bluuebunny/crossref_metadata_2025 huggingface dataset:
Stroke Severity and Level of Dependence Against Risk of Falls in Stroke Patients
Authors: Wiratmo Puji Astuti , Irvanta Sandi , Narulita Sari
Published: January 2023

A stroke is a neurological disease caused by the blockage or rupture of blood vessels in the brain. Functional dysfunction due to stroke causes stroke patients to be very susceptible to falls. This research aimed to identify the association between the severity of stroke with the level of patient dependence on the risk of falls. This research was a quantitative observational design with a cross-sectional approach. The sample of this study was 66 hospitalized stroke patients who were recruited by quota sampling method. The National Institute of Health Stroke Scale (NIHSS) and Barthel Index are used to measure stroke severity and level of dependence. We assessed the risk of falls using the operational procedure from the hospital. Based on the Spearman rho test, it is found that there is a significant relationship between stroke severity and the level of risk of falls (p=0.000394). Similarly, a significant correlation was found between the level of patient dependence and the level of risk of falls (0.000016). Nurses need to set the nursing care plan for stroke patients who are at risk of falls to prevent further injuries and complications. Continuity of care and family support will help the patient's dependency, reduce the risk of falls, and promote quality of life.
La construcción social del yo
Authors: Peña-Muñante Gonzalo Sebastian
Published: January 2023

Constructos como autoestima, autoconcepto y autoeficacia tienen el mismo prefijo: auto. Lo cierto es que, si bien la raíz etimológica de dichos términos encierra al propio individuo como un yo contenido que intenta verlo todo desde una perspectiva egocéntrica, hay que tener en cuenta al yo como contexto y comprender que las consecuencias que nuestras conductas tienen en el entorno son lo que determina que las volvamos a repetir o, lo que es lo mismo, que se mantengan en el tiempo en forma de hábitos. Estas consecuencias son las respuestas físicas o verbales de las personas ante lo que hacemos, las cuales, por su poder reforzante, nos pueden llevar a buscar la validación de los demás de diversas formas: desde un me gusta en las redes sociales hasta un aprobado en un examen.
FAMILIA ELATINACEAE
Authors: Steinmann Victor W.
Published: January 2023

Familia de plantas dulceacuícolas de amplia distribución mundial con dos géneros (Bergia y Elatine, ambos en México) y unas 50 especies. La familia no es de importancia económica, pero algunas especies de Elatine se cultivan en acuarios. Según datos moleculares, pertenece a los Malpighiales y está relacionada a las Malpighiaceae. Para la región de estudio se reconoce un sólo género con una sola especie.
Efektivitas sirkuit keuangan syariah sebagai media edukasi Simpel Bank Syariah untuk anak usia SD
Authors: Yusron Moh. , Setiyowati Arin , Huda Fatkur
Published: January 2023

Penelitian ini bertujuan untuk menganalisis tingkat efektivitas media SIKUSA dalam upaya meningkatkan literasi keuangan syariah pada anak-anak usia sekolah dasar, khususnya di kawasan Tempurejo Surabaya.  Jenis penelitian yang digunakan adalah studi lapangan dengan pendekatan kualitatif. Teknik pengumpulan data dilaksanakan melalui observasi, wawancara dan dokumentasi. Penelitian ini dilaksanakan di kawasan Tempurejo Surabaya, dan subjek penelitian ini ialah anak usia sekolah dasar kelas 4 hingga kelas 6. Hasil penelitian diperoleh bahwa Sirkuit Keuangan Syariah (SIKUSA) didesain dengan memadukan unsur visual dan motorik anak saat memainkan media ini yakni dengan cara menjalankan mobil menggunakan remote control untuk melewati beberapa pos yang sudah ada tentang alur menabung di bank syariah. Setiap memasuki suatu pos, mobil harus berhenti, lalu pemain SIKUSA harus membaca hingga mensimulasikan perintah maupun tahapan dalam pos tersebut. Karena poses edukasi dilakukan sambil bermain dan simulasi secara langsung, maka media SIKUSA ini menunjukkan efektivitasnya sebagai media edukasi simpanan pelajar (SimPel) bank syariah dan meningkatkan literasi keuangan syariah bagi anak usia sekolah dasar (SD) di Tempurejo Surabaya. This study aims to analyze the effectiveness of SIKUSA media in improving Islamic financial literacy in elementary school-age children, especially in the Tempurejo area of Surabaya. The type of research used is a field study with a qualitative approach. Data collection techniques were carried out through observation, interviews, and documentation. This research was conducted in the Tempurejo area of Surabaya, and the subjects in this study were elementary school-aged children in grades 4 to 6. The results showed that the Islamic Financial Circuit (SIKUSA) was designed by combining visual and motorik elements of children when playing this media, namely by running the car using a remote control to pass through several existing posts regarding the flow of saving in Islamic banks. Every time they enter a post, the car must stop, then the SIKUSA player must read to simulate the commands and stages in the post. Because the educational process is carried out while playing and simulating directly, the SIKUSA media shows its effectiveness as an educational media for Islamic bank student savings (SimPel) and increases Islamic financial literacy for elementary school-aged children (SD) in Tempurejo Surabaya.
Kendala siswa dalam mengatasi kesulitan belajar Trigonometri: Youtube sebagai sumber belajar Matematika
Authors: Sugianto Rahmad , In’am Akhsanul , Syaifuddin Mohammad
Published: January 2023

