 was 4.5pp (95% CI: 0.7;8.3) lower for patients with CECS than for controls, whereas no difference existed when they experienced pain or reached exhaustion. No differences were found in daily physical activities, except that on average, patients with CECS spent less time cycling daily. During the StO2 measurement, patients experienced pain or reached exhaustion while running significantly earlier than the controls (p<0.001). StO2 was not associated with leg pain. Conclusion Patients with CECS have similar leg muscle strength, oxygen saturation and physical activity levels as asymptomatic controls. However, patients with CECS experienced significantly higher levels of lower leg pain than the controls during running, daily activities and at rest. Oxygen saturation and lower leg pain were not associated. [ABSTRACT FROM AUTHOR]

Landfill leachate concentrates is the waste solution trapped by nanofiltration/reverse osmosis (NF/RO) membrane in the biochemical effluent of landfill leachate. It has high content of salt and dissolved organic matter (DOM), especially refractory organic matter. Electrochemical oxidation of landfill leachate concentrates on Ti/RuO2-Ir/O2 anode, the electrolysis time and current density and plate distances was studied on the effects of the oxidation results. The results showed that, under the optimal conditions with initial pH value 7.8, current density 8 A/dm2, plate distances 1 cm, and electrolysis time 4 h, the chroma, COD, ammonia nitrogen and Cl- removal rates were 100%, 100%, 98% and 52%respectively. UV-vis spectrum analysis showed that the aromatization degree and relative molecular mass and polymerization degree decreased of DOM in the landfill leachate concentrates after electrolysis treatment. 3D-excitation emission matrix fluorescence spectra (3D-EEMFS) showed that humic acid was oxidized to humic acid with simpler structure and smaller relative molecular mass and soluble microbial degradation by-products in the landfill leachate concentrates after electrolysis treatment. FTIR analysis showed that the absorption intensity of organic compounds in the landfill leachate concentrates decreased and most organic compounds were oxidized and degraded after electrolysis treatment. [ABSTRACT FROM AUTHOR]

Optimal exposure to fluoride and calcium from tap water is beneficial for dental caries prevention. Water fountains may be an important source of drinking water in work and educational settings. The aims of this study were to quantify the fluoride and calcium concentrations of drinking water samples collected from public water fountains on the Indiana University-Purdue University Indianapolis campus; compare the fluoride and calcium concentrations in water collected at 2 different times; and determine whether the presence or absence of a visible external filter affects fluoride and calcium concentrations. Ninety samples were collected from 45 water fountains accessible to the public, and 90 duplicate samples were collected 1 month later. A fluoride ion-selective electrode was used in conjunction with an ion-specific meter to determine fluoride concentration, while atomic absorption spectrometry iii an air-acetylene flame was implemented to quantify the calcium concentration. The fluoride and calcium concentration of drinking water samples displayed ranges of 0.62 mg/L to 0.97 mg/L and 56.61 mg/L to 89.11 mg/L, respectively. The concentrations of fluoride and calcium in drinking water were slightly lower at the second collection period (P < 0.001; Wilcoxon signed rank test). No statistically significant differences were observed in the fluoride or calcium concentration of drinking water collected from water fountains with an external filter cartridge in comparison with fountains that did not have a filter. Fluoride concentrations were within the optimal range recommended by the US Public Health Service for fluoridated drinking water, and calcium concentrations were consistent with those reported in previous surveillance studies. [ABSTRACT FROM AUTHOR]

• We proposed a novel method for noise reduction of multichannel heart sound signals, which was based on FastICA algorithm and CNN model. • The method performs classification and consistency analysis of the independent components to extract reliable independent components of heart sounds. • The method improves the SNRs of each channel signal up to 20 dB, which is superior to the Wiener filtering and singular spectrum analysis (SSA). Various noises could contaminate heart sounds and yield inaccurate diagnosis. This paper proposed a framework of heart sound noise reduction using multi-channel structure. Multi-channel heart sound (MCHS) signals were preprocessed, and then decomposed into independent components (ICs) using FastICA algorithm. The ICs were evaluated for consistency using correlation analysis, and reliable ICs were identified. The reliable ICs were classified based on a convolutional neural network (CNN) into two groups: one is of ICs for heart sounds and the other is of ICs for noise, respectively. Consequently, the MCHS signals were reconstructed from the ICs group of heart sounds. To validate the proposed framework, the MCHS signals of 15 subjects were acquired and mixed with breath sounds under different signal-to-noise ratios (SNRs). the simulation results showed that the framework had effective noise reduction performances in suppressing the breath sounds. The SNR of the denoised MCHS could be improved to 20 dB. the proposed framework was better than traditional methods, such as Wiener filter and singular spectrum analysis (SSA). The practical applications proved that the framework is possible to reconstruct the heart sound signals in low signal quality situation. [ABSTRACT FROM AUTHOR]

