271 research outputs found

    The African Lungfish (\u3cem\u3eProtopterus dolloi\u3c/em\u3e): Ionoregulation and Osmoregulation in a Fish out of Water

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    Although urea production and metabolism in lungish have been thoroughly studied, we have little knowledge of how internal osmotic and electrolyte balance are controlled during estivation or in water. We tested the hypothesis that, compared with the body surface of teleosts, the slender African lungfish (Protopterus dolloi) body surface was relatively impermeable to water, Na+ and Cl- due to its greatly reduced gills. Accordingly, we measured the tritiated water (3H-H2O) flux in P. dolloi in water and during air exposure. In water, 3H-H2O efflux was comparable with the lowest measurements reported in freshwater teleosts, with a rate constant (K) of 17.6% body water h-1. Unidirectional ion fluxes, measured using 22Na+ and 36Cl-, indicated that Na+ and Cl- influx was more than 90% lower than values reported in most freshwater teleosts. During air exposure, a cocoon formed within 1 wk that completely covered the dorsolateral body surface. However, there were no disturbances to blood osmotic or ion (Na+, Cl-) balance, despite seven- to eightfold increases in plasma urea after 20 wk. Up to 13-fold increases in muscle urea (on a dry-weight basis) were the likely explanation for the 56% increase in muscle water content observed after 20 wk of air exposure. The possibility that muscle acted as a “water reservoir” during air exposure was supported by the 20% decline in body mass observed during subsequent reimmersion in water. This decline in body mass was equivalent to 28 mL water in a 100-g animal and was very close to the calculated net water gain (approximately 32 mL) observed during the 20-wk period of air exposure. Tritiated water and unidirectional ion fluxes on air-exposed lungfish revealed that the majority of water and ion exchange was via the ventral body surface at rates that were initially similar to aquatic rates. The 3H-H2O flux declined over time but increased upon reimmersion. We conclude that the slender lungfish body surface, including the gills, has relatively low permeability to water and ions but that the ventral surface is an important site of osmoregulation and ionoregulation. We further propose that an amphibian-like combination of ventral skin water and ion permeability, plus internal urea accumulation during air exposure, allows P. dolloi to extract water from its surroundings and to store water in the muscle when the water supply becomes limited

    Mobile Application with Augmented Reality to Improve the Process of Learning Sign Language

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    Language for a long time is an indispensable tool for society, since it allows communication and interaction between people. Learning sign language is a very big problem, either because access to information is scarce, there are no interpreters of this language or because learning of this language is not taught from an early age. This document shows the development of a mobile application with augmented reality following the mobile methodology and determining the influence it has on the Peruvian sign language learning process, with a sample of 30 students as a control group and an experimental group. It started with a performance percentage of 23 percent and using the mobile application significantly improved the performance of the sign language student by 65 percent

    The SOAR Optical Imager

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    The SOAR Optical Imager (SOI) is the commissioning instrument for the 4.2-m SOAR telescope, which is sited on Cerro Pachón, and due for first light in April 2003. It is being built at Cerro Tololo Inter-American Observatory, and is one of a suite of first-light instruments being provided by the four SOAR partners (NOAO, Brazil, University of North Carolina, Michigan State University). The instrument is designed to produce precision photometry and to fully exploit the expected superb image quality of the SOAR telescope, over a 6x6 arcmin field. Design goals include maintaining high throughput down to the atmospheric cut-off, and close reproduction of photometric passbands throughout 310-1050nm. The focal plane consists of a two-CCD mosaic of 2Kx4K Lincoln Labs CCDs, following an atmospheric dispersion corrector, focal reducer, and tip-tilt sensor. Control and data handling are within the LabVIEW-Linux environment used throughout the SOAR Project

    ISPI: the infared side port imager for the CITO 4-m telescope

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    The new operations model for the CTIO Blanco 4-m telescope will use a small suite of fixed facility instruments for imaging and spectroscopy. The Infrared Side Port Imager, ISPI, provides the infrared imaging capability. We describe the optical, mechanical, electronic, and software components of the instrument. The optical design is a refractive camera-collimator system. The cryo-mechanical packaging integrates two LN2-cooled dewars into a compact, straightline unit to fit within space constraints at the bent Cassegrain telescope focus. A HAWAII 2 2048 x 2048 HgCdTe array is operated by an SDSU II array controller. Instrument control is implemented with ArcVIEW, a proprietary LabVIEW-based software package. First light on the telescope is planned for September 2002

