showing 36 of ~574560 from 574555 documents
Introduction
1990
Математика,1
1990
Improved Method for Orbital Elements Differential Correction.
1990
As was pointed out by IAU in 1976, an important problem in fundamental astronomy is the improvement of the vernal equinox and equator positions. To this aim, it is necessary to know the accurate values of minor planets orbital elements. The classical methods of orbital elements differential corrections are based on linking the observations at different epochs considering equal derivatives respect to the initial and osculating elements. In this paper we present an improved method in which the least squares matrix coefficients is calculated from the integration of the Lagrange planetary equations and its derivatives.
C3 reference typing report and nomenclature revision.
1990
As the result of reference typing, two 'new' variants could be provisionally accepted (C3F045 and C3F015). The list of variants of the C3 polymorphism includes now 2 common and 29 rare variants.
Double and triple calix[4]arenis connected via the oxygen functions
1990
New macrocyclic molecules are described containing two or three p-tert-butylcalix[4]arene subunits connected via their oxygen atoms. These macrocycles are available by two general methods which are capable of producing assemblies with bridges of varying rigidity and length.
Arjen ja tieteen välissä : sosiaalityön akatemisoitumisen tarkastelua
1990
Sosiaalityön akateeminen asema, tiedepohja ja kohteena oleva todellisuus eivät ole itsestäänselviä eikä samoja kaikkialla. Akateemisuuden erityishaasteena on oppiaineen ammatillinen orientaatio. Sosiaalityön tiedepohjaa suhteellistavaa ja arvioivaa keskustelua käydään jatkuvasti. Myös sosiaalityön tutkimuksen ja toiminnan kohteena oleva todellisuus on sopimuksenvaraista, yhteiskunnallisesti konstituoitunutta. Muissa maissa voi tavata aivan toisella tavalla määräytynyttä sosiaalityön opetusta ja tutkimusta. Tieteenharjoittajan itseymmärrykselle onkin hyödyllistä kysellä, mitkä tekijät ovat ohjanneet suomalaisen sosiaalityön akatemisoitumisprosessia tietynlaiseksi. Pyrin seuraavassa valaisema…
How to combine tools and methods in practice— a field study
1990
In spring 1989 we surveyed the experiences of some Finnish companies in methodology modelling (metamodelling) and adaptation of tools and methodologies to each other (methodology adaptation). The companies represented software production, banking, wood and metal industry, and wholesale trade. The study was carried out as a field study where we interviewed method developers, systems analysts and their supervisors. The goal of the survey was to find out whether there was need for metamodelling or methodology adaptation in general and how this need had been satisfied. The study shows that a little experience had been gained in adapting data dictionaries to methodologies but no such attempts ha…
Inhibition of ethoxyresorufin deethylase activity by natural flavonoids in human and rat liver microsomes
1990
Several flavones and flavonols (chrysin, quercetin, luteolin, flavone and 7, 8-benzoflavone) were found to inhibit ethoxyresorufin deethylase (EROD) activity in human and rat liver microsomes. In man, molecules without hydroxyl groups are more powerful inhibitors than polyhydroxylated flavonoids (7, 8-benzoflavone greater than flavone greater than chrysin greater than luteolin greater than quercetin greater than morin). In rat, chrysin was the strongest inhibitor and the less effective were morin and 7,8-benzoflavone. For all molecules human microsomes were more sensitive than rat microsomes. The most important difference concerned 7,8-benzoflavone which was 10,000-fold more potent in man.
Le donne e l'uccisione dell'invasore. Un tema mitico eurasiatico?
1990
Alcune narrazioni mitiche presentano una convergenza strutturale che in alcuni casi trova spiegazione di natura storica. E' il caso del mito delle figlie di Kokalos, re sicano della Sicilia, che respingono con l'inganno l'assedio di Minosse. Si propone una comparazione con la storia biblica di Giuditta che presenta più di un elemento di convergenza. Poi si indica anche una possibile mediazione culturale che spieghi la diffusione del tema narrativo, grazie all'esame del documento epigrafico noto con il nome di Cronaca di Lindo.