Natural gas (NG) has been proposed as a bridging fuel between fossil and renewable energy sources, playing a significant role in the decarbonization of the energy sector. Its commercial value and the integrity of the NG infrastructure depend on the NG physical properties, which are strongly related to its composition. Thus, the development of low-cost and reliable analytical methods for composition analysis of NG can enable a more efficient operation. Recently, we showed that high-pressure (HP) benchtop 1H NMR spectroscopy combined with indirect hard modelling (IHM) is an efficient and low-cost method for composition quantification of NG. The current work extends this methodology by introducing and testing novel experimental strategies for increasing the reliability and accuracy of the method. This new approach includes the use of a recently published high-pressure tube design and single-scan acquisition combined with novel quality control parameters to obtain highly reproducible peak shape 1H NMR spectra over long periods. The proposed methodology tested on binary, ternary, and more complex mixtures at 200 bar and 160 bar gives compositions in excellent agreement with the vendor certificates. [Display omitted] • Novel experimental approach to obtain high-pressure multi-scan 1H NMR spectra. • Novel quality control parameters to select reproducible high-quality 1H NMR spectra. • New method to acquire the NMR spectra of higher-order hydrocarbons. • Indirect hard model developed at 200 bar is transferable to 160 bar. • NMR composition and physical properties in agreement with the vendor certificates. [ABSTRACT FROM AUTHOR]

Lithium sulfur (Li–S) batteries have received significant attention as one of the energy storage systems with excellent prospects for emerging applications due to their high energy density and low-cost. However, there are fundamental challenges impeding the commercialization of Li–S batteries. Notorious among those challenges is the “polysulfide shuttle” consisting of the dissolution into the electrolyte solvent and subsequent crossover to the anode of long-chain lithium polysulfides. Sparingly solvating electrolytes have been exploited as an approach to reduce the dissolution of polysulfides and thereby the shuttle effect. Using an optical in operando lithium-sulfur cell and ex situ UV–vis spectroscopy, we elucidate the speciation of polysulfides in fully and sparingly solvating electrolytes for Li–S batteries. Extensive literature meta-analysis reveals that the most unambiguous effect of sparingly solvating solvent is in improving the coulombic efficiency of sulfur-cells. Experimental optical imaging and UV–vis characterization elucidate a shift towards shorter-chain polysulfides in electrolytes with increasing lithium-salt concentration (more sparingly solvating). The shift to shorter-chain polysulfides corresponds to a reduction of polysulfide species participating in shuttling which corroborate the increased coulombic efficiency in sparingly-solvating electrolytes. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Dalian University of Technology / Dalian Ligong Daxue Xuebao is the property of Journal of Dalian University of Technology 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.)

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology 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.)

Electrochemical polishing (ECP) offers incomparable advantages and great potential in metal polishing by surface errors correction. This paper systematically investigates the ultimate roughness and surface errors correction ability of ECP over different spatial frequency ranges. This paper further explores the law of ECP influencing errors at different frequency ranges, proposes and clarifies the concept of critical spatial frequency, and studies the law of polishing parameters affecting critical spatial frequency by using spatial frequency spectrum analysis. The surface roughness evolution and ultimate roughness of ECP were investigated using the surface error filtering method based on the critical spatial frequency. The ultimate roughness of ECP was determined by two different strategies, (i) stepwise polishing and (ii) one-step polishing. In addition, the stepwise polishing was also investigated for any possible inconsistency with one-step polishing on the final surface roughness. As ECP progressed, the optimization speed of surface roughness gradually decreased, and the surface roughness eventually reached a stable limiting value. Further analysis revealed that crystal corrosion is mainly responsible for inhibiting surface roughness optimization. [ABSTRACT FROM AUTHOR]

