Search

In this research, we examine laser-induced periodic surface structures (LIPSS) [1] on conducting indium-tin-oxide thin films produced by 2-µm femtosecond pulses in ambient air. We present diverse surface morphologies around the focal spot and assign local threshold peak intensity values to the different structure formations.

International audience; Interaction of intense femtosecond laser pulses with transparent materials has been a topic of growing interest in the past decades [1] . Among others, two features are particularly attractive. First, unprecedented material processing quality can be achieved as very small amount of energy is sufficient to induce the desired modification. Second, owing to localization of the laser peak intensity and the threshold-dependent nonlinear interaction, three-dimensional processing of transparent materials becomes possible. Although a growing number of applications exist [2] , several limitations are present. As an example, there is an everlasting need to minimize the laser affected volume and thus avoid unwanted crack propagation or mechanical defect generation during in-bulk material processing.

We developed a new surface-enhanced Raman scattering (SERS)-based aptasensor platform capable of quantifying severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) lysates with a high sensitivity. In this study, a spike protein deoxyribonucleic acid (DNA) aptamer was used as a receptor, and a self-grown Au nanopopcorn surface was used as a SERS detection substrate for the sensible detection of SARS-CoV-2. A quantitative analysis of the SARS-CoV-2 lysate was performed by monitoring the change in the SERS peak intensity caused by the new binding between the aptamer DNA released from the Au nanopopcorn surface and the spike protein in the SARS-CoV-2 virion. This technique enables detecting SARS-CoV-2 with a limit of detection (LoD) of less than 10 PFU/mL within 15 min. The results of this study demonstrate the possibility of a clinical application that can dramatically improve the detection limit and accuracy of the currently commercialized SARS-CoV-2 immunodiagnostic kit.

Forecasts of tropical cyclones (TCs) of the western North Pacific basin during the period of July to August 2018, especially of Rumbia (2018), Ampil (2018) and Jongdari (2018) that made landfall over Shanghai, have opposed great challenges for numerical models and forecasters. The predictive skill of these TCs are analyzed based on ensemble forecasts of ECMWF and NCEP. Results of the overall performance show that ensemble forecasts of ECMWF generally have higher predictive skill of track and intensity forecasts than those of NCEP. Specifically, ensemble forecasts of ECMWF have higher predictive skill of intensity forecasts for Rumbia (2018) and Ampil (2018) than those of NCEP, and both have low predictive skill of intensity forecasts for Jongdari (2018) at peak intensity. To improve the predictive skill of ensemble forecasts for TCs, a method that estimates adaptive weights for members of an ensemble forecast is proposed. The adaptive weights are estimated based on the fit of ensemble priors and posteriors to observations. The performances of ensemble forecasts of ECMWF and NCEP using the adaptive weights are generally improved for track and intensity forecasts. The advantages of the adaptive weights are more prominent for ensemble forecasts of ECMWF than for those of NCEP.

Herein, we attempted to prepare MoS2/Fe@Fe3O4 nanocomposites capable of strongly absorbing broadband incident electromagnetic (EM) radiation and probed the effects of their composition on complex permittivity and permeability at 2–18 GHz. Calculations of normal-incidence reflection losses (RLs) based on EM parameters revealed that the Fe@Fe3O4 to MoS2 mass ratio strongly influenced the absorption peak intensity and bandwidth. Specifically, an RL peak of −31.8 dB@15.3 GHz and a bandwidth (RL

An ionospheric heating experiment was conducted using the dual-pump mode at the EISCAT/HEATING facility in Tromso, Norway. Some new features were found in the downshifted maximum (DM) component of the stimulated electromagnetic emission (SEE) spectra. During the experiment, the DM1 generated by pump 1 was enhanced under the action of pump 2 with the peak intensity being increased by ∼4.8–9.8 dB to achieve maximum value, when the frequency of pump 2 was 4.100 MHz. The gyro resonance at the upper hybrid altitude played an important role in this phenomenon. It was also observed that the development time of DM2 generated by pump 2 was greatly shorter than that of DM1 due to the precondition provided by the artificial field-aligned irregularities (AFAIs) stimulated by pump 1. Additionally, the frequency offset and peak intensity of the DM1 spectrum showed a significant negative correlation, where the correlation coefficient reached a value of −0.91.

Active capture and ultrasensitive SERS-based detection of hexachlorocyclohexane (HCH) has been a challenging task. A novel strategy based on 4-mercaptophenylboronic acid (4-MPBA) surface modification on Au nanosheets-built hollow sub-microcubes (ANHCs) was proposed to capture HCH pesticides effectively via Suzuki cross coupling reaction. The ANHCs structure composed of numerous intertwined nanosheets was firstly prepared by Au nanocrystals heteroepitaxial growth on AgCl cubes. Then, the 4-MPBA molecules were selected to modify on the surface of ANHCs for SERS-based detection of HCH. The SERS results proved that active capture and ultrasensitive detection of HCH could be implemented, and the limit of detection is 0.3 ppb. Besides, 4-MPBA modified substrate show high reproducibility and sensitivity than unmodified one. Moreover, the characteristic peak intensity ratio IHCH/I4-MPBA presents a good linear relationship with the logarithm of a certain concentrations, and achieve SERS-based quantitative detection of HCH. In addition, this strategy has been successfully used for the detection and differentiation of mixed HCH isomers in water samples. The surface modification strategy on high performance SERS substrate provides a good route for the highly ultrasensitive detection and active capture of HCH, and paves a way for the detection of organochlorine pesticide residues in water samples.

