Spin Seebeck effect in Y-type hexagonal ferrite thin films

Spin Seebeck effect (SSE) has been investigated in thin films of two Y-hexagonal ferrites Ba$_2$Zn$_{2}$Fe$_{12}$O$_{22}$ (Zn2Y) and Ba$_2$Co$_{2}$Fe$_{12}$O$_{22}$ (Co2Y) deposited by a spin-coating method on SrTiO$_3$(111) substrate. The selected hexagonal ferrites are both ferrimagnetic with similar magnetic moments at room temperature and both exhibit easy magnetization plane normal to $c$-axis. Despite that, SSE signal was only observed for Zn2Y, whereas no significant SSE signal was detected for Co2Y. We tentatively explain this different behavior by a presence of two different magnetic ions in Co2Y, whose random distribution over octahedral sites interferes the long range ordering and enhances the Gilbert damping constant. The temperature dependence of SSE for Zn2Y was measured and analyzed with regard to the heat flux and temperature gradient relevant to the SSE signal.Comment: 7 pages, 9 figure

Hydrogen diffusion through Ru thin films

In this paper, an experimental measurement of the diffusion constant of hydrogen in ruthenium is presented. By using a hydrogen indicative Y layer, placed under the Ru layer, the hydrogen flux through Ru was obtained by measuring the optical changes in the Y layer. We use optical transmission measurements to obtain the hydrogenation rate of Y in a temperature range from room temperature to 100 °C. We show that the measured hydrogenation rate is limited mainly by the hydrogen diffusion in Ru. These measurements were used to estimate the diffusion coefficient, D, and activation energy of hydrogen diffusion in Ru thin films to be D = 5.9 × 10−14 m2/s ∙ exp (-0.33 eV/kBτ), with kB the Boltzmann constant and τ the temperature.</p

Abundance of Lygus spp. (Heteroptera:Miridae) in canola adjacent to forage and seed alfalfa

Our objectives were to document the abundance of lygus bugs (Miridae) in canola after the cutting of adjacent alfalfa hay fields and to document their seasonal activity in canola plots grown in close proximity to alfalfa seed. Cutting alfalfa did not increase abundance of lygus bugs in nearby canola in sites near Barrhead, Alberta (1998-1999), in the Peace River area of British Columbia (2000) or near Carman, Manitoba (2001). In Saskatoon, from 1993-1995, lygus bug numbers remained at low levels in seed alfalfa and canola and there was no indication that the pest species (L. lineolaris) in canola moved in significant numbers from the adjacent alfalfa seed field. We conclude that alfalfa forage harvesting generally does not result in massive movement of lygus bugs to nearby canola

BEARING CAPACITY OF HINGELESS CIRCULAR ARCHES MADE OF CONCRETE AND FIBER CONCRETE UNDER HYDROSTATIC PRESSURE

The authors presented a numerical and experimental study of the bearing capacity of circular concrete and fiber concrete arches The authors made a stand to determine the bearing capacity of arches models under hydrostatic pressure. The hingeless arches were made of C16/20 concrete; one arch was made of unreinforced concrete, and the second arch had 1% steel anchor fiber added to the mix. ANSYS software was used for computer modeling and numerical analysis by the finite element method. When testing the concrete arch, the breaking load was 710 kN, and when testing the fiber concrete arch, it was 810 kN, that is, the bearing capacity of the fiber concrete arch determined experimentally was 1.13 times higher. The results of experimental and numerical investigations agree well with each other and with the results of theoretical calculations. Comparison of normal stresses in the experiment determined at strain gauge points with their theoretical values gives a maximum discrepancy of 9.6 % for the concrete arch and 9.2 % for the fiber concrete one. It is recommended to increase the load-bearing capacity of the structure by means of a more uniform dispersed reinforcement of the arch

Radiation chemistry provides nanoscopic insights into the role of intermediate phases in CeO₂ mesocrystal formation

