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The exploitation of offshore wind resources is a crucial step towards a clean energy future. It requires an advanced approach for high-resolution wind resource evaluations. We explored the suitability of the Sentinel-1 Level-2 OCN ocean wind field (OWI) product for offshore wind resource assessments. The SAR data were compared to in situ observations and three reanalysis products: the global reanalysis ERA5 and two regional reanalyses CARRA and NORA3. This case study matches 238 scenes from 2022 for the Goliat station, an oil platform located 85 km northwest of Hammerfest in the Barents Sea, where a new offshore wind park has been proposed. The analysis showed that despite their unique limitations in spatial and temporal resolutions, all data sources have similar statistical properties (RMSE, correlation coefficient, and standard deviation). The Weibull parameters characterizing the wind speed distributions showed strong similarities between the Sentinel-1 and all reanalysis data. The Weibull parameters of the in situ measurements showed an underestimation of wind speed compared to all other sources. Comparing the full reanalysis datasets with the subsets matching the SAR scenes, only slight changes in Weibull parameters were found, indicating that, despite its low temporal resolution, the Sentinel-1 Level 2 OWI product can compete with the more commonly used reanalysis products in the estimation of offshore wind resources. Its high spatial resolution, which is unmatched by other methods, renders it especially valuable in offshore areas close to complex coastlines and in resolving weather events at a smaller scale. [ABSTRACT FROM AUTHOR]

In the framework of the work the description of sphere wave filed in the far observation region is discussed. The consideration is based on the decomposition of the wave field over the longitudinal and transverse spatial parameters of the problem in the direction of observation. It is shown that the approximation of a sphere wave by the flat field is correct only if the consideration is conducted in the limit of solid angle. The magnitude of the solid angle, which includes the area of flatness of the spherical wave, is determined using the so-called wave parameters corresponding to the observation area and the illuminated point. The wave field created by a small flat area is defined as a limit case of a superposition field generated by a system of point sources. It is shown that in an observation point the wave field of a small flat area can be characterized by the angle between the area normal and the vector indicting from the given area the observation point. The problem of description of a wave filed in the framework of a small flat aria is also discussed. A new method for deriving of the well-known obliquity factor of the Kirchhoff diffraction theory is suggested. [ABSTRACT FROM AUTHOR]

The well-known Laue condition determining the intensity maximums of diffracted on an ideal crystal structure plane wave is discussed. It is proved that the Laue conditions, which are restrictions imposed on the values of the scattering wave vector, is more correctly to be considered as a pair of two conditions. The first conditions relate to the wave vector of an incident wave and the second conditions relate to the wave vector of an observation direction. In other words, to observe the maximums, it is not enough that only the difference (the scattering wave vector) of these two vectors satisfies the Laue condition. To observe the maximums, it is necessary that each of these vectors separately, i.e. the wave vector of the incident wave and the wave vector of the observation direction, satisfy the Laue condition. It is shown that such a doubling of the maximums conditions leads to a decrease in the number of observed maximums compared to the condition imposed only on the scattering wave vector. [ABSTRACT FROM AUTHOR]

The automatic detection and analysis of ocean eddies in the marginal ice zone via remote sensing is a very challenging task but of critical importance for scientific applications and anthropogenic activities. Therefore, as one of the first steps toward the automation of the eddy detection process, we investigated the potential of applying YOLOv5, a deep convolutional neural network architecture, to specifically collected and labeled high-resolution synthetic aperture radar data for a very dynamic area over the Fram Strait. Our approach involved fine-tuning pre-trained YOLOv5 models on a sparse dataset and achieved accurate results with minimal training data. The performances of the models were evaluated using several metrics, and the best model was selected by visual examination. The experimental results obtained from the validation and test datasets consistently demonstrated the robustness and effectiveness of the chosen model to identify submesoscale and mesoscale eddies with different structures. Moreover, our work provides a foundation for automated eddy detection in the marginal ice zone using synthetic aperture radar imagery and contributes to advancing oceanography research. [ABSTRACT FROM AUTHOR]

The problem of an approximate description of the wave field of many sources is considered. It is shown that, if the problem is considered more comprehensively, the description of the interference and diffraction experiments can be given within the framework of a single scheme. It is shown that the character of wave amplification in these two classical experiments is different. In the case of an interference experiment, the field amplification is fixed at a point, while in the case of a diffraction experiment the field amplification is fixed in the observation direction. The problem of determining the intensity maximum of a diffraction grating in the Fresnel pattern is studied under the condition that the maximum is satisfied in the Fraunhofer pattern. A condition under which a diffraction grating behaves like a lens is obtained. [ABSTRACT FROM AUTHOR]

The most common source of information about sea ice conditions is remote sensing data, especially images obtained from synthetic aperture radar (SAR) and passive microwave radiometers (PMR). Here we introduce an adaptive fusion scheme based on Graph Laplacians that allows us to retrieve the most relevant information from satellite images. In a first test case, we explore the potential of sea ice classification employing SAR and PMR separately and simultaneously, in order to evaluate the complementarity of both sensors and to assess the result of a combined use. Our test case illustrates the flexibility and efficiency of the proposed scheme and indicates an advantage of combining AMSR‐2 89 GHz and Sentinel‐1 data for sea ice mapping. Plain Language Summary: The Earth's land and ocean surface is monitored from space using different sensors mounted on various satellite platforms. Each type of sensor has its advantages and limitations. Combining data from different sensors can potentially solve ambiguities in information retrievals associated with the use of only a single sensor. Here, we apply a multi‐sensor fusion scheme that can be used for various data combinations in order to extract relevant information. The main goal of this work is to explore the potential of simultaneously applying two sensors for sea ice mapping and monitoring, namely synthetic aperture radar and passive microwave radiometers, in order to improve the separation of sea ice types. Key Points: We propose an adaptive scheme for the fusion of passive microwave radiometers and synthetic aperture radar data for sea ice classificationWe demonstrate the flexibility and efficiency of the proposed scheme on a test case by evaluating the performance of various data scenariosWe illustrate the advantages and limitations of applying the data of each sensor simultaneously and separately [ABSTRACT FROM AUTHOR]