The present work examined factors affecting the intelligibility of high-intensity-level-based speech. Mandarin sentences were processed to contain only high-intensity segments confined by a 5-dB selected intensity range (SIR), with other segments replaced by noise. The processed stimuli were presented to normal-hearing listeners to recognize. The greatest intensity density occurred in the SIR with an upper boundary 3 dB below the peak intensity level, and this SIR yielded the highest intelligibility score in quiet. The SIR with the upper boundary at the peak intensity level yielded better intelligibility performance under noisy conditions, due largely to the relatively high effective signal-to-noise ratio.

Based on the nonlinear Schrodinger equation, we discuss the variation dynamics of the peak intensity of high-order rogue wave with shift parameters theoretically, and reveal a non-derivable transformation point in it. The critical behavior of rogue waves shows that the ultimate cause of the transformation point is the ephemeral four-peak state of them. As a practical example, we discuss the experimental feasibility for observing the transformation point in nonlinear fiber optics.

Effects of low-frequency electromagnetic fields (LF EMF) on the activation of different tissue recovery processes have not yet been fully understood. The detailed quantification of LF EMF effects on the angiogenesis were analysed in our experiments by using cultured human and mouse endothelial cells. Two types of fields were used in the tests as follows: the LF EMF with rectangular pulses, 340-microsecond mode at a frequency of 72 Hz and peak intensity 4 mT, and the LF EMF with sinusoidal alternating waveform 5 000 Hz, amplitude-modulated by means of a special interference spectrum mode set to a frequency linear sweep from 1 to 100 Hz for 6 s and from 100 Hz to 1 Hz return also for 6 s, swing period of 12 second. Basic parameters of cultured cells measured after the LF EMF stimulus were viability and proliferation acceleration. Both types of endothelial cells (mouse and human ones) displayed significant changes in the proliferation after the application of the LF EMF under conditions of a rectangular pulse mode. Based on the results, another test of the stimulation on a more complex endothelial-fibroblast coculture model will be the future step of the investigation.

1H and 2H NMR spectra of 4 natural and synthetic nicotine samples were collected in a non-quantitative way and site-specific 2H/1H peak intensity ratio (SPIR) was calculated for 12 distinct sites of nicotine. Experimental results illustrated that the SPIRs at sites of 6, 2′, and 5′β of natural nicotine were significantly different from those of the synthetic nicotine, and could be used for nicotine authentication as the measured SPIRs were indicative of the site-specific natural isotope fractionation. We demonstrated that this method could be applied to detect adulteration of natural nicotine with as low as 20% synthetic nicotine, without the need to measure the site-specific δD values, which usually required time-consuming quantitative 2H NMR and additional IRMS for the overall 2H/1H isotopic ratio determination. The distinguishable 2H/1H SPIRs of nicotine, which can be quickly measured by NMR in non-quantitative way, can serve as an attractive alternative tool for tobacco authentication.

The potential of high-performance thin-layer chromatographic (HPTLC) fingerprinting in identifying differences in sandalwood essential oils from 5 sandalwood species, namely, Santalum album, Santalum spicatum, Santalum austrocaledonicum, Santalum paniculatum, Santalum lanceolatum, and a natural substitute for sandalwood, Osyris lanceolata, was explored. Variation was observed in the profile of bands (RF values and color) and peak intensity profiles displayed by the essential oils across and within the essential oils studied with some bands being unique to the individual species. The potential of HPTLC fingerprinting as a quality control tool in authenticating sandalwood oils in the sandalwood industry was demonstrated in the present study.

We have established a data set of 58 major hybrid SEP events associated with meter-to-decahectometer wavelength (m-to-DH) type II bursts, solar flares, and radio-load CMEs during the period of 1997–2014. The main focus of our study is to address the following two questions: Does the interaction of CMEs play a role in the enhancement of SEP intensity? Is there any difference in the seed population, and parent eruptions in the SEP events with and without CME interactions? Hence, the sample of 58 events is classified into two sets: (i) 35 non-interacting-CME-associated SEP events; (ii) 23 interacting-CME-associated SEP events. All the characteristics of SEPs, their associated CMEs/flares and the relationships between them are statistically analyzed and compared. Some of the basic attributes and relative elemental abundances (Fe/O ratios) of the both the sets are also compared. The results indicate that the seed particles in non-interacting-CME-associated SEP events are mostly from solar wind/coronal materials. But in the case of interacting-CME-associated SEP events, it may be associated with both flare material from preceding flares and coronal materials from solar wind/preceding CMEs. The correlation studies reveal that there are clear correlations between logarithmic peak intensity of SEP events and properties of CMEs (space speed: cc = 0.56) and solar flares (peak intensity: cc = 0.40; integrated flux: cc = 0.52) for non-interacting-CME-associated SEP events. But these correlations are absent for the interacting-CME-associated events. In addition, the results suggest that interaction of primary CMEs with their preceding CMEs plays an important role in the enhancement of peak intensity of SEPs at least for a set of m-to-DH type II bursts associated SEP events.

Based on a SERS study, the plasmon-assisted coupling reaction of p-iodoaniline (PIAN) to p,p′-diiodoazobenzene was investigated. This model plasmon-assisted reaction exhibits an outstanding SERS performance with the limit of detection as low as 10–13 M. Under low concentrations, the control of the cis–trans isomerization of p,p′-diiodoazobenzene was achieved by characterizing the Raman peak intensity at 1432 cm–1 of the coupling reaction catalytic product. We present the regulation strategy for the isomerization of azobenzene derivatives enabled here, through the controlled adjustment of reactant concentration, and expand the application of SERS technique.