YouTube platform video-sharing sebagai sumber belajar pada semua mata pelajaran yang sesuai topik yang dicari. Tujuan pada penelitian ini adalah untuk mengetahui bagaimana cara mengeksplorasi kanal Youtube sebagai sumber belajar siswa pada mata pelajaran matematika materi trigonometri di kelas X SMA. Jenis penelitian deskriptif kuantitatif, instrumen yang digunakan adalah angket eksplorasi materi trigonometri dengan skala likert. Populasi yang digunakan adalah seluruh siswa di SMA dengan jumlah 500, dengan kelas X sebagai sampel menggunakan metode slovin yaitu 80 orang. Teknik pengumpulan data yang digunakan berupa angket yang dibagikan kepada siswa dengan google form menggunakan fitur survey. Instrumen yang dikembangkan telah divalidasi dan diuji tingkat reliabilitasnya oleh 2 dosen dan 2 praktisi menggunakan uji Q-Cochran baik dari segi muka dan isi. Hasil skor uji test untuk validasi pada statistik Asym.sig menunjukkan nilai sebesar 0.417, dan skor 0.724 untuk tingkat reliabel dengan kategori sangat tinggi. Hasil dari penelitian ini mengeksplorasi kanal Youtube sebagai sumber belajar siswa pada trigonometri.  Hasil angket pada penelitian menunjukkan bahwa 81,65 % menggunakan kanal youtube sebagai sumber belajar tambahan untuk menyelesaikan tugas pada materi trigonometri dengan kategori sangat positif.YouTube is a video-sharing platform as a learning resource in all subjects that match the topics you are looking for. This study aimed to discover how to explore the YouTube channel as a learning resource for students in trigonometry in class X SMA. In this type of quantitative descriptive research, the instrument used is an exploratory questionnaire on trigonometry material with a Likert scale. The population used was all high school students with a total of 500, with class X as the sample using the Slovin method, namely 80 people. The data collection technique used is in the form of a questionnaire which is distributed to students with a Google Form using the survey feature. The developed instrument has been validated and tested for its reliability level by two lecturers and two practitioners using the Q-Cochran test in terms of face and content. The results of the test scores for validation on the Asym.sig statistics show a value of 0.417 and a score of 0.724 for a reliable level with a very high category. The results of this study explore the Youtube channel as a source of student learning in trigonometry. The questionnaire results in the study showed that 81.65% used the YouTube channel as an additional learning resource to complete assignments on trigonometry material in a very positive category.
“Regra Tácita”
Authors: Arruda Jalusa Silva de , Figueiredo Otto Vinicius Agra , Santos Edmar Ferreira
Published: January 2023

O artigo é desdobramento de pesquisa desenvolvida em Salvador e nove municípios do Recôncavo Baiano, que teve por objetivo identificar percepções e sentidos sobre racismo, sexismo e intolerância religiosa, especialmente praticada contra crianças, adolescentes e jovens. Neste momento, objetiva-se analisar a percepção de atos e práticas identificados como intolerância religiosa no ambiente escolar, pois foi recorrente a menção à escola como lócus dessa forma de violência. Para tanto, considera-se racismo religioso como categoria analítica, uma vez que, no Brasil, discriminações e violências praticadas contra grupos religiosos são predominantemente dirigidas às religiões de matriz africana. Os dados indicam interdições específicas para crianças, adolescentes e jovens de religiões afro-brasileiras, bem como práticas associadas ao bullying que desvelam o racismo religioso institucionalizado na escola, em detrimento de um projeto político pedagógico antirracista.
Inclusão e Violência Escolar
Authors: Mefano Vania , Lopes Marina Maldonado , Vermelho Sonia Cristina Soares Dias
Published: January 2023

O presente artigo traz resultado da pesquisa “Violência Escolar: discriminação, bullying e responsabilidade” com objetivo de analisar a relação entre inclusão e violência escolar, sob a forma do preconceito e do bullying. A metodologia foi de cunho quanti-qualitativo, com coleta de dados em 2019 por meio de questionários aplicados a 217 alunos do 9º ano do Ensino Fundamental em cinco escolas públicas da cidade do Rio de Janeiro. Os resultados indicaram correlação entre o grau de inclusão e o preconceito (-0,87) e grau de inclusão e maus tratos sofridos (-0,46), ou seja, quanto mais ações de inclusão nas escolas, menor a tendencia a ter manifestações de preconceito por parte dos alunos e menos maus tratos entre eles. Este estudo, assim como na Teoria Crítica, ressaltam a importância das ações de inclusão nas escolas como forma de combate à violência escolar, tanto em termos de preconceito quanto em termos de maus tratos.
Aprendizagens Colaborativas Mediadas pelo Dispositivo para Ensino Híbrido SSC
Authors: Conceição Sheilla Silva , Schneider Henrique Nou
Published: January 2023

Este artigo faz parte da pesquisa de tese realizada no âmbito do Programa de Pós-graduação em Educação, da Universidade Federal de Sergipe, tendo por objetivo geral compreender os processos de ensino-aprendizagem híbridos por meio do dispositivo SSC no ensino fundamental dos anos finais. Trata-se de uma pesquisa de natureza qualitativa sob a égide da pesquisa-ação-intervenção por tornar possível a mediação e construção dos processos de aprendizagem. A Análise Textual Discursiva (ATD) baseou-se em Moraes e Galiazzi (2016), que culminou em categorias emergentes. Os sujeitos participantes da pesquisa foram 39 alunos e 2 professores de duas escolas da rede pública municipal em Aracaju/SE e São Leopoldo/RS. As análises confirmaram a articulação do ensino híbrido com os processos de aprendizagem, o que favoreceu a construção do conhecimento colaborativo, ao passo que provocou rupturas na prática pedagógica dos professores. Assim, o dispositivo para ensino híbrido SSC contribui para os encaminhamentos dos processos de ensino-aprendizagem colaborativos e dialógicos.
Concepções de Professores Sobre Bulliyng e Formas de Enfrentamento no Contexto Escolar
Authors: Souza Lucimêre Rodrigues De , Santos Jaciete Barbosa dos , Dias Viviane Borges
Published: January 2023

