Search results for "Q1"
showing 10 items of 447 documents
Expecting the unexpected: Quantifying the persistence of unexpected hypersurfaces
2021
If $X \subset \mathbb P^n$ is a reduced subscheme, we say that $X$ admits an unexpected hypersurface of degree $t$ for multiplicity $m$ if the imposition of having multiplicity $m$ at a general point $P$ fails to impose the expected number of conditions on the linear system of hypersurfaces of degree $t$ containing $X$. Conditions which either guarantee the occurrence of unexpected hypersurfaces, or which ensure that they cannot occur, are not well understand. We introduce new methods for studying unexpectedness, such as the use of generic initial ideals and partial elimination ideals to clarify when it can and when it cannot occur. We also exhibit algebraic and geometric properties of $X$ …
Cox ring of the generic fiber
2017
Abstract Given a surjective morphism π : X → Y of normal varieties satisfying some regularity hypotheses we prove how to recover a Cox ring of the generic fiber of π from the Cox ring of X. As a corollary we show that in some cases it is also possible to recover the Cox ring of a very general fiber, and finally we give an application in the case of the blowing-up of a toric fiber space.
Removable sets for intrinsic metric and for holomorphic functions
2019
We study the subsets of metric spaces that are negligible for the infimal length of connecting curves; such sets are called metrically removable. In particular, we show that every totally disconnected set with finite Hausdorff measure of codimension 1 is metrically removable, which answers a question raised by Hakobyan and Herron. The metrically removable sets are shown to be related to other classes of "thin" sets that appeared in the literature. They are also related to the removability problems for classes of holomorphic functions with restrictions on the derivative.
2-(1,3-Oxazolin-2-yl)pyridine and 2,6-bis(1,3-oxazolin-2-yl) pyridine
2018
The data presented in this article are related to research articles “Titanium and vanadium catalysts with oxazoline ligands for ethylene-norbornene (co)polymerization (Ochędzan-Siodłak et al., 2018). For the title compounds, 2-(1,3-oxazolin-2-yl)pyridine (Py-ox) and 2,6-bis(1,3-oxazolin-2-yl)pyridine (Py-box), the single-crystal X-ray diffraction measurement together with NMR, GC, MS, DSC analysis, like also the method of crystallization are presented. Keywords: Ligands, Oxazoline, Pyridine, Conformation, Association
Correlation Analysis between External Factors and Students’ Physics Learning Achievement
2018
Research was conducted to determine whether there is 1) the relationship between the state of the family of learning achievement, 2) the relationship between the state schools of learning achievement, 3) the relationship between communities of learning achievement, and 4) the relationship between the state of the family, school and community environment against learning achievement. This research is associative quantitative correlational analysis techniques. The results showed: 1) There is a positive relationship between the state of the family of learning achievement, the result of the calculation shows r table> count r ie 0.51 > 0.38, 2) There is a positive relationship between the …
Annual effective dose and excess life time cancer risk assessment from tobacco plants
2019
Cigarette smoking is one of the pathways that might cause radiation exposure due to the presence of radioactive elements in tobacco leaves used in the manufacture of cigarettes. From the health point of view, the knowledge of radioactivity content of the various radionuclides in tobacco leaves and their derivative products is important to assess the radiological effects associated with tobacco smoking for smokers. In this work, naturally occurring radionuclides 226Ra, 232Th and 40K and man-made 137Cs were measured in tobacco using gamma-ray spectrometry. Results show that the average concentrations of 226Ra, 232Th and 40K vary from 4.30 ± 0.2 to 11.85 ± 0.7 (average 8.17), 1.35 ± 0.1 to 16.…
How science teachers learn to reflect by analyzing jointly observed lessons
2015
The aim of the article is to present a teacher's professional learning model implemented within the project PROFILES of FP7 Science in Society. The article reveals the contribution of the joint observation in real-life classroom environment and lesson analyses to the development of the capability of teachers' reflection skills. The survey of teachers, conclusions of experts and teachers' feedback all demonstrate that the model enhances the development of science and mathematics teachers' reflection skills. At the same time the article gives guidelines to follow when this model is practiced with different groups of teachers. Efficient teaching of inquiry skills in the school is impossible wi…
Estudi comparatiu de l’atenuació pragmàtica en la llengua catalana: converses col·loquials prototípiques-converses col·loquials perifèriques
2017
A comparative study on pragmatic mitigation in a corpus of colloquial conversations in Catalan has been conducted in this work. Its aim objective is to study mitigation in a contrastive way, that is to say, to examine the usage contrast of this pragmatic strategy amongst prototypical colloquial conversations and peripheral colloquial conversations. For this purpose, it was believed appropriate to previously explain conversational genre and colloquial register, that is to say, colloquial conversation and its characteristics. In order to conduct thus study, one’s own corpus has been complied (recorded and transcribed) consisting of five colloquial conversations: two prototypical ones and thre…
Le théâtre des vanités mondaines : le Bois de Boulogne dans les chroniques zoliennes
2018
francaisL’œuvre journalistique d’Emile Zola touche tous les aspects de la realite parisienne de son epoque : des sujets « serieux », sociaux et politiques, a ceux qu’on peut qualifier de legers, voire frivoles. L’existence de la gentry de la capitale sous le regne de Napoleon III compte, selon l’ecrivain, selon ces derniers, etant focalisee sur les apparences et sur un affichage ostentatoire de la richesse. En effet, la vanite s’avere etre le defaut principal de la belle societe parisienne du Second Empire, et le paraitre devient sa nouvelle religion. La scene preferee de la parade quotidienne des mondains est le Bois de Boulogne, recemment transforme en un parc a l’anglaise. L’article se p…
Rutas cognitivas de futuros maestros ante una situación comparativa de razones desiguales
2019
En esta investigación se analizan las rutas cognitivas que subyacen a las resoluciones de un grupo de futuros maestros ante una tarea de comparación de razones desiguales en el contexto de las ofertas comerciales. La revisión de la literatura y el análisis en profundidad de las componentes críticas de la tarea nos han permitido definir las dimensiones de análisis de las resoluciones. A partir de ellas hemos realizado un análisis cualitativo de corte interpretativo del cual se desprende que los participantes poseen un escaso desarrollo del pensamiento relativo. Un número importante de ellos presenta dificultades con la comparación de las cantidades relativas desiguales cuando estas se les pr…