1,081 research outputs found
Implementing an SPM Controller with LabVIEW
The purpose of this article is to reduce the barrier of developing a house-made scanning probe microscope(SPM). Here in this paper,we cover all the details of programming an SPM controller with LabVIEW. The main controller has three major sequential portions. They are system initialization portion,scan control and image display portion and system shutdown portion. The most complicated and essential part of the main controller is the scan control and image display portion, which is achieved with various parallel tasks. These tasks are scan area and image size adjusting module, Y-axis scan control module, Xaxis scan and image transferring module, parameters readjusting module,emergency shutdown module,etc. A NI7831 RFPGA board is used to output the control signals and utilize the Z-axis real-time feedback controls.The system emergency shutdown is also carried out by the FPGA module. Receiving the shutdown command from the main controller,the FPGA board will move the probe to its XYZzero position, turn off all the high voltage control signals and also eliminate the possible oscillations in the system. Finally, how to operate the controller is also briefly introduced. That messy wires fly back and forth is the main drawback of LabVIEW programming. Especially when the program is complicated,this problem becomes more serious. We use a real example to show how to achieve complex functionalities with structural programming and parallel multi-task programming. The actual code showed in this paper is clear, intuitive and simple. Following the examples showed in this paper, readers are able to develop simple LabVIEW programs to achieve complex functionalities
Género, ¿mujer y hombre únicamente?
Géneros. Así, en plural y en sentido multidireccional, es necesario que entendamos otras perspectivas sociopolíticasacerca del concepto de género.
Los feminismos, en su diversidad, han contribuido a repensarlo a partir de la contestación de la idea tradicional del binarismocomo la única posibilidad para representar nuestros cuerpos. En ese sentido, la femineidad y la masculinidad sondos categorías de clasificación humana que no solo pueden hibridarse o fusionarse en una persona, sino queademás, ellas pueden ir más allá de esa relación dual para buscar y hallar otros modos de expresión identitaria
A 4-Layer Method of Developing Integrated Sensor Systems With Lab VIEW
System integrity is important for fast and accurate measurement and control. LabVIEW is widely used in education and industry. Many LabVIEW codes are hard to be read and shown because of their 2D topology. In order to simplify the programming, a 4-layer model of developing sensor or measurement systems with LabVIEW is proposed in this paper. The purpose of this paper is to show the readers how to design simple, clear and strong automated systems with LabVIEW. Using a Sensirion SHT75 humidity sensor and an NI USB6008 DAQ board as an example, this paper describes the steps of developing a sensor system from the physical layer to application layer in detail. In layer 2, port selection and signal regulation are demonstrated. In layer 3, timing waveform analysis and synthesis, state diagram analysis, instruction set design, micro operation and fault tolerance designs are demonstrated. In layer 4, data visualization is covered with a vivid example. Programmers found it was hard to show readers their LabVIEW codes because many LabVIEW codes occupy several screens. A layer model simplifies the programming, so one is able to show a medium size LabVIEW code easily
Examining the Role of Environment in a Comprehensive Sample of Compact Groups
(Abridged) Compact groups, with their high number densities, small velocity
dispersions, and an interstellar medium that has not been fully processed,
provide a local analog to conditions of galaxy interactions in the earlier
universe. The frequent and prolonged gravitational encounters that occur in
compact groups affect the evolution of the constituent galaxies in a myriad of
ways, for example gas processing and star formation. Recently, a statistically
significant "gap" has been discovered mid-infrared IRAC colorspace of compact
group galaxies. This gap is not seen in field samples and is a new example of
how the compact group environment may affect the evolution of member galaxies.
