Literatura académica sobre el tema "STM à 4 pointes"
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Artículos de revistas sobre el tema "STM à 4 pointes"
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Geetha, K. y R. Vadivel. "Phoneme Segmentation of Tamil Speech Signals Using Spectral Transition Measure". Oriental journal of computer science and technology 10, n.º 1 (4 de marzo de 2017): 114–19. http://dx.doi.org/10.13005/ojcst/10.01.15.
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Process of identifying the end points of the acoustic units of the speech signal is called speech segmentation. Speech recognition systems can be designed using sub-word unit like phoneme. A Phoneme is the smallest unit of the language. It is context dependent and tedious to find the boundary. Automated phoneme segmentation is carried in researches using Short term Energy, Convex hull, Formant, Spectral Transition Measure(STM), Group Delay Functions, Bayesian Information Criterion, etc. In this research work, STM is used to find the phoneme boundary of Tamil speech utterances. Tamil spoken word dataset was prepared with 30 words uttered by 4 native speakers with a high quality microphone. The performance of the segmentation is analysed and results are presented.
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PAGET, D., OLIVIA PULCI, M. SAUVAGE, Y. GARREAU, LUCIA REINING, P. CHIARADIA, F. BECHSTEDT y R. PINCHAUX. "Do WE UNDERSTAND THE STRUCTURE OF THE GALLIUM-RICH SURFACE of GaAs(001)? EXPERIMENTAL AND THEORETICAL APPROACHES". Surface Review and Letters 09, n.º 03n04 (junio de 2002): 1497–510. http://dx.doi.org/10.1142/s0218625x02003858.
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While the As-rich 2 × 4 reconstruction of GaAs(001) is well explained by the so-called β2 structure, the atomic structure of the Ga-rich 4 × 2 phase has been discussed for a long time. In this review, the most important structural models for the GaAs(001) (4 × 2)/c(8 × 2) surface are compared from different theoretical and experimental points of view. The selected reconstructions include the recently proposed ζ model, a new mixed dimer model, and the well-known β, β2, Cerdà and Skala models. The different structures are compared on the basis of total energy calculations, simulations of STM experimental images and interpretation of X-ray diffraction data. Only the ζ model satisfies all criteria, and provides therefore a satisfactory explanation of the atomic structure of GaAs(001)-(4 × 2).
3
Bishop, David. "Torsades de pointes". Confederation of Australian Critical Care Nurses Journal 3, n.º 4 (diciembre de 1990): 24–30. http://dx.doi.org/10.1016/s1033-3355(11)80052-4.
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McEntee, Joseph. "Burgeoning markets for STM". Physics World 4, n.º 4 (abril de 1991): 69–70. http://dx.doi.org/10.1088/2058-7058/4/4/31.
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AVERY, A. R., D. M. HOLMES, T. S. JONES y B. A. JOYCE. "AN STM STUDY OF THE (2×4) AND c(4×4) RECONSTRUCTIONS FORMED ON GaAs(001) BY MOLECULAR BEAM EPITAXY". Surface Review and Letters 01, n.º 04 (diciembre de 1994): 621–24. http://dx.doi.org/10.1142/s0218625x94000801.
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Atomic resolution scanning tunneling microscopy (STM) has been used to study the Asterminated (2×4) and c(4×4) reconstructions formed on GaAs(001) surfaces grown in situ by molecular beam epitaxy (MBE). Filled states STM images of the (2×4) surface always showed unit cells consisting of two As dimers in the top layer. Cooling this surface under an As flux led initially to a highly kinked (2×4) phase before the transition to the c(4×4) structure. At no point were three As dimers observed in the top layer for the (2×4) unit cell. The c(4×4) structure involves the chemisorption of a second layer of As onto an already As-terminated surface. STM images of this surface showed a series of bright rectangular blocks consisting, when complete, of three pairs of As atoms.
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Jorens, Philippe G., Paul A. Van Den Heuvel y Gaston A. Parizel. "Amiodarone and torsades de pointes". American Heart Journal 120, n.º 6 (diciembre de 1990): 1482. http://dx.doi.org/10.1016/0002-8703(90)90276-4.
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HARRISON, OLIVIA L., JORDAN T. GEBHARDT, CHAD B. PAULK, BRANDON L. PLATTNER, JASON C. WOODWORTH, SUSAN RENSING, CASSANDRA K. JONES y VALENTINA TRINETTA. "Inoculation of Weaned Pigs by Feed, Water, and Airborne Transmission of Salmonella enterica Serotype 4,[5],12:i:−". Journal of Food Protection 85, n.º 4 (25 de enero de 2022): 693–700. http://dx.doi.org/10.4315/jfp-21-418.
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ABSTRACT Salmonella enterica serotype 4,[5],12:i:− (STM) has become an increasing problem for food safety and has been often detected in swine products. Weanling pigs were exposed to STM-contaminated feed, water, or air to determine possible STM transmission routes. A control group of pigs was included. STM was monitored daily in feces and rectal and nasal swabs. STM colonization was most prevalent in tissues from tonsil, lower intestine, and mesenteric lymph nodes. No differences in lesion severity were observed between inoculated and control pigs. Contaminated feed, water, and aerosolized particles caused infection in weaned pigs; however, no STM colonization was observed in skeletal muscle destined for human consumption. Based on the results from this study, STM contamination in pork products most likely results from cross-contamination of meat by digesta or lymph node tissue during processing. HIGHLIGHTS
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Robbins, David. "Silicon surface secrets revealed by STM". Physics World 4, n.º 4 (abril de 1991): 24–25. http://dx.doi.org/10.1088/2058-7058/4/4/21.
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Ortega-Carnicer, J., R. Alcázar, M. De la Torre y J. Benezet. "Pentavalent antimonial-induced torsade de pointes". Journal of Electrocardiology 30, n.º 2 (abril de 1997): 143–45. http://dx.doi.org/10.1016/s0022-0736(97)80023-4.
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Afni, Nur, Khairil Khairil y Abdullah Abdullah. "Penerapan Pendekatan STM (Sains Teknologi Masyarakat) Pada Konsep Pencemaran Lingkungan Untuk Meningkatkan Hasil Belajar Dan Kemampuan Berpikir Kritis Di Sma Negeri 4 Wira Bangsa Meulaboh". BIOTIK: Jurnal Ilmiah Biologi Teknologi dan Kependidikan 2, n.º 2 (31 de enero de 2017): 77. http://dx.doi.org/10.22373/biotik.v2i2.238.
