295 research outputs found

    Hubungan Literasi Sains dengan Keterampilan Berpikir Kritis Siswa pada Materi Ikatan Kimia

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    This research aimed at knowing and describing the correlation between scientific literacy and student critical thinking skill on Chemical Bond lesson.  The research method was Quantitative Descriptive with Correlation Hypothesis testing.  This research was administered at Vocational High School of Telkom Pekanbaru.  The subjects of this research were the eleventh-grade students.  The objects of this research were scientific literacy and student critical thinking skill on Chemical Bond lesson.  The instruments of collecting the data were Chemical Bond questions based on scientific literacy indicators and critical thinking skill.  The questions and questionnaire were stated worthy, if they passed valid aspects.  The validity could be seen from validity result by using validation sheet.  The technique of analyzing the data was Product Moment Correlation with SPSS 21.0 program.  Based on the research findings, it was obtained that there was a significant difference between scientific literacy and student critical thinking skill on Chemical Bond lesson at Vocational High School of Telkom Pekanbaru.  The Hypothesis was analyzed by using Pearson Product Moment Correlation with α that was 0.05.  The correlation coefficient was 0.910 with probability that was 0.000.  It meant that there was a positive correlation between scientific literacy and student critical thinking skill on Chemical Bond lesson.            Keywords: Scientific Literacy, Critical Thinking Skill, Chemical Bon

    Ocean acidification limits temperature-induced poleward expansion of coral habitats around Japan

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    Using results from four coupled global carbon cycle-climate models combined with in situ observations, we estimate the effects of future global warming and ocean acidification on potential habitats for tropical/subtropical and temperate coral communities in the seas around Japan. The suitability of coral habitats is classified on the basis of the currently observed regional ranges for temperature and saturation states with regard to aragonite (Ωarag). We find that, under the "business as usual" SRES A2 scenario, coral habitats are projected to expand northward by several hundred kilometers by the end of this century. At the same time, coral habitats are projected to become sandwiched between regions where the frequency of coral bleaching will increase, and regions where Ωarag will become too low to support sufficiently high calcification rates. As a result, the habitat suitable for tropical/subtropical corals around Japan may be reduced by half by the 2020s to 2030s, and is projected to disappear by the 2030s to 2040s. The habitat suitable for the temperate coral communities is also projected to decrease, although at a less pronounced rate, due to the higher tolerance of temperate corals for low Ωarag. Our study has two important caveats: first, it does not consider the potential adaptation of the coral communities, which would permit them to colonize habitats that are outside their current range. Second, it also does not consider whether or not coral communities can migrate quickly enough to actually occupy newly emerging habitats. As such, our results serve as a baseline for the assessment of the future evolution of coral habitats, but the consideration of important biological and ecological factors and feedbacks will be required to make more accurate projections

    The use of Multidisciplinarity, Interdisciplinarity and Transdisciplinarity to develop the Critical and Scientific Spirit in the student

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    The construction of knowledge today requires a new posture of the researcher, requires a broader and holistic view, with the interaction of the various areas, both in the expansion and in the deepening in the treatment of complex studies. Thus, the objective of this work is to identify the pedagogical practices for the development of the critical scientific spirit in the student in the learning environment. With this research, it was possible to conclude that with pedagogical practices based on the practice of inter, multi and transdisciplinarity, it is possible to contribute to an autonomous society, transforming tacit knowledge into explicit knowledge to serve as a basic tool for social development, with capacity to share and incorporate new technologies and disseminate them to society to make its economic and social transformation

    Forecasting Particulate Matter Concentrations: Use of Unorganized Machines

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    Air pollution is an environmental issue studied worldwide, as it has serious impacts on human health. Therefore, forecasting its concentration is of great importance. Then, this study presents an analysis comprising the appliance of Unorganized Machines – Extreme Learning Machines (ELM) and Echo State Networks (ESN) aiming to predict particulate matter with aerodynamic diameter less than 2.5 m (PM2.5) and less than 10 m (PM10). The databases were from Kallio and Vallilla stations in Helsinki, Finland. The computational results showed that the ELM presented best results to PM2.5, while the ESN achieved the best performance to PM10

    Identifying Potential Risks and Benefits of Using Cloud in Distributed Software Development

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    Cloud-based infrastructure has been increasingly adopted by the industry in distributed software development (DSD) environments. Its proponents claim that its several benefits include reduced cost, increased speed and greater productivity in software development. Empirical evaluations, however, are in the nascent stage of examining both the benefits and the risks of cloud-based in-frastructure. The objective of this paper is to identify potential benefits and risks of using cloud in a DSD project conducted by teams based in Helsinki and Ma-drid. A cross-case qualitative analysis is performed based on focus groups con-ducted at the Helsinki and Madrid sites. Participants’ observations are used to supplement the analysis. The results of the analysis indicated that the main ben-efits of using cloud are rapid development, continuous integration, cost savings, code sharing, and faster ramp-up. The key risks determined by the project are dependencies, unavailability of access to the cloud, code commitment and inte-gration, technical debt, and additional support costs. The results revealed that if such environments are not planned and set up carefully, the benefits of using cloud in DSD projects might be overshadowed by the risks associated with it.Peer reviewe