A new method for solving ordinary differential equations is suggested. As it is shown the deferential equation can be solved not only by means integration of its differentiation as well. It is shown that the differential equation can be solved not only by integration, but also by differentiation. The developed method is applied for consideration of corresponding equations for the exponential function and trigonometric functions. In the framework of the developed method the simple approach for derivation of Taylor series of a function is demonstrated. Based imminently on the geometric definition the connections between trigonometric functions and their derivatives are obtained as well. The well-known Euler formula is also produced, which establishes a connection between trigonometric functions and exponential function. [ABSTRACT FROM AUTHOR]

The paper discusses the problem of a superposition wave field created by a system of coherent point sources. For the general case, the conditions for a point amplification of the superposition field are found. The focusing problem is discussed for a system of point sources located on circles with centers lying on the same straight line parallel to the planes of the circles. [ABSTRACT FROM AUTHOR]

The paper considers the problem of an approximate wave field in the so-called near, middle and far zones of observation. The possibility of introducing a more accurate than the Fresnel approximation, the so-called quasi-exact approximation, is indicated. For the interference problem usually considered in the Fresnel approximation, the intensity distribution in the near field of observation is obtained. It is shown that the positions of intensity maxima in the near zone of observation are determined by a cubic equation. [ABSTRACT FROM AUTHOR]

The article deals with theoretical aspects of human capital, features of human capital, problems and prospects of human capital in modern conditions. Problems and challenges of ontology and functioning of human capital in postmodern society are outlined. The current state of investment in the reproduction of human capital and its development was assessed. One of the ways to increase human capital is to invest in people, their health and education. The article substantiates the role and importance of investments in human capital at the family level. The sharp increase in interest in the creative abilities of a person and in the ways of their formation and development confirm the obtained results. The international significance of the article lies in the objectification of the problems of human capital in developing countries (using the example of Ukraine), taking into account the global industrial, cultural and social context. In order to optimize human capital management on the verge of the postmodern and post-post era, these research results can help in the development of scientific, public and government programs and activities. [ABSTRACT FROM AUTHOR]

Pulsed-laser testing is used to accurately determine single-event latchup (SEL) thresholds for static random-access memories (SRAMs) with different body-tie-to-drain spacings on a mixed-signal application-specific integrated circuit (ASIC), a study that could not be completed using only broad-beam heavy-ion testing. Two distinct approaches were employed with the first approach, an empirical correlation method, exploiting the complementary nature of broad-beam heavy-ion and laser testing. Various single- and dual-port SRAMs exhibited SEL thresholds ranging from 1 MeV-cm2/mg to over 100 MeV-cm2/mg, with a dual-port device possessing the smallest body-tie-to-drain spacing being latchup immune at the highest available test conditions (>300 MeV-cm2/mg). These results have been used to inform a follow-on ASIC design resulting in a significant improvement in chip-level SEL sensitivity. The second approach, a calculational method, uses pulsed-laser measurements and charge-deposition modeling to predict linear energy transfer (LET) thresholds without heavy-ion data. This calculational approach agrees with the empirical approach and therefore shows promise as a predictive tool for SEL threshold estimation, but further validation is required. Overall, these approaches can be effective tools for evaluating SEL susceptibilities and mitigation strategies. [ABSTRACT FROM AUTHOR]

In this work, we describe the synthesis, interactions with bovine serum albumin, and cytotoxicity of new ionic liquids based on 5-fluorouracil (API-ILs) with different cations (imidazolium, choline, isoquinolinium, guanidinium). The secondary and tertiary structure of BSA in solutions with different concentrations of API-ILs was monitored by the circular dichroism (CD) technique. The addition of API-ILs does not lead to structural changes in BSA. A quenching of fluorescence spectra intensity of BSA in presence of all API-ILs was observed, allowing the quantification of binding between API-ILs and BSA. The preferred localization of both ions in API-ILs differs significantly depending on the structure of the cation according to molecular docking. The aggregation of BSA in presence of API-ILs was analyzed by the dynamic light scattering (DLS) method, revealing a moderate increase in particle size. Cytotoxicity and selectivity of API-ILs on cancer and normal cell lines were estimated, showing a clear modification of the pharmaceutic activity of ionic liquid compared to 5-fluorouracil. [ABSTRACT FROM AUTHOR]

By scanning the charge-deposition profile produced by a pulsed laser throughout a device, the spatially dependent charge-collection efficiency (CCE) can be determined. This is demonstrated by extracting the depth-dependent CCE in two photodiodes. The resulting collection efficiency curves are found to be consistent with their device structures and the expected charge-collection mechanisms. By applying the efficiency curves to the charge-deposition curves for both heavy ions and pulsed X-rays, the calculated collected charge values show very good agreement with experimental results. This suggests that the profiles extracted using the laser can help predict charge-collection data from other excitation sources and could improve modeling efforts by determining sensitive volumes. [ABSTRACT FROM AUTHOR]

A general theory for description of a wave packet evolution in the field of one-dimensional potential is developed. Based on the method of counter propagating waves it is shown that the evolving wave can be presented as a sum of three terms. The first one corresponds to the wave motion along the positive direction and the second one describes the wave motion along the negative direction. The third term defines the interference between the counter propagating waves. It is proofed that when the center of the carrier energy of the wave packet equals to the resonant tunneling energy then the motions of counter propagating waves separately take place. [ABSTRACT FROM AUTHOR]