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Telah dilaksanakan penelitian tentang “Penerapan pendekatan STM (Sains Teknologi Masyarakat) pada konsep pencemaran lingkungan untuk meningkatkan hasil belajar, kemampuan berpikir kritis, dan sikap peduli lingkungan di SMA Negeri 4 Wira Bangsa Meulabohâ€. Tujuan penelitian ini untuk mengetahui perbedaan hasil belajar, kemampuan berpikir kritis siswa pada materi pencemaran lingkungan yang dibelajarkan dengan pendekatan STM dan tanpa STM. Metode penelitian ini adalah metode eksperimental semu. Populasi dalam penelitian ini seluruh siswa kelas X SMA Negeri 4 Wira Bangsa Meulaboh, berjumlah 80 siswa yang berasal dari 3 kelas. Sampel pada penelitian ini adalah sebanyak 2 kelas yang ditentukan secara random sampling terdiri dari kelas eksperimen (dengan pendekatan STM) dan kelas kontrol (tanpa pendekatan STM). Instrumen penelitian ini menggunakan tes hasil belajar, tes kemampuan berpikir kritis. Pengujian hipotesis dilakukan dengan menggunakan uji-t Hasil pengujian hipotesis diperoleh thitung hasil belajar = 8,62, thitung kemampuan berpikir kritis = 11,15, dan thitung Karena harga thitung > ttabel maka Ha diterima dan harga thitung < ttabelmaka Ha ditolak artinya ada perbedaan peningkatan hasil belajar, kemampuan berpikir kritis siswa dengan pembelajaran STM dan tanpa pendekatan STM pada materi pencemaran lingkungan di SMA Negeri 4 Wira Bangsa Meulaboh.
Kata Kunci: Pendekatan STM, dan Pencemaran Lingkungan
A research entitled, "The application of the STM approach (Science Technology Society) on the concept of environmental pollution to improve learning outcomes, critical thinking skills, and attitudes of environmental care in SMA 4 Wira Bangsa Meulaboh " has been conducted. The purposes of this study were to find out differences in students’ learning outcomes and critical thinking skills on environmental pollution material by using STM approach. This research used quasi-experimental method. The population of this study was all of students class X of SMA Negeri 4 Wira Bangsa Meulaboh. There were 80 students from three classes. The samples were chosen randomly that consisted of two classes namely experimental class and control class. The instruments used were test for learning outcome and test for critical thinking skills. The data then analyzed by using t-test. The results of t-test for learning outcomes was 8.62, meanwhile, t-test of critical thinking skills was 11.15. Since t-count > t-table, thus Ha is accepted. If t-count < t- table then, Ha is rejected. It means there were some differences on students’ learning outcome and critical thinking skills after learning environmental pollution material by using STM approach and without using it.
Keywords: STM Approach, and Environmental Pollution
Tesis sobre el tema "STM à 4 pointes"
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Khelifi, Wijden. "Selective Growth and Characterization of InAs and InSb Nanostructures". Electronic Thesis or Diss., Université de Lille (2022-....), 2024. http://www.theses.fr/2024ULILN001.
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Les composés d'arséniure et d'antimoniure d'indium figurent parmi les candidats les plus prometteurs pour la conception de dispositifs quantiques, grâce à leurs propriétés électroniques supérieures telles que la haute mobilité des électrons et leur fort couplage spin-orbite. Cependant, leur déploiement est souvent entravé par le désaccord de maille qu'ils possèdent avec les substrats III-V conventionnels et qui les rend défectueux. Cette thèse propose une solution pour fabriquer des nanostructures d'InAs et d'InSb de bonne qualité, grâce à une croissance sélective par épitaxie par jets moléculaires dans des ouvertures de SiO2.Une étude structurale et morphologique de couches bi-dimensionnelles et de nanofils d'InAs et InSb sur des substrats de GaAs ou d'InP orientés suivant les directions [001] et [111] a été réalisée. L'optimisation des paramètres de croissance a conduit à la fabrication de nanostructures planaires continues et facettées avec une minimisation des défauts émergents. Ces systèmes ont ensuite été étudiés par microscopie à effet tunnel à quatre pointes en ultravide, technique qui permet de s'astreindre de la fabrication d'électrodes pour caractériser les propriétés de transport. La comparaison du transport dans des nanofils InAs reconstruits en surface et des nanofils cœur-coquille InAs/GaSb a révélé l'intérêt d'une encapsulation des nanofils d'InAs pour augmenter sensiblement la mobilité électronique dans les nanofils.Contrairement aux nanofils d'InAs, qui peuvent être protégés par une fine couche d'arsenic pour éviter l'oxydation de leur surface pendant leurs transferts à l'air, il n'existe pas de protection efficace pour l'InSb. Aussi, la dernière partie de la thèse porte sur la caractérisation de la désoxydation des surfaces d'InSb (001) et (111) en combinant la spectroscopie Raman et la microscopie à effet tunnel. Cette dernière étude ouvre la voie à des mesures ultérieures de transport de nanofils InSb par microscopie à effet tunnel à quatre pointes.En conclusion, la qualité structurale et électronique des nanofils d'InAs et InSb réalisée dans ce travail est compatible avec le régime de transport balistique. Ces résultats jettent les bases pour la fabrication de structures III-V plus complexes actuellement recherchées pour la conception de dispositifs quantiquesIn the landscape of electronic device fabrication, the semiconductor compounds indium arsenide (InAs) and indium antimonide (InSb) have emerged as materials of significant interest for high-speed telecommunications and infrared optoelectronics. More recently, their excellent electron transport characteristics, characterized by high mobility and strong spin-orbit coupling, render them highly conducive for applications that exploit quantum transport phenomena. However, their deployment is often hampered by the lattice mismatch they possess with conventional III-V substrates, making them defective. This thesis proposes a solution for fabricating good-quality in-plane InAs and InSb nanostructures, using selective area growth by molecular beam epitaxy in SiO2 apertures.A structural and morphological study of InAs and InSb two-dimensional layers and nanowires on GaAs and InP substrates oriented along the [001] and [111] directions has been carried out. The optimization of the growth parameters led to the fabrication of continuous and faceted planar nanostructures with minimized threading defects. These systems were then studied by four-tip scanning tunnelling microscopy in ultra-high vacuum, a technique that eliminates the need for electrode fabrication to characterize the transport properties. The comparison of transport in surface-reconstructed InAs nanowires and core-shell InAs/GaSb nanowires revealed the benefits of embedding the InAs nanowires to significantly increase the electron mobility in the nanowires.Unlike the InAs nanowires, which can be protected by a thin layer of arsenic to preventtheir surface oxidation during their transfer to air, there is no effective protection for InSb.The final part of the thesis therefore focuses on characterizing the deoxidation of InSb (001) and (111) surfaces using a combination of Raman spectroscopy and scanning tunnelling microscopy. This latter study paves the way for subsequent measurements of the transport in InSb nanowires by four-tip scanning tunnelling microscopy.In conclusion, the structural and electronic quality of the InAs and InSb nanowires produced in this work is compatible with the ballistic transport regime. These results lay down the foundations for the fabrication of the more complex III-V structures, highly prized for thedesign of quantum devices
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Sordes, Delphine. "Imagerie, manipulation et contact électronique atome par atome sur la surface Si(100) : H avec le microscope à effet tunnel basse température à 4 pointes". Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30048/document.