Tropospheric ozone (O 3) causes widespread damage to vegetation; however, monitoring of O 3 induced damage is often reliant on manual leaf inspection. Reflectance spectroscopy of vegetation can identify and detect unique spectral signatures of different abiotic and biotic stressors. In this study, we tested the use of hyperspectral leaf reflectance to detect O 3 stress in alder, beech, birch, crab apple, and oak saplings exposed to five long-term O 3 regimes (ranging from daily target maxima of 30 ppb O 3 to 110 ppb). Hyperspectral reflectance varied significantly between O 3 treatments, both in whole spectra analysis and when simplified to representative components. O 3 damage had a multivariate impact on leaf reflectance, underpinned by changes in pigment balance, water content and structural composition. Vegetation indices derived from reflectance which characterised the visible green peak were able to differentiate between O 3 treatments. Iterative normalised difference spectral indices across the hyperspectral wavelength range were correlated to visual damage scores to identify significant wavelengths for O 3 damage detection. We propose a new Ozone Damage Index (OzDI), which characterises the reflectance peak in the shortwave infrared region and outperformed existing vegetation indices in terms of correlation to O 3 treatment. These results demonstrate the potential application of hyperspectral reflectance as a high throughput method of O 3 damage detection in a range of common broadleaf. species. [Display omitted] • Tropospheric ozone damage changes leaf reflectance of broadleaf saplings. • The hyperspectral reflectance signal of ozone damage is multivariate. • This signal has the potential be scaled up for monitoring ozone damage to forests. [ABSTRACT FROM AUTHOR]

Background: The primo vascular system can be viewed as a circulatory system that plays a therapeutic function in regenerating the body tissue. The anti-CD3 monoclonal antibody was used as an immunotherapeutic agent to treat the novel coronavirus infection (COVID-19). Objectives: In this study, we observed the effect of injecting lymph nodes with Foralumab, an anti-human CD3 epsilon therapeutic monoclonal antibody, on primo vessels. Methods: The structure and atomic stoichiometry of the antibody were determined by transmission electron microscopy and energy dispersive spectroscopy. Alcian blue dying solution was injected into the lymph nodes of the abdominal vena cava of rabbits, and the solution further flowed into the lymph vessels. Results: A primo vessel with primo nodes stained with Alcian blue was clearly visible in the lymph vessel. By injecting Foralumab into lymph nodes of rabbits with lipopolysaccharide-induced inflammation, the floating primo vessel in the lymph vessel appeared thicker and was distinctly visible. Conclusion: The observation of the primo vessel post-treated with Foralumab in the inflamed lymphatic system suggests the possibility of a functional role of the primo vascular circulatory system in pathophysiological conditions. [ABSTRACT FROM AUTHOR]

The purpose of this study was to identify sources and strategies for the mitigation of bias in studies of spinal manipulation and heart rate variability. A small-scale study compared the effects of a single session of sham and authentic cervical manipulation on heart rate variability as measured by power spectrum analysis. The participants were a sample of 31 healthy young students from the Canadian Memorial Chiropractic College, randomized into 2 study arms. The effectiveness of blinding was evaluated, and 2 alternative methods of data analysis were explored to mitigate risk of bias. Following execution of the study, the stages of implementation and data processing were scored against version 2 of the Cochrane risk-of-bias tool for randomized trials for risk of bias. The risk of bias arising from (1) the randomization process, (2) missing outcome data, and (3) selection of reported results was judged to be low. Risk of bias in (1) deviations from intended interventions (particularly due to the failure of masking) and (2) the measurement of the outcome, for example, through cleaning of the data, were judged to be high. The use of power spectrum analysis of heart rate variability based on 5-minute recordings of echocardiogram pre-and post-intervention contained multiple sources of bias that were challenging to mitigate. Based upon these findings, power spectrum analysis of heart rate variability using these parameters may be ill-suited to the study of physiological effects of spinal manipulative therapy. [ABSTRACT FROM AUTHOR]

Copyright of Biomédica: Revista del Instituto Nacional de Salud is the property of Instituto Nacional de Salud of Colombia 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.)

Development in the design of earthquake resistant buildings has been growing since about 100 years ago. In the design of earthquake resistant buildings, the main aspects to consider are life safety and damage reduction on architectural element caused by the earthquake. However, with the development of age, modern buildings contain sensitive and expensive equipment that become vital for business, commercial, education and healthcare. Hence, the equipment inside the building needs to be protected when the earthquake occurs. The basic principle of base isolation system is to provide flexibility in the building and at the same time provide damping to prevent amplification caused by the earthquake. By placing structure on the base isolation system, it will prevent horizontal movement of the ground transferred to the structure and produce a significant reduction in the acceleration of the earthquake. In the present study analysis of G+3 building analysis is carried out by using base isolation system rubber base system. The results like storey drift, storey shear, storey bending, time period, model frequency is analyzed by using Response spectrum analysis. [ABSTRACT FROM AUTHOR]

