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[en] A bidimensional classification for galaxies with active nuclei (N galaxies, Seyfert galaxies, quasars and BL Lac objects) based on a morphological and a spectroscopic criteria is proposed. It is suggested that a quasaar or an N galaxy should be called a Seyfert 1 if their spectrum shows broad Balmer lines; that an extragalatic star-like object should be called a quasar, even if it is has the spectrum of an BL Lac object, etc
[fr]On propose une classification bidimensionnelle des galaxies a noyau actif (galaxies N, galaxies de Seyfert, objets de type BL Lacertae et quasars), basee sur un critere morphologique et un critere spectroscopique. On suggere qu'un quasar ou une galaxie N doivent etre baptises galaxie de Seyfert de type 1 si leur spectre presente des raies de Balmer larges en emission; qu'un objet extragalactique d'aspect stellaire doit etre appele quasar meme si son spectre est celui d'un objet de type BL Lac, etc
[en] Cypsela of 26 species distributed in 9 genera of the tribe Senecioneae were examined from Pakistan. Micromorphological characters of cypsela in this group are not only found useful for assessing relationship but they are also useful for the delimitation of taxa both at the generic and specific levels, except that of the genera Senecio and Doronicum which could not be clearly separated as they do not have exclusive cypsela features. (author)
[en] The present paper highlights problems associated with the currently–accepted taxonomy of brown bear, Ursus arctos, and their consequences for conservation at the European level. The enormous morphological variability within Ursus arctos is not acknowledged in current taxonomy and conservation practice. Seven major clades are recognized in Ursus arctos by molecular researchers, and although Western Europe maintains most of the populations belonging to the relict Clade 1 brown bear lineage, no reference to this is made in current conservation policy. Furthermore, the tiny population of Apennine brown bears, characterized by unique skull morphology, is not even recognized as a distinct ESU (evolutionari significant unit) by current European legislation, nor is it included in the IUCN Red List. This may have serious consequences as brown bear conservation in Western Europe has been mainly based on restocking and reintroduction programs. (Author)
[en] The students learning outcomes clarify what students should know and be able to demonstrate after completing their course. So, one of the issues on the process of teaching and learning is how to assess students' learning. This paper describes an application of the dichotomous Rasch measurement model in measuring the cognitive process of engineering students' learning of mathematics. This study provides insights into the perspective of 54 engineering students' cognitive ability in learning Calculus III based on Bloom's Taxonomy on 31 items. The results denote that some of the examination questions are either too difficult or too easy for the majority of the students. This analysis yields FIT statistics which are able to identify if there is data departure from the Rasch theoretical model. The study has identified some potential misfit items based on the measurement of ZSTD where the removal misfit item was accomplished based on the MNSQ outfit of above 1.3 or less than 0.7 logit. Therefore, it is recommended that these items be reviewed or revised to better match the range of students' ability in the respective course.
[en] The report describes a set of categories for reporting industrial incidents and events involving human malfunction. The classification system aims at ensuring information adequate for improvement of human work situations and man-machine interface systems and for attempts to quantify ''human error'' rates. The classification system has a multifacetted non-hierarchical structure and its compatibility with Ispra's ERDS classification is described. The collection of the information in general and for quantification purposes are discussed. 24 categories, 12 of which being human factors-oriented, are listed with their respective subcategories, and comments are given. Underlying models of human data process and their typical malfuntions and of a human decision sequence are described. The work reported is a joint contribution to the CSNI Group of Experts on Human Error Data and Assessment
[en] The process by which a student learns is extremely complicated. Whether he is simply learning facts, laws or formulae, changing his values or mastering a skill the way in which his brain functions is impossible to describe. The idea of learning domains is put forward not to explain in biological terms what happens in the brain but simply to attempt to break the system down into simpler units so that the learning process can be organized in an easier, more systematic way. In the most commonly used description of this process, the one described by BLOOM, this is BLOOM's Taxonomy. In addition to, I'd like to compare with the work of Lewis (Levels of Knowledge and Understanding). As a result, let us discuss about the most effective method in teaching in order to supply high-quality education
[en] Current theories of spiral and bar structure predict a variety of pattern speed behaviors, calling for detailed, direct measurement of the radial variation of pattern speeds. Our recently developed Radial Tremaine-Weinberg (TWR) method allows this goal to be achieved for the first time. Here, we present TWR spiral pattern speed estimates for M101, IC 342, NGC 3938, and NGC 3344 in order to investigate whether spiral structure is steady or winding, whether spirals are described by multiple pattern speeds, and the relation between bar and spiral speeds. Where possible, we interpret our pattern speeds estimates according to the resonance radii associated with each (established with the disk angular rotation), and compare these to previous determinations. By analyzing the high-quality H I and CO data cubes available for these galaxies, we show that it is possible to determine directly multiple pattern speeds within these systems, and hence identify the characteristic signatures of the processes that drive the spiral structure. Even this small sample of galaxies reveals a surprisingly complex taxonomy, with the first direct evidence for the presence of resonant coupling of multiple patterns found in some systems, and the measurement of a simple single-pattern speed in others. Overall, this study demonstrates that we are now in a position to uncover more of the apparently complex physics that lies behind spiral structure.
[en] Spumaretroviruses, commonly referred to as foamy viruses, are complex retroviruses belonging to the subfamily Spumaretrovirinae, family Retroviridae, which naturally infect a variety of animals including nonhuman primates (NHPs). Additionally, cross-species transmissions of simian foamy viruses (SFVs) to humans have occurred following exposure to tissues of infected NHPs. Recent research has led to the identification of previously unknown exogenous foamy viruses, and to the discovery of endogenous spumaretrovirus sequences in a variety of host genomes. Here, we describe an updated spumaretrovirus taxonomy that has been recently accepted by the International Committee on Taxonomy of Viruses (ICTV) Executive Committee, and describe a virus nomenclature that is generally consistent with that used for other retroviruses, such as lentiviruses and deltaretroviruses. This taxonomy can be applied to distinguish different, but closely related, primate (e.g., human, ape, simian) foamy viruses as well as those from other hosts. This proposal accounts for host-virus co-speciation and cross-species transmission.
[en] This is a contribution to the knowledge of the freshwater algae of the Colombian Amazon region. Two of the 13 taxa are reported for the first time from Colombia and 10 are new records for the Colombian Amazon. Ecological characteristics are given for these desmids
[en] Recently, the CSNI directed WGRisk to set up a task group called DIGREL to initiate a new task on developing a taxonomy of failure modes of digital components for the purposes of PSA. It is an important step towards standardized digital I and C reliability assessment techniques for PSA. The objective of this paper is to provide a comparison of the failure mode taxonomies provided by the participants. The failure modes are classified in terms of their levels of detail. Software and hardware failure modes are discussed separately.