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La construction de circuits électroniques de section atomique est l'un des grands défis de la nanoélectronique ultime. Pour construire un circuit électronique atomique, il faut d'abord mettre au point l'instrument de construction puis choisir la surface-support stabilisant ce circuit. Sur la surface d'Au(111) préparée en ultra vide, nous avons mis en œuvre et stabilisé le tout premier LT-UHV-4 STM. Ce microscope à 4 pointes STM balayant en même temps et indépendamment une même surface a été construit pour le CEMES par la société ScientaOmicron. Sur l'Au(111), nous avons reproduit tous les résultats expérimentaux obtenus sur les meilleurs LT-UHV-STM à une pointe comme la précision en rugosité de 2 pm, les caractéristiques I-V sans moyenne sur un seul atome pendant plusieurs dizaines de minutes et la manipulation atomique suivant les modes de tiré, glissé et poussé d'un seul atome d'or sur la surface. Une fois cette optimisation réalisée, nous avons appliqué notre LT-UHV-4 STM à la surface de Si(100):H, support probable des futurs circuits atomiques électroniques. Le choix de ce support est discuté en détail avant l'enregistrement et l'analyse des images STM. Les échantillons utilisés proviennent, soit du procédé semi-industriel pleine-plaque de silicium mis au point au CEA-LETI, soit de leur préparation in situ se déroulant directement dans la chambre de préparation du LT-UHV-4 STM. Nous avons pris soin de bien interpréter les images STM de la surface Si(100):H afin par exemple de déterminer la position de chaque atome d'hydrogène. La lithographie atomique par STM a été exploitée, par pointe, sur le LT-UHV-4 STM, en mode manipulation verticale atome-par-atome et mode balayage plus rapide mais rendant l'écriture atomique moins précise. Nous avons construit nos propres fils atomiques puis des plots de contact atomiques, petits carrés de Si(100)H dépassivés de quelques nm de côté. Les courants de fuite à 2 pointes et à l'échelle atomique ont ainsi pu être mesurés sur la surface de Si(100):H entre deux de ces plots. Pour préparer les contacts atomiques à au moins 2 pointes sur un fil atomique ou sur des plots de contact nanométrique, nous avons étudié en détail les différents types de contact pointe STM-liaison pendante unique montrant la difficulté d'atteindre un quantum de conductance au contact, de par un effet de courbure de bandes. Il est donc difficile sans une mesure de force complémentaire de déterminer en partant du contact tunnel les différentes étapes du contact mécanique, électronique au contact chimique. Nos résultats ouvrent la voie à la caractérisation des circuits électroniques construits atome par atome et à l'échelle atomique à la surface d'un semi-conducteurThe construction of electronic circuits of atomic section is one of the great challenges of the ultimate nanoelectronics. To build an atomic electronic circuit, it is necessary first to develop the dedicated instrument to build up and then to choose the support surface stabilizing this circuit. On the Au(111) surface prepared in ultra-vacuum, we implemented and stabilized the very first LT-UHV-4 STM. This STM 4-probes microscopes scanning at the same time and independently the same surface was built for the CEMES by the ScientaOmicron company. On Au(111), we reproduced all the experimental results obtained on the best LT-UHV-STM with one probe such as the precision in roughness of 2 pm, the IV characteristics recording without any average on a single atom for several tens of minutes and the atomic manipulation following the pulling, sliding and pushing modes of a single gold atom on the surface. Once this optimization was carried out, we applied our LT-UHV-4 STM to the surface of Si(100):H, probable support of the future electronic atomic circuits. The choice of this medium is discussed in detail before recording and analysis of the STM images. The samples used come either from the semi-industrial full-wafer silicon process developed at CEA-LETI or from their in-situ preparation, which takes place directly in the preparation chamber of the LT-UHV-4 STM. We have taken care to interpret the STM images of the surface Si(100):H in order to locate the position of each hydrogen atom. The atomic lithography by STM has been exploited, by using one tip from our LT-UHV-4 STM, by atom-per-atom vertical mode and faster scanning mode. The last makes atomic writing less accurate. We have constructed our own atomic wires and then atomic contact pads, small squares of Si(100)H defeated by a few nm sides. The leakage currents with 2 probes at the atomic scale have thus been able to be measured on the surface of Si(100):H between two of these pads. To prepare the atomic contacts at least 2 probes on an atomic wire or on nanometric contact pads, we studied in detail the different types of contact points STM-single dangling bond showing the difficulty of reaching a quantum of conductance at contact, due to a possible bands bending. It is therefore difficult without a complementary force measurement to determine, starting from the tunnel contact, the different steps of the mechanical, electronic contact at the chemical contact. Our results open the way to the characterization of electronic circuits constructed atom-by-atom and at atomic scale on the surface of a semiconductor
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Zieschang, Michael. "PCI-Einsteckkarte für ATM-Netzwerkanalyse". Master's thesis, Universitätsbibliothek Chemnitz, 2002. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-200200614.
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Development of a PCI card for PCI bus based host systems, which allows for analysis of ATM data streams on ATM transmission links with a data rate of 622Mbit/s. Implementation and previous deliberations and therefrom and from given specifications arisen partial tasks Fields of application of the ATM-Analyzer board Depiction of particular development steps Functional description of the ATM-Analyzer Explanations on how to put the PCB and the employed test software into operation Assessment of test resultsEntwicklung einer Einsteckkarte für PCI-Bus-basierte Hostsysteme zur Analyse von Datenströmen auf ATM-Übertragungsstrecken mit einer Geschwindigkeit von 622 Mbit/s. Realisierung und damit verbundene Vorüberlegungen und daraus und aus gegebenen Spezifikationen erwachsene Teilaufgaben Anwendungsgebiete der Analyzer-Karte Darstellung der einzelnen Entwicklungsschritte Funktionsbeschreibung des ATM-Analyzers Erläuterungen zur Inbetriebnahme der Leiterkarte und der verwendeten Testsoftware Bewertung der Testergebnisse
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Hohmeister, Holger. "Darstellung neuer Organometallhalogenide mit Elementen der 13. und 14. Gruppe des Periodensystems und Versuche zur Synthese von Organogermanolen". Doctoral thesis, [S.l.] : [s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=969563310.
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Lin, Shang-Shu y 林上書. "A UHV-STM/STS Study of Electronic Structures of[Ni3(dpa)4(NCS)2] and [Ni11(bnatpya)4(NCS)2](PF6)4". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/6j9a9m.