Endurance Time (ET) method is an efficient time history-based analysis procedure that applies special acceleration functions for estimating the seismic performance of structures at different excitation levels in every single analysis. For some structures with complex models, such as dams, it is impractical to conduct multiple seismic analyses due to the high computational cost. In such cases, for obtaining accurate structural responses, it is recommended that researchers pay conscious attention to choose compatible Endurance Time Excitation Functions (ETEFs) regarding the basic properties of their structures, such as the soil type of the site, the selected design spectrum, and the type of the analysis. However, in this study, it is observed that using various ETEFs to analyze a concrete moment frame subjected to a single earthquake ground motion will cause us to obtain unreliable responses. In other words, different ETEF series have significantly different accuracies (26% error) in predicting the responses of the mentioned structure which is subjected to individual earthquake ground motions. This problem is mainly caused by the turbulent nature of a single ground motion spectrum, which is in contrast to the smooth shape of the ETEF spectrum. One solution to avoid this problem could be to produce a specific ETEF. [ABSTRACT FROM AUTHOR]

In this paper, the power spectral density(PSD) for Multilevel Minimum Shift Keyed signal with modulation index h = 1/2 (M-ary MSK) are derived using the mathematical method of the Markov Chain model. At first, according to an essential requirement of the phase continuity characteristics of MSK signals, a complete model of the whole process of signal generation is built. Then, the derivations for autocorrelation functions are carried out precisely. After that, we verified the correctness and accuracy of the theoretical derivation by comparing the derived results with numerical simulations using MATLAB. We also divided the spectrum into four components according to the derivation. By analyzing these figures in the graphic, each component determines the characteristics of the spectrum. It is vital for enhanced spectral characteristics. To more visually represent the energy concentration of the main flap and the roll-down speed of the side flap, the specific out-of-band power of M-ary MSK is given. OMLCD(Optimum Maximum Likelihood Coherent Detection) of M-ary MSK is adopted to compare the signal received with prepared in advance in a code element T to go for the best. And M-ary MSK BER(Bit Error Rate) is compared with the same ary PSK (Phase Shift Keying) with M=2,4,6,8. The results show the detection method could improve performance by increasing the length of L(memory inherent) in the phase continuity. [ABSTRACT FROM AUTHOR]

By the finite element method, the structural vibration response is calculated under the action of the axial exciting force and the moment with different distribution form, and then the transfer function of the mean square normal velocity is analyzed. The wavenumber spectrum analysis method is used to separate and quantify the shell vibration in the wavenumber domain, and then the relation between the structural vibration characteristics and the structural wavelength is summarized. It is concluded that the structural vibration and radiated noise can be reduced under the symmetric action of axial exciting force and the moment. Based on the above conclusion, a symmetrical thrust bearing supporting system is designed and the stiffness of the supporting structure in the axial direction is controlled by selecting suitable size of structural members, therefore, the structural vibration and radiated noise of the submarine is reduced significantly. [ABSTRACT FROM AUTHOR]

The article focuses on voice science can help move us closer to evidence-based practices in our teaching, but adopting new tools can be challenging. Topics include the introduce high-tech tools that can improve our teaching and technophobic readers are encouraged to keep reading, the technology can come with a steep or even intimidating learning curve, and the center on perceptual training to help students better understand is vibrato using a voice synthesizer.

Parkinson's disease (PD) is a neuro-degenerative disease due to loss of brain cells, which produces dopamine. It is most common after Alzheimer's disease specially seen in old age people. In the earlier stage of disease, it has been noticed that most of the people suffering from speech disorder. From last two decades many studies have been conducted for the analysis of vocal tremors in PD. This study explores the combined approach of Variational Mode Decomposition (VMD) and Hilbert spectrum analysis (HSA) to investigate the voice tremor of patients with PD. A new set of features Hilbert cepstral coefficients (HCCs) are proposed in this study. Proposed features are assessed using vowels and words of PC-GITA database. The effectiveness of HCC features is utilized to perform classification, and regression analysis for PD detection. The highest average classification accuracy up to 91% and 96% is obtained with vowel /a/ and word /apto/ respectively. Further the classification accuracy up to 82% is obtained with independent dataset, when tested with the optimized model developed using PC-GITA database. In dysarthria level prediction highest correlation up to 0.82 is obtained using vowel /a/ and 0.8 with word /petaka/. The outcomes of this study indicate that the proposed articulatory features are suitable and accurate for PD assessment. [ABSTRACT FROM AUTHOR]

