212 research outputs found
ІНДИВІДУАЛЬНО-ПСИХОЛОГІЧНІ ОСОБЛИВОСТІ ПЕРЕЖИВАННЯ САМОТНОСТІ СЕРЕД МОЛОДІ
The paper deals with theoretical study of phenomenon of loneliness. The psychological features of teenagers’ loneliness experiencing are analyzed. The results of empiric research of interrelation feeling of loneliness with individual-psychological characteristics are presented.Исследованы теоретические аспекты феномена одиночества. Проанализированы особенности переживания одиночества в подростковом возрасте. Представлено эмпирическое исследование взаимосвязи чувства одиночества с индивидуально-психологическими характеристиками подростков.Досліджено теоретичні аспекти феномена самотності. Проаналізовано особливості переживання самотності у підлітковому віці. Представлено емпіричне дослідження взаємозв’язку відчуття самотності з індивідуально-психологічними характеристиками підлітків
Observation of superluminal geometrical resonances in Bi2Sr2CaCu2O8+x intrinsic Josephson junctions
We study Fiske steps in small Bi2Sr2CaCu2O8+x mesa structures, containing
only few stacked intrinsic Josephson junctions. Careful alignment of magnetic
field prevents penetration of Abrikosov vortices and facilitates observation of
a large variety of high quality geometrical resonances, including superluminal
with velocities larger than the slowest velocity of electromagnetic waves. A
small number of junctions limits the number of resonant modes and allows
accurate identification of modes and velocities. It is shown that superluminal
geometrical resonances can be excited by subluminal fluxon motion and that
flux-flow itself becomes superluminal at high magnetic fields. We argue that
observation of high-quality superluminal geometrical resonances is crucial for
realization of the coherent flux-flow oscillator in the THz frequency range
Fiske Steps and Abrikosov Vortices in Josephson Tunnel Junctions
We present a theoretical and experimental study of the Fiske resonances in
the current-voltage characteristics of "small" Josephson junctions with
randomly distributed misaligned Abrikosov vortices. We obtained that in the
presence of Abrikosov vortices the resonant interaction of electromagnetic
waves, excited inside a junction, with the ac Josephson current manifests
itself by Fiske steps in a current-voltage characteristics even in the absence
of external magnetic field. We found that the voltage positions of the Fiske
steps are determined by a junction size, but the Fiske step magnitudes depend
both on the density of trapped Abrikosov vortices and on their misalignment
parameter. We measured the magnetic field dependence of both the amplitude of
the first Fiske step and the Josephson critical current of low-dissipative
small based Josephson tunnel junctions with artificially introduced
Abrikosov vortices. A strong decay of the Josephson critical current and a weak
non-monotonic decrease of the first Fiske step amplitude on the Abrikosov
vortex density were observed. The experimentally observed dependencies are well
described by the developed theory.Comment: 21 pages, 7 figures, submitted to Physical Review
Pb-207 chemical shielding in lead molybdate and lead chloride: The effects of temperature and lattice expansion
The analysis of heavy-metal solids with NMR spectroscopy provides a means of investigating the electronic environment through the dependence of the chemical shift on structure. We have investigated the relation of the 207Pb NMR isotropic chemical shift, span, and skew of a series of solid Pb(II) compounds to lattice parameters. Complementary relativistic spin−orbit density functional calculations on clusters such as PbI64- that model the local environment in the dihalides show a dependence of NMR properties on the local structure in good agreement with experimental results
Quantum superposition of three macroscopic states and superconducting qutrit detector
Superconducting quantum coherent circuits have opened up a novel area of
fundamental low-temperature science since they could potentially be the element
base for future quantum computers. Here we report a quasi-three-level coherent
system, the so-called superconducting qutrit, which has some advantages over a
two-level information cell (qubit), and is based on the qutrit readout circuit
intended to measure individually the states of each qubit in a quantum
computer. The designed and implemented radio-frequency superconducting qutrit
detector (rf SQUTRID) with atomic-size ScS-type contact utilizes the
coherent-state superposition in the three-well potential with energy splitting
Delta E_01/k_B=1.5 K at the 30th quantized energy level with good isolation