In order to investigate the origin and nature of this gap, we have compiled a
sample of 49 compact groups. We find that a statistically significant deficit
of galaxies in this gap region of IRAC colorspace is persistant in this sample,
lending support to the hypothesis that the compact group environment inhibits
moderate SSFRs. We note a curvature in the colorspace distribution, which is
fully consistent with increasing dust temperature as the activity in a galaxy
increases. This full sample of 49 compact groups allows us to subdivide the
data according to physical properties of the groups. An analysis of these
subsamples indicates that neither projected physical diameter nor density show
a trend in colorspace within the values represented by this sample. We
hypothesize that the apparent lack of a trend is due to the relatively small
range of properties in this sample. Thus, the relative influence of stochastic
effects becomes dominant. We analyze spectral energy distributions of member
galaxies as a function of their location in colorspace and find that galaxies
in different regions of MIR colorspace contain dust with varying temperatures
and/or PAH emission.Comment: 24 pages, 13 figures. Accepted for publication in The Astronomical
Journa
El proceso de resignificación de la praxis docente y curricular desde la perspectiva de la implementación de los proyectos pedagógicos productivos
This investigative process around the search for resignification of the teaching and curricular praxis from the perspective of the implementation of productive pedagogical projects, constitutes a valuable scenario, in a school context nuanced by curricular fragmentation and traditional pedagogical practices, which They have been generating a certain type of demotivation in students, a situation that is reflected in the marked disinterest of young people in their life project and the low results in external tests.
Taking as theoretical referents productive pedagogical projects, project-based learning and matters concerning curricular theory, looking for key clues to support this process; all this framed in a methodological design enlightened by the qualitative approach, the hermeneutical historical paradigm and the ethnographic method, applying some instruments to the teachers focused on this investigative process, such as the survey and the interview, taking advantage of the different digital platforms taking into account the limitations imposed on the direct interaction with the actors caused by the pandemic that is hitting the planet at the present time.
The research yielded some very important results in the framework of institutional resignification, especially in the teaching practice and in the curriculum, to the extent that through the same research, teachers review their pedagogical practices, adjusting them more to the needs of the student. moment and of course to those caused by the current health emergency, and in the resignification of the curriculum, a process of displacement from the disciplinary and closed perspective towards an interdisciplinary curriculum begins, having as a transversal axis the productive pedagogical projects.Este proceso investigativo alrededor de la búsqueda de resignificación de la praxis docente y curricular desde la perspectiva de la implementación de los proyectos pedagógicos productivos, se constituye en un escenario valioso, en un contexto escolar matizado por la fragmentación curricular y unas prácticas pedagógicas tradicionales, que vienen generando cierto tipo de desmotivación en los estudiantes, situación que se refleja en el desinterés marcado de los jóvenes por su proyecto de vida y los bajos resultados en las pruebas externas.
Teniendo como referentes teóricos los proyectos pedagógicos productivos, el aprendizaje basado en proyectos y lo concerniente a la teoría curricular, buscando pistas claves para fundamentar este proceso; todo esto enmarcado en un diseño metodológico iluminado por el enfoque cualitativo, el paradigma histórico hermenéutico y el método etnográfico, aplicando unos instrumentos a los docentes focalizados en este proceso investigativo, tales como la encuesta y la entrevista, aprovechando las diferentes plataformas digitales teniendo en cuenta las limitaciones impuestas en la interacción directa con los actores originadas por la pandemia que azota al planeta en los actuales momentos.