In this paper, we study the collision properties of rogue waves in optical fiber theoretically. Based on the triplet solution of the nonlinear Schrodinger equation with two parameters, the factors that affect the initial conditions of colliding rogue waves are discussed. Meanwhile, the variation dynamics of peak intensity in collision is studied with each parameter, and the approximate formula of this variation law is derived by drawing an analogy between the collision of rogue waves and that of classical particles, which is consistent with the numerical results. The variation with both two parameters is also discussed, which is found the abnormal behavior of peak intensity in this case. This effect can be potentially used to generate rogue waves with higher peak intensity in optical fiber, which is confirmed by our simulation results.

Respiratory syncytial virus (RSV) infections peak during the winter months in the United States, yet the timing, intensity, and onset of these outbreaks vary each year. An RSV vaccine is on the cusp of being released; precise models and accurate forecasts of RSV epidemics may prove vital for planning where and when the vaccine should be deployed. Accurate forecasts with sufficient spatial and temporal resolution could also be used to support the prevention or treatment of RSV infections. Previously, we developed and validated an RSV forecast system at the regional scale in the United States. This model-inference system had considerable forecast skill, relative to the historical expectance, for outbreak peak intensity, total outbreak size, and onset, but only marginal skill for predicting the timing of the outbreak peak. Here, we use a superensemble approach to combine three forecasting methods for RSV prediction in the US at three different spatial resolutions: national, regional, and state. At the regional and state levels, we find a substantial improvement of forecast skill, relative to historical expectance, for peak intensity, timing, and onset outbreak up to two months in advance of the predicted outbreak peak. Moreover, due to the greater variability of RSV outbreaks at finer spatial scales, we find that improvement of forecast skill at the state level exceeds that at the regional and national levels. Such finer scale superensemble forecasts may be more relevant for effecting local-scale interventions, particularly in communities with a high burden of RSV infection. Keywords: RSV, Superensemble, Forecast, Infectious disease, Bayesian modeling, Outbreaks, Epidemics, Computational biology

The aim of this work is to establish the correlation between differential scanning calorimetry and Raman spectroscopy in the determination of the mechanical properties of TiO2/epoxy resin nanocomposites. Commercial RTM6 epoxy resin with TiO2 nanoparticles of 21 nm in diameter is used. Magnetic stirring for 5, 30, and 60 min is employed for the preparation of this epoxy. The rate of the reticulation of epoxy is reinforced by different percentages of TiO2 nanoparticles and is strongly affected by the cure temperature. The results indicate that the 1255 cm–1 peak intensity, corresponding to the C–C stretch, decreases during the cure leading to the variation of the mechanical properties (hardness) of the nanocomposites.

Objective To assess quantitative perfusion of intra‐ and extraocular regions of interest (ROIs) in conscious, healthy dogs utilizing contrast‐enhanced ultrasonography (CEUS); to compare varying enhancement with the first and second bolus injection and in the right and left eye; and to determine the most appropriate examination time. Procedures Gray scale ultrasonography and contrast harmonic imaging using sulfur hexafluoride were performed randomly assigned in both eyes in 10 university‐owned beagles. Perfusion parameters including slope time, time to peak (TTP), peak intensity (PI), and area under the curve (AUC) were measured at individually drawn ROIs (retrobulbar cone = ROI 1, choroid‐retina complex = ROI 2, medial = ROI 3, and lateral anterior uvea = ROI 4). Results Time‐intensity curve parameters revealed no significant differences in eyes examined by the first or second bolus injection (P > 0.05) or in the right or left eye (P > 0.05). Pooled data from all eyes were analyzed. Peak intensity of ROI 2 was significantly higher compared to all other ROIs (P 0.05). Ratios relative to different ROI sizes showed fastest enhancement in the retrobulbar cone and most intense perfusion in the anterior uveal regions. The first minute after contrast injection provided the highest diagnostic value. Conclusion Quantitative perfusion in nondiseased canine eyes revealed consistent parameters. Application of standardized CEUS protocols may be a promising diagnostic tool to differentiate ocular lesions.

Here we solve the problem of estimating the Raman frequency shift and the changes to Raman peak intensity due to doping (or changing chemical composition) and temperature consistently. The formalism employed to derive the temperature and doping-dependent Raman intensity ratio [or the ionization energy theory (IET)-based Raman intensity ratio] formula is based on the IET and the energy-level spacing renormalization group method. Therefore, our formalism is entirely based on first principles that does not require any guessed wavefunction nor intrinsic adjustable parameter anywhere in our analysis. The IET-Raman theory is then applied to Si(111), CdS, CdSe, $$\text{Cd}_{1-x}\text{Ca}_x\text{TiO}_3$$ and 6H–SiC in order to expose the changes observed in the Raman spectra with respect to their peak intensity and frequency shift. We shall prove and highlight that the experimental Raman spectra obtained for the above-stated materials obey the physicochemical mechanism derived from the IET-Raman intensity formula unambiguously and without any exception. It is worth noting that the said formula can be implemented in all Raman spectroscopy machines as an additional feature to predict the Raman frequency shift and the Raman peak intensity with respect to temperature and changing chemical composition.