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碩士國立臺灣大學
化學研究所
105
This study discuss the arrangement and electricity of two one-dimensional metal string molecules [Ni3(dpa)4(NCS)2] and [Ni11(bnatpya)4(NCS)2]4+ which are different lengths on the Au(111) surface. Sample preparation and surface analysis were obtained by ultrahigh vacuum scanning tunneling microscope (UHV-STM). The samples were prepared by dissolving the metal string molecular with the CH2Cl2 solvent, then drop on the surface of Au(111) and obtaining the [Ni3(dpa)4(NCS)2]/Au(111) and [Ni11(bnatpya)4(NCS)2]4+/Au(111). In the first part, the STM image shows that [Ni3(dpa)4(NCS)2] is adsorbed on the step edge of Au(111) surface, and the height of single metal string molecule could obtained from the height profile. The dI/dV spectra of [Ni3(dpa)4(NCS)2] on Au(111) revealed two characteristic peaks, −0.65 eV and −0.10 eV by the scanning tunneling spectroscopy (STS) .To make sure the molecular characteristics from the image, using the longer molecules of [Ni11(bnatpya)4(NCS)2]4+ to drop on the surface, and the STM image shows the molecules are disorderly and distributed on the surface with one or more repeating monomers by the coffee ring effect. The dI/dV spectrum on the cluster and the single molecule, respectively, the results show that the cluster has a broad peak at the negative bias. In the second part, the chamber is cooled to 78 K to reduce the influence of the thermal disturbance of the molecule and the tip. From the STM images, the electron cloud of single metal string molecule exhibits a left-handed and right-handed configuration with an angle of about 50o between the metal axis and the helical electron cloud. In addition, it is observed that the electron cloud of some molecules reveal non-left and right hand but rather about 90o with the metal axis.
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Kumar, Vimal. "Design of Audio Player and Recorder on STM 32F4 Discovery Board". Thesis, 2015. http://ethesis.nitrkl.ac.in/7689/1/2015_Design_Kumar_(4).pdf.
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With the advancement in semiconductor technology, scope for development of embedded systems has increased manifolds. New processors with improved computing capabilities and low power consumption have further accelerated the developments in embedded domain. Consumers are looking for affordable multimedia devices with high performance and durability making embedded developers to think creatively and use all resources at hand to meet the desired user specifications. This is one such attempt by designing an Audio Player and Recorder to play the wave audio files from a USB flash drive and recording the audio in USB flash drive in the same format. In this application MEMS microphone is used for recording the audio data
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Cheng, Ming-Chi y 鄭名期. "A UHV-STM/STS Study of Electronic Structures and Electron Transports of [Ni11(bnatpya)4(NCS)2](PF6)4". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/f7h8s7.
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碩士國立臺灣大學
化學研究所
107
This thesis presents the molecular structures and the single-molecular conductivity of a long-chain-shaped polynuclear metal string complex [Ni11(bnatpya)4(NCS)2]4+ (Ni11) on the single crystal surface of Au(111) by ultrahigh-vacuum scanning tunneling microscopy (UHV-STM). The Au(111) surface was prepared by annealing to generate the reconstruction. Ni11 was dissolved in methanol and deposited on Au(111). At 78 K UHV-STM, the STM images showed oblate-shaped structures of Ni11 on Au(111). From the height profiles, single-molecular size of Ni11 could be obtained from the images of topography. Scanning tunneling spectroscopy (STS) indicated density of states (DOS) of Ni11 by dI/dV spectra exhibiting the distributions of peaks at -1.20 eV and +0.82 eV, excluding the shifting peak of gold surface state. Compared with ultraviolet-visible spectroscopy, the energy difference acquired from dI/dV spectra could be identified with aligned energy of HOMO-LUMO gap. The STM probe was able to contact the ending thiocyanate group of Ni11, which would contribute to the single-molecular circuit while the Ni11 molecules were lifted from the surface. Conductance-to-distance graph was measured in the process of lifting to calculate the single-molecular conductance. The measured conductance at 78 K was slightly higher than the previous results at room temperature. Despite the discrepancy from heat-dependent mechanism of electron tunneling, this is an important reference to further discuss on molecular conductance if considering the effects of setpoint bias as well as coupling interactions between ending thiocyanate group and the electrodes.
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Fang, yuan. "Synthesis and Self-Assembly of Quinoidal Molecules at the Liquid-Solid Interface – An STM Investigation". Thesis, 2013. http://spectrum.library.concordia.ca/977870/4/Fang_MSc_F2013.pdf.
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An exploration of the 2D supramolecular self-assembly of benzoquinone derivatives at the liquid-solid interface using scanning tunneling microscopy (STM) is presented. In the 30 years since its discovery, STM has emerged as one of the most powerful and unique surface characterization techniques. We have applied a versatile transamination reaction of 2,4-diaminoresorcinol to synthesize zwitterionic meta-diaminobenzoquinones (Cnm) with the ability to form robust charge-assisted hydrogen bonded arrays. Charge-assisted hydrogen bonding, where traditional hydrogen bonding is accompanied by Coulombic interactions, leads to exceptionally strong and inherently flexible interactions between oppositely charged or zwitterionic components. The typical energy of a NH···O charge-assisted hydrogen bond is 4 times as strong as that of normal hydrogen bond. We also have easy access to para-aminobenzoquinones (Cnp) which have the ability to form a conventional hydrogen-bond network. Formation and self-assembly of the 2:1 metal complex of C18m with Ni(II), (C18m)2Ni, was investigated and conglomerate chiral domains were observed in contrast to the pseudoracemic domains of C18m. In this thesis, synthesis of the above mentioned compounds under both solvent and solvent-free conditions are described. In addition, factors governing morphology, chirality and multilayer formation are discussed, presenting an important foundation for understanding the properties of a large family of related molecules with interesting potential in supramolecular design. Controlling well-defined 2D structures provides important insight into crystallization and is an essential step in the rational design of solid-state materials for interfacial applications.
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Zieschang, Michael. "PCI-Einsteckkarte für ATM-Netzwerkanalyse". Master's thesis, 2001. https://monarch.qucosa.de/id/qucosa%3A17839.
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Development of a PCI card for PCI bus based host systems, which allows for analysis of ATM data streams on ATM transmission links with a data rate of 622Mbit/s.
Implementation and previous deliberations and therefrom and from given specifications arisen partial tasks
Fields of application of the ATM-Analyzer board
Depiction of particular development steps
Functional description of the ATM-Analyzer
Explanations on how to put the PCB and the employed test software into operation
Assessment of test resultsEntwicklung einer Einsteckkarte für PCI-Bus-basierte Hostsysteme zur Analyse von Datenströmen auf ATM-Übertragungsstrecken mit einer Geschwindigkeit von 622 Mbit/s. Realisierung und damit verbundene Vorüberlegungen und daraus und aus gegebenen Spezifikationen erwachsene Teilaufgaben Anwendungsgebiete der Analyzer-Karte Darstellung der einzelnen Entwicklungsschritte Funktionsbeschreibung des ATM-Analyzers Erläuterungen zur Inbetriebnahme der Leiterkarte und der verwendeten Testsoftware Bewertung der Testergebnisse
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Janssen, Jörg. "Synthese löslicher Aggregate des Indiums und Zinns". Doctoral thesis, 2003. http://hdl.handle.net/11858/00-1735-0000-0006-B074-4.
Texto completoLibros sobre el tema "STM à 4 pointes"
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Samorì, Paolo, ed. STM and AFM Studies on (Bio)molecular Systems: Unravelling the Nanoworld. Berlin, Heidelberg: Springer Berlin Heidelberg, 2008. http://dx.doi.org/10.1007/978-3-540-78395-4.