Abstract: A general theory for description of a wave packet evolution in the field of one-dimensional potential is developed. Based on the method of counter propagating waves it is shown that the evolving wave can be presented as a sum of three terms. The first one corresponds to the wave motion along the positive direction and the second one describes the wave motion along the negative direction. The third term defines the interference between the counter propagating waves. It is proofed that when the center of the carrier energy of the wave packet equals to the resonant tunneling energy then the motions of counter propagating waves separately take place. [ABSTRACT FROM AUTHOR]

The present work is devoted to the thermochemical study of solvation of ionic liquids (IL) in benzene. The solution enthalpies of 1-ethyl-3-methylimidazolium tricyanomethanide [EMIM][C(CN)3], 1-butyl-3-methylimidazolium tetrafluoroborate [BMIM][BF4], 1-hexyl-3-methylimidazolium hexafluorophosphate [HMIM][PF6], 1-octyl-3-methylimidazolium tetrafluoroborate [OMIM][BF4], 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [EMIM][NTf2], 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [BMIM][NTf2] and 1-butyl-3-methylimidazolium trifluoromethanesulfonate [BMIM][TfO] in benzene were measured. The solvation enthalpies of imidazolium-based IL were calculated. Molar refractions of imidazolium-based IL form literature data on density and refractive indexes of IL were also calculated. The linear correlation between solvation enthalpy and molar refraction of IL was observed. This correlation can be used to calculate the vaporization enthalpy of imidazolium-based IL from solution calorimetry data. [ABSTRACT FROM AUTHOR]

Speaking about the oblique Talbot effect, one usually assumes the case when the diffraction grating is illuminated by a plane wave at an angle, while the screen for observing the diffraction pattern is located parallel to the plane of the diffraction grating. At the same time, as the presented consideration shows, if the grating is illuminated at an angle, then in order to observe the Talbot effect, the observation screen must be tilted as well. In the present work, we considered the inclined Talbot effect for a grating with a finite number of slits, when the observation of the diffraction pattern and the illumination of the grating are performed at an angle. The dependence of the Talbot length on the angles of observation and illumination is determined. It is shown that the effect of self-reproduction can be observed only at certain values of these angles. It is proved that the value of the Talbot length does not depend on the parity of the number of lattice slits. At the same time, the number of slits determines the character of the distribution of maximums on the screen. Thus, in the case of a diffraction grating with an even number of slits, a maximum is observed in the center of the screen. In the case of a grating with an odd number of slits, the pattern of maximums is shifted by half the period of the grating compared to the pattern of maximums in the case of gratings with an even number of slits. [ABSTRACT FROM AUTHOR]

The S(1D)+D2→SD+D reaction has been studied through a photolysis-probe experiment in a cell. S(1D) reagent was prepared by 193 nm photolysis of CS2, and the SD(X 2Π) product was detected by laser fluorescence excitation. The nascent rotational/fine-structure state distribution of the SD(X 2Π) product was determined. This reaction, previously studied theoretically and in a crossed molecular beam experiment, is known to proceed through formation and decay of a long-lived collision complex involving the deep well in the H2S ground electronic state. The determined SD rotational state distribution in the v=0 vibrational level was found to be approximately statistical, with a small preference for formation of the F1 (Ω=3/2) fine-structure manifold over F2 (Ω=1/2). The branching into the Λ doublet levels was also investigated, and essentially equal populations of levels of A′ and A″ symmetry were found. The present results are compared with previous investigations of this reaction and the analogous O(1D)+D2 reaction. © 2005 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Phase lag spectroscopic measurements are performed for HI and DI in the 5d(π, δ) resonance region. Measurements of the phase lags for both molecules reveals a strong isotopic effect, especially pronounced in the ionization channel. The energy dependence of the phase lag provides clear examples of continuum and resonance coupling effects that were previously predicted theoretically but have not yet been observed. It is demonstrated that phase lag spectroscopy is a sensitive technique for studying properties of molecular continua, furnishing information that is not available from phase-insensitive observables. [ABSTRACT FROM AUTHOR]

Receptive field sizes of visually sensitive neurons in cortical centers are dynamic, mainly expanding at the application of moving visual stimuli. The results of experiments presented in this study show, that visually driven neurons in subcortical centers also have dynamic RFs sizes in relation to the applied visual stimulus. Visually sensitive neurons of the subcortical pretectal region reveal substantial modulations of RF sizes at the application of visual stimuli moving in different orientations, which resulted in strong diversification and more precise processing of incoming visual information. [ABSTRACT FROM AUTHOR]

A focused pulsed X-ray beam is used to determine how the redistribution of the electric field by the gate-connected field plate affects single-event transient (SET) susceptibility of an AlGaN/GaN Schottky-gate HEMT on SiC. SETs generated by scanning the X-ray beam across the HEMT depend strongly on the presence of the field plate, radiation strike location, bias conditions, and X-ray photon energy. For the particular HEMT we tested, the gate-connected field plate reduces the electric-field strength near the edge of the gate by a factor of approximately 2, which results in faster decaying transients and less collected charge. [ABSTRACT FROM AUTHOR]

Orientation sensitive properties of extrastriate area 21a neurons were investigated. Special attention was paid to the spatial characteristics of the neuron receptive fields (RF) to the different orientations of visual stimulus motion across neuron RF, defined by presentation of stationary visual stimuli. The results of provided experiments have shown that the neuron RF spatial dimensions undergo essential modulations concerning different orientations of applied visual stimuli. As a result, a high degree of diversification of neuronal response patterns depending of the orientation of moving stimuli was observed. Thus, the processing of visual information in the course of visual image recognition is realized by integrated activity of surrounding cortical networks of visually sensitive neurons. [ABSTRACT FROM AUTHOR]