Génesis de avenidas en pequeñas cuencas semiáridas: la rambla del Poyo (València)
1990
El estudio de la génesis y modelización de avenidas en ambientes semiáridos está muy condicionado por la escasez y baja calidad de los datos hidrológicos. En el ámbito valenciano, la reciente instalación de la red SAIH-JÚCAR (Sistema Automático de Información Hidrológica) abre nuevas posibilidades. Basándose en los datos aportados por esta red, el presente trabajo analiza la crecida ocurrida en la Rambla de Poyo (Valencia) durante los días 11 y 12 de noviembre de 1988. Bajo una óptica sistémica se estudia el comportamiento hidrogeomorfológico de la rambla en función de las características físicas de la cuenca, de la precipitación y de la escorrentía superficial. Asimismo se ensaya la viabil…
Sobre la “Teoría de la acción comunicativa” de J. Habermas
1990
Sorprende que un autor como Habermas haya podido atraer sobre sí la atención de un público que no esté estrictamente interesado en cuestiones de fundamentos de las ciencias sociales. Y no porque estas cuestiones resulten especialmente misteriosas o no puedan interesar a muchos; estas cuestiones son de muchos o de pocos en el mismo grado en que son de muchos o de pocos las cuestiones de fundamentos de cualquier otra ciencia. Por lo general son de pocos, no en ningún sentido elitista, sino en el sentido de cuestiones especializadas. «Teoría de la acción comunicativa» de Habermas está dirigida a aquel que esté interesado en cuestiones de fundamentos en las ciencias sociales y, sin embargo, oh …
Reflexions sobre el problema de la veritat
1990
Aquest article exposa els problemes centrals de les dues concepcions sobre la veritat que ens ha llegat la tradició filosòfica, la teoria de la correspondència i la teoria coherentista, assenyalant com a tret comú d’aquestes el fet que plantegen el problema de la veritat centrant-se en enunciats aïllats. S'esbossa una proposta alternativa consistent en combinar la tesi intuïcionista de Dummett amb l’holisme de Quine, proposta que situa la veritat com una construcció no d’enunciats individuals sinó de sistemes cognitius que interpreten la realitat.
Wachstumsgeschwindigkeit, Angiogenese, Durchblutung und lokale Gewebsoxygenierung ras-Onkogen-induzierter Tumoren
1990
Bosartiges Wachstum beruht auf der Aktivierung sog. Onkogene oder auf dem Verlust von Tumorsuppressor-Genen. Solche genetischen Veranderungen konnen direkt die Sensibilitat der Tumorzellen fur verschiedene Therapieformen modulieren. Weiterhin kann sich sekundar in Tumoren ein besonderes Mikromilieu auspragen, das das biologische Verhalten der Tumorzellen beeinflust. Da bislang nur sparliche Daten vorliegen, wurden mogliche Zusammenhange zwischen einer Onkogen-Aktivierung, dem Wachstumsverhalten, der Durchblutung und der Oxygenierung maligner Tumoren an Onkogen-transformierten Rattenfibroblasten untersucht.
Identification des phases sous-hydratées du sulfate de calcium
1990
L'utilisation de moyens et de procedures experimentales adaptees a permis d’identifier chimiquement et structuralement deux formes sous-hydratees de sulfate de calcium : CaSO 4 , 0,5 H 2 O et CaSO 4 , 0,6 H 2 O.Avec l’hanhydrite soluble - γ-CaSO 4 - a laquelle elles s'apparentent structuralement ce sont les trois phases distinctes entrant dans la constitution du plâtre.
A SEARCH FOR PAIR-PRODUCED CHARGED HIGGS BOSONS IN Z0 DECAYS
1990
The utilitarian representation of sport in Rumania, a brake in the development of leisure practice. Since the countries of central Europe entered the liberal sphere influence, the consumptions of possessions and services develop there. We observe a movement of tutellaire and ideological emancipation of the sports organizations, but the practice of popular physical activities delays developing. If, on the ground, we notice the appearance of an structured professionally offer, contrary to all expectations, it does not pull a real increase of consumption. This situation which rises in inferred paradox a cultural interrogation on the previous history of these brakes. Historically, the sport dur…
Considerazioni sull'applicabilità dell'oblazione ai reati tributari
1990
Il lavoro affronta il tema dell’applicabilità dell’oblazione discrezionale nel giudizio penal-tributario, disciplinata dall’art. 162 bis c.p. Viene approfondita l’analisi dell’interesse tutelato dal legislatore penal-tributario, in considerazione del fatto che, sotto la vigenza della l. n. 516/1982, le fattispecie dei reati contravvenzionali prescindono dall’avvenuta realizzazione dell’evasione, e si configurano come reati di pericolo. Il giudice penale chiamato a pronunciarsi sull’istanza di oblazione opera in un contesto in cui non vige la pregiudiziale tributaria (abrogata con l’art. 13, l. n. 516/1982) e le fattispecie incriminatrici non sono legate né al quantum evaso, né all’effettivi…
Studies on Instabilities and Patterns in Evaporating Liquids at Reduced Pressure and/or Microwave Irradiation
1990
This paper summarizes our recent experimental and theoretical work on the instabilities in liquids and at interfaces which form during evaporation at reduced pressure and/or microwave irradiation. We have observed a variety of patterns (Benard rolls, Marangoni waves, Hickman interface deformations) which depend on the value of the reduced pressure and the power of the incident beam.