Spectrum sensing is a critical component of cognitive radio systems, enabling the detection and utilization of underutilized frequency bands. Convolutional neural networks (CNNs) and recurrent neural networks (RNNs), in particular, have showed promise in recent years for enhancing the precision and effectiveness of spectrum sensing. This paper presents an overview of spectrum sensing using CNNs and RNNs and their performance in cognitive radio systems. Furthermore, the paper delves into the spectrum sensing performance of RNNs, particularly for processing time-series data. RNNs are capable of capturing temporal dependencies in sequential data, which is essential for spectrum sensing tasks where signals evolve over time. Further, the parakeets such as probability of detection (Pd), Probability of false alarm (PFA), Bite Error rate (BER) and Power spectral density (PSD) are analysed for spectrum sensing algorithms. RNNs and CNNs, two examples of deep learning methods (DLM), performed better than more traditional approaches. [ABSTRACT FROM AUTHOR]

Background: Sepsis in children still shows a high mortality rate. Nutritional factors are important in the treatment of sepsis. Zinc is one of the key elements that can limit mitochondrial dysfunction due to an imbalance between reactive oxygen species and antioxidants that occur in sepsis. We aim to determine the effect of Pediatric Logistic Organ Dysfunction 2 (PELOD-2) score and zinc serum level before and after zinc supplementation in septic children. Methods: This is an experimental study with one group pretest-posttest design in patients aged 1 month to 18 years with sepsis treated at the PICU H. Adam Malik General Hospital from March 2018-February 2019. Oral zinc supplementation was given for 5 days. The PELOD-2 score and zinc serum level measurement were performed by using inductively coupled plasma-spectrometry (ICP-MS) on the first and fifth days. Bivariate analysis was performed by paired T test. Results: A total of 17 patients were analyzed. The paired T test showed significant difference in serum zinc levels before and after supplementation (p<0.001) even though the zinc levels were both still below normal values (28.7±11.7 µg/dl and 40.5±18.3 µg/dl, respectively). PELOD-2 score still showed increasing values with significant differences (p<0.001) before and after zinc supplementation (7.76±2.4 and 11.7±3.3, respectively). Conclusion: This was the first report that evaluated effect of zinc supplementation on PELOD-2 score. Zinc supplementation did not decrease PELOD-2 score but could give significant improvement in zinc serum level. [ABSTRACT FROM AUTHOR]

The purpose of this study was to describe the synthesis, characterization, and functionalization of b-NaYF4:30%Yb/0.5%Tm upconverting nanocrystals for use as nanofillers in a dental adhesive and microscopically evaluate the interface between the particles and a commercial adhesive. The upconverting nanoparticles were synthesized and purified by thermal decomposition, and their chemical composition determined by energy dispersive X-Ray spectroscopy. The crystalline structure was characterized using X-Ray diffraction and morphology and size were observed with scanning and transmission electron microscopy. Upconverting emission was evaluated by spectrophotometry irradiating the particles with a 975 nm diode laser. Particles were functionalized with polyacrylic acid and the success was confirmed by measurement of Zeta Potential and transmission electron microscopy. The results of X-ray diffraction found a pure hexagonal phase crystalline pattern. Scanning electron microscopy showed uniform dispersion of hexagonal-shaped particles of approximately 150 nm. Upconversion emission was observed in 344 nm, 361 nm, 450 nm, 474nm, 646 nm, 803 nm. Functionalization success was confirmed by formation of a stable aqueous colloid with a Zeta potential of -29.5mV and the absence of voids in the particle-adhesive interface on the transmission electron microscopy images. The reported synthesis and functionalization process produced upconverting nanoparticles emitting photons within the blue spectral region (450 nm and 474 nm). [ABSTRACT FROM AUTHOR]

Copyright of Journal of Medical Imaging & Radiation Sciences is the property of Elsevier B.V. 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.)