Focused, pulsed X-rays are used to generate single-event transients (SETs) in metal–insulator–semiconductor (MIS)-gate AlGaN/GaN high-electron-mobility transistors (HEMTs) in order to investigate the mechanisms responsible for SETs. Unlike Schottky-gate GaN HEMTs, where current flows between gate and drain when the device is biased “OFF,” for the MIS-gate HEMTs, current flows between the source and drain. The presence of the SiNx insulating layer under the gate effectively blocks electrons on the gate from moving into the semiconductor. Short-duration SETs at the gate are caused by the collection of holes injected by the X-rays. SETs collected at the source and drain have an initial short-duration component, followed by a long-duration tail that can last for hundreds of nanoseconds. The long tails are due to positive charges (holes) that are less mobile than the electrons and so take longer to exit the HEMT, and to holes that become trapped at defects in the material. The holes lower the potential barrier between the source and the region under the gate, allowing for the injection of electrons that flow from the source to the drain. The durations of the SET tails are determined by the lifetimes of the trapped holes that are found to vary with X-ray photon energy and electrical bias. [ABSTRACT FROM AUTHOR]

Abstract The thermochemical study of hydrogen bonding of organic solutes in 1-methylimidazolium bis(trifluoromethylsulfonyl)imide ([MIM][NTf 2 ]) was carried out. Activity coefficients at infinite dilution of organic compounds in [MIM][NTf 2 ] were measured by gas-liquid chromatography at different temperatures between 303.15 and 343.15 K. The solution enthalpies of organic solutes in [MIM][NTf 2 ] were determined from the temperature dependence of activity coefficients in the same systems. Solution enthalpies of solutes (propanol-1, meta -cresol, acetone, acetonitrile, diethyl ether, tetrahydrofuran, dichloromethane, trichloromethane, pyrrole) in 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [BMIM][NTf 2 ] were measured by using high-precision solution calorimetry. The hydrogen bond enthalpies of organic solutes in [MIM][NTf 2 ] and [BMIM][NTf 2 ] were calculated using a previously developed method. The hydrogen bond enthalpies of organic solutes in the protic ionic liquid [MIM][NTf 2 ] were compared with the values in the aprotic ionic liquid [BMIM][NTf 2 ], as well as with those in the molecular solvent pyrrole. The hydrogen bond enthalpies of proton acceptor molecules in [MIM][NTf 2 ] differ significantly from zero unlike in [BMIM][NTf 2 ]. Hydrogen bond enthalpies of proton acceptor molecules in [MIM][NTf 2 ] and pyrrole are close. Graphical abstract Unlabelled Image Highlights • Activity coefficients of organic solutes in [MIM][NTf 2 ] at five temperatures were measured. • The hydrogen bond enthalpies of proton acceptor solutes in [MIM][NTf 2 ] were determined. • Solution enthalpies of solutes in [BMIM][NTf 2 ] were measured by solution calorimetry. • The N H fragment of [MIM][NTf 2 ] and pyrrole exhibits similar proton donor ability. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The solution enthalpies of water in ionic liquids were measured. • The specific interaction enthalpies of water and methanol in ionic liquids were calculated. • The specific interactions enthalpies of water and methanol in ionic liquids are treated as 2:1. Abstract The thermochemical study of hydrogen bonding of water with different proton acceptor ionic liquids was carried out. Along with the available experimental data, the solution enthalpies of water in [BMIM][TfO], [BMIM][BF 4 ] and [BMIM][PF 6 ] were measured. The hydrogen bonding enthalpies of water with various ionic liquids were determined by using previously developed method of solvation enthalpy separation into the nonspecific solvation enthalpy and the specific solute-solvent interaction enthalpy (hydrogen bonding). The findings indicate the formation of a complex, where one molecule of water is bound to two molecules of ionic liquids. Similarly, hydrogen bonding enthalpies of methanol with the same proton acceptor ionic liquids were determined. [ABSTRACT FROM AUTHOR]

This work is devoted to the quantitative study of hydrogen bond formation of N -alkyl substituted ionic liquids with proton acceptor and proton donor organic solvents. 1-Butyl-3-methylimidazolium bis (trifluoromethanesulfonyl)imide [BMIM][NTf 2 ], 1-butyl-3-methylimidazolium tetrafluoroborate [BMIM][BF 4 ], 1-butyl-3-methylimidazolium trifluoromethanesulfonate [BMIM][TfO], 1-butyl-3-methylimidazolium hexafluorophosphate [BMIM][PF 6 ], triethylsulfonium bis (trifluoromethylsulfonyl)imide [Et3S][NTf 2 ], 1-butyl-3-methylimidazolium tricyanomethanide [BMIM][TCM], 1-hexyl-3-methylimidazolium tetrafluoroborate [HMIM][BF 4 ] were investigated by solution calorimetry and FTIR-spectroscopy techniques. The stretching vibration region of C O group of 2-pentanone in mixture with N -alkyl substituted ionic liquid in inert solvent carbon tetrachloride was analyzed at different concentrations of components for the estimation of proton donor ability of ionic liquids. Also, the stretching vibration region of the OH-group of methanol was studied in a ternary system carbon tetrachloride (inert solvent), methanol (proton donor) and N -alkyl substituted ionic liquid for the estimation of proton acceptor ability of ionic liquids. The hydrogen bond enthalpy of methanol in ionic liquids was calculated using data of measured solution enthalpies and data extracted from the literature. The frequency shifts of the OH-group of methanol induced by intermolecular interactions within ionic liquids in a carbon tetrachloride solution were compared with the hydrogen bonding enthalpies of methanol with ionic liquids. A linear relationship between the frequency shifts of the OH-groups and hydrogen binding enthalpies of methanol in ionic liquids were found. According to measured FTIR-spectroscopy data, the N -alkyl substituted ionic liquids analyzed in this work possess weak proton donor properties, and at the same time their proton acceptor ability (basicity) is much higher and shows dependency on anion structure. [ABSTRACT FROM AUTHOR]