The role of intermediate phases in CeO2 mesocrystal formation from aqueous Ce(III) solutions subjected to gamma-radiation was studied. Radiolytically formed hydroxyl radicals convert soluble Ce(III) into less soluble Ce(IV). Transmission electron microscopy (TEM) and X-ray diffraction studies of samples from different stages of the process allowed the identification of several stages in CeO2 mesocrystal evolution following the oxidation to Ce(IV): (1) formation of hydrated Ce(IV)-hydroxides, serving as intermediates in the liquid-to-solid phase transformation; (2) CeO2 primary particle growth inside the intermediate phase; (3) alignment of the primary particles into "pre-mesocrystals" and subsequently to mesocrystals, guided by confinement of the amorphous intermediate phase and accompanied by the formation of "mineral bridges". Further alignment of the obtained mesocrystals into supracrystals occurs upon slow drying, making it possible to form complex hierarchical architectures

Studies of inactivation mechanism of non-enveloped icosahedral virus by a visible ultrashort pulsed laser

BACKGROUND: Low-power ultrashort pulsed (USP) lasers operating at wavelengths of 425 nm and near infrared region have been shown to effectively inactivate viruses such as human immunodeficiency virus (HIV), M13 bacteriophage, and murine cytomegalovirus (MCMV). It was shown previously that non-enveloped, helical viruses such as M13 bacteriophage, were inactivated by a USP laser through an impulsive stimulated Raman scattering (ISRS) process. Recently, enveloped virus like MCMV has been shown to be inactivated by a USP laser via protein aggregation induced by an ISRS process. However, the inactivation mechanism for a clinically important class of viruses – non-enveloped, icosahedral viruses remains unknown. RESULTS AND DISCUSSIONS: We have ruled out the following four possible inactivation mechanisms for non-enveloped, icosahedral viruses, namely, (1) inactivation due to ultraviolet C (UVC) photons produced by non-linear optical process of the intense, fundamental laser beam at 425 nm; (2) inactivation caused by thermal heating generated by the direct laser absorption/heating of the virion; (3) inactivation resulting from a one-photon absorption process via chromophores such as porphyrin molecules, or indicator dyes, potentially producing reactive oxygen or other species; (4) inactivation by the USP lasers in which the extremely intense laser pulse produces shock wave-like vibrations upon impact with the viral particle. We present data which support that the inactivation mechanism for non-enveloped, icosahedral viruses is the impulsive stimulated Raman scattering process. Real-time PCR experiments show that, within the amplicon size of 273 bp tested, there is no damage on the genome of MNV-1 caused by the USP laser irradiation. CONCLUSION: We conclude that our model non-enveloped virus, MNV-1, is inactivated by the ISRS process. These studies provide fundamental knowledge on photon-virus interactions on femtosecond time scales. From the analysis of the transmission electron microscope (TEM) images of viral particles before and after USP laser irradiation, the locations of weak structural links on the capsid of MNV-1 were revealed. This important information will greatly aid our understanding of the structure of non-enveloped, icosahedral viruses. We envision that this non-invasive, efficient viral eradication method will find applications in the disinfection of pharmaceuticals, biologicals and blood products in the near future

Remote identification of the invasive tunicate Didemnum vexillum using reflectance spectroscopy

Benthic coverage of the invasive tunicate Didemnum vexillum on Georges Bank is largely unknown. Monitoring of D. vexillum coverage is vital to understanding the impact this invasive species will have on the productive fishing grounds of Georges Bank. Here we investigate using reflectance spectroscopy as a method for remote identification of D. vexillum. Using two different systems, a NightSea Dive-Spec and a combination of LED light sources with a hyperspectral radiometer, we collected in-situ measurements of reflectance from D. vexillum colonies. In comparison to reflectance spectra of other common benthic substrates, D. vexillum appears to have a unique spectral signature between 500 and 600 nm. Measuring the slope of the spectrum between these wavelengths appears to be the most robust method for spectral identification. Using derivative analysis or principal component analysis, the reflectance spectra of D. vexillum can be identified among numerous other spectra of common benthic substrates. An optical system consisting of a radiometer, light source, and camera was deployed on a remotely operated vehicle to test the feasibility of using reflectance to assess D. vexillum coverage. Preliminary results, analyzed here, prove the method to be successful for the areas we surveyed and open the way for its use on large-scale surveys