from the electromagnetic environment. The reason why large values of Delta E_01
(and thus using atomic-size Nb-Nb contact) are required is to ensure an
adiabatic limit for the quantum dynamics of magnetic flux in the rf SQUTRID.Comment: 9 pages, 5 figures, in v.3: text extended, inset in figure 1 (the
device design) adde
Effects of different fertilizer systems and hydrothermal factors on microbial activity in the chernozem in Ukraine
Groups of microorganisms in soils perform the role of global biogeochemical membrane which provides metabolism of substances and energy between the pedosphere, lithosphere, hydrosphere and living organisms. Сlimate change has resulted in a complex combination of unpredictable changeability of the environment, which is a serious test for the stability and productivity for the natural and anthropogenically transformed ecosystems. Changeability of the hydrothermal factors causes serious changes in the structure and metabolic activity of soil microorganisms, the quality and properties of soil. We studied the impact of hydrothermal factors on the content of carbon, microbial biomass and organic substance in deep chernozem of a natural ecosystem (fallow) and an agroecosystem under different systems of fertilization of winter wheat. A close relationship (r = 0.69–0.79) was determined between the content of microbial biomass in soil and hydrothermal factors (air temperature and moisture). Excessive drought and high parameters of air temperature led to decrease in the content of microbial biomass by 1.5–2.8 times compared to the years with optimum parameters of hydrothermal regime (HTC = 1.0). Leveling out the impact of high temperatures on the productivity of the soil microbiota occurs at a sufficient amount of moisture, and also available nutrients. Drought (HTC = 0.4) and excessive moisture (HTC = 2.0) following heightened air temperatures reduce the release of СО2 from soil. Fallow soil usually has a high content of microbial carbon in the organic compounds of soil (Сmic/Сorg was 2%). In the agroecosystem, there was recorded a decrease by 26–32% of the Сmic specific share in the content of the organic compound of the soil compared to the natural analogue. With organic and organic-mineral systems of fertilization, an increase in Сmic/Сorg parameter occurs and the soil parameters become close to the soil of a natural ecosystem. The calculated ecological coefficients of the orientation of microbial processes in soil indicate a possibility of a balanced functioning of the microbial group and introducing organic and organic-mineral fertilizers, creating optimum conditions for the productivity of winter wheat
Features of exogenous development of Trichuris globulosa (Nematoda, Trichuridae)
Parasitic nematodes of the genus Trichuris Röderer, 1761 are hematophagous helminths, capable of parasitizing many different hosts including humans. The domestic and wild ruminants are hosts of several Trichuris species, with Trichuris globulosa (Linstow, 1901) one of the most prevalent parasites found in cattle. The exogenous stages of the helminth’s life cycle develop in the outer environment, and their activity and survival depend on the abiotic factors. Thus the aim of the work was to determine the influence of temperature on the rate and success of development of infectious eggs of T. globulosa in laboratory culture considering their morphological and metric changes. The results of experimental studies showed that the embryogenesis of T. globulosa eggs, cultured in laboratory conditions and obtained from gonads of female nematodes, occurs in six stages regardless of the temperature regime. At the same time, the rate of transition from one stage to another, the term for the formation of infectious eggs and their viability directly depends on the temperature of the external environment. At the optimal temperature for the development of T. globulosa eggs, 25 °C, 76.3% of eggs reached the mobile larva stage. A decrease in temperature to 20 °C and an increase to 30° C led to an increase in the egg mortality of up to 26% and 32%, respectively, and the viability of eggs decreased. Under such temperature conditions, 74% and 68% of eggs of Trichuris reached the mobile larva stage. With an increase in the culture temperature, the time of embryogenesis decreased and amounted to 56 days at 20 °C, 48 days at 25 °C, and 32 days at 30 °C. Depending on the temperature regime, the zygote stage lasted from the release of eggs from the gonads of female nematodes to 12 days, the stage of blastomere formation from 4 to 12 days, the stage of the bean-shaped embryo from 8 to 24 days, the stage of the tadpole embryo from 16 to 36 days, the stage of larval