    Gain of gene regulatory network interconnectivity at the origin of vertebrates

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    Signaling pathways control a large number of gene regulatory networks (GRNs) during animal development, acting as major tools for body plan formation [A. Pires-daSilva, R. J. Sommer, Nat. Rev. Genet. 4, 39-49 (2003)], although only a few of these pathways operate during this period [J. J. Sanz-Ezquerro, A. E. Munsterberg, € S. Stricker, Front. Cell Dev. Biol. 5, 76 (2017)]. Moreover, most of them have been largely conserved during metazoan evolution [L. S. Babonis, M. Q. Martindale, Philos. Trans. R. Soc. Lond. B Biol. Sci. 372, 20150477 (2017)]. How evolution has generated a vast diversity of animal morphologies with such a limited number of tools is still largely unknown. Here, we show that gain of interconnectivity between signaling pathways and the GRNs they control may have critically contributed to the origin of vertebrates. We perturbed the retinoic acid, Wnt, FGF, and Nodal signaling pathways during gastrulation in the invertebrate chordate amphioxus and zebrafish and compared the effects on gene expression and cis-regulatory elements (CREs). We found that multiple developmental genes gain response to these pathways through vertebrate-specific CREs. Moreover, in contrast to amphioxus, many of these CREs responded to multiple pathways in zebrafish, which reflects their high interconnectivity. Furthermore, we found that vertebrate-specific cell types are more enriched in highly interconnected genes than in tissues with more ancient origin. Thus, the increase of CREs in vertebrates integrating inputs from different signaling pathways probably contributed to gene expression complexity and to the formation of new cell types and morphological novelties in this lineage.This project has received funding from the European Research Council under the European Union’s Horizon 2020 research and innovation program (Grant agreement no. 740041) and the Spanish Ministerio de Economía y Competitividad (Grants BFU2016-74961-P and PID2019-103921GB-I00 to J.L.G.-S. and J.J.T.). This work was also supported by the institutional grant Unidad de Excelencia María de Maeztu (Grant MDM-2016-0687 to the Department of Gene regulation and morphogenesis of Centro Andaluz de Biología del Desarrollo). M.F. was funded by the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement [#800396]. M.S., H.E., and S.B. were supported by the CNRS, and H.E. and S.B. additionally by Agence Nationale de la Recherche (ANR) CHORELAND (Grant ANR-16-CE12-0008-01) and the Institut Universitaire de France. Y.-H.S. and J.-K.Y. are supported by intramural funds from Academia Sinica and grants from Ministry of Science and Technology, Taiwan (Grants 110-2326-B-001-006 to Y.-H.S. and 110-2621-B-001-001-MY3 to J.-K.Y.)

    Process mining for healthcare: Characteristics and challenges

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    [EN] Process mining techniques can be used to analyse business processes using the data logged during their execution. These techniques are leveraged in a wide range of domains, including healthcare, where it focuses mainly on the analysis of diagnostic, treatment, and organisational processes. Despite the huge amount of data generated in hospitals by staff and machinery involved in healthcare processes, there is no evidence of a systematic uptake of process mining beyond targeted case studies in a research context. When developing and using process mining in healthcare, distinguishing characteristics of healthcare processes such as their variability and patient-centred focus require targeted attention. Against this background, the Process-Oriented Data Science in Healthcare Alliance has been established to propagate the research and application of techniques targeting the data-driven improvement of healthcare processes. This paper, an initiative of the alliance, presents the distinguishing characteristics of the healthcare domain that need to be considered to successfully use process mining, as well as open challenges that need to be addressed by the community in the future.This work is partially supported by ANID FONDECYT 1220202, Direccion de Investigacion de la Vicerrectoria de Investigacion de la Pontificia Universidad Catolica de Chile-PUENTE [Grant No. 026/2021] ; and Agencia Nacional de Investigacion y Desarrollo [Grant Nos. ANID-PFCHA/Doctorado Nacional/2019-21190116, ANID-PFCHA/Doctorado Nacional/2020-21201411] . With regard to the co-author Hilda Klasky, this manuscript has been authored by UT-Battelle, LLC, under contract DE-AC05-00OR22725 with the US Department of Energy (DOE) . The US government retains and the publisher, by accepting the article for publication, acknowledges that the US government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for US government purposes. DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan)Munoz Gama, J.; Martin, N.; Fernández Llatas, C.; Johnson, OA.; Sepúlveda, M.; Helm, E.; Galvez-Yanjari, V.... (2022). Process mining for healthcare: Characteristics and challenges. Journal of Biomedical Informatics. 127:1-15. https://doi.org/10.1016/j.jbi.2022.10399411512

    The SOAR Optical Imager

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    The SOAR Optical Imager (SOI) is the commissioning instrument for the 4.2-m SOAR telescope, which is sited on Cerro Pachón, and due for first light in April 2003. It is being built at Cerro Tololo Inter-American Observatory, and is one of a suite of first-light instruments being provided by the four SOAR partners (NOAO, Brazil, University of North Carolina, Michigan State University). The instrument is designed to produce precision photometry and to fully exploit the expected superb image quality of the SOAR telescope, over a 6x6 arcmin field. Design goals include maintaining high throughput down to the atmospheric cut-off, and close reproduction of photometric passbands throughout 310-1050nm. The focal plane consists of a two-CCD mosaic of 2Kx4K Lincoln Labs CCDs, following an atmospheric dispersion corrector, focal reducer, and tip-tilt sensor. Control and data handling are within the LabVIEW-Linux environment used throughout the SOAR Project
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