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Kramer, Rutger. Rethinking Authority in the Carolingian Empire. NL Amsterdam: Amsterdam University Press, 2019. http://dx.doi.org/10.5117/9789462982642.
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By the early ninth century, the responsibility for a series of social, religious and political transformations had become an integral part of running the Carolingian empire. This became especially clear when, in 813/4, Louis the Pious and his court seized the momentum generated by their predecessors and broadened the scope of these reforms ever further. These reformers knew they represented a movement greater than the sum of its parts; the interdependence between those wielding imperial authority and those bearing responsibility for ecclesiastical reforms was driven by comprehensive, yet still surprisingly diverse expectations. Taking this diversity as a starting point, this book takes a fresh look at the optimistic first decades of the ninth century. Extrapolating from a series of detailed case studies rather than presenting a new grand narrative, it offers new interpretations of contemporary theories of personal improvement and institutional correctio, and shows the self-awareness of its main instigators as they pondered what it meant to be a good Christian in a good Christian empire.
Capítulos de libros sobre el tema "STM à 4 pointes"
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Matsuda, Azusa, Satoshi Sugita y Takao Watanabe. "Pseudogap Probed by STM". En Advances in Superconductivity XI, 151–56. Tokyo: Springer Japan, 1999. http://dx.doi.org/10.1007/978-4-431-66874-9_30.
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Murakami, Hironaru, Toshiyuki Kita y Ryozo Aoki. "LT-STM/STS Study on Bi2Sr2CaCu2Oy". En Advances in Superconductivity VII, 57–60. Tokyo: Springer Japan, 1995. http://dx.doi.org/10.1007/978-4-431-68535-7_11.
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Majima, Yutaka. "STM Characterization of π-Electron Systems". En Chemical Science of π-Electron Systems, 621–34. Tokyo: Springer Japan, 2015. http://dx.doi.org/10.1007/978-4-431-55357-1_37.
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Renner, Christophe y Øystein Fischer. "Tunneling Spectroscopy and STM Observation of Flux Lines". En Advances in Superconductivity VI, 429–34. Tokyo: Springer Japan, 1994. http://dx.doi.org/10.1007/978-4-431-68266-0_92.
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Kashiwaya, Satoshi, Masao Koyanagi, Hiroshi Takashima, Mizushi Matsuda y Koji Kajimura. "Magnetic Responses of Zero-bias Conductance Peaks by LT-STM". En Advances in Superconductivity VI, 73–76. Tokyo: Springer Japan, 1994. http://dx.doi.org/10.1007/978-4-431-68266-0_13.
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Chao, Congping y Satoaki Arai. "STM Inestigations of the Grain Surface of Bi0.8PbxSr1Ca1Cu1.6O8+y Superconductors". En Advances in Superconductivity II, 529–32. Tokyo: Springer Japan, 1990. http://dx.doi.org/10.1007/978-4-431-68117-5_114.
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Kumagai, Takashi. "Hydroxyl Dimer: Non-linear I–V Characteristics in an STM Junction". En Visualization of Hydrogen-Bond Dynamics, 91–100. Tokyo: Springer Japan, 2012. http://dx.doi.org/10.1007/978-4-431-54156-1_8.
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Ikeda, Kazuto, Kenshi Takamuku, Koji Yamaguchi, Rittaporn Itti, Naoki Koshizuka y Shoji Tanaka. "STM Observation on Bi-O Surfaces of Bi2Sr2Ca1-xYxCu2Oy Single-Crystals". En Advances in Superconductivity IV, 299–301. Tokyo: Springer Japan, 1992. http://dx.doi.org/10.1007/978-4-431-68195-3_62.
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Ting, Wu, M. Badaye, R. Itti, K. Ishimaru, T. Morishita, N. Koshizuka y S. Tanaka. "Low temperature STM/STS measurements on c-axis oriented Y1Ba2Cu4O8 superconductive films". En Advances in Superconductivity VII, 49–52. Tokyo: Springer Japan, 1995. http://dx.doi.org/10.1007/978-4-431-68535-7_9.
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Renner, Christophe, Bernard Revaz, Kazuo Kadowaki, Ivan Maggio-Aprile, Andreas Erb, Eric Walker y Øystein Fischer. "STM Vortex Core Spectroscopy and Non-BCS Pairing in High Temperature Superconductors". En Advances in Superconductivity XI, 145–50. Tokyo: Springer Japan, 1999. http://dx.doi.org/10.1007/978-4-431-66874-9_29.
Texto completoActas de conferencias sobre el tema "STM à 4 pointes"
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Takada, Kan, Misaichi Takeuchi y Takuji Takahashi. "Light-Illuminated STM Studies on InAs Nano-Structures". En 2001 International Conference on Solid State Devices and Materials. The Japan Society of Applied Physics, 2001. http://dx.doi.org/10.7567/ssdm.2001.d-6-4.
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Lewis, P. A., B. W. Alphenaar y H. Ahmed. "UHV-STM Study of Electron Emission from Individual Silicon Nanopillars". En 2000 International Conference on Solid State Devices and Materials. The Japan Society of Applied Physics, 2000. http://dx.doi.org/10.7567/ssdm.2000.d-5-4.
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FUKANO, Yoshinobu, Yasuhiro SUGAWARA, Seizo MORITA, Yoshiki YAMANISHI y Takahiko OASA. "Nanometer Resolution Measurement of Dielectric Breakdown of Silicon Dioxide Films with AFM/STM". En 1992 International Conference on Solid State Devices and Materials. The Japan Society of Applied Physics, 1992. http://dx.doi.org/10.7567/ssdm.1992.pa1-4.
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ONO, Yukinori y Michiharu TABE. "STM Study of Thermal Oxidation Process on Si(111) 7×7 Surfaces". En 1992 International Conference on Solid State Devices and Materials. The Japan Society of Applied Physics, 1992. http://dx.doi.org/10.7567/ssdm.1992.s-v-4.
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Müller, M., N. Martín Sabanés, F. Schulz, F. Krecinic, T. Kumagai, T. Kampfrath y M. Wolf. "Quantitative sampling of femtosecond THz voltage pulses and hot electron dynamics in an STM junction". En CLEO: QELS_Fundamental Science. Washington, D.C.: OSA, 2021. http://dx.doi.org/10.1364/cleo_qels.2021.fth4l.4.
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MATSUMOTO, KAZUHIKO, Shu Takahashi, Masami Ishii, Masakatsu Hoshi, Akira Kurokawa, Shingo Ichimura y Atsushi Ando. "First Application of STM Nano-Meter Size Oxidation Process to Planar-Type MIM Diode". En 1994 International Conference on Solid State Devices and Materials. The Japan Society of Applied Physics, 1994. http://dx.doi.org/10.7567/ssdm.1994.s-i-4-2.