Using a laser-equivalent linear energy transfer (LET) approach, strong correlation is found for collected charge following heavy-ion and pulsed-laser excitation in a bulk diode device. By significantly modifying the size of the charge distribution generated by one- and two-photon absorption compared to the depth of the sensitive region, charge deposition in a large variety of device technologies is mimicked. Nearly one-to-one correlation is found with heavy-ion charge collection, independent of the laser focusing geometry or magnitude of LET. Finally, this approach is applied to the previous studies where empirical laser-ion correlations on highly scaled technologies were proposed. These correlations are reproduced through direct calculation of the laser-equivalent LET, and outstanding observations are explained despite the sensitive areas of these devices being up to 1000 times smaller than the laser-deposited charge profile. In total, these studies suggest that this quantitative methodology for laser-ion correlation is broadly applicable for a range of complex device technologies. [ABSTRACT FROM AUTHOR]

• The stability of BSA and HSA in cholinium-based ILs with biological origin anions has been study. • Biomolecular interactions between BSA/HSA and ILs was estimated. • The role of methylene group in anion of ILs was established. • Cytotoxicity of ILs on cancer and normal cell lines was analyzed. The intermolecular interactions of cholinium-based ionic liquids (ILs) with biological origin anions (amino and dicarboxylic acids) with bovine serum albumin (BSA) and human serum albumin (HSA) have been studied by spectral and computational methods. The choline malonate ([Ch][Mal]), choline succinate ([Ch][Suc]) and choline valinate ([Ch][Val]) were synthesized. The changes to the state of the BSA and HSA with ILs at different concentration were observed using circular dichroism (CD) spectroscopy. At higher concentrations the ILs lead to a partial loss of ternary structure of albumins. The effect of ILs on the thermal stability of proteins was monitored by the temperature CD spectra scans. The increase of denaturation temperature of albumins with ionic liquids was observed. The interaction of ionic liquids with serum albumins was estimated by fluorescence spectroscopy technique, while the probable binding modes were identified using molecular docking. The leading cause of the increased thermal stability of albumins was found to be the formation of aggregates of proteins with ionic liquids. Cytotoxicity of ionic liquids on cancer and normal cell lines was established. [ABSTRACT FROM AUTHOR]

• The effect of ILs on BSA was analyzed by spectral and computational methods. • The imidazolium- and cholinium-based ILs promote aggregation of BSA. • The stability of the tertiary structure of BSA is enhanced by the studied ionic liquids. • IL with octyl chain binds to BSA and does not increase its stability. The present work describes the effect of imidazolium- and cholinium-based ionic liquids (ILs) on the thermal stability, binding and aggregation of bovine serum albumin (BSA). The studied ILs include choline chloride [Ch][Cl], choline dihydrogenphosphate [Ch][DHP], choline acetate [Ch][OAc], 1-butyl-3-methylimidazolium tetrafluoroborate [BMIM][BF 4 ], 1-octyl-3-methylimidazolium tetrafluoroborate [OMIM][BF 4 ] 1-butyl-3-methylimidazolium trifluoromethanesulfonate [BMIM][TfO], 1-butyl-3-methylimidazolium acetate [BMIM][OAc], and 1-butyl-3-methylimidazolium methanesulfonate [BMIM][CH 3 SO 3 ]. The state of BSA in presence of ILs was assessed by circular dichroism (CD), temperature dependent circular dichroism, fluorescence spectroscopy, and dynamic light scattering (DLS). The thermal stability of BSA in presence of ILs increased (above 85 °C) in all studied ILs except [OMIM][BF 4 ]. Differences of binding ILs with BSA depending on alkyl chain length were estimated, the probable binding modes were identified using molecular docking. The influence of ILs on the aggregation of BSA at different temperatures was established. It was found that the ILs with short alkyl chain length (up to butyl) promote aggregation of the native form of BSA increasing its thermal stability. [ABSTRACT FROM AUTHOR]

The neurophysiological mechanisms underlying the central processing of incoming visual information is still a fundamental problem in the visual neuroscience. The response patterns of visually sensitive neurons in extrastriate area 21a of the cat cortex to the stationary and moving visual stimuli were studied in detail. The results of experiments show significant modulations of neuronal response patterns at the introduction of a moving visual stimulus, which could not be explained by the neuron receptive field (RF) stationary structure. The results of presented experiments have shown that neurons having homogenous stationary RFs structure may reveal multimodal patterns of responses to moving visual stimuli and such response profiles could be evoked from the isolated RF subfields too. Thus, with great probability, mutual interactions among simultaneously activated neighbouring neuron networks become to be of great importance in central processing of visual information, concerning the precise diversification and perception of visual images. [ABSTRACT FROM AUTHOR]