La investigación arrojo unos resultados muy importantes en el marco de la resignificación institucional, sobre todo en la praxis docente y en la curricular, en la medida que a través de la misma investigación, los docentes revisan sus prácticas pedagógicas, ajustándolas más a las necesidades del momento y por supuesto a las provocadas por la actual emergencia sanitaria, y en resignificación del currículo se inicia un proceso de desplazamiento desde la mirada disciplinar y cerrada hacia un currículo interdisciplinar, teniendo como eje transversal los proyectos pedagógicos productivos
Reproductive Modes in Onion Thrips (Thysanoptera: Thripidae) Populations from New York Onion Fields
Thrips exhibit different reproductive modes including thelytoky (females produced from unfertilized eggs), arrhenotoky (males produced from unfertilized eggs and females produced from fertilized eggs) and deuterotoky (females and males produced from unfertilized eggs). We investigated patterns of reproductive modes in onion thrips, Thrips tabaci Lindeman, populations and potential effects of the bacterium Wolbachia and temperature on these modes. We also examined the possibility that male-producing T. tabaci populations were resistant to the frequently used insecticides, lambda-cyhalothrin and methomyl. In New York during 2002-2004, T. tabaci populations were sampled from 20 onion fields and reproductive mode was determined by identifying sex of progeny from virgins. Half of the populations were thelytokous and half were a mix of thelytokous, arrhenotokous and deuterotokous individuals, which we refer to as a male-producing population. In two of four cases, the reproductive mode of a population from the same onion field changed across years, suggesting that populations either mix or an external factor caused the change. To address the latter, we speculated that Wolbachia or high temperature mediated reproductive modes. Samples of T. tabaci representing each reproductive mode were examined for Wolbachia using diagnostic polymerase chain reaction (PCR), but it was not detected. Cytological examination of ovaries from two additional thelytokous lines also showed no evidence of Wolbachia. Similarly, high temperature did not affect sex allocation ratios in either thelytokous or male-producing populations. Male-producing T. tabaci populations were not positively correlated with resistance to lambda-cyhalothrin, or tolerance to methomyl. The role of the different reproductive modes in T. tabaci populations in onion fields remains unclea
Mid-Infrared Evidence for Accelerated Evolution in Compact Group Galaxies
We find evidence for accelerated evolution in compact group galaxies from the
distribution in mid-infrared colorspace of 42 galaxies from 12 Hickson Compact
Groups (HCGs) compared to the the distributions of several other samples
including the LVL+SINGS galaxies, interacting galaxies, and galaxies from the
Coma Cluster. We find that the HCG galaxies are not uniformly distributed in
colorspace, as well as quantitative evidence for a gap. Galaxies in the infall
region of the Coma cluster also exhibit a non-uniform distribution and a less
well defined gap, which may reflect a similarity with the compact group
environment. Neither the Coma Center or interacting samples show evidence of a
gap, leading us to speculate that the gap is unique to the environment of high
galaxy density where gas has not been fully processed or stripped.Comment: To appear in the Proceedings of the Galaxy Wars: Stellar Populations
and Star Formation in Interacting Galaxies Conferenc
Thousands of Single Nucleotide Polymorphisms in the Critically Endangered Kemp\u27s Ridley Sea Turtle (Lepidochelys kempii) Revealed by Double-Digest Restriction-Associated DNA Sequencing: Opportunities for Previously Elusive Conservation Genetics Research
Raltegravir in second-line antiretroviral therapy in resource-limited settings (SELECT): a randomised, phase 3, non-inferiority study
For second-line antiretroviral therapy, WHO recommends a boosted protease inhibitor plus nucleoside or nucleotide reverse transcriptase inhibitors (NRTIs). However, concerns about toxicity and cross-resistance motivated a search for regimens that do not contain NRTIs. We aimed to assess whether boosted lopinavir plus raltegravir would be non-inferior to boosted lopinavir plus NRTIs for virological suppression in resource-limited settings
Exploration of bacterial community classes in major human habitats
BACKGROUND: Determining bacterial abundance variation is the first step in understanding bacterial similarity between individuals. Categorization of bacterial communities into groups or community classes is the subsequent step in describing microbial distribution based on abundance patterns. Here, we present an analysis of the groupings of bacterial communities in stool, nasal, skin, vaginal and oral habitats in a healthy cohort of 236 subjects from the Human Microbiome Project. RESULTS: We identify distinct community group patterns in the anterior nares, four skin sites, and vagina at the genus level. We also confirm three enterotypes previously identified in stools. We identify two clusters with low silhouette values in most oral sites, in which bacterial communities are more homogeneous. Subjects sharing a community class in one habitat do not necessarily share a community class in another, except in the three vaginal sites and the symmetric habitats of the left and right retroauricular creases. Demographic factors, including gender, age, and ethnicity, significantly influence community composition in several habitats. Community classes in the vagina, retroauricular crease and stool are stable over approximately 200 days. CONCLUSION: The community composition, association of demographic factors with community classes, and demonstration of community stability deepen our understanding of the variability and dynamics of human microbiomes. This also has significant implications for experimental designs that seek microbial correlations with clinical phenotypes
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