Blue-shifting H-bonded complexes between CHCl3 and CH/D3CN have been identified by Fourier transform infrared spectroscopy in the gas phase at room temperature. The change in FTIR peak intensity of the mixture of the two components as a function of temperature and composition provides the basis for identification of the H-bonded band in the infrared spectrum. On complex formation with CH3CN and CD3CN, the C−H stretching frequency of CHCl3 shifts to the blue by +8.7 and +8.6 cm−1, respectively. The molecular electrostatic potential calculation at the MP2/6-311++G** level has been used to arrive at the geometry of the complex. It has been reported in the literature that CHCl3 and CH/D3CN form red-shifting H-bonded complex in Ar matrix. The red shifting has been verified by doing ab initio calculations in the presence of Ar atoms, which has been attributed to the matrix effect at low temperature. The interaction of Ar with CH3CN makes the CH3CN more basic and as a result it becomes better hydrogen bond accep...

Structural deterioration of a soil subjected to freezing-thawing cycles can significantly influence its engineering performances. The nuclear magnetic resonance (NMR) technique provides a powerful tool for studying the structural evolution of water-saturated porous media such as soils. In the present work, three soils were tested under repeated freezing-thawing cycles. The process was monitored by measuring T2 distribution curves, T1-T2 correlation spectra and distributions of log (T1/T2) with NMR technique, and then adsorptive water contents were calculated. The variation of the adsorptive water contents increased as the fraction of sand in the soil increased, implying that the higher the sand content, the more significantly the soil microstructure varied. The T2 distribution curves for soil with sand fraction of 30% did not significantly change, whereas those for soils with higher sand fractions (50% and 70%) were quite different. In addition, Peak 2 changed from a flattened peak to a sharp peak, implying a more uniform microstructure after cyclic freezing-thawing. The peak intensity in T1-T2 correlation spectra changed quite significantly during the freezing-thawing process, implying that the two porosity systems in the soil exchanged water during the process. Significant change of soils usually occurred only in the first 5 freezing-thawing cycles. The microstructure variation for soil with sand fraction of 70% was larger, and then soils with sand fractions of 30% and 50% were less in order, suggesting a ranking of variation degree in agreement with sand fraction.

In this paper, based on the simple model of fiber laser, the transmission characteristics of Akhmediev breathers in fiber laser is studied numerically by the split-step Fourier method. The Akhmediev breathers are influenced by the average dispersion and the small signal gain coefficient in fiber laser. The results show that Akhmediev breathers can be stable transmitted when the average dispersion and nonlinear effects are balanced. The larger the small signal gain coefficient, the peak intensity of Akhmediev breathers is greater with the width narrower. And the spatial separations of the sub-pulses are gradually reduced. In addition, the collision of two breathers can form the localized high-amplitude pulse trains in fiber laser. The results obtained in this paper can provide a theoretical basis for the study of the transmission of Akhmediev breathers in fiber laser.

The optically stimulated luminescence (OSL) and thermoluminescence (TL) signals of an Al2O3:C,Mg single crystal were investigated as a function of the heating temperature and illumination time before readout, respectively. The TL and OSL results were analyzed in complementary ways, including the area under the curve, whole range and partial integration, and peak intensity. A correlation between the continuous decay of the main TL peak intensity (at 185 °C at a heating rate of 1 °C/s) against blue light (470 nm) illumination times and the decay of the OSL signal for higher temperatures was found. Both these results showed that the emptying of the OSL active trap was closely related to the emptying of the trap related to the main TL peak, indicating a correlation of both phenomena.

The present study compared two pH-cycling models designed to induce subsurface lesions (SLs) with a less demineralized surface layer on teeth, with the aim of developing new technologies for assessment of such lesions by examining the performance of confocal Raman microscopy for detection of white spot lesions (WSLs). Twelve sound premolars were exposed to two sets of model conditions (A, B) designed to induce SLs. Teeth on which white lesions had formed in vivo were used as positive controls. All specimens were inspected using an intraoral camera and Raman microscopy to detect small changes in the appearance and structure of the enamel. Changes in the natural color of the teeth during the treatment were recorded via the camera. Phosphate maps with their spectra were constructed from the phosphate peak at 960 cm-1. The depth of lesions was measured on the basis of variations in phosphate peak intensity. Protocol B was reliable for reproducing SLs in a relatively short period. Both protocols had intrinsic limitations in not completely simulating the complex intraoral conditions leading to WSL formation with respect to lesion depth and preservation of an intact surface layer. Raman microscopy can be considered the gold standard for analysis of hard tissue mineralization.

In this work, we have investigated the compensation effect of defects in lightly Si-doped GaN layer. It is found that the compensation of defects can be enhanced by increasing Si doping concentration and dislocation density in GaN layer. Subsequently, through theoretical analysis it is found that a more effective compensation is activated by increasing Si doping, which is mainly due to the enhanced effect of deep defects in the compensation role rather than by the increase of density of deep defects. Meanwhile, it is found that the yellow luminescence (YL) intensity of lightly Si-doped GaN samples increases with the increasing Si doping concentration, which can also be caused by the enhancement of compensation of deep level defects, while the increase of peak intensity of band edge luminescence with increasing Si doping is mainly caused by the increase of free carriers.