A violência escolar é fenômeno antigo que se conserva através do tempo. Na contemporaneidade vem sendo relatada outra forma de violência no ambiente escolar que tem tomado dimensões cada vez maiores, denominada bullying. Trata-se de uma intimidação psicológica ou física, intencional e reincidente, dirigida a uma pessoa vista como frágil por seus agressores. A escola parece contribuir com a existência dessa forma de violência ao fomentar a reprodução de práticas sociais que obstam o acolhimento da diversidade humana. O presente artigo objetivou analisar as concepções de docentes do estado da Bahia sobre o bullying, identificando conceitos atribuídos a tal fenômeno, bem como possíveis formas de enfrentamento no contexto escolar. As análises foram realizadas por meio das entrevistas com os professores de escolas públicas de duas cidades baianas, marcadas por alto índice de violência. Percebeu-se a inexistência de uma clareza conceitual sobre o bullying e, em alguns casos, uma relativização das situações identificadas como algo comum ao cotidiano escolar ou visto como brincadeira por parte dos professores. Identificaram-se possíveis formas de enfrentamento a partir das concepções apresentadas. Percebe-se que o contexto escolar é parte da cultura e acaba sendo (re)produtor de violência.
Entre Tantas Violências
Authors: Ferreira Luciana Haddad , Barbosa Andreza , Barros Gabriel Meneses
Published: January 2023

O artigo discute a relação entre o aumento da violência escolar, observada em 2021 e 2022, com a descaracterização da escola como lugar de pertença. Para tanto, recorremos à análise das políticas educacionais recentemente implementadas na rede estadual paulista, juntamente com os dados de violência referentes aos primeiros meses de retorno ao ensino presencial. Trazemos também as escritas narrativas de um educador da rede estadual de educação, cujos registros possibilitam extrapolar os dados numéricos e adentrar à realidade do que tem sido vivido no cotidiano das escolas. As análises evidenciam que há uma complexidade de fatores que contribuem para o aumento dos casos de violência, dentre os quais destacamos as condições precárias estabelecidas por políticas educacionais que esvaziam a escola de seu sentido e oferecem soluções simples para problemas complexos. Ainda, sinalizamos possibilidades de restituição do sentido da escola como lugar de convívio e produção de conhecimento.
Phase transformations in composite films of the system Se-Cu, obtained using explosive crystallization and thermal annealing
Authors: Kogai V. Ya.  , Mogileva T. N.  , Fateev A. E.  , Mikheev G. M.
Published: January 2023

The results of experimental studies of the phase transformation in composite films of the Se-Cu system obtained in vacuum as a result of the sequential thermal deposition of selenium and copper on a glass substrate are presented. At a fixed thickness of the selenium layer (45 nm), the effect of the thickness of the copper layer (40-115 nm) on the phase composition of the synthesized films formed as a result of explosive crystallization occurring during the interaction of hot copper clusters with low-melting selenium was studied. It was found that the subsequent thermal annealing of the synthesized films is accompanied by a significant change in their phase composition and optical transmission spectra. Keywords: phase transformations, composite films of the Se-Cu system, explosive crystallization, thermal annealing, optical properties.
Polarization processes in thin layers of glassy hybrid system Ge-=SUB=-28.5-=/SUB=-Pb-=SUB=-14.0-=/SUB=-Fe-=SUB=-1.0-=/SUB=-S-=SUB=-56.5-=/SUB=-
Authors: Castro-Arata  R. A.  , Grabko G. I.  , Kononov A. A.  , Anisimova N. I.  , Krbal M.  , Kolobov A. V.
Published: January 2023

The results of the investigations of the polarization properties in thin layers of vitreous Ge28.5Pb14.0Fe1.0S56.5 are presented. A process of dipole-relaxation polarization was discovered, the activation energy of which turned out to be equal to Ea=(0.97±0.14) eV. It has been determined that charge transfer in the Ge28.5Pb14.0Fe1.0S56.5 hybrid system is a thermally activated process with an activation energy of Ea=(0.54±0.01) eV. The calculation results allow us to conclude that the glass-forming capacity of the (Ge28.5Pb15.0S56.5)100-xFex system decreases linearly with an increase in the proportion of metal in the glass structure. Keywords: charge carrier hopping, thin layers, hybrid chalcogenide, lone-pair electrons.
Correlation of the electronic and atomic structure at passivated n-InP(100) surfaces
Authors: Lebedev M. V.  , Lvova T. V.  , Smirnov A. N.  , Davydov V. Yu.  , Koroleva A. V.  , Zhizhin E. V.  , Lebedev S. V.
Published: January 2023

Photoluminescence, Raman spectroscopy and X-ray photoelectron spectroscopy are used to study electronic and atomic structure of n-InP(100) surfaces treated with different sulfide solutions. It is shown that the sulfide treatment causes removal of the native oxide layer from the semiconductor surface and formation of the passivating layer consisting of In-S chemical bonds with the structure dependent on the solution composition and atomic arrangement at the initial surface of the semiconductor. This is accompanied by an increase in photoluminescence intensity and narrowing of the surface depletion layer. Atomic structure of the passivating layer determines the total dipole that modifies the depth distribution of the bands potentials and thus the surface electronic structure. Keywords: surface modification, sulfur passivation, Raman spectroscopy, photoluminescence, X-ray photoelectron spectroscopy.
Determination of the flow and activation energy of phosphorus desorption during annealing of an InP(001) substrate in an arsenic flux under molecular beam epitaxy conditions
Authors: Kolosovsky D. A.  , Dmitriev D. V.  , Ponomaarev S. A.  , Toropov A. I.  , Zhuravlev K. S.
Published: January 2023