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Xie, X. Sunney y Robert C. Dunn. "Fluorescence Spectroscopy on a Single Molecule Basis with a Near-field Spectrometer". En Laser Applications to Chemical Analysis. Washington, D.C.: Optica Publishing Group, 1994. http://dx.doi.org/10.1364/laca.1994.thd.4.
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Recent advances in near-field optical microscopy [1] have offered exciting possibilities for conducting molecular spectroscopy at the nanometer dimension. In particular, fluorescence detection of single chromophores and single proteins containing several chromophores have been achieved using this technique[2][3]. For chemical analysis and biological applications, fluorescence measurements with near-field optics will be particularly informative, providing spectroscopic information not accessible with other scanning probe techniques, such as SEM, STM and AFM.
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Altfeder, I. B., D. M. Chen y K. A. Matveev. "Electron Interference Fringes on a Pb Quantum Wedge". En Chemistry and Physics of Small-Scale Structures. Washington, D.C.: Optica Publishing Group, 1997. http://dx.doi.org/10.1364/cps.1997.ctub.1.
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Optical Fizeau fringes appear when a monochromatic light illuminates the surface of a thin optically transparent wedge. As the wavelength of the Fermi electrons in a metal is by a factor of 1000 smaller then the wavelength of light, one could expect to observe the similar phenomenon of electron interference fringes on a nanometer thickness metal wedge. The perfect tool to detect the electron interference pattern is a scanning tunneling microscope (STM), as it can probe the local density of states (LDOS), and test the interference conditions for the Fermi electrons. Indeed, the STM has been used successfully to reveal different surface interference phenomena (1-4).
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Zhou, Y., K. S. Yew y D. S. Ang. "A Possible Bipolar HfOx Resistive Memory Device with Self-Rectification - Observations from STM Study". En 2014 International Conference on Solid State Devices and Materials. The Japan Society of Applied Physics, 2014. http://dx.doi.org/10.7567/ssdm.2014.ps-4-2.
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Zhang, Li, James A. Bain, Jian-Gang Zhu, Leon Abelmann y Takahiro Onoue. "The Role of STM Tip Shape in Heat Assisted Magnetic Probe Recording on CONI/PT Film". En ASME 2004 3rd Integrated Nanosystems Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/nano2004-46057.
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A method of heat-assisted magnetic recording (HAMR) potentially suitable for probe-based storage systems is characterized. In this work, field emission current from a scanning tunneling microscope (STM) tip is used as the heating source. The tip is made of Ir/Pt alloy. Pulse voltages of 3–7 V with a duration of 500 ns were applied to a CoNi/Pt multilayered film. Written by a blunt tip (radius 1000 nm), marks are formed with a nearly uniform mark size of 170 nm when the pulse voltage is above 4 V. While sharp tip (radius 50 nm) writing achieves no mark. The emission area of our tip-sample system derived from an analytic expression for field emission current is approximately equal to the mark size, and is largely independent of pulse voltage. For the blunt tip, the emission region is almost the same as the mark size. While for the sharp tip, the initially formed mark is too small, so that the domain wall surface tension shrinks the mark and it crashes finally.
Informes sobre el tema "STM à 4 pointes"
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Schat, Karel Antoni, Irit Davidson y Dan Heller. Chicken infectious anemia virus: immunosuppression, transmission and impact on other diseases. United States Department of Agriculture, 2008. http://dx.doi.org/10.32747/2008.7695591.bard.
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1. Original Objectives. The original broad objectives of the grant were to determine A) the impact of CAV on the generation of cytotoxic T lymphocytes (CTL) to reticuloendotheliosis virus (REV) (CU), B). the interactions between chicken anemia virus (CAV) and Marek’s disease virus (MDV) with an emphasis on horizontal spread of CAV through feathers (KVI), and C) the impact of CAV infection on Salmonella typhimurium (STM) (HUJI). During the third year and the one year no cost extension the CU group included some work on the development of an antigen-antibody complex vaccine for CAV, which was partially funded by the US Poultry and Egg Association. 2. Background to the topic. CAV is a major pathogen causing clinical disease if maternal antibody-free chickens are infected vertically or horizontally between 1 and 14 days of age. Infection after 3 weeks of age when maternal antibodies are not longer present can cause severe subclinical immunosuppression affecting CTL and cytokine expression. The subclinical immunosuppression can aggravate many diseases including Marek’s disease (MD) and several bacterial infections. 3. Major conclusions and achievements. The overall project contributed in the following ways to the knowledge about CAV infection in poultry. As expected CAV infections occur frequently in Israel causing problems to the industry. To control subclinical infections vaccination may be needed and our work indicates that the development of an antigen-antibody complex vaccine is feasible. It was previously known that CAV can spread vertically and horizontally, but the exact routes of the latter had not been confirmed. Our results clearly show that CAV can be shed into the environment through feathers. A potential interaction between CAV and MD virus (MDV) in the feathers was noted which may interfere with MDV replication. It was also learned that inoculation of 7-day-old embryos causes growth retardation and lesions. The potential of CAV to cause immunosuppression was further examined using CTL responses to REV. CTL were obtained from chickens between 36 and 44 days of age with REV and CAV given at different time points. In contrast to our earlier studies, in these experiments we were unable to detect a direct impact of CAV on REV-specific CTL, perhaps because the CTL were obtained from older birds. Inoculation of CAV at one day of age decreased the IgG antibody responses to inactivated STM administered at 10 days of age. 4. Scientific and Agricultural Implications The impact of the research was especially important for the poultry industry in Israel. The producers have been educated on the importance of the disease through the many presentations. It is now well known to the stakeholders that CAV can aggravate other diseases, decrease productivity and profitability. As a consequence they monitor the antibody status of the breeders so that the maternal antibody status of the broilers is known. Also vaccination of breeder flock that remain antibody negative may become feasible further reducing the negative impact of CAV infection. Vaccination may become more important because improved biosecurity of the breeder flocks to prevent avian influenza and Salmonella may delay the onset of seroconversion for CAV by natural exposure resulting in CAV susceptible broilers lacking maternal antibodies. Scientifically, the research added important information on the horizontal spread of CAV through feathers, the interactions with Salmonella typhimurium and the demonstration that antigen-antibody complex vaccines may provide protective immunity.
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Lang, Jonas. Multilevel Modeling in R: Basic and Advanced Methods + 1 Free Seminar. Instats Inc., 2022. http://dx.doi.org/10.61700/sw0snl2upp0gv469.
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The hands-on seminar teaches basic and intermediate multilevel techniques used in the social, health, and organizational sciences in an accessible manner. The course relies on the free software R and the modeling packages lme4 and nlme along with help functions and datasets from the multilevel library (Bliese, 2021). Topics include (1) aggregation models and the use of agreement and reliability statistics like the ICC1, ICC2, and rwg, (2) model specification and interpretation of “standard” multilevel models used in organizational research (data centering, random slopes, interaction effects), (3) graphical methods to examine model assumptions, and (4) useful extensions of the standard model to test phenomena such as cross-classified multilevel models and consensus emergence in groups. When purchasing the seminar you will be freely enrolled in an on-demand seminar on multilevel SEM in R by Professor Zyphur, helping you to extend your multilevel learning and offering a substantial value. An official Instats certificate of completion is provided at the conclusion of the seminar. For European PhD students, each seminar offers 2 ECTS Equivalent points.