Given the growing interest in the application of Raman spectroscopy for quantitative purposes in solid pharmaceutical preparations, a revision of the effect of particle size on Raman spectra of compacted samples is presented. For this purpose, a set of tablets of potassium hydrogen phthalate (KHP) of different particle size were prepared. KHP was used because of its purity and stability, which allow to consider that samples will not be altered during measurements; but also because of its chemical structure (aromatic ring and carboxylic groups), that are present in many active pharmaceutical ingredients (API). The latter makes possible to consider KHP as a model pseudo-API. As KHP tablets only contain a pure compound, the mapping strategy that was considered for measuring our samples will not be affected by subsampling issues. The spectra variance can be attributed to the intrinsically reproducibility in recording the spectra (which mainly depends on the instrument set-up) and the site-to-site differences in elastic scattering properties. Two different instrumental optics have been studied: a macro-Raman system and a Raman microscope (500 μm and 50 μm laser spot size, respectively). The effect of the spectra preprocessing is also evaluated. The overall results demonstrate raw Raman intensity increases with particle size up to a value that depends on tablet width and that the applied spectral preprocessing (baseline correction and a unit vector normalization), reduces the differences in Raman intensities due to the particle size, but does not completely eliminate it for the lower particle sizes (< 20 μm). For tablets containing particles with predefined sizes, it corrects the mapping site-to-site differences in elastic scattering.

—The internal friction in polyethylenes of different grades is studied by the method of relaxation spectroscopy. The relationship between the characteristics of dissipative processes and physical and chemical properties of the studied materials is discussed.

We studied the optical properties of CdTe/ZnTe quantum dots (QDs) in single, double, and triple QD structures by measuring the temperature-dependent photoluminescence (PL). On going from the single to the triple QD structures, the PL peak position of the QDs was blue shifted. This blue-shift was attributed to compressive strain imparted by the separation layers and to material intermixing. Temperature-dependent PL measurements of the triple QD structures showed that, as the temperature increased, the PL peak intensity for the 4.5-monolayer (ML) QDs decreased less than it did for the 3.0- and the 3.5-ML QDs. The activation energy of the 4.5-ML QDs in the triple QD structures was larger than that of the corresponding 4.5-ML QDs in the single QD structures. The reason for this is that, as the temperature increases, some carriers disappear due to non-radiative recombination, but many carriers in the 3.0- and the 3.5-ML QDs move to the 4.5-ML QDs in the triple QD structures, and those carriers then undergo radiative recombination.

Mass spectrometry profiles of microorganisms obtained by time-of-flight matrix-associated laser desorption/ionization (MALDI-TOF) mass spectrometry are a source of information about peptide profiles can be used for microbial identification and typing. A variety of technical and bioinformational solutions complicate developing of a united mass-spectro-profile database. Staphylococcus spp. strains are good studied objects for identification by MALDI-TOF mass spectrometry, frequently resulting in nosocomial infections, especially in immunocompromised patients. Rapid differentiation of nosocomial, multiresistant and highly virulent isolates of Staphylococcus spp. Allows to reduce the lethality in weakened and immunocompromised patients. The study was aimed at assessing comparability and reproducibility of identification and typing results for Staphylococcus spp by MALDI-TOF mass spectrometry. Comparing 292 Staphylococcus spp. isolates in clinical specimens obtained fron the multidisciplinary hospital at the NWSMU im. I.I. Mechnikov was carried out by using MALDI-TOF mass spectrometer BactoSCREEN ID (Litech, Russia) and Bruker Biotyper 3.1 (Bruker GmbH, Germany). Comparability of Staphylococcus spp. identification showed that 95.9%; 12 isolates (4.1%) by “Bruker Biotyper 3.1” and 3 isolates (1.1%) by using “BactoSCREEN ID” were incorrectly identified. Repeated identification leveled the differences between the systems used. In addition, it was shown that the method of protein extraction did not affect reliability of Staphylococcus spp. species identification by using databases (÷2, p 0.05) compared to intraspecific typing (÷2, p 0.0001). Using different extraction protocols showed that Staphylococcus spp. mass-spectra differed by peak intensity level within the mass range up to 4000 m/z, 5300±600 m/z and 6500±500 m/z, as well as higher than 7000 m/z. Peaks of low-molecular weight peptides were detected under full protein extraction compared to sample preparation on plate extraction. To develop a unified protocol for mass-spectrometry profile processing, a reliability of the basic statistical variables (mode, median, maximum, minimum and arithmetic mean) was evaluated. Analysis of the median mass spectrometry profiles is recommended for Staphylococcus spp. intraspecific typing by using MALDI-TOF mass spectrometry as the most reproducible and consistent approach. As a result, two systems for MALDI-TOF mass spectrometry reliably identify Staphylococcus spp., but standardization of sample preparation and bioinformation analysis is required for Staphylococcus spp. typing.

Thermoluminescence of a high temperature secondary glow-peak in natural quartz annealed at 900 °C is reported. The glow-curve of a sample irradiated to 10 Gy and measured at 1 °C/s shows three peaks; the main peak at 71 °C and two other weaker-intensity peaks at 125 °C and 177 °C. For reference, the peaks are labelled as I, II and III. This study is concerned with the secondary peak at 177 °C (peak III). The electron trap responsible for peak III is stable at ambient temperature as determined by monitoring the peak intensity after various delays between irradiation and measurement. The activation energy and frequency factor of the peak were estimated as ~1.24 eV and ~1012 s−1 respectively. The dose response of the peak in the range 1–300 Gy is sublinear. The influence of either partial heating or irradiation dose on the peak position suggest that the peak follows non-first-order kinetics.

The aim of this investigation was to determine the position and duration specific activity of the most demanding passages of play in football players. Global positioning system data were collected from twenty-three football players across a competitive season. A total of 605 individual match files were analysed. Players were categorised based on positional groups; full-back (FB), central defender (CD), midfielder (MF), wide midfielders (WMF) and forwards (FW). The most demanding passage of a match play was analysed using a rolling average method, where maximal values were calculated for four different time durations (1’, 3’, 5’ and 10’) using distance (m·min-1), high metabolic load distance (HMLD) and average metabolic power (AMP) as variables of interest. Using distance as the criterion variable, MF and WMF positions covered greater distance, and fewer sprinting meters (>7.0 m·s-1, m·min-1). With HMLD as the criterion variable, the values for WMF and MF positions were higher than the CD and FW positions. The MF and WMF positions performed more high-intensity accelerations and decelerations when the criterion variable was AMP. These results provide an understanding of the most demanding passages of play to inform training practices for specific football playing positions.