We report experimental study of phosphorus desorption from epi-ready InP(001) substrates during high-temperature annealing in an arsenic flux. InPAs solid solution and InAs islands are formed on the surface in the process of annealing. The original method is proposed to determine the amount of phosphorus atoms desorbing from the surface by determining the amount of arsenic atoms in the solid solution of InPAs and InAs islands. The flux of phosphorus desorbing from the surface increases from 1·10-4 monolayer · cm-2·s-1 at 500oC annealing temperature to 7.3·10-4 monolayer · cm-2· s-1at 540oC. The activation energy of the phosphorus desorption process is 2.7±0.2 eV. Keywords: InP, annealing, desorption, activation energy.
Effect of Hydrogen Implantation Dose on the Relaxation of Electrophysical Characteristics of Silicon-on-Insulator Structures after Exposure to X-rays
Authors: Abrosimova N.D.  , Yunin P. A.  , Drozdov M.N.  , Obolenskii S.V.
Published: January 2023

Experimental studies of the relaxation of electrophysical parameters of SOI structures with different doses of hydrogen implantation after exposure to stationary X-ray radiation are presented. Investigation of high-frequency CV characteristics and pseudo-MOS transistors made it possible to obtain information about the accumulated charge, the density of surface states, mobility of carriers. The impurity composition and depth profile of hydrogen concentration were determined by the SIMS method. Structural perfection of the layers and interfaces was evaluated using the XRR and XRD methods. A different nature of the relaxation dependence and the recovery time of the electrophysical parameters for SOI structures with different doses of hydrogen implantation are recorded. The values of mobility and charge density are higher for the structure with a lower hydrogen implantation dose. Keywords: Ion implantation, silicon on insulator, radiation resistance, X-ray diffraction, pseudo-MOS transistor, residual hydrogen, SIMS.
Investigation of the influence of the ion-beam treatment dose of the Si(111) surface on the GaAs nanowires growth processes
Authors: Shandyba N. A.  , Chernenko N. E.  , Balakirev S. V.  , Eremenko M. M.  , Kirichenko D. V.  , Solodovnik M. S.
Published: January 2023

This paper presents the results of experimental studies of the effect of the Ga ion dose during ion-beam treatment of the Si(111) surface using the focused ion beam technique on the Ga+ nanowires epitaxial growth processes. A significant difference is revealed between the parameters of nanowire arrays formed on modified and unmodified areas of the Si substrate in this way. It is shown that changing the Ga ions dose from 0.052 to 10.4 pC/μm2 during ion-beam treatment makes it possible to form GaAs nanowires arrays with a different set of parameters in a single technological cycle with a high degree of localization. The regularities of the influence of the dose of Ga ions during surface modification on the key characteristics of GaAs nanowires (density, diameter, length, and orientation with respect to the substrate surface) are experimentally established. Keywords: Focused ion beam, nanowires, GaAs, molecular beam epitaxy.
Formation of heterostructures with multiple quantum wells InN/InGaN by the PA-MBE method on sapphire
Authors: Kalinnikov M.A.  , Lobanov D.N.  , Kudryavtsev K.E.  , Andreev B. A.  , Yunin P.A.  , Krasilnikova L.V.  , Novikov A.V.  , Skorokhodov E.V.  , Krasilnik Z.F.
Published: January 2023

The features of the process of growth of multilayer heterostructures with InN/InGaN quantum wells (QWs) by the method of molecular-beam epitaxy with nitrogen plasma activation in the mode of modulated metal fluxes are studied. To compensate for elastic stresses in the structure, the active region was formed in the form of an InN/InGaN superlattice matched over the average lattice parameter with the underlying InGaN buffer layer. It has been shown that during the growth of relatively narrow InN QWs up to 3 nm wide, there is no relaxation of elastic stresses in the active region of the structure, and the dislocation density remains at the level N_D~(3-4)·1010 cm-2, which corresponds to the dislocation density in InGaN-buffer. Such structures demonstrate the most intense PL in the wavelength range of 1.3-1.5 μm. With the growth of wider QWs, the imperfection of the structures sharply increases (N_D>1011 cm-2), which is accompanied by a decrease in the emission intensity. The structures grown with InN/InGaN QWs demonstrated an order of magnitude better temperature stability of PL compared to bulk InN layers (PL quenching by ~3 and ~25 times, respectively, in the temperature range of 77-300 K). Nevertheless, at a low temperature (T=77 K), the PL intensity of the studied structures with InN/InGaN QWs is noticeably inferior to that for the bulk InN layer, which apparently indicates a significant role of nonradiative recombination by the Shockley--Reed--Hall mechanism in structures with QWs (as opposed to Auger recombination in bulk InN). Keywords: indium and gallium nitride, molecular beam epitaxy, quantum well, photoluminescence, dislocations.
Internal loss in diode lasers with quantum well-dots
Authors: Zhukov A. E.  , Nadtochiy A. M.  , Kryzhanovskaya N. V.  , Shernyakov Yu. M.  , Gordeev N. Yu.  , Serin A. A.  , Mintairov S. A.  , Kalyuzhnyy N. A.  , Payusov A. S.  , Kornyshov G. O.  , Maximov M. V.  , Wang Y.
Published: January 2023

