83 research outputs found

    Mobile information and communication technology of training

    Get PDF
    M-Learning is any sort of learning that happens when the learner is not at a fixed, predetermined location, or learning that happens when the learner takes advantage of the learning opportunities offered by mobile technologies. In other words mobile learning decreases limitation of learning location with the mobility of general portable devices. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3328

    Domination by second countable spaces and Lindelöf Σ-property

    Get PDF
    AbstractGiven a space M, a family of sets A of a space X is ordered by M if A={AK:K is a compact subset of M} and K⊂L implies AK⊂AL. We study the class M of spaces which have compact covers ordered by a second countable space. We prove that a space Cp(X) belongs to M if and only if it is a Lindelöf Σ-space. Under MA(ω1), if X is compact and (X×X)\Δ has a compact cover ordered by a Polish space then X is metrizable; here Δ={(x,x):x∈X} is the diagonal of the space X. Besides, if X is a compact space of countable tightness and X2\Δ belongs to M then X is metrizable in ZFC.We also consider the class M⁎ of spaces X which have a compact cover F ordered by a second countable space with the additional property that, for every compact set P⊂X there exists F∈F with P⊂F. It is a ZFC result that if X is a compact space and (X×X)\Δ belongs to M⁎ then X is metrizable. We also establish that, under CH, if X is compact and Cp(X) belongs to M⁎ then X is countable

    Studies on interaction of oligoadenylates with proteins in vitro by MALDI-TOF mass spectrometry

    No full text
    Aim. To investigate the ability of «core» 2'-5'- and 3'-5'-oligoadenylates (OA) to interact with α-interferon – a key protein of the 2'- 5'-OAS/RNAase L system responsible for antiviral cell defense. Methods. MALDI-TOF mass spectrometry was used in the studies on protein-ligand interactions. Results. It was shown that 2'-5'-A3 and its epoxy-modified analog 2'-5'-A3-epo can bind to α-interferon in vitro. 3'-5'-tri- adenylate is also capable of binding to this protein. One to five ligand molecules can bind simultaneously to the molecule of α-interferon. At the same time, all studied oligonucleotides do not bind to insulin. Conclusions. It was established that «core» 2'-5'- and 3'-5'-triadenylates are capable of multiple interaction with α-interferon to form stable complexes. However, they do not bind to insulin which is not involved in the 2'-5'-OAS/RNAase L system.Мета. Дослідити здатність «корових» 2'-5'- і 3'-5'-олігоаденілатів взаємодіяти з α-інтерфероном – ключовим білком системи 2'-5'-ОАС/РНКаза L, відповідальної за противірусний захист клітини. Методи. Для вивчення взаємодій білок–олігонуклеотид використано метод мас-спектрометрії MALDI-TOF. Результати. Встановлено здатність 2'-5'-А3 та його епокси-модифікованого аналога 2'-5'-А3-epo зв’язуватися з α-інтерфероном in vitro. З цим білком може також взаємодіяти і 3'-5'-триаденілат. При цьому до молекули α-інтерферону одночасно може приєднуватися від однієї до п’яти молекул ліганду. У той же час з інсуліном усі досліджені олігонуклеотиди не зв’язуються. Висновки. Показано, що «корові» 2'-5'- і 3'-5'-триаденілати множинно взаємодіють з α-інтерфероном з утворенням стійких комплексів. Однак вони не зв’язуються з інсуліном, який не є компонентом системи 2'-5'-ОАС/РНКаза L.Цель. Исследовать способность «коровых» 2'-5'- и 3'-5'-олигоаденилатов взаимодействовать с α-интерфероном – ключевым белком системы 2'-5'-ОАС/РНКаза L, ответственной за противовирусную защиту клетки. Методы. Для изучения взаимодействий белок–олигонуклеотид использован метод масс-спектрометрии MALDI-TOF. Результаты. Установлена способность 2'-5'-А3 и его эпокси-модифицированного аналога 2'-5'-А3-еpo связываться с α-интерфероном in vitro. С этим белком может также взаимодействовать и 3'-5'-триаденилат. При этом к молекуле α-интерферона одновременно может присоединяться от одной до пяти молекул лиганда. В то же время с инсулином все изученные олигонуклеотиды не связываются. Выводы. Показано, что «коровые» 2'-5'- и 3'-5'-триаденилаты способны к множественному взаимодействию с α-интерфероном с образованием устойчивых комплексов. Однако они не связываются с инсулином, не являющемся компонентом системы 2'-5'-ОАС/РНКаза L

    On the comparison of fundamental numerical ephemerides

    No full text
    We present the results of our comparison of three main numerical ephemerides (DELE, INPOP, EPM) for the determination of precision and errors of their dynamical coordinate systems. It was shown that all of them have comparable levels of precision, however the EPM demonstrates an unusual shift of the coordinate origin. Systematic errors were estimated as well, and mutual shifts of coordinate centres were found

    Модель використання мобільних інформаційно-комунікаційних технологій у навчанні інформатики майбутніх інженерів-педагогів