Although incremental dynamic analysis (IDA) can be regarded as an accurate tool for evaluating seismic capacity of structures, it is very time intensive. Generating IDA curves requires performing multiple nonlinear time-history analyses (NTHA) for given earthquake records. In this paper, a new algorithm based on Fibonacci sequence is developed for finding the maximum intensity measure (IM) under which the structure’s dynamic response is numerically stable. It is shown that, by performing a very limited number of evaluations, the method can locate this point with the desired accuracy even if the IDA curve is not unimodal. Once the maximum IM is found, the whole IDA curve can be obtained by performing a few more NTHAs. Since the proposed method can be regarded as an optimal approach for establishing the IDA curves, it can be efficiently used in optimization problems in which objective functions or the constraints are related to IDA analyses.

Purpose This work proposes a semiempirical correction method for attenuation of x-ray fluorescence (XRF) photons and/or an excitation beam during direct XRF imaging (i.e., mapping) of gold nanoparticle (GNP) distribution utilizing gold L-shell XRF photons. Methods The current method was first devised by finding the two following relationships: (a) ratio of gold XRF peak intensity (Lα at ~9.7 keV and Lβ at ~11.4 keV) vs pathlength of XRF photons; (b) XRF photon counts produced (Nxrf ) vs scattered photon counts produced (Nscat ). Monte Carlo simulations were performed using the Geant4 tool kit to characterize the aforementioned relationships for different tissue-like media. The applicability of the method was tested experimentally by acquiring 2D L-shell XRF images of custom-made phantoms using an experimental benchtop x-ray fluorescence computed tomography setup. Results The results show that the ratio of gold L-shell XRF peak intensities allowed an estimation of the pathlength of XRF photons, thus can be utilized to correct for attenuation of XRF photons after emission. The results also demonstrate that Nscat , through a proportionality N xrf ∝ N scat T where the exponent T depends on the energy of scattered photons, could be used to correct for attenuation of an excitation beam prior to producing XRF photons. The corrected XRF signal was found independent of the densities of tissue-like media present along the passage of an excitation beam or emitted XRF photons. Conclusions The current results suggest that the developed attenuation correction method plays an essential role for the detection of GNPs on the order of parts-per-million, and also for the determination of GNP concentration/location within the imaging object made of tissue-like media, without any prior knowledge of the imaging object shape, under the conditions deemed relevant to biomedical applications of gold L-shell XRF-based imaging.

Nanodiamonds (NDs) have been synthesized by using microplasma facility. Ethanol is chosen as a Carbon precursor. A mixture of Ethanol and Argon has been dissociated in microplasma to fabricate NDs. In order to quench, etch and stabilize the NDs, Hydrogen has been used as a stabilizing agent. The motivation behind this project is to find an effective root for the introduction of Hydrogen into microplasma. The experiments are performed by introducing the Hydrogen either directly or indirectly into the microplasma. The results obtained from Raman, TEM and XRD confirmed that the highest quality (in terms of smallest size and near stress free) diamonds have been obtained in the case of indirect dilution. The decreased PL peak intensity with indirect dilution indicates the decreased defect density in the diamond. It is possible to produce and control the defect center only by controlling the Hydrogen introduction way in to the microplasma. The indirect dilution decreases the amount of Hydrogen bonded to trans-polyacetylene and enhances the Hydrogen termination to the surface of diamond grains.

The tentative identification of bioactive compounds in the extract of Vernonia amygdalina leaf was carried out using positive ionization of Liquid chromatography-mass spectrometry quadrupole time of flight (LC-Q-TOF/MS). The positive ionization is associated with the presence of saponins, flavonoids, alkaloids, terpenoids, and glycosides. Tentative assignments of the secondary metabolites were performed by comparing the MS fragmentation patterns with Waters® UNIFY library which allows positive identification of the compounds based on the spectral match. All the metabolites compounds were estimated and presented in a BPI (Base peak intensity) plot. These data are the unpublished supplementary materials related to “Ethanolic extraction of bioactive compounds from V. amygdalina leaf using response surface methodology as an optimization tool” (Alara et al., 2018).

In the current study the association rate between solar energetic particles (protons) and filaments and/or filament eruptions (FEs) is investigated using the largest reported event sample. Proton events observed in the period 2010–2016 are accompanied by filaments in 92% (143/156) of the cases. Due to the lack of comprehensive catalog of all filaments, a catalog of FEs is used for the reversed association. Only 5% of FEs have in situ proton signatures with larger peak intensity, compared to the median of the entire proton sample. Other solar activity phenomena (flares and coronal mass ejections) related to the proton events show differences in their distributions compared to the respective FE-samples. The indication for a shock wave formation using the type II radio signatures is also considered and discussed.

