Zero-valent intercalation of atomic metals into the van der Waals gap of layered materials can be used to tune their electronic, optical, thermal, and mechanical properties. Here, we report the impact of intercalating ∼3 atm percent of zero-valent copper into germanium sulfide (GeS). Advanced many-body calculations predict that copper introduces quasi-localized intermediate band states, and time-resolved THz spectroscopy studies demonstrate that those states have prominent effects on the photoconductivity of GeS.
View Article and Find Full Text PDFThe review considers modern data on the mechanisms of activation and redox regulation of the NLRP3 inflammasome and gasdermins, as well as the role of selenium in these processes. Activation of the inflammasome and pyroptosis represent an evolutionarily conserved mechanism of the defense against pathogens, described for various types of cells and tissues (macrophages and monocytes, microglial cells and astrocytes, podocytes and parenchymal cells of the kidneys, periodontal tissues, osteoclasts and osteoblasts, as well as cells of the digestive and urogenital systems, etc.).
View Article and Find Full Text PDF2D MXenes have diverse and chemically tunable optical properties that arise from an interplay between free carriers, interband transitions, and plasmon resonances. The nature of photoexcitations and their dynamics in three different members of the MXene family, Ti C , Mo Ti C , and Nb C, are investigated using two complementary pump-probe techniques, transient optical absorption, and time-resolved terahertz (THz) spectroscopy. Measurements reveal pronounced plasmonic effects in the visible and near-IR in all three.
View Article and Find Full Text PDFMeaning in life (MIL) has been proposed to improve coping and resilience. Yet MIL's association with coping has primarily been investigated in the context of extreme stressors and trauma, often using varied measures of MIL. Is MIL associated with varied coping strategies, coping self-efficacy, and distress in relation to commonly experienced, everyday challenges? Using diverse methodological designs, five studies (total = 1,646) investigated the association between MIL and coping strategies/appraisals pertaining to varied challenging, stressful events.
View Article and Find Full Text PDFMicroorganisms exhibit seasonal succession governed by physicochemical factors and interspecies interactions, yet drivers of this process in different environments remain to be determined. We used high-throughput sequencing of 16S rRNA and 18S rRNA genes to study seasonal dynamics of bacterial and microeukaryotic communities at pelagic site of Lake Baikal from spring (under-ice, mixing) to autumn (direct stratification). The microbial community was subdivided into distinctive coherent clusters of operational taxonomic units (OTUs).
View Article and Find Full Text PDFHigh electrical conductivity and strong absorption of electromagnetic radiation in the terahertz (THz) frequency range by metallic 2D MXene TiCT make it a promising material for electromagnetic interference shielding, THz detectors, and transparent conducting electrodes. Here, we demonstrate that ultrafast optical pulses with wavelengths straddling the visible range (400 and 800 nm) induce transient broad-band THz transparency in the MXene that persists for nanoseconds. We demonstrate that optically induced transient THz transparency is independent of temperature from 95 to 290 K.
View Article and Find Full Text PDFTheory predicts that a large spontaneous electric polarization and concomitant inversion symmetry breaking in GeSe monolayers result in a strong shift current in response to their excitation in the visible range. Shift current is a coherent displacement of electron density on the order of a lattice constant upon above-bandgap photoexcitation. A second-order nonlinear effect, it is forbidden by the inversion symmetry in the bulk GeSe crystals.
View Article and Find Full Text PDFThe article describes the results of a comparative prospective study of the results of correcting age-related changes in the skin of the face and neck in 72 patients using native platelet auto plasma and a new method for obtaining its thermally processed modifications based on the denaturation of protein plasma fractions when heated in a thermostat to different temperatures. (Patent No. 2629527/August 29, 2017.
View Article and Find Full Text PDFEvery year about 800,000 cases of intestinal infections end in lethal outcome due to dehydration. The different types of dehydration acquire differential approach to correction. Everywhere there is no application of routine detection of osmolarity of blood plasma under exicosis in children in view of absence of possibility of instrumental measurement.
View Article and Find Full Text PDFThe article tells about one of the actual problem of the provision of medical and social care for elderly and old aged people, through the organization of nursing care beds in the Voronezh region. Since the beginning of 2014 there were organized 320 such beds in 27 medical organizations of the region. Regular surveys of patients and their relatives, as well as personnel involved in the care service, made it possible to make the necessary adjustments and the further expansion of services in other hospitals.