The internal loss at the lasing threshold were studied experimentally and numerically in laser cavities comprising dense arrays of InGaAs/GaAs quantum dots (quantum well-dots) as a function of the number of their planes and the output loss. Numerical values of the parameters were found that determine the free-carrier absorption in the active region and in the waveguiding layer. The optimal design of the laser diode was determined to achieve the highest external differential efficiency. Keywords: diode lasers, semiconductor nanostructures, internal loss.
The influence of the waveguide layer composition on the emission parameters of 1550 nm InGaAs/InP laser heterostructures
Authors: NovikovI.I.  , Nyapshaev I.A.  , Gladyshev A. G.  , Andryushkin V. V.  , Babichev A. V.  , Karachinsky L. Ya.  , Shernyakov Yu. M.  , Denisov D.V.  , Kryzhanovskaya N. V.  , Zhukov A.E.  , Egorov A.Yu.
Published: January 2023

The influence of InGaAlAs waveguide composition on the photoluminescence and electroluminescence of 1550 nm spectral range heterostructures based on thin strained In0.74Ga0.26As quantum wells has been studied. An approach is proposed that allows based on the analysis of electroluminescence to carry out a comparative analysis of the deferential gain in fabricated laser diodes. It is shown that decrease of the molar fraction of aluminum in waveguide InGaAlAs layers matched in lattice constant with InP leads to falling of integrated photoluminescence intensity, however, laser diodes with In0.53Ga0.31Al0.16As waveguide layers demonstrate a higher differential gain compared to laser diodes with In0.53Ga0.27Al0.20As waveguide. Keywords: quantum well, molecular-beam epitaxy, photoluminescence, electroluminescence.
Structural and gas-sensitive characteristics of thin semiconductor PdO films of various thicknesses during ozone detection
Authors: Ryabtsev S. V.  , Ghareeb D. A. A.  , Turishchev S.Yu.  , Obvintseva L. A.  , Shaposhnik A. V.  , Domashevskaya E. P.
Published: January 2023

PdO films were obtained by thermal deposition of palladium metal with a thickness of 30 and 90 nm, followed by its oxidation in air at different temperatures. PdO oxide films are characterized by transmission electron microscopy (TEM) and reflection high-energy electron diffraction (RHEED). Data on the semiconductor properties and gas sensitivity to different concentrations of ozone in the air are obtained. The optimal temperature conditions for the oxidation of the films are established, which ensure their uniform phase composition and the absence of electrical noise during the detection of gases. The mechanism of the electrical noise appearance in ultrathin films associated with their fragmentation during oxidative annealing is proposed and justified. The possibility of detecting ozone impurities in the air below the maximum permissible concentration (MPC) by PdO semiconductor films is shown. Keywords: palladium oxide thin films, phase composition, electrical noise, gas sensor properties.
Optical and Structural Properties of Hg-=SUB=-0.7-=/SUB=-Cd-=SUB=-0.3-=/SUB=-Te Epitaxial Films
Authors: Andryushchenko D.A.  , Ruzhevich M.S.  , Smirnov A. M.  , Bazhenov. N.L.  , Mynbaev K.D.  , Remesnik V.G.
Published: January 2023

The results of comparative studies of the optical and structural properties of Hg0.7Cd0.3Te bulk crystals and epitaxial films grown by various methods are presented. The data of photoluminescence studies performed in the temperature range 4.2-300 K showed the similarity of the optical properties of different samples and indicated a significant disordering of the solid solution. According to X-ray diffraction data, however, the scale of the disordering was not directly related to the structural quality of the material. The prospects for using the material grown by various methods in optoelectronics applications are discussed. Keywords: HgCdTe, defects, luminescence, X-ray diffraction.
Influence of rapid thermal annealing on the distribution of nitrogen atoms in GaAsN/GaAs
Authors: Lazarenko A. A.  , Shubina K. Yu.  , Nikitina E. V.  , Pirogov E. V.  , Mizerov A. M.  , Sobolev M. S.
Published: January 2023

The article investigates the effect of rapid thermal annealing of ternary GaAs1-xNx/GaAs solid solutions on the distribution of nitrogen atoms in the crystal lattice. The samples are studied by photoluminescence spectroscopy and high-resolution X-ray diffractometry. Due to the size and electronegativity mismatch of nitrogen and arsenic atoms, nitrogen is incorporated unevenly into the GaAs crystal lattice. Options of the nitrogen atoms arrangement in the GaAs crystal lattice before and after rapid thermal annealing are shown. Keywords: dilute nitrides, heterostructures, molecular-beam epitaxy, GaAs, nitrogen.
Investigation of methods for texturing light-emitting diodes based on AlGaAs/GaAs heterostructures
Authors: Malevskaya A. V.  , Il’inskaya N. D.  , Kalyuzhnyy N. A.  , Malevskiy D. A.  , Zadiranov Y. M.  , Pokrovskiy P. V.  , Blokhin A. A.  , Andreeva A. V.
Published: January 2023

Investigations of methods for texturing the light-emitting surface of IR light-emitting diodes (LEDs) (wavelength 850 nm) based on AlGaAs/GaAs heterostructures with Bragg reflectors have been carried out. Developed were methods of liquid and plasma-chemical etching of solid solution for creating peaks (pyramids) of different form, 0.2-1.5 μm height. Estimation of the effect of texturing methods and also configuration of peaks on the light-emitting diode electroluminescence intensity has been performed. The increase of the electroluminescence intensity by 25% has been achieved. Keywords: light-emitting diode, texturing, etching methods, electroluminescence.
Influence of quantum well parameters on the spectrum of two-dimensional plasmons in HgTe/CdHgTe heterostructures
Authors: Aleshkin V. Ya.  , Dubinov A. A.
Published: January 2023