Detailed near- and far-field acoustic measurements were conducted for two circular stepped nozzles with 30°deg and 60°deg design inclinations at over- and perfectly-expanded supersonic jet flow conditions and compared to those for a circular nonstepped nozzle. Far-field acoustic results show that stepped nozzles play an insignificant role in altering noise emissions at perfectly expanded condition. At an over-expanded condition, however, the longer stepped nozzle produces significant noise reductions at the sideline and upstream quadrants, while the shorter stepped nozzle does not. Noise spectra analysis and Schlieren visualizations show that noise reduction can be primarily attributed to mitigations in the broadband shock-associated noise (BSAN), due to the ability of the longer stepped nozzle in suppressing shock strengths at downstream region. Near-field acoustic measurements reveal that the source region, as well as the intensity of turbulent and shock noises, are highly sensitive to the stepped nozzle configuration. Furthermore, BSAN seems to be eliminated by the longer stepped nozzle in near-field region due to the shock structure modifications. [ABSTRACT FROM AUTHOR]

• Influence of torrefaction intensity on a hemicellulose-rich biomass characteristics and pyrolysis behaviors was investigated. • The reductive immobilization mechanism of chromate, as a chemical surrogate for pertechnetate, on the torrefaction biochar was discussed. • Torrefaction biochar is a potential immobilization material for repairing Tc(VII) contaminated water. In this study, the torrefaction biochar from bamboo (Acidosasa longiligula) shoot shell under different torrefaction intensities (TI) were prepared and characterized. Nonradioactive Cr(VI), a chemical surrogate for radioactive Tc(VII), was used to evaluate Tc(VII) reductive immobilization of torrefaction biochar. Batch adsorption experiments indicated that torrefaction biochar had strong adsorption ability to Cr(VI) with the best uptake capacity of 63.11 mg/g. The adsorption kinetic was well fitted by pseudo-second-order model and Park model. The adsorption equilibrium was considerably fitted by Freundlich and Temkin isotherm The adsorption-reduction mechanism during the whole Cr(VI) immobilization process was confirmed by the Raman spectrum analysis and the nice fitting of Park model. This study demonstrates that torrefaction biochar deserves to be a low-cost and effective immobilization material for Tc(VII). [ABSTRACT FROM AUTHOR]

Toothbrushes act as a reservoir for a variety of microorganisms, possibly leading to oral infection. Some manufacturers are marketing toothbrushes that incorporate materials such as charcoal in their bristles and claiming that they reduce bacterial contamination. The present study aimed to explore the antimicrobial nature of charcoal-infused and non-charcoal-infused bristles and to characterize both bristle types physically and morphologically to ascertain any differences that might influence their antimicrobial activity. The antimicrobial property was analyzed using separate standard microbial solutions of Streptococcus mutans and Candida albicans to contaminate 40 commercially available toothbrushes of each bristle type, charcoal-infused and non-charcoal-infused (80 toothbrushes total), and microbial colonies were established. Each toothbrush head was rinsed 4 times in sterile tap water to simulate the brushing cycle, and the microbial counts of the rinsing solutions were recorded after the second and fourth rinses. After the fourth rinse, the toothbrush heads were left to dry for 20 hours, and the final microbial retention counts were recorded. The physical and morphologic characteristics of both bristle types were analyzed using Laser Raman spectroscopy, energy-dispersive X-ray spectroscopy, and scanning electron microscopy. The microbiologic analysis showed a statistically significant decrease in colony counts from initial exposure to final retention of both microbes for both types of toothbrush (P < 0.05; Wilcoxon signed rank test). However, intergroup comparisons showed no significant differences between the brush types in final retention of either microbe. Raman spectroscopy showed similar carbon compositions for both types of bristle. No significant difference was found between the 2 types of toothbrushes regarding their characterization or antimicrobial activity. Therefore, before charcoal-infused toothbrushes are marketed as a means to reduce contamination, there is a need to identify an appropriate concentration, ascertain the mechanism of action, and Identify the pathogen-specific action of charcoal. [ABSTRACT FROM AUTHOR]

15-F2T-isoprostanes are byproducts of lipid peroxidation and were determined to be the best marker of oxidative injury in a rodent model of oxidative stress. A previous study compared methods for measurement of urinary F2-isoprostanes (gas chromatography and negative ion chemical ionization–mass spectrometry, GC-NICI-MS; and ELISA) and found poor agreement in dogs, horses, and cows. Surprisingly, fair agreement between these methods was identified in a small population of cats. We evaluated the agreement between GC-NICI-MS and ELISA of urinary F2-isoprostanes in the urine of 50 mature cats ranging from healthy to systemically ill. All urine samples had detectable levels of F2-isoprostanes by both methods. Significant proportional bias and poor agreement were identified between the 2 methods (ρ = 0.364, p = 0.009) for all cats, and in subgroup analysis based on health status. The concentration of urinary F2-isoprostanes was significantly lower in systemically ill cats compared to healthy cats when measured by ELISA (p = 0.002) but not by GC-NICI-MS (p = 0.068). Our results indicate that GC-NICI-MS and ELISA have poor agreement when measuring urinary F2-isoprostanes in cats. [ABSTRACT FROM AUTHOR]