An interval t -coloring of a multigraph G is a proper edge coloring with colors 1 , … , t such that the colors of the edges incident with every vertex of G are colored by consecutive colors. A cyclic interval t -coloring of a multigraph G is a proper edge coloring with colors 1 , … , t such that the colors of the edges incident with every vertex of G are colored by consecutive colors, under the condition that color 1 is considered as consecutive to color t . Denote by w ( G ) ( w c ( G ) ) and W ( G ) ( W c ( G ) ) the minimum and maximum number of colors in a (cyclic) interval coloring of a multigraph G , respectively. We present some new sharp bounds on w ( G ) and W ( G ) for multigraphs G satisfying various conditions. In particular, we show that if G is a 2 -connected multigraph with an interval coloring, then W ( G ) ≤ 1 + | V ( G ) | 2 ( Δ ( G ) − 1 ) . We also give several results towards the general conjecture that W c ( G ) ≤ | V ( G ) | for any triangle-free graph G with a cyclic interval coloring; we establish that approximate versions of this conjecture hold for several families of graphs, and we prove that the conjecture is true for graphs with maximum degree at most 4 . [ABSTRACT FROM AUTHOR]

Spatial variations of single-event transient (SET) sensitivity in Al0.25Ga0.75N/GaN HEMTs are revealed using focused, pulsed UV laser light. SETs in regions of enhanced sensitivity have larger amplitudes and are termed “hot spots.” They are the same regions where large temperature changes are observed with thermoreflectance thermography. Both effects are attributed to the presence of material defects: SETs with enhanced amplitudes have reduced decay times due to thermally assisted detrapping; increased temperature is due to carrier scattering by the same defects. [ABSTRACT FROM PUBLISHER]

The aim of this study was to compare the efficacy of different methods of sutureless fixation of lightweight meshes made of different polymers for repair of experimental hernias. Two lateral hernia defects were modeled in male rats and covered with polyester and polypropylene prostheses. The meshes were fixed with Histacryl glue (group 1), or self-gripping meshes were used (group 2), or the meshes were implanted without fixation (group 3). On day 5 after surgery, mesh position and efficiency of fixation were evaluated. It was found that fixation is necessary for all light surgical meshes. Polyester meshes demonstrated better adhesive properties than polypropylene meshes. The most pronounced differences in the adhesive properties were found for self-gripping prosthesis, while in the groups with glue fixation, the differences were less pronounced. [ABSTRACT FROM AUTHOR]

A proper t -edge-coloring of a graph G is a mapping α : E ( G ) → { 1 , … , t } such that all colors are used, and α ( e ) ≠ α ( e ′ ) for every pair of adjacent edges e , e ′ ∈ E ( G ) . If α is a proper edge-coloring of a graph G and v ∈ V ( G ) , then the spectrum of a vertex v , denoted by S ( v , α ) , is the set of all colors appearing on edges incident to v . The deficiency of α at vertex v ∈ V ( G ) , denoted by d e f ( v , α ) , is the minimum number of integers which must be added to S ( v , α ) to form an interval, and the deficiency d e f ( G , α ) of a proper edge-coloring α of G is defined as the sum ∑ v ∈ V ( G ) d e f ( v , α ) . The deficiency of a graph G , denoted by d e f ( G ) , is defined as follows: d e f ( G ) = min α d e f ( G , α ) , where minimum is taken over all possible proper edge-colorings of G . For a graph G , the smallest and the largest values of t for which it has a proper t -edge-coloring α with deficiency d e f ( G , α ) = d e f ( G ) are denoted by w d e f ( G ) and W d e f ( G ) , respectively. In this paper, we obtain some bounds on w d e f ( G ) and W d e f ( G ) . In particular, we show that for any l ∈ N , there exists a graph G such that d e f ( G ) > 0 and W d e f ( G ) − w d e f ( G ) ≥ l . It is known that for the complete graph K 2 n + 1 , d e f ( K 2 n + 1 ) = n ( n ∈ N ). Recently, Borowiecka-Olszewska, Drgas-Burchardt and Hałuszczak posed the following conjecture on the deficiency of near-complete graphs: if n ∈ N , then d e f ( K 2 n + 1 − e ) = n − 1 . In this paper, we confirm this conjecture. [ABSTRACT FROM AUTHOR]

In this work thermochemistry of solvation of mono-, di-, tri- and tetra-substituted benzenes in 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF 4 ]) ionic liquid was studied. Enthalpies of solution at infinite dilution of 34 substituted benzenes in [BMIM][BF 4 ] were measured at 298.15 K using solution calorimetry technique. Based on the experimental and literature data enthalpies of solvation of 36 substituted benzenes in [BMIM][BF 4 ] were calculated. It was shown that enthalpies of solvation of substituted benzenes in [BMIM][BF 4 ] are independent on the mutual position of subtituents and dipole moment of molecules. Group contribution scheme for prediction of enthalpies of solvation of substituted benzenes was applied. Values of methyl- (CH 3 ), tert -butyl- ( tert -C 4 H 9 ), bromo- (Br), iodo- (I), amino- (NH 2 ), methoxy- (OCH 3 ), dimethylamino- (N(CH 3 ) 2 ), methylcarboxylate- (COOCH 3 ) group contributions to the enthalpies of solvation in [BMIM][BF 4 ] were derived and compared with molecular solvents. Solvation enthalpies of substituted benzenes in [BMIM][BF 4 ] calculated through group contribution scheme were in good agreement with experimental data. [ABSTRACT FROM AUTHOR]

Simplified analytic expressions are presented for calculating pulsed-laser induced charge generation in devices with collection volumes of any size. The expressions for charge generation by single-photon absorption for various limiting cases are applied to charge-collection measurements for a bulk Si photodiode, and single-event upsets in a 90-nm CMOS, silicon on insulator (SOI), static random-access memory (SRAM). Strong quantitative agreement between the simplified expressions, the full numerical calculations, and the experimental data serves to validate the analytical expressions. Furthermore, despite the complexity of determining charge deposited via two-photon absorption, the analytic expressions exhibit excellent agreement with full charge-generation simulations utilizing nonlinear-optical beam propagation software. These expressions therefore, represent a convenient and accurate method for estimating pulsed-laser induced charge generation in specified volumes, and are particularly relevant for two-photon absorption, which previously has required the use of complex numerical approaches. [ABSTRACT FROM AUTHOR]