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Sela, Shlomo y Michael McClelland. Investigation of a new mechanism of desiccation-stress tolerance in Salmonella. United States Department of Agriculture, enero de 2013. http://dx.doi.org/10.32747/2013.7598155.bard.
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Low-moisture foods (LMF) are increasingly involved in foodborne illness. While bacteria cannot grow in LMF due to the low water content, pathogens such as Salmonella can still survive in dry foods and pose health risks to consumer. We recently found that Salmonella secretes a proteinaceous compound during desiccation, which we identified as OsmY, an osmotic stress response protein of 177 amino acids. To elucidate the role of OsmY in conferring tolerance against desiccation and other stresses in Salmonella entericaserovarTyphimurium (STm), our specific objectives were: (1) Characterize the involvement of OsmY in desiccation tolerance; (2) Perform structure-function analysis of OsmY; (3) Study OsmY expression under various growth- and environmental conditions of relevance to agriculture; (4) Examine the involvement of OsmY in response to other stresses of relevance to agriculture; and (5) Elucidate regulatory pathways involved in controlling osmY expression. We demonstrated that an osmY-mutant strain is impaired in both desiccation tolerance (DT) and in long-term persistence during cold storage (LTP). Genetic complementation and addition of a recombinantOsmY (rOsmY) restored the mutant survival back to that of the wild type (wt). To analyze the function of specific domains we have generated a recombinantOsmY (rOsmY) protein. A dose-response DT study showed that rOsmY has the highest protection at a concentration of 0.5 nM. This effect was protein- specific as a comparable amount of bovine serum albumin, an unrelated protein, had a three-time lower protection level. Further characterization of OsmY revealed that the protein has a surfactant activity and is involved in swarming motility. OsmY was shown to facilitate biofilm formation during dehydration but not during bacterial growth under optimal growth conditions. This finding suggests that expression and secretion of OsmY under stress conditions was potentially associated with facilitating biofilm production. OsmY contains two conserved BON domains. To better understand the role of the BON sites in OsmY-mediated dehydration tolerance, we have generated two additional rOsmY constructs, lacking either BON1 or BON2 sites. BON1-minus (but not BON2) protein has decreased dehydration tolerance compared to intact rOsmY, suggesting that BON1 is required for maximal OsmY-mediated activity. Addition of BON1-peptide at concentration below 0.4 µM did not affect STm survival. Interestingly, a toxic effect of BON1 peptide was observed in concentration as low as 0.4 µM. Higher concentrations resulted in complete abrogation of the rOsmY effect, supporting the notion that BON-mediated interaction is essential for rOsmY activity. We performed extensive analysis of RNA expression of STm undergoing desiccation after exponential and stationary growth, identifying all categories of genes that are differentially expressed during this process. We also performed massively in-parallel screening of all genes in which mutation caused changes in fitness during drying, identifying over 400 such genes, which are now undergoing confirmation. As expected OsmY is one of these genes. In conclusion, this is the first study to identify that OsmY protein secreted during dehydration contributes to desiccation tolerance in Salmonella by facilitating dehydration- mediated biofilm formation. Expression of OsmY also enhances swarming motility, apparently through its surfactant activity. The BON1 domain is required for full OsmY activity, demonstrating a potential intervention to reduce pathogen survival in food processing. Expression and fitness screens have begun to elucidate the processes of desiccation, with the potential to uncover additional specific targets for efforts to mitigate pathogen survival in desiccation.
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Oza, Shardul y Jacobus Cilliers. What Did Children Do During School Closures? Insights from a Parent Survey in Tanzania. Research on Improving Systems of Education (RISE), mayo de 2021. http://dx.doi.org/10.35489/bsg-rise-ri_2021/027.
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In this Insight Note, we report results of a phone survey that the RISE Tanzania Research team conducted with 2,240 parents (or alternate primary care-givers) of primary school children following the school closures in Tanzania. After the first case of COVID-19 was confirmed in Tanzania on 16 March 2020, the government ordered all primary schools closed the following day. Schools remained closed until 29 June 2020. Policymakers and other education stakeholders were concerned that the closures would lead to significant learning loss if children did not receive educational support or engagement at home. To help stem learning loss, the government promoted radio, TV, and internet-based learning content to parents of school-age children. The primary aims of the survey were to understand how children and families responded to the school closures, the education related activities they engaged in, and their strategies to send children back to school. The survey also measures households’ engagement with remote learning content over the period of school closures. We supplement the findings of the parent survey with insights from interviews with Ward Education Officers about their activities during the school closures. The survey sample is comprised of primary care-givers (in most cases, parents) of students enrolled in Grades 3 and 4 during the 2020 school year. The survey builds on an existing panel of students assessed in 2019 and 2020 in a nationally representative sample of schools.4 The parent surveys were conducted using Computer Assisted Telephonic Interviewing (CATI) over a two-week period in early September 2020, roughly two months after the re-opening of primary schools. We report the following key findings from this survey: *Almost all (more than 99 percent) of children in our sample were back in school two months after schools re-opened. The vast majority of parents believed it was either safe or extremely safe for their children to return to school. *Only 6 percent of households reported that their children listened to radio lessons during the school closures; and a similar fraction (5.5 percent) tuned into TV lessons over the same period. Less than 1 percent of those surveyed accessed educational programmes on the internet. Households with access to radio or TV reported higher usage. *Approximately 1 in 3 (36 percent) children worked on the family farm during the closures, with most children working either 2 or 3 days a week. Male children were 6.2 percentage points likelier to work on the family farm than female children. *Households have limited access to education materials for their child. While more than 9 out of 10 households have an exercise book, far fewer had access to textbooks (35 percent) or own reading books (31 percent). *One in four parents (24 percent) read a book to their child in the last week.
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Gruson-Daniel, Célya y Maya Anderson-González. Étude exploratoire sur la « recherche sur la recherche » : acteurs et approches. Ministère de l'enseignement supérieur et de la recherche, noviembre de 2021. http://dx.doi.org/10.52949/24.