This investigation aimed to compare the international level peak intensity period of male field hockey players to those experienced during professional and amateur club hockey match play. Twenty-seven players from an international squad were monitored for all activity relating to field hockey over three seasons. The peak intensity period, of 3 min duration, was extracted from match play files for international and club matches. Club matches were categorised by league standard—professional vs. amateur. The output for the peak intensity period, within positions, was compared using linear mixed models (LMMs) and post hoc pairwise comparisons. Significance levels were set as p &lt, 0.05 and Cohen’s d was utilised for effect sizes. Competition level had a main effect on relative total distance (p &lt, 0.05) and significant interaction effects were found between competition level and position (p &lt, 0.05). Midfielders competing in amateur leagues and international match play completed less relative total distance than those who compete in professional leagues (−47.88 m/min, p &lt, 0.05), (−46.06 m/min, p &lt, 0.05) with large effect sizes reported. No other position displayed significant differences for peak periods. Match play in professional leagues provide opportunities for midfielders to experience peak intensity periods of a greater magnitude than international match play.

Antibiotic resistant bacteria pose an increasing threat to global public health, and it is essential that effective detection methods for identifying these organisms. This study assesses the ability of three different analytical approaches that were developed using surface-enhanced Raman spectroscopy (SERS) to differentiate between antibiotic sensitive and resistant bacteria based on their responses to ampicillin exposure, using Escherichia coli O157:H7 as a model bacterium. The approaches tested in this study included a conventional SERS approach of mixing a droplet of bacterial culture with gold nanoparticles, extracellular matrix analysis, and in situ mapping of bacterial cells on a filter membrane. All three of the SERS techniques were able to differentiate between the sensitive and resistant bacterial strains based on peak intensity changes associated with compounds released by the bacteria in response to antibiotic exposure, with extracellular matrix analysis and filter mapping both observed to be more effective than the conventional approach. However, there were significant differences between the spectra obtained from the different techniques and the potential advantages and disadvantages of each approach should be considered when used in the future. This study shows that SERS can be an effective technique for rapid and efficient assessment of ampicillin sensitivity in E. coli, and more work should be done to explore these analytical approaches with other types of bacterial samples.

Background The antitumor effect of a drug is considered to be associated with a decrease in tumor blood flow. Aims We investigated whether the efficacy of lenvatinib (LEN) could be accurately assessed by measuring blood flow in hepatocellular carcinoma (HCC) during early treatment stages. Methods and results Blood flow changes and treatment results of 19 patients who underwent contrast-enhanced ultrasound (CEUS), before and after LEN administration, in Kurume University Hospital from July 2018 to June 2020 were examined. Blood flow was evaluated after the intravenous administration of perflubutane (0.015 ml/kg). The vascular phase was photographed and used as RAW data, and time-intensity curve analysis was used to obtain the region of interest (ROI) on the entire tumor nodule and quantify tumor blood flow. The evaluation was performed before and 1 and 4 weeks after LEN administration. Mean ± standard deviation (SD) values of the brightness of blood flow in the background liver before and 1 and 4 weeks after LEN administration were 2.84 × 10-4 ± 2.94 × 10-4 , 3.07 × 10-4 ± 3.79 × 10-4 , and 10.0 × 10-4 ± 20.8 × 10-4 dB, respectively. Blood flow in the background liver did not significantly decrease at 1 and 4 weeks compared with that before treatment. Mean ± SD values of the brightness of blood flow in HCC before and 1 and 4 weeks after administration were 3.49 × 10-3 ± 4.58 × 10-3 , 1.16 × 10-3 ± 1.57 × 10-3 , and 6.39 × 10-3 ± 22.8 × 10-3 dB, respectively. Blood flow in HCC after 1 week was significantly lower than that before administration (p = .0192). The therapeutic effects were significantly higher in the group with ≥50% blood flow reduction in HCC at 1 week after administration (p = .0038) and the group with reduced blood flow in HCC at 4 weeks after administration (p = .0051) than those before administration. Conclusion Early blood flow evaluation by CEUS may be useful in predicting the therapeutic effect of LEN for unresectable advanced HCC.

Rationale Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) is a preferred technique for analyzing complex organic mixtures. Currently, there is no consensus normalization approach, nor an objective method for selecting one, for quantitative analyses of FT-ICR-MS data. We investigate a method to evaluate and score the amount of bias various normalization approaches introduce into the data. Methods We evaluate the ability of the Statistical Procedure for the Analysis of Normalization Strategies (SPANS) to guide the selection of appropriate normalization approaches for two different FT-ICR-MS data sets. Furthermore, we test the robustness of SPANS results to changes in SPANS parameter values and assess the impact of using various normalization approaches on downstream statistical analyses. Results The normalization approach identified by SPANS differed for the two data sets. Normalization methods impacted the statistical significance of peaks differently, underscoring the importance of carefully evaluating potential methods. More consistent SPANS scores resulted when at least 120 significant peaks are used, where larger sets of peaks were obtained by increasing the p-value threshold. Interestingly, we show that total sum scaling and highest peak normalization, used in previous studies, underperformed relative to SPANS-recommended normalization approaches. Conclusions Although there is no single, best normalization method for all data sets, SPANS provides a mechanism to identify an appropriate normalization method for analyzing FT-ICR-MS data quantitatively. The number of peaks used in the background distributions of SPANS contributes more significantly to the reproducibility of results than the p-value thresholds used to obtain those peaks.