We investigate the behavior of the transmission and reflection bands for a plane electromagnetic wave falling obliquely on an ideal layered structure. The width of allowed bands as function of the structure parameters and the wave incident angle is considered. It is shown, that in general case the bandwidth is a non-monotonous function of the problem parameters. The conditions defining the contact of the transmission bands for the both types of wave polarizations are derived. It is proved that irrespective of the wave polarization, the transmission coefficient equals to unit at the contact points. It is also shown that in the case of Brewster angle the contact of the allowed ρ bands is also take place. [ABSTRACT FROM AUTHOR]

An emerging trend with semiconductor quantum dots (QDs) is their use as scaffolds to assemble multiple energy transfer pathways. Examples to date have combined various competitive and sequential Förster resonance energy transfer (FRET) pathways between QDs and fluorescent dyes, luminescent lanthanide complexes, and bioluminescent proteins. Here, we show that the photoluminescence (PL) of QD bioconjugates can also be modulated by a combination of FRET and charge transfer (CT), and characterize the concurrent effects of these mechanistically different pathways using PL measurements at both the ensemble and the single particle level. Peptides were distally labeled with either a fluorescent dye that quenched QD PL through FRET or a ruthenium(II) phenanthroline complex that quenched QD PL through electron transfer. The labeled peptides were assembled around a central CdSe/ZnS QD at different ratios, tuning the relative rates of FRET and CT, which were competitive quenching pathways. The concurrent effects of FRET and CT were predictable from a rate analysis that was calibrated to the isolated effects of each of these pathways. Notably, the dye/QD PL intensity ratio reflected changes in the relative rate of FRET but was approximately independent of CT. In turn, the sum of the QD and dye PL intensities, when adjusted for quantum yields, reflected changes in the relative rate of CT quenching, approximately independent of FRET. The capacity for multiplexed sensing of protease activity was demonstrated using these two orthogonal detection channels. Combined CT-FRET configurations with QDs are thus promising for applications in bioanalysis, sensing, and imaging, and may prove useful in other photonic applications. [ABSTRACT FROM AUTHOR]

In this paper a new public key encryption system based on permutation polynomials is developed. The permutation polynomial P ( x ) is declared to be a public polynomial for encryption. A public key encryption of given m ( x ) is the evaluation of polynomial P ( x ) at point m ( x ) where the result of evaluation is calculated via so called White box reduction, which does not reveal the underlying secret polynomial g ( x ) . It is shown that for the new system to achieve a comparable security with conventional public key systems based on either Discrete logarithm or Integer factorization problems, substantially less processing length n is required resulting in a significant acceleration of public key operations. [ABSTRACT FROM AUTHOR]

A focused, pulsed x-ray beam was used to compare SET characteristics in pristine and proton-irradiated Al0.3Ga0.7N/GaN HEMTs. Measured SET amplitudes and trailing-edge decay times were analyzed as was the collected charge, obtained by integrating the SET pulses over time. SETs generated in proton-irradiated HEMTs differed significantly from those in pristine HEMTs with regard to the decay times and collected charge. The decay times have previously been shown to be attributed to charge trapping by defect states that are caused either by imperfect material growth conditions or by proton-induced displacement damage. The longer decay times observed for proton-irradiated HEMTs are attributed to the presence of additional deep traps created when protons lose energy as they collide with the nuclei of constituent atoms. Comparison of electrical parameters measured before and immediately following exposure to the focused x-ray beam showed little change, confirming the absence of significant charge buildup in passivation layers by the x-rays themselves. A major advantage of the pulsed x-ray technique is that the region under the metal gate can be probed for single-event transients from the top side, an approach incompatible with pulsed-laser SEE testing that involves the use of visible light. [ABSTRACT FROM PUBLISHER]

In this work thermochemistry of solution and solvation of mono- and di-substituted chloro- and nitro-benzenes in 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4]), 1-butyl-3-methylimidazolium trifluoromethanesulfonate ([BMIM][TfO]) and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([BMIM][NTf2]) ionic liquids was studied. Enthalpies of solution at infinite dilution of benzene, chlorobenzene, nitrobenzene, 1,2-, 1,3-, 1,4-dichlorobenzenes, 1,2-, 1,3-, 1,4-dinitrobenzenes, 1-chloro-2-nitrobenzene, 1-chloro-3-nitrobenzene, and 1-chloro-4-nitrobenzene in three ionic liquids were measured at 298.15 K. On the basis of experimental data enthalpies of solvation of substituted benzenes in ionic solvents were calculated. Values of Cl and NO 2 group contributions to the enthalpies of solvation were derived and compared with molecular solvents. Enthalpies of solvation of each series of dichlorobenzenes, chloronitrobenzenes and dinitrobenzenes in studied ionic liquids are equal and do not depend on the mutual position of substituents. This fact shows that dipole moment does not affect the enthalpy of solvation of organic solutes in ionic liquids. Enthalpies of solvation of disubstituted benzenes in ionic liquids calculated through group contribution approach were in good agreement with experimental data. [ABSTRACT FROM AUTHOR]