The volute tongue, as the crucial component inducing rotor-stator interaction, is detrimental to unsteady pressure pulsations of centrifugal pumps. In the present paper, to investigate the effect of the volute tongue cut on pressure pulsations of a low specific speed centrifugal pump, three volute tongues are obtained through twice cuts, named cases 1, 2, 3. Twenty measuring points are evenly mounted on periphery of the volute casing to obtain unsteady pressure signals using high response transducers. Pressure amplitudes at the blade passing frequency fBPF and root mean square (rms) values in 0 Hz-500 Hz frequency band are applied to evaluate the cutting effect. Results show that pressure spectrum is significantly affected by the volute tongue cut, especially for the component at fBPF. For different measuring points, influences of the volute tongue cut on three cases are not identical. From rms values, it is evident that cutting the volute tongue will lead to pressure energy increasing for most of the concerned measuring points, especially for the points at the far away region from the volute tongue. Finally, from comparison with the original shape case 1, the averaged increment of the twenty points is more than 20%. So it is concluded that for this type centrifugal pump, cutting the volute tongue is not reasonable considering low pressure pulsation requirement. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the effects of radiofrequency electromagnetic field (RF EMF) on heart rate variability (HRV) in rabbits with intensity slightly exceeding the limits for occupations. Totally 21 New Zealand white rabbits divided into two groups were used in this double-blind study. The first group of animals without general anesthesia was subjected to HRV examination under exposure to a device generated RF EMF source (frequency 1788 MHz, intensity 160 V/m, lasting 150 min.). The second group (premedications + a chloralose mg/kg) underwent the same protocol under the exposure to the real RF EMF signal from the base stations of mobile providers (frequency range 1805 - 1870 MHz - corresponding to the downlink signal of Slovak mobile providers, 160 V/m, 150 min., respectively). Individual 5-min records were used to analyze the HRV parameters: heart rate and root Mean Square of the Successive Differences (rMSSD) for time domain analysis and spectral powers in the low (LF-VFS) and high frequency (HF-VFS) bands for frequency domain analysis. Our study revealed the increased in HRV parameters (HF-HRV, rMSSD) associated with lower heart rate indicating increased cardiac vagal control under the exposure to RF EMF in experimental methods. [ABSTRACT FROM AUTHOR]

Steady-state visual evoked potential (SSVEP) based brain–computer interfaces have been widely studied because these systems have potential to restore capabilities of communication and control of disable people. Identifying target frequency using SSVEP signals is still a great challenge due to the poor signal-to-noise ratio of these signals. Commonly, this task is carried out with detection algorithms such as bank of frequency-selective filters and canonical correlation analysis. This work proposes a novel method for the detection of SSVEP that combines the empirical mode decomposition (EMD) and a power spectral peak analysis (PSPA). The proposed EMD+PSPA method was evaluated with two EEG datasets, and was compared with the widely used FB and CCA. The first dataset is freely available and consists of three flickering light sources; the second dataset was constructed and consists of six flickering light sources. The results showed that proposed method was able to detect SSVEP with high accuracy (93.67 ± 9.97 and 78.19 ± 23.20 for the two datasets). Furthermore, the detection accuracy results achieved with the first dataset showed that EMD+PSPA provided the highest detection accuracy (DA) in the largest number of participants (three out of five), and that the average DA across all participant was 93.67 ± 9.97 which is 7% and 4% more than the average DA achieved with FB and CCA, respectively. [ABSTRACT FROM AUTHOR]

Critical illness can threaten the adequacy of O2 delivery or CO2 excretion. Monitoring seeks to identify the adequacy of oxygenation and ventilation and to detect deterioration early. Advances in oximetry, capnography, and transcutaneous CO2 monitoring offer new opportunities for more accurate estimation of gas exchange, noninvasive monitoring of parameters previously not amenable (eg, total hemoglobin measurement), detection of disease, and prediction of fluid responsiveness. [ABSTRACT FROM AUTHOR]