    Locally targeted cytoprotection with dextran sulfate attenuates experimental porcine myocardial ischaemia/reperfusion injury

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    Aims Intravascular inflammatory events during ischaemia/reperfusion injury following coronary angioplasty alter and denudate the endothelium of its natural anticoagulant heparan sulfate proteoglycan (HSPG) layer, contributing to myocardial tissue damage. We propose that locally targeted cytoprotection of ischaemic myocardium with the glycosaminoglycan analogue dextran sulfate (DXS, MW 5000) may protect damaged tissue from reperfusion injury by functional restoration of HSPG. Methods and results In a closed chest porcine model of acute myocardial ischaemia/reperfusion injury (60 min ischaemia, 120 min reperfusion), DXS was administered intracoronarily into the area at risk 5 min prior to reperfusion. Despite similar areas at risk in both groups (39±8% and 42±9% of left ventricular mass), DXS significantly decreased myocardial infarct size from 61±12% of the area at risk for vehicle controls to 39±14%. Cardioprotection correlated with reduced cardiac enzyme release creatine kinase (CK-MB, troponin-I). DXS abrogated myocardial complement deposition and substantially decreased vascular expression of pro-coagulant tissue factor in ischaemic myocardium. DXS binding, detected using fluorescein-labelled agent, localized to ischaemically damaged blood vessels/myocardium and correlated with reduced vascular staining of HSPG. Conclusion The significant cardioprotection obtained through targeted cytoprotection of ischaemic tissue prior to reperfusion in this model of acute myocardial infarction suggests a possible role for the local modulation of vascular inflammation by glycosaminoglycan analogues as a novel therapy to reduce reperfusion injur

    A Single Gene Expression Set Derived from Artificial Intelligence Predicted the Prognosis of Several Lymphoma Subtypes; and High Immunohistochemical Expression of TNFAIP8 Associated with Poor Prognosis in Diffuse Large B-Cell Lymphoma

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    OBJECTIVES: We have recently identified using multilayer perceptron analysis (artificial intelligence) a set of 25 genes with prognostic relevance in diffuse large B-cell lymphoma (DLBCL), but the importance of this set in other hematological neoplasia remains unknown. METHODS AND RESULTS: We tested this set of genes (i.e., ALDOB, ARHGAP19, ARMH3, ATF6B, CACNA1B, DIP2A, EMC9, ENO3, GGA3, KIF23, LPXN, MESD, METTL21A, POLR3H, RAB7A, RPS23, SERPINB8, SFTPC, SNN, SPACA9, SWSAP1, SZRD1, TNFAIP8, WDCP and ZSCAN12) in a large series of gene expression comprised of 2029 cases, selected from available databases, that included chronic lymphocytic leukemia (CLL, n = 308), mantle cell lymphoma (MCL, n = 92), follicular lymphoma (FL, n = 180), DLBCL (n = 741), multiple myeloma (MM, n = 559) and acute myeloid leukemia (AML, n = 149). Using a risk-score formula we could predict the overall survival of the patients: the hazard-ratio of high-risk versus low-risk groups for all the cases was 3.2 and per disease subtype were as follows: CLL (4.3), MCL (5.2), FL (3.0), DLBCL not otherwise specified (NOS) (4.5), multiple myeloma (MM) (5.3) and AML (3.7) (all p values 60 years, high serum levels of soluble IL2RA, a non-GCB phenotype (cell-of-origin Hans classifier), moderately higher MYC and Ki67 (proliferation index), and high infiltration of the immune microenvironment by CD163-positive tumor associated macrophages (CD163+TAMs). CONCLUSIONS: It is possible to predict the prognosis of several hematological neoplasia using a single gene-set derived from neural network analysis. High expression of TNFAIP8 is associated with poor prognosis of the patients in DLBCL

    Ram pressure feeding super-massive black holes

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    When supermassive black holes at the center of galaxies accrete matter (usually gas), they give rise to highly energetic phenomena named Active Galactic Nuclei (AGN). A number of physical processes have been proposed to account for the funneling of gas towards the galaxy centers to feed the AGN. There are also several physical processes that can strip gas from a galaxy, and one of them is ram pressure stripping in galaxy clusters due to the hot and dense gas filling the space between galaxies. We report the discovery of a strong connection between severe ram pressure stripping and the presence of AGN activity. Searching in galaxy clusters at low redshift, we have selected the most extreme examples of jellyfish galaxies, which are galaxies with long tentacles of material extending for dozens of kpc beyond the galaxy disk. Using the MUSE spectrograph on the ESO Very Large Telescope, we find that 6 out of the 7 galaxies of this sample host a central AGN, and two of them also have galactic-scale AGN ionization cones. The high incidence of AGN among the most striking jellyfishes may be due to ram pressure causing gas to flow towards the center and triggering the AGN activity, or to an enhancement of the stripping caused by AGN energy injection, or both. Our analysis of the galaxy position and velocity relative to the cluster strongly supports the first hypothesis, and puts forward ram pressure as another, yet unforeseen, possible mechanism for feeding the central supermassive black hole with gas.Comment: published in Nature, Vol.548, Number 7667, pag.30
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