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• Introduction Dans le cadre du deuxième Plan National de la Science Ouverte, le Comité pour la science ouverte a souhaité mener une étude pour la préfiguration d’un Lab de la science ouverte (LabSO) afin de mieux comprendre le périmètre de la recherche sur la recherche (research on research) dans un contexte international. • Objectifs de l’étude : L’étude répond ainsi à trois objectifs : 1. repérer des grands courants de recherche sur la recherche (RoR) dans le paysage plus général de la recherche universitaire en Europe et outre-atlantique, en reconnaître les principaux acteurs institutionnels et différencier les approches mobilisées par les uns et les autres ; 2. proposer une méthodologie d’analyse dans une démarche de science ouverte (méthodes mixtes et cartographie numérique) pour faciliter l’appropriation de son contenu ; 3. émettre des recommandations pour faciliter le positionnement du LabSO et s’inspirer d’initiatives existantes. • Méthodologie Une série de treize entretiens et une collecte de données d’une sélection thématique de sites web ont permis de dresser un paysage d’acteurs et d’approches impliqués dans des recherches sur la recherche. Ce dernier s’est nourri d’une démarche de cartographie numérique pour repérer et visualiser les liens existants entre différentes communautés, mouvements, réseaux et initiatives (financeurs, projets, centres de recherche, fournisseurs de données, éditeurs, etc.). • Résultats Le rapport présente différents courants de « recherche sur la recherche » issus des traditions théoriques et méthodologiques de la sociologie, de l’économie, des sciences politiques, de la philosophie, des sciences de l’information et des mesures (biblio/scientométrie). Des courants plus récents sont aussi décrits. Ils s’inscrivent dans un contexte de politiques publiques favorables à la science ouverte et ont émergé dans le champ des sciences sociales computationnelles, des Big Data ou encore des domaines biomédicaux. Si certaines de ces approches s’appuient sur des courants académiques (STS, sciences des mesures) établis depuis de nombreuses décennies, d’autres comme ceux de la « métascience » ou de la « science de la science », se sont structurées plus récemment avec une visée prescriptive et de changement fondé sur des preuves (evidence-based) se basant sur un engagement normatif pour une science plus ouverte, inclusive et diverse. Bien loin d’un paysage statique, l’étude fait ressortir des recherches en mouvement, des débats tout autant que des mises en garde afin que certains courants « ne réinventent pas la roue » en faisant fit d’une longue tradition académique de l’étude des sciences et de la production scientifiques. De nouvelles alliances entre centres de recherche et laboratoires, institutions subventionnaires, décideurs politiques et fournisseurs de données ont été repérées. Elles participent à une dynamique actuelle d’équipement des politiques publiques par des outils d’évaluation et des protocoles de recherche pour guider les actions menées, on parle d’évidence-based policies. Un des exemples les plus récents étant laa seconde feuille de route du RoRI1 poussant notamment à la formation d’un réseau international d’instituts de recherche sur la recherche, fondé sur le partage et la mutualisation de données, de méthodes et d’outils. Outre la présentation de ces différents acteurs et courants, le rapport pointe le rôle joué par les infrastructures et les fournisseurs de données scientifiques (publications, données, métadonnées, citations, etc.) dans la structuration de ce paysage et les équilibres à trouver. • Recommandations 1. Accompagner la construction d’indicateurs et de métriques par le biais d’un regard critique et de discussions collectives pour mesurer leurs impacts sur les comportements des professionnels de la recherche (mésusages, gaming). 2. Porter attention aux étapes de diffusion des résultats scientifiques issus des « recherches sur la recherche » pour les adapter aux différents publics ciblés (chercheurs, responsables des politiques publiques de recherche, journalistes, etc.). 3. Articuler les travaux de « recherche sur la recherche » avec une démarche de science ouverte en questionnant notamment les choix faits concernant les fournisseurs de données, les infrastructures et outils d’évaluation, de découvrabilité et d’analyse de la production scientifique (gouvernance, utilisation des données, etc.). 4. Soutenir les approches thématiques et transversales plutôt que disciplinaire de manière collaborative entre les différents membres du Lab de la science ouverte et aider le dialogue entre les différentes approches et mouvements (STS, research on research, science of science, scientométrie, etc.)
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Eshed-Williams, Leor y Daniel Zilberman. Genetic and cellular networks regulating cell fate at the shoot apical meristem. United States Department of Agriculture, enero de 2014. http://dx.doi.org/10.32747/2014.7699862.bard.
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The shoot apical meristem establishes plant architecture by continuously producing new lateral organs such as leaves, axillary meristems and flowers throughout the plant life cycle. This unique capacity is achieved by a group of self-renewing pluripotent stem cells that give rise to founder cells, which can differentiate into multiple cell and tissue types in response to environmental and developmental cues. Cell fate specification at the shoot apical meristem is programmed primarily by transcription factors acting in a complex gene regulatory network. In this project we proposed to provide significant understanding of meristem maintenance and cell fate specification by studying four transcription factors acting at the meristem. Our original aim was to identify the direct target genes of WUS, STM, KNAT6 and CNA transcription factor in a genome wide scale and the manner by which they regulate their targets. Our goal was to integrate this data into a regulatory model of cell fate specification in the SAM and to identify key genes within the model for further study. We have generated transgenic plants carrying the four TF with two different tags and preformed chromatin Immunoprecipitation (ChIP) assay to identify the TF direct target genes. Due to unforeseen obstacles we have been delayed in achieving this aim but hope to accomplish it soon. Using the GR inducible system, genetic approach and transcriptome analysis [mRNA-seq] we provided a new look at meristem activity and its regulation of morphogenesis and phyllotaxy and propose a coherent framework for the role of many factors acting in meristem development and maintenance. We provided evidence for 3 different mechanisms for the regulation of WUS expression, DNA methylation, a second receptor pathway - the ERECTA receptor and the CNA TF that negatively regulates WUS expression in its own domain, the Organizing Center. We found that once the WUS expression level surpasses a certain threshold it alters cell identity at the periphery of the inflorescence meristem from floral meristem to carpel fate [FM]. When WUS expression highly elevated in the FM, the meristem turn into indeterminate. We showed that WUS activate cytokinine, inhibit auxin response and represses the genes required for root identity fate and that gradual increase in WUCHEL activity leads to gradual meristem enlargement that affect phyllotaxis. We also propose a model in which the direction of WUS domain expansion laterally or upward affects meristem structure differently. We preformed mRNA-seq on meristems with different size and structure followed by k-means clustering and identified groups of genes that are expressed in specific domains at the meristem. We will integrate this data with the ChIP-seq of the 4 TF to add another layer to the genetic network regulating meristem activity.
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Surficial geology, Ujarattaak Point, Nunavut, NTS 56-P/15 and 16. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/329414.
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This new surficial geology map product represents the conversion of Open File 5016, map 4 (Little, 2006) and its legend only, using the Geological Survey of Canada's Surficial Data Model (SDM version 2.3.14) (Deblonde et al., 2018). All geoscience knowledge and information from Open File 5016, map 4 that conformed to the SDM were maintained during the conversion process. Supplementary legacy information (descriptive notes) on the original map is not included here. Limited legacy information was added to complement the converted geoscience data. This consists of striations (McMartin et al., 2003). It is identified in the accompanying geodatabase. The purpose of converting legacy map data to a common science language and common legend is to enable and facilitate the efficient digital compilation, interpretation, management, and dissemination of geological map information in a structured and consistent manner. This provides an effective knowledge-management tool designed around a geodatabase that can expand following the type of information to appear on new surficial geology maps.