Influence of parameters of a quantum well and electronic polarizability spatial dispersion on the dependence of two-dimensional plasmon energy on wave vector in narrow-gap CdHgTe quantum wells (band gap 35 meV) is studied theoretically. It is shown that at energies above 20 meV, the dispersion law of two-dimensional plasmons is close to linear. Taking into account the finite width of the quantum well decreases the plasmon phase velocity. This effect increases with an increase in the fraction of cadmium in the QW while maintaining the band gap and with a decrease in the concentration of charge carriers in it. Keywords: two-dimensional plasmon, narrow-gap HgTe.
X-ray diffraction and differential scanning calorimetry analysis of CuInZnSe-=SUB=-3-=/SUB=-
Authors: Ibrahimova  S. I.  , Jabarov S. H.  , Guseynov G. G.  , Guliyeva Kh. M.  , Mirzayev M. N.  , Aliyev Yu.I .
Published: January 2023

The compound CuInZnSe3 was synthesized, the crystal structure was investigated by X-ray diffraction and thermal properties was investigated by differential scanning calorimetry analysis. It was found that, under normal conditions, the crystal structure of this compound corresponds to cubic symmetry with the space group F-43m (216). The temperature dependence is obtained at a constant rate of heat treatment of the heat flow in the temperature range T=30-900oC. The observed endothermic effects at T=43, 600 and 756oC are explained by the resonance of thermal vibrations of atoms in the crystal structure of the CuInZnSe3 compound and the release of relatively weakly bound atoms. Keywords: X-ray diffraction, semiconductors, chalcogenides.
XVII Interstate Conference Thermoelectrics and Their Applications --- 2021" (ISCTA 2021 St. Petersburg, September 13-16, 2021 Obtaining and investigation of ohmic contacts with high adhesion to thermoelements
Authors: Shtern M.Yu.  , Kozlov A.O.  , Shtern Yu.I.  , Rogachev M.S.  , Korchagin E.P.  , Mustafoev B.R.  , Dedkova A.A.
Published: January 2023

The factors determining the adhesive strength of film coatings are considered. The functions of contacts in thermoelements used in a wide temperature range were determined. It was established that the adhesive strength of contact is a limiting factor in the mechanical strength of a thermoelement. A method of vacuum sputtering of thin-film contacts was proposed, including the surface treatment of samples of thermoelectric materials. The presence of a transition layer in the area of the metal-thermoelectric material contact, formed during the interaction of the metal with elements of the thermoelectric material, was established. The dependence of the adhesive strength of film contact on roughness of surface on which they formed was established. Thermal stable contacts for thermoelements with low resistivity of the order of 10-9 Ω·m2 and high adhesion strength of at least 12 MPa were obtained by ion-plasma sputtering. Keywords: thermoelements, contacts, thin films, adhesion, contact resistance.
Multi-section thermoelements, advantages and problems of their creation
Authors: Shtern M.Yu.
Published: January 2023

In this work, the ways of increasing the efficiency of thermoelectric generators are considered. These include an increase in the figure of merit of thermoelectric materials, as well as an increase in the temperature difference between hot and cold junctions of thermoelements and, accordingly, the range of their operating temperatures. The expediency of using thermoelements with multi-section legs has been substantiated. For their creation, effective thermoelectric materials with operating temperatures in the range of 300-1200 K have been proposed. A technique for modeling such thermoelements has been developed. Structures and materials of effective contact systems for multi-section thermoelements have been proposed, a technology for their manufacture has been developed. Ways of switching sections in thermoelement legs are considered. The thermal expansion of thermoelectric materials is investigated and a method for damping thermal stresses in the design of a thermoelement is proposed. The problem of thermoelectric material sublimation at high temperatures was solved by using protective coatings. Key words: thermoelectric generators, multi-section thermoelements, thermoelectric materials, thermal and electrophysical properties, contact systems, protecting coatings.
Theoretical investigation of the phonon spectrum and the lattice thermal conductivity in GeTe.
Authors: Pshenay-Severin D.  , Shabaldin A.  , Konstantinov P.  , Burkov A.
Published: January 2023

Recently, there has been renewed interest in thermoelectric materials based on germanium telluride, which demonstrate high efficiency in mid-temperature range. This paper discusses the theoretical description of the phonon spectrum and lattice thermal conductivity in GeTe using ab initio methods. Using these methods, the temperature dependence of the lattice thermal conductivity in the rhombohedral phase was calculated and effects of scattering by point defects and nanostructuring were estimated. The modification of the phonon spectrum upon the transition to the high-temperature cubic phase is investigated. The calculated temperature dependences of the lattice thermal conductivity are compared with the available experimental data on GeTe and its solid solutions. Keywords: germanium telluride, ab initio calculations, phonon spectrum, lattice thermal conductivity, nanostructuring.
Synthesis, structure and anisotropy of thermoelectric properties of Bi-=SUB=-2-=/SUB=-Te-=SUB=-2.7-=/SUB=-Se-=SUB=-0.3-=/SUB=- compound doped with samarium
Authors: Yapryntsev M. N.  , Ivanov O. N.  , Vasil’ev A. E.  , Zhezhu M. V.  , Popkov D. A.
Published: January 2023