In this work the thermodynamics of intermolecular interactions for imidazolium based ionic liquids in solutions of proton donor solvent chloroform and proton acceptor solvent tetrahydrofuran was studied using solution calorimetry technique. Enthalpies of solution of 1-ethyl- and 1-butyl-3-methylimidazolium based ionic liquids with tetrafluoroborate, methylsulfate, ethylsulfate, butylsulfate, dicyanoamide, trifluoromethanesulfonate, thiocyanate anions were measured in two solvents over concentration range 0.18-3.60 mmol kg −1 at 298.15 K. Enthalpies of transfer from tetrahydrofuran to chloroform derived from experimental data were exothermic for all studied ionic liquids. Proton acceptor scale of ionic liquids as solutes was proposed on the basis of thermochemical data. Enthalpy of hydrogen bonding of ionic liquids with proton donor solvent chloroform increases in the range of anions [BF 4 ] − < [SCN] − < [TfO] − < [N(CN) 2 ] − < [AlkSO 4 ] − . At the same time these values remain constant for ILs with different length of alkyl group in cations and anions. Thermochemical proton acceptor scale of ILs in solution correlates well with COSMO-RS hydrogen-bonding energies in equimolar cation–anion pairs of ILs. [ABSTRACT FROM AUTHOR]

An edge-coloring of a graph G with colors 1 , 2 , … , t is an interval t -coloring if all colors are used, and the colors of edges incident to each vertex of G are distinct and form an interval of integers. A graph G is interval colorable if it has an interval t -coloring for some positive integer t . For an interval colorable graph G , W ( G ) denotes the greatest value of t for which G has an interval t -coloring. It is known that the complete graph is interval colorable if and only if the number of its vertices is even. However, the exact value of W ( K 2 n ) is known only for n ≤ 4 . The second author showed that if n = p 2 q , where p is odd and q is nonnegative, then W ( K 2 n ) ≥ 4 n − 2 − p − q . Later, he conjectured that if n ∈ N , then W ( K 2 n ) = 4 n − 2 − ⌊ log 2 n ⌋ − ‖ n 2 ‖ , where ‖ n 2 ‖ is the number of 1’s in the binary representation of n . In this paper we introduce a new technique to construct interval colorings of complete graphs based on their 1-factorizations, which is used to disprove the conjecture, improve lower and upper bounds on W ( K 2 n ) and determine its exact values for n ≤ 12 . [ABSTRACT FROM AUTHOR]

The propagation of Analog Single Event Transients (ASETs) to multiple outputs of Bipolar Junction Transistor (BJTs) Integrated Circuits (ICs) is reported for the first time. The results demonstrate that ASETs can appear at several outputs of a BJT amplifier or comparator as a result of a single ion or single laser pulse strike at a single physical location on the chip of a large-scale integrated BJT analog circuit. This is independent of interconnect cross-talk or charge-sharing effects. Laser experiments, together with SPICE simulations and analysis of the ASET’s propagation in the s-domain are used to explain how multiple-output transients (MOTs) are generated and propagate in the device. This study demonstrates that both the charge collection associated with an ASET and the ASET’s shape, commonly used to characterize the propagation of SETs in devices and systems, are unable to explain quantitatively how MOTs propagate through an integrated analog circuit. The analysis methodology adopted here involves combining the Fourier transform of the propagating signal and the current-source transfer function in the s-domain. This approach reveals the mechanisms involved in the transient signal propagation from its point of generation to one or more outputs without the signal following a continuous interconnect path. [ABSTRACT FROM PUBLISHER]

Carrier injection by single-photon absorption using ultraviolet optical pulses is used to investigate single-event transients in pristine and proton-irradiated AlGaN/GaN HEMTs. High-precision spatial mapping of defects and traps in AlGaN/GaN HEMT devices identify regions of enhanced SET signals, or “hot spots” that are ascribed to the presence of lattice defects that modify the electric field in the structure. The resulting transient shape and amplitude depend strongly on the specific location of the injected carriers, and vary with changes in gate and drain bias. Proton irradiation significantly alters transient signal shapes, increases the integrated collected charge, and increases density of defects and traps. [ABSTRACT FROM PUBLISHER]

• The comparative analysis the solvation enthalpies of organic solutes in ionic liquids and molecular solvents was carried out. • The effects of the solute structure on the solvation enthalpy in ionic liquids are close to the molecular solvents. • The relative place of ionic liquids among other solvents in terms of intermolecular interactions was determined. The present review is devoted to the critical analysis of literature and own data on the solution and solvation enthalpies of nonelectrolytes in ionic liquids. The analysis is based on the concept of the relationship between the structure of the solute molecules and the intermolecular solute–solvent interactions. It was shown that the contribution of the solvophobic effect to the solvation enthalpy of nonelectrolytes in ionic liquid is insignificant. Despite the ion–dipole solvent–solvent interactions in the ionic liquids, the contribution of polar solute–solvent interactions to the solvation enthalpy of is also negligible. Based on data on the solvation enthalpies of aromatic and heteroaromatic derivatives in ionic liquids, an additive scheme for calculating the corresponding solvation enthalpies is proposed. Previously developed approaches to dividing the solvation enthalpy into the contributions from the nonspecific solvation and specific interactions have been applied to ionic liquids. The enthalpies of the solute–solvent hydrogen bonding were determined. In each of the cases considered above, a comparison with the data on the solvation enthalpies of the same non-electrolytes in benzene and N,N -dimethylformamide was made in order to determine the relation of ionic liquids to common solvents. It was shown that the structure effects of dissolved nonelectrolyte molecules on their solvation enthalpy in ionic liquids do not differ significantly from the ordinary solvents. [ABSTRACT FROM AUTHOR]

An analytical formula is obtained from first principles describing the temperature dependence of the elastic modulus of borides, carbides, oxides, nitrides, composites, metals (both simple and transitional), as well as high-entropy alloys (HEAs). [ABSTRACT FROM AUTHOR]