An accurate estimate of precipitation is essential to improve the reliability of hydrological models and helps for decision-making in agriculture and economy. Merged radar–rain-gauge products provide precipitation estimates at high spatial and temporal resolution. In this study, we assess the ability of the INCA (Integrated Nowcasting through Comprehensive Analysis) precipitation analysis product provided by ZAMG (the Austrian Central Institute for Meteorology and Geodynamics) in detecting and estimating precipitation for 12 years in southeast Austria. The blended radar–rain-gauge INCA precipitation analyses are evaluated using WegenerNet – a very dense rain gauge network with about 1 station per 2 km2 – as true precipitation. We analyze annual, seasonal, and extreme precipitation of the 1 km × 1 km INCA product and its development from 2007 to 2018. Based on the results, the performance of INCA can be divided into three different periods. From 2007 to 2011, the annual area-mean precipitation in INCA was slightly higher than WegenerNet, except in 2009. However, INCA underestimates precipitation in grid cells farther away from the two ZAMG meteorological stations in the study area (which are used as input for INCA), especially from May to September (wet season). From 2012 to 2014, INCA's overestimation of the annual-mean precipitation amount is even higher, with an average of 25 %, but INCA performs better close to the two ZAMG stations. From 2015 onwards, the overestimation is still dominant in most cells but less pronounced than during the second period, with an average of 12.5 %. Regarding precipitation detection, INCA performs better during the wet seasons. Generally, false events in INCA happen less frequently in the cells closer to the ZAMG stations than in other cells. The number of true events, however, is comparably low closer to the ZAMG stations. The difference between INCA and WegenerNet estimates is more noticeable for extremes. We separate individual events using a 1-hour minimum inter-event time (MIT) and demonstrate that INCA underestimates the events' peak intensity until 2012 and overestimates this value after mid-2012 in most cases. The overestimation of the peak-intensity is more pronounced during July. In general, the precipitation rate and the number of grid cells with precipitation are higher in INCA. Furthermore, 40 % of the individual events start earlier, and 50 % end later in INCA. Considering four extreme convective short-duration events, there is a time shift in peak intensity detection. The relative differences in the peak intensity in these events can change from approximately −40 % to 40 %. The results of this study can be used for further improvements of INCA products as well as for future hydrological studies in this area.

BackgroundUnderstanding the differences in timing and composition of physical distancing policies is important to evaluate the early global response to COVID-19. A physical distancing intensity framework comprising 16 domains was recently published to compare physical distancing approaches between U.S. States. We applied this framework to a diverse set of low and middle-income countries (LMICs) (Botswana, India, Jamaica, Mozambique, Namibia, and Ukraine) to test the appropriateness of this framework in the global context and to compare the policy responses in this set of LMICs and with a sample of U.S. States during the first 100-days of the epidemic.ResultsAll six of the LMICs in our sample adopted wide ranging physical distancing policies. The highest peak daily physical distancing intensity in each country was: Botswana (4.60); India (4.40); Ukraine (4.40); Namibia (4.20); and Jamaica (3.80). The number of days each country stayed at peak intensity ranged from 12-days (Jamaica) to more than 67-days (Mozambique). We found some key similarities and differences, including substantial differences in whether and how countries expressly required certain groups to stay at home. We also found that the LMICs generally implemented physical distancing policies when there were few confirmed cases and the easing of physical distancing policies did not discernably correlate with change in COVID-19 incidence. The physical distancing responses in the LMIC sample were generally more intense than in a sample of U.S. States, but results vary depending on the U.S. State. For example, California had a peak intensity of 4.29, which would place California below the peak intensity for Botswana, India, and Ukraine but above Mozambique, Namibia and Jamaica. The U.S. State of Georgia had a peak intensity of 3.07, which would place it lower than all of the LMICs in this sample. The peak intensity for the U.S. 12-state average was 3.84, which would place it lower than every LMIC in this sample except Jamaica.ConclusionThis analysis helps to highlight the differing paths taken by the countries in this sample and may provide lessons to other countries regarding options for structuring physical distancing policies in response to COVID-19 and future outbreaks.

People are good at categorizing the emotions of individuals and crowds of faces. People also make mistakes when classifying emotion. When they do so with judgments of individuals, these errors tend to be negatively biased, potentially serving a protective function. For example, a face with a subtle expression is more likely to be categorized as angry than happy. Yet surprisingly little is known about the errors people make when evaluating multiple faces. We found that perceivers were biased to classify faces as angry, especially when evaluating crowds. This amplified bias depended on uncertainty, occurring when categorization was difficult, and it reached peak intensity for crowds with four members. Drift diffusion modeling revealed the mechanisms behind this bias, including an early response component and more efficient processing of anger from crowds with subtle expressions. Our findings introduce bias as an important new dimension for understanding how perceivers make judgments about crowds. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Spontaneous Raman spectroscopy, which senses changes in cellular contents of reduced cytochrome c, could be a powerful tool for label-free evaluation of ischemic hearts. However, undetermined is whether it is applicable to evaluation of myocardial viability in ischemic hearts. To address this issue, we investigated sequential changes in Raman spectra of the subepicardial myocardium in the Langendorff-perfused rat heart before and during ligation of the left coronary artery and its subsequent release and re-ligation. Under 532-nm wavelength excitation, the Raman peak intensity of reduced cytochrome c at 747 cm-1 increased quickly after the coronary ligation, and reached a quasi-steady state within 30 min. Subsequent reperfusion of the heart after a short-term (30-min) ligation that simulates reversible conditions resulted in quick recovery of the peak intensity to the baseline. Further re-ligation resulted in resurgence of the peak intensity to nearly the identical value to the first ischemia value. In contrast, reperfusion after prolonged (120-min) ligation that assumes irreversible states resulted in incomplete recovery of the peak intensity, and re-ligation resulted in inadequate resurgence. Electron microscopic observations confirmed the spectral findings. Together, the Raman spectroscopic measurement for cytochrome c could be applicable to evaluation of viability of the ischemic myocardium without labeling.