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

Identification of Functionally Distinct Na-HCO3 Co-Transporters in Colon

Na-HCO3 cotransport (NBC) regulates intracellular pH (pHi) and HCO3 secretion in rat colon. NBC has been characterized as a 5,5′-diisothiocyanato-2-2′-stilbene (DIDS)-sensitive transporter in several tissues, while the colonic NBC is sensitive to both amiloride and DIDS. In addition, the colonic NBC has been identified as critical for pHi regulation as it is activated by intravesicular acid pH. Molecular studies have identified several characteristically distinct NBC isoforms [i.e. electrogenic (NBCe) and electroneutral (NBCn)] that exhibit tissue specific expression. This study was initiated to establish the molecular identity and specific function of NBC isoforms in rat colon. Northern blot and reverse transcriptase PCR (RT-PCR) analyses revealed that electrogenic NBCe1B or NBCe1C (NBCe1B/C) isoform is predominantly expressed in proximal colon, while electroneutral NBCn1C or NBCn1D (NBCn1C/D) is expressed in both proximal and distal colon. Functional analyses revealed that amiloride-insensitive, electrogenic, pH gradient-dependent NBC activity is present only in basolateral membranes of proximal colon. In contrast, amiloride-sensitive, electroneutral, [H+]-dependent NBC activity is present in both proximal and distal colon. Both electrogenic and electroneutral NBC activities are saturable processes with an apparent Km for Na of 7.3 and 4.3 mM, respectively; and are DIDS-sensitive with apparent Ki of 8.9 and 263.8 µM, respectively. In addition to Na-H exchanger isoform-1 (NHE1), pHi acidification is regulated by a HCO3-dependent mechanism that is HOE694-insensitive in colonic crypt glands. We conclude from these data that electroneutral, amiloride-sensitive NBC is encoded by NBCn1C/D and is present in both proximal and distal colon, while NBCe1B/C encodes electrogenic, amiloride-insensitive Na-HCO3 cotransport in proximal colon. We also conclude that NBCn1C/D regulates HCO3-dependent HOE694-insensitive Na-HCO3 cotransport and plays a critical role in pHi regulation in colonic epithelial cells

Цифрова трансформація закладу професійної (професійно-технічної) освіти: проблемний аналіз

Modern society is characterized by a significant impact of information technologies on all spheres of human life. In a special way, the processes of digital transformation affect educational institutions, including vocational (vocational and technical) ones. Now vocational (vocational and technical) education occupies an important place in the sector of the country’s economy, prioritizing effective training of highly qualified labourers in the state policy of Ukraine. Nowadays, the professional activity of labourers incorporates an intellectual component related to working with electronic devices, artificial intelligence systems, etc. Monitoring of the labor market shows that a skilled worker of the XXI century should be able to think critically, process information analytically, and work with mechatronics systems. The analysis of the European experience in training qualified workers reflects a certain lag of domestic institutions in terms of digital supply. At the same time, the level of teachers’ digital competence at vocational (vocational and technical) education institutions needs improving. As a result, the issues of digital transformation for educational institutions are urgent and topical. Provision of modern digital equipment, formation and development of digital competence of all participants in the educational space are becoming the main tasks of teaching stuff in the current conditions. In a special way, the tasks set become relevant during the period of quarantine restrictions, when educational institutions mainly work on distance and mixed forms of teaching.Сучасне суспільство характеризується значним впливом інформаційних технологій на всі сфери життя людини. Особливим чином процеси цифрової трансформації впливають на заклади освіти, у тому числі заклади професійної (професійно-технічної) освіти. Наразі професійно-технічна освіта займає важливе місце в секторі економіки країни, пріоритетом у державній політиці України є ефективна підготовка висококваліфікованих кадрів. Нині професійна діяльність робітників включає інтелектуальну складову, пов’язану з роботою з електронними пристроями, системами штучного інтелекту тощо. Моніторинг ринку праці показує, що кваліфікований працівник XXI століття має вміти критично мислити, аналітично обробляти інформацію та працювати з мехатронними системами. Аналіз європейського досвіду підготовки кваліфікованих кадрів відображає певне відставання вітчизняних закладів у цифровому забезпеченні. При цьому рівень цифрової компетентності викладачів у закладах професійної (професійно-технічної) освіти потребує підвищення. Як наслідок, питання цифрової трансформації для навчальних закладів є актуальними та нагальними. Забезпечення сучасним цифровим обладнанням, формування та розвиток цифрової компетентності всіх учасників освітнього простору стають основними завданнями педагогічних колективів в сучасних умовах. Особливо поставлені завдання є актуальними в період карантинних обмежень, коли освітні заклади працюють переважно за дистанційною та змішаною формами навчання