We study crystallographically textured thermoelectric materials with electronic conductivity based on bismuth telluride doped with samarium (Bi2-xSmxTe2.7Se0.3, where x=0, 0.05, 0.02, 0.05) obtained by the method of solvothermal synthesis and double pressing by the method of spark plasma sintering. The crystallographic texture was achieved by the spark plasma sintering of plate-like nanoparticles. The texturing axis [001] coincided with the direction of compression in the of spark plasma sintering process. An increase in the samarium concentration leads to a decrease in the radial size of the synthesized nanoplates, which facilitates the processes of rotation and sliding of particles relative to each other during pressing and, as a consequence, an increase in the anisotropy factor characterizing the degree of preferred grain orientation in the bulk material. Samarium doping affects the particle size of the initial powder, the average grain size in the bulk material and, as a consequence, the thermoelectric properties. It was found that the maximum of thermoelectric figure of merit weakly depends on the samarium content and falls in the range of ~(0.6-0.7), while the temperature position of the maxima noticeably shifts to higher temperatures with an increase in the Sm content. Keywords: thermoelectric materials, bismuth telluride, spark plasma sintering, texturing, anisotropy in properties.
Magnetic properties of Pb-=SUB=-1-y-=/SUB=-Sc-=SUB=-y-=/SUB=-Te alloys
Authors: Skipetrov E.P.  , Bogdanov E.V.  , Skipetrova L.A.  , Solovev A.A.  , Knotko A.V.
Published: January 2023

The magnetic field dependences of the magnetization (B≤9 T, T=2-70 K) of the samples from a single crystal Pb1-yScyTe (y=0.01) ingot, synthesized by the Bridgman method, are studied. It is established that, in accordance with the generally accepted model of the rearrangement of the electronic structure of alloys during doping, there is no paramagnetic contribution of single scandium ions located in the nodes of the metal sublattice in the studied samples. The magnetization of the samples contains several contributions: superparamagnetism of scandium clusters, linear in field diamagnetism of the crystal lattice and the paramagnetism of free electrons, as well as the oscillating contribution of the de Haas--van Alphen effect. The field dependences of the main contribution of scandium clusters are successfully approximated using the Langevin function. The average concentration, magnetic moment and the total magnetic moment of the clusters per unit volume of the sample were determined with an increase in the impurity concentration along the ingot. Keywords: PbTe-based alloys, 3d-transition metal impurities, rearrangement of electronic structure, field dependences of magnetization, superparamagnetism of scandium clusters.
Registration of terahertz irradiation with silicon carbide nanostructures
Authors: Bagraev N. T.  , Kukushkin S. A.  , Osipov A. V.  , Klyachkin L. E.  , Malyarenko A. M.  , Khromov V. S.
Published: January 2023

The response to external terahertz (THz) irradiation from the silicon carbide nanostructures prepared by the method of substitution of atoms on silicon is investigated. The kinetic dependence of the longitudinal voltage is recorded at room temperature by varying the drain-source current in the device structure performed in a Hall geometry. In the frameworks of proposed model based on the quantum Faraday effect the incident radiation results in the appearance of a generated current in the edge channels with a change in the number of magnetic flux quanta and in the appearance of features in the kinetic dependence of the longitudinal voltage. The generation of intrinsic terahertz irradiation inside the silicon carbide nanostructures is also revealed by the electrically-detected electron paramagnetic resonance (EDEPR) measured the longitudinal voltage as a function of the magnetic field value. Keywords: silicon carbide on silicon, terahertz irradiation, nanostructure, electrically-detected EPR, quantum Faraday effect.
Influence of the asymmetry of the metal mask arrangement on the matching of the lower electrode with a high-frequency displacement generator during reactive-ion etching of massive substrates
Authors: Poletayev S. D.  , Lyubimov A. I.
Published: January 2023

The effect of the degree of asymmetry in the arrangement of metal masks on the matching of the lower electrode with a high-frequency displacement generator during selective reactive-ion etching of massive substrates in plasma-forming gas mixtures based on freon-14 is studied theoretically and experimentally. Theoretically, the absence of the influence of the asymmetry of the mask location on the specific reactive power is shown. It is shown that at the edge of the substrate, especially with a mask, there is a sharp increase in the RF current density, which proves mainly the surface (end) nature of its flow. The influence of the mask location on the behavior of the electric charge density, which correlates with the distribution of the RF current density in the near-surface layer of the substrate, is established. No redistribution of the charge density of the chemically active plasma particles at the edge of the mask was detected. In accordance with the theoretical results obtained, it is experimentally shown that metal masks with a side length ratio of 36/0 mm reduce the power reflection coefficient within 5%. Keywords: diffractive optical element, reactive ion etching, inductively coupled plasma, contact mask, lower electrode, simulation Multiphysics.
ECG Signal Recognition Based on Lookup Table and Neural Networks
Authors: Al-Ani Muzhir Shaban
Published: January 2023

Electrocardiograph (ECG) signals are very important part in diagnosis healthcare the heart diseases. The implemented ECG signals recognition system consists hardware devices, software algorithm and network connection. An ECG is a non-invasive way to help diagnose many common heart problems. A health-care provider can use an ECG to recognize irregular heartbeats, blocked or narrowed arteries in the heart, whether you have ever had a heart attack, and the quality of certain heart disease treatments. The main part of the software algorithm including the recognition of ECG signals parameters such as P-QRST. Since the voltages at which handheld ECG equipment operate are shrinking, signal processing has become an important challenge. The implemented ECG signal recognition approach based on both lookup table and neural networks techniques. In this approach, the extracted ECG features are compared with the stored features to recognize the heart diseases of the received ECG features. The introduction of neural network technology added new benefits to the system implementing the learning and training process.
Actualización del Plan Estratégico de Ciencia, Tecnología, e Innovación del sector Agropecuario PECTIA 2017 - 2027 : departamento de Putumayo 2022
Authors:   Secretaría de Agricultura, Medio Ambiente y Productividad, Bogotá (Colombia),   Ministerio de Agricultura y Desarrollo Rural, Bogotá (Colombia),   Gobernación de Putumayo,   Corporación Colombiana de Investigación Agropecuaria, AGROSAVIA
Published: January 2023