There are five stages in acid coagulation of milk and most studies miss out on a stage or two depending on the experiments performed. Dielectric studies of milk and various physico-chemical studies on the formation of yogurt are well studied and established. However, most of the papers deal with either a limited range of frequencies in the dielectric studies and hence are unable to reflect all the mechanisms of coagulation that occur, or are done as stand-alone experiments, with no correlations to other physico-chemical processes. In this paper, we discuss the broadband dielectric spectroscopy of lactic-acid coagulation of milk, identify the various stages, and compare it with pH, zeta potential, particle size and microscopy. We establish the superiority of dielectric spectroscopy in the identification of all stages of coagulation, the indifference of the process to fat content. Further a strong correlation between tan δ and pH is seen, that is an indicator of the five different stages of lactic-acid induced coagulation. Penetration depth is calculated as milk coagulates and it is seen to be decreasing with coagulation. Broadband dielectric spectroscopy is seen to reveal the onset of coagulation much earlier than other experimental techniques discussed here. [ABSTRACT FROM AUTHOR]

Developing effective and economical materials for emerging electrochemical remediation of persistent organic pollutants has attracted significant research interest. In this study, a heteromorphic self-standing nickel foam@Ni(OH)2/MnO2 (NF@Ni(OH)2/MnO2) electrode was synthesized by a simple solvothermal method and employed for the remediation of persistent organic pollutants. The prepared NF@Ni(OH)2/MnO2 electrode exhibited better performance for the electro-catalytic degradation of tetracycline (TC) than that of the NF and NF@Ni(OH)2. In optimized conditions, the NF@Ni(OH)2/MnO2 electrode exhibited the highest TC degradation efficiency (90%) and total organic carbon(TOC) removal (59.02%) among the prepared electrodes. In addition, a higher mineralization current efficiency (MCE) and lower energy consumption (EC) for the NF@Ni(OH)2/MnO2 electrode was achieved. The enhancement occurs primarily because the active MnO2 anchored to the porous and highly conductive Ni foam substrate surface boosts the electron transfer and the generation of hydroxyl radicals, as proved by a free radical trapping experiment and fluorescence spectrum analysis. This study suggests the possibility of a new paradigm in designing effective and practical electro-Fenton electrodes for environmental remediation [ABSTRACT FROM AUTHOR]

With the increased availability of real-time data streams in different domains comes the opportunity of using this data to provide valuable insights into the performance of the systems generating such data. In this paper, we are proposing an anomaly detection method to be applied on road traffic data in intelligent transportation systems. The proposed scheme is based on multi-channel singular spectrum analysis (MSSA), and aims to characterize the spatio-temporal properties of the transportation network. By simultaneously analyzing the spatial and temporal attributes of the network, the proposed anomaly detection scheme is able to detect contextual and collective anomalies that are otherwise undetectable using only spatial or temporal anomaly detection techniques. This is indicated through the results shown in the experiments and results section. [ABSTRACT FROM AUTHOR]

Although an inverse relationship between body mass index (BMI) and baroreflex sensitivity (BRS) was found, the effect of waist circumference (WC) on BRS is still inconclusive. The contradictory results of previous studies may be related to the heterogeneity and relatively small sample size of the subjects examined. The aim of this population-based study was to investigate whether the influence of increased WC is more detrimental to BRS than BMI. A total of 760 community dwellers were recruited and they were classified into Q1 (n = 189), Q2 (n = 183), Q3 (n = 192) and Q4 (n = 196) groups, based on WC quartiles. Spontaneous BRS was determined by spectral α coefficient method. Valsalva ratio was the longest RR interval after release of Valsalva maneuver divided by the shortest RR interval during maneuver. Cardiac autonomic function was calculated by power spectrum of heart rate in low and high frequency (LF, 0.04–0.15 Hz; HF, 0.15–0.40 Hz), and LF/HF ratio in supine position for five minutes. There were significant differences in spontaneous BRS and Valsalva ratio among different WC groups. In multivariate analysis, obesity was inversely associated with spontaneous BRS and Valsalva ratio. However, these inverse relationships became insignificant after further adjustment for WC quartiles. In contrast, Q4 vs. Q1, Q3 vs. Q1 and Q2 vs. Q1 of WC were inversely related to spontaneous BRS. Q4 vs. Q1 and Q3 vs. Q1 of WC were negatively associated with the Valsalva ratio. In conclusion, increased and even high-normal WC had a stronger adverse effect on BRS than BMI, independent of cardio-metabolic risk factors. [ABSTRACT FROM AUTHOR]

Copyright of Konuralp Medical Journal / Konuralp Tip Dergisi is the property of Duzce University Medical School 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.)