    Get PDF
    Research goal: the research is aimed at developing a model of use of mobile ICT in learning Computer Sciences to future professionals in Engineering Pedagogy. Object of research is the model of use of mobile ICT in learning Computer Sciences to future professionals in Engineering Pedagogy. Results of the research: the developed model of use of mobile ICT as tools of learning Computer Sciences to future professionals in Engineering Pedagogy is based on the competency-based, person-centered and systemic approaches considering principles of vocational education, general didactic principles, principles of Computer Science learning, and principles of mobile learning. It also takes into account current conditions and trends of mobile ICT development. The model comprises four blocks: the purpose-oriented block, the content-technological block, the diagnostic block and the result-oriented block. According to the model, the learning content of Computer Sciences consists of 5 main units: 1) Fundamentals of Computer Science; 2) Architecture of Modern Computers; 3) Fundamentals of Algorithmization and Programming; 4) Software of Computing Systems; 5) Computer Technologies in the Professional Activity of Engineer-pedagogues.Мета дослідження: дослідження спрямоване на розробку моделі використання мобільних ІКТ у навчанні інформатики майбутніх фахівців з інженерної педагогіки. Об'єктом дослідження є модель використання мобільних ІКТ у навчанні інформатики майбутніх фахівців з інженерної педагогіки. Результати дослідження: розроблена модель використання мобільних ІКТ як засобу навчання інформатики майбутніх фахівців з інженерної педагогіки базується на компетентнісно-орієнтованому та системнрму підходах, що враховують принципи професійної освіти, загальнодидактичні принципи, принципи навчання інформатики та принципи мобільного навчання. Вона також враховує сучасні умови та тенденції розвитку мобільних ІКТ. Модель складається з чотирьох блоків: цільовий блок, змістово-технологічний блок, діагностичний блок та результатний. Відповідно до моделі, зміст навчанні інформатики складається з 5 основних підрозділів: 1) Основи інформатики; 2) Архітектура сучасних комп'ютерів; 3) Основи алгоритмізації та програмування; 4) Програмне забезпечення обчислювальних систем; 5) Комп'ютерні технології в професійній діяльності інженерів-педагогів

    Carrier transport mechanisms in reverse biased InSb p-n junctions

    No full text
    Carrier transport mechanisms have been investigated in linearly graded InSb p-n junctions prepared using thermal diffusion of Cd into single crystal substrates of ntype conductivity. The investigations were focused on the reverse current as a function of bias voltage and temperature. The obtained experimental data show that local inhomogeneities in the depletion region are responsible for the excess tunneling current observed in the reverse biased junctions. The inhomogeneities have been attributed to dislocations, precipitates or other extended defects. A phenomenological model is proposed to explain experimental data

    Heterostructure ohmic contacts to p-CdTe polycrystalline films

    No full text
    Heterostructure contacts p⁺ -PbTe/p-CdTe were prepared using the hot-wall technique on glassceramic substrates. It has been shown that the potential barrier at the p⁺ -PbTe/p-CdTe interface is not formed in the case of heavily doped lead telluride. That allows one to create ohmic heterocontacts of metal-p⁺ -PbTe/p-CdTe type. The transverse and in-plane transport of carriers has been investigated as a function of bias voltage and temperature. The current-voltage characteristics measured for the transverse arrangement of contacts exhibited ohmic behavior. The current-voltage characteristics of these contacts are determined by unipolar injection of holes from p⁺ -PbTe into p-CdTe. The inplane transport has been explained by presence of potential barriers at the grain boundaries. The potential barrier height has been estimated to be ~0.1 eV at room temperature. The mechanism of carrier transport is thermionic emission

    Electrical properties of InSb p-n junctions prepared by diffusion methods

    No full text
    InSb p-n junctions were prepared by three diffusion methods, including isothermal, two-temperature and two-stage diffusion processes. The current-voltage characteristics were measured as a function of temperature and bias voltage. The highest values of the resistance-area product at zero bias have been obtained for the junctions prepared using the two-stage diffusion process

    Injection current and infrared photosensitivity in isotype p-PbTe/p-CdTe heterojunctions

    No full text
    Iso-type p-PbTe/p-CdTe heterojunctions were grown on BaF2 substrates by using the hot-wall epitaxy technique. The growth details are presented. The carrier transport mechanism was investigated by means of the current-voltage measurements. At 77 K the dominant conduction mechanism was found to be the space-charge-limited current. The photovoltaic response in the long-wave infrared region with the half-peak cut-off wavelength ranged from 8.0 to 9.0 m was observed in these heterojunctions for the first time. The possible mechanism of the photoresponse is the internal photoemission of holes from p-PbTe across the heterojunction barrier

    Characterization of grain boundaries in CdTe polycrystalline films

    No full text
    CdTe polycrystalline films with the average size of grains within the range 10…360 μm were grown on sapphire substrates by using the modified close-spaced sublimation technique. Transverse (across the film) and lateral (along the film’s surface) conductivity as a function of bias voltage and temperature were measured using appropriate arrangement of contacts. The transverse conductivity exhibits ohmic behavior, whereas the lateral transport of carriers is dominated by potential barriers at the grain boundaries. The carrier concentration in the grains and the potential barrier height have been estimated. The inhomogeneous distribution of deep defects through the grains was found from the photoluminescence measurements
    corecore