formation lasted from 16 to 48 days, the stage of mobile larva from days 20 to 56. The formation of the infectious T. globulosa egg from a non-infectious one is shown in an experiment to include the metric changes confirmed by metric indicators. Mature eggs with a mobile larva are shorter and wider, with shorter and narrower plugs and a thinner shell than eggs at the zygote stage. The obtained research results on the influence of temperature on the exogenous development of Trichuris globulosa will make it possible to predict the epizootic situation of trichurosis in animal husbandry, as well as take timely measures to arrest the embryonic stages of nematode development in the external environment
Laser Scanning Microscopy of HTS Films and Devices
The work describes the capabilities of Laser Scanning Microscopy (LSM) as a
spatially resolved method of testing high_Tc materials and devices. The earlier
results obtained by the authors are briefly reviewed. Some novel applications
of the LSM are illustrated, including imaging the HTS responses in rf mode,
probing the superconducting properties of HTS single crystals, development of
twobeam laser scanning microscopy. The existence of the phase slip lines
mechanism of resistivity in HTS materials is proven by LSM imaging.Comment: 17 pages, 21 figures, Submitted to Fizika Nizkikh Temperatur (Low
Temperature Physics
Fractional ac Josephson effect in unconventional superconductors
For certain orientations of Josephson junctions between two p_x-wave or two
d-wave superconductors, the subgap Andreev bound states produce a 4pi-periodic
relation between the Josephson current I and the phase difference phi: I ~
sin(phi/2). Consequently, the ac Josephson current has the fractional frequency
eV/h, where V is the dc voltage. In the tunneling limit, the Josephson current
is proportional to the first power (not square) of the electron tunneling
amplitude. Thus, the Josephson current between unconventional superconductors
is carried by single electrons, rather than by Cooper pairs. The fractional ac
Josephson effect can be observed experimentally by measuring frequency spectrum
of microwave radiation from the junction.Comment: 8 pages, 3 figures, RevTEX 4; v2. - minor typos corrected in proof
APPLICATION OF THE INTERACTIVE METHODS IN STUDENT-CENTERED HIGH SCHOOL EDUCATION
The article deals with the problem of the need to improve the level of methodological preparation of professional activities of teachers in higher education. Interactive teaching methods, which have been developing intensively lately, more actively contribute to this. Due to the self-sufficient activity and group interaction inherent in their essence, they can be useful and promising for both teachers and students. The author reveals the popular forms and methods of interactive learning in the article. Also highlights the main advantages and disadvantages of this technology. A brief overview of group work using interactive teaching methods in higher education.Keywords: university, technology, interactive learning, teacher, pedagogical skills, student. В статье рассмотрена проблема необходимости повышения уровня методической подготовки профессиональной деятельности преподавателя в высшей школе. Лучше способствуют этому интерактивные методы обучения, которые интенсивно разрабатываются в последнее время. Благодаря заложенным в их суть самостоятельной деятельности и групповом взаимодействии, они могут быть полезными и перспективными как для преподавателя, так и для студентов. Авторы раскрывают в статье популярные формы и методы интерактивного обучения. Также подчеркиваются основные преимущества и недостатки данной технологии. Кратко приведен обзор групповой работы с использованием интерактивных методов обучения в высшей школе.Ключевые слова: высшая школа, технология, интерактивное обучение, преподаватель, педагогическое мастерство, студент. У статті розглянуто проблему необхідності підвищення рівня методичної підготовки професійної діяльності викладача у вищій школі. Якнайкраше сприяють цьому інтерактивні методи навчання, що активно розробляються останнім часом. Завдяки закладеним в їх суть самостійній діяльності та груповій взаємодії, вони можуть бути корисними та перспективними як для викладача, так і для студентів. Автори розкривають у статті найпопулярніші форми і методи інтерактивного навчання. Також підкреслюються основні переваги та недоліки даної технології. Стисло наведено огляд групової роботи з використанням інтерактивних методів навчання у вищій школі.Ключові слова: вища школа, технологія, інтерактивне навчання, викладач, педагогічна майстерність, студент
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