Este documento contiene los resultados del proceso de actualización del Pectia y la Agenda I+D+i que lo integra, en el departamento de Putumayo.
Actualización del Plan Estratégico de Ciencia, Tecnología, e Innovación del sector Agropecuario PECTIA 2017 - 2027 : Departamento de Cauca 2022
Authors:   Ministerio de Agricultura y Desarrollo Rural, Bogotá (Colombia),   Corporación Colombiana de Investigación Agropecuaria - AGROSAVIA
Published: January 2023

En el Departamento, el sector de la agricultura está basado principalmente en la producción agrícola y ganadera, la explotación forestal y la actividad pesquera, el cual representa en el departamento del Cauca uno de los mayores aportes a la economía de la región con un 12,92% de participación dentro del PIB departamental (CÁMARA DE COMERCIO DEL CAUCA, 2019). El departamento del Cauca por sus condiciones geográficas y características competitivas traducidas en productividad ha logrado mantener un crecimiento en el PIB a la par que el de nivel nacional, logrando así que el valor agregado de los diferentes sectores económicos se traduzca en mayores oportunidades y beneficios para la región, estimulando la inversión e incrementando la renta per cápita de los caucanos (CÁMARA DE COMERCIO DEL CAUCA, 2019).
Satisfaction of a Virtually Delivered Supervised Exercise Program Specific to Breast Cancer Survivors on Endocrine Therapy
Authors: Fujita Rafael Akira , Myers Sam , Mackenzie Kelly , LeVasseur Nathalie , Faulkner Guy , Campbell Kristin
Published: January 2023

Background

Only 11% of breast cancer survivors currently meet the exercise oncology guidelines, and the restrictions to gyms and time outside of home related to the COVID-19 pandemic may have aggravated this situation. To address this, we are testing the efficacy of a twice-weekly, 8-week, supervised, synchronous exercise program delivered virtually for participants diagnosed with breast cancer, called the BE-FIT program.

Objective

The aim of this paper is to examine the preliminary participant's satisfaction in participating in the BE-FIT program.

Methods

Participants are asked to complete a “Participant Satisfaction Questionnaire” using a range of 1-5 for each question (1 represents “very difficult,” 2 “difficult,” 3 “neutral,” 4 “easy,” and 5 “very easy”). The questions were related to the following: level of difficulty to access classes; level of clarity of information received during classes; level of capacity to continue practicing exercises independently after finishing the exercise program; and level of how likely one would recommend the program to a friend.

Results

For the ongoing efficacy trial, we collected responses from 40 participants. The participants reported that it was “very easy” and “easy” to access and participate in the virtual exercise session (63% and 37%, respectively). When asked if the information received from the exercise training was clear and easy to understand during virtual exercise sessions, 93% reported “very easy,” and the remainder reported “easy.” Regarding continuing the exercise independently with the content learned in the program, 87% of the participants reported “very easy” or “easy” (31% and 56%, respectively), and 13% reported “neutral.” Lastly, 80% of participants reported “very easy” to recommend the BE-FIT program to a friend, 18% reported “easy,” and 2% reported “neutral.”

Conclusions

A virtually delivered supervised program seems to be an excellent alternative to in-person supervised exercise programs to provide easy access and clear information during the classes with potential influence on the future practice of exercises.

Conflicts of Interest

None declared.

Trial Registration

ClinicalTrials.gov NCT04824339; https://clinicaltrials.gov/ct2/show/NCT04824339
Analysis of Public Health on Facebook Posts in Ghana Using Topic Modelling (Preprint)
Authors: Zakaria Ismail Mahamud , Peter Appiahene , Iddrisu Wahab Abdul
Published: January 2023

BACKGROUND

Social Media, a pervasive communication medium, offers a vast opportunity for people of varied background to talk about common things of interest including public health issues.
This communication tool is crucial for the flow of information between public-health authority and the general public for the purpose of health education. The social media platform is however, inundated with voluminous unstructured data as 1.13 billion people use Facebook daily and 90 million tweets are generated on daily basis. Part of this huge data is the over 5 million Ghanaians Facebook users who create and share very large information every day.

OBJECTIVE

Thus, the purpose of this study is to discover public health related topics using Latent Dirichlet Allocation (LDA). These topics are literally hidden in huge social media data. So, we seek to meaningfully organize this shapeless Data for some insights which could optimize the operation of public health in Ghana.

METHODS

The study used Natural Language Processing to achieve the stated objective. FacePager-API was used to fetch 3,546 posts from three Facebook web pages over a six-year period. The R4.0.5 programming language was used in an experiment. Topic Modelling technique was effectively utilized in the experiment.

RESULTS

Five public-health related topics were discovered from the 3,546 posts using Latent-Dirichlet-Allocation (LDA) algorithm. The LDA model registered an accuracy level of 99%.

CONCLUSIONS

The huge generated social media data can be harnessed for the optimization of public health operations in Ghana. The study concluded that the results of the study could be useful in disease surveillance and vaccination operations. It is therefore recommended that the findings could be used to strategize how to proactively expel misinformation about a pandemic.