View Article and Find Full Text PDFWe have generated coherent pulses of terahertz radiation from macroscopic arrays of aligned single-wall carbon nanotubes (SWCNTs) excited by femtosecond optical pulses without externally applied bias. The generated terahertz radiation is polarized along the SWCNT alignment direction. We propose that top-bottom asymmetry in the SWCNT arrays produces a built-in electric field in semiconducting SWCNTs, which enables generation of polarized terahertz radiation by a transient photocurrent surge directed along the nanotube axis.
View Article and Find Full Text PDFThe objective of this study was to improve the immediate and long-term results of combined treatment of patients with locally advanced rectal cancer. The study included 128 patients with morphologically confirmed diagnosis and clinical stage cT3/T4 and N-/N+, treated from 1998 to 2009. The comparison group had 64 patients, combined treatment included prolonged preoperative radiotherapy 4 Gy and 40 Gy, surgery was performed after 4 weeks.
View Article and Find Full Text PDFThe syntheses of colloidal silicon nanocrystals (Si-NCs) with dimensions in the 3-4 nm size regime as well as effective methodologies for their functionalization with alkyl, amine, phosphine, and acetal functional groups are reported. Through rational variation in the surface moieties we demonstrate that the photoluminescence of Si-NCs can be effectively tuned across the entire visible spectral region without changing particle size. The surface-state dependent emission exhibited short-lived excited-states and higher relative photoluminescence quantum yields compared to Si-NCs of equivalent size exhibiting emission originating from the band gap transition.
View Article and Find Full Text PDFTerahertz (THz) radiation lies between the infrared and microwave regions of the electromagnetic spectrum and is non-ionizing. We show that exposure of artificial human skin tissue to intense, picosecond-duration THz pulses affects expression levels of numerous genes associated with non-melanoma skin cancers, psoriasis and atopic dermatitis. Genes affected by intense THz pulses include nearly half of the epidermal differentiation complex (EDC) members.
View Article and Find Full Text PDFSimulation results obtained with an individual-based model describing spatial movement and interactions of predators and prey within a closed rectangular habitat are represented. Movement of each individual animal is determined by local conditions only, thus any collective behaviour emerges due to self-organization. It is shown that the pursuit of the prey by predators leads to the emergence of predator interference manifesting itself at the population level as the dependence of the trophic function on predator abundance (predator-dependence).
View Article and Find Full Text PDFRecent emergence and growing use of terahertz (THz) radiation for medical imaging and public security screening raise questions on reasonable levels of exposure and health consequences of this form of electromagnetic radiation. In particular, picosecond-duration THz pulses have shown promise for novel diagnostic imaging techniques. However, the effects of THz pulses on human cells and tissues thus far remain largely unknown.
View Article and Find Full Text PDFOn the basis of natural exopolysaccharide xanthan and exopolyacrylamide the sticky-gene composition has been developed. Addition of that composition to the culture medium provided a 26.3 times higher viability of Bradyrhizobium japonicum UCM B-6035 cells during its storage.
View Article and Find Full Text PDFJ Nanosci Nanotechnol
March 2011
The process of forming three-component nanocrystalline fibers and powders of zirconia, yttria and alumina is studied depending on the component ratio and heat treatment temperature. It has been found that in the investigated system at 500-600 degrees C a nanocrystalline triple solid solution is formed, which exists up to 1200 degrees C. Beyond the above temperature, the triple solid solution decomposes into individual components.
View Article and Find Full Text PDFThree predator-dependent trophic functions have been fitted to experimental data on individual ration of two phytophagous rotifers (Brachionus calyciflorus and Philodina acuticornis) in laboratory monocultures of microalgae (Chlorella vulgaris Beyer, Scenedesmus quadricauda Brev. and Synechocistis sp.).
View Article and Find Full Text PDFNonlinear transient absorption bleaching of intense few-cycle terahertz (THz) pulses is observed in photoexcited GaAs using opticalpump--THz-probe techniques. A simple model of the electron transport dynamics shows that the observed nonlinear response is due to THz-electric- field-induced intervalley scattering over sub-picosecond time scales as well as an increase in the intravalley scattering rate attributed to carrier heating. Furthermore, the nonlinear nature of the THz pulse transmission at high peak fields leads to a measured terahertz conductivity in the photoexcited GaAs that deviates significantly from the Drude behavior observed at low THz fields, emphasizing the need to explore nonlinear THz pulse interactions with materials in the time domain.
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