Reference Standards for Software Evaluation
1990
AbstractThe field of automated ECG analysis was one of the earliest topics in Medical Informatics and may be regarded as a model both for computer-assisted medical diagnosis and for evaluating medical diagnostic programs. The CSE project has set reference standards of two kinds: In a broad sense, a standard how to perform a comprehensive evaluation study, in a narrow sense, standards as specific references for evaluating computer ECG programs. The evaluation methodology used within the CSE project is described as a basis for presentation of results which are published elsewhere in this issue.
Opinión Sobre el Aborlo Entre Estudiantes de Medicina
1990
Pictorial information retrieval with uncertain knowledge
1990
In the paper an integrated pictorial database is described. The design of the data management requires many efforts to preserve consistency and integrity. The retrieval operations are designed to support a uniform view of heterogeneous information including uncertain ones; in this last case, non-standard techniques have to be developed. Applications to astronomical images and an outline of the implementation status are given.
HERMIA: An Heterogeneous and Reconfigurable Machine for Image Analysis
1990
In this paper is described the general architecture of an Heterogeneous and Reconfigurable Machine for Image Analysis (HERMIA); the first prototype of the system has been developed at the University of Palermo. Conventional hardware has been used in order to emulate the machine and evaluate the system performance Preliminary results are presented and discussed.
Application of the memory effects in CAD spectra of deprotonated heterosides for fruit monoterpenyl glycoside analysis
1990
International audience
Conservación y restauración de materiales de archivo
1990
El papel y el pergamino son soportes tradicionales en la documentación de archivo y bibliotecas. Ambos materiales están constituidos por materia orgánica y por tanto las condiciones ambientales, temperatura y humedad, repercuten sobre estas sustancias y provocan la proliferación de agentes biológicos que son capaces de alterar la estructura de estas moléculas. En ocasiones algunos tipos de papel poseen ciertas sustancias causantes de su propia degradación con independencia de la actividad de agentes externos. Las tintas ácidas constituyen una causa de alteración muy frecuente en la documentación. La conservación de documentos degradados exige un cuidado y atención que incluye diversos proce…
Libros y dinero: Valencia en el siglo XVIII
1990
Influence of a sterically hindered amine on the photo-oxidation of low density/linear low density polyethylene blends
1990
Abstract Low density/linear low density polyethylene blends show a rate of degradation of the mechanical properties during photo-oxidation which increases with the content of the linear polymer. The use of a sterically hindered amine as UV stabilizer greatly improves the resistance of these blends to UV irradiation. The effectiveness of the stabilizer increases with the content of linear low density polyethylene.
LVU zinātnisko rakstu krājumi, 1949-1989: bibliogrāfiskais rādītājs
1990
Bibliogrāfiskajā rādītājā ietverti P. Stučkas LVU izdotie Zinātnisko raktu krājumi laika no 1976.g.-1989.g., kā arī līdz 1976.g. izdotie krājumi, kuri dažādu iemeslu dēļ netika izdoti kā Zinātniskie raksti.
L'instrumentum
1990
A propos des économies de marché
1990
National audience
Las Cuevas del Puntal del Horno Ciego: Villagordo del Cabriel - Valencia
1990
Sanidics: A new class of mesophases, displayed by highly substituted rigid-rod polyesters and polyamides
1990
Abstract The structure of rigid-chain polyesters and polyamides which possess flexible side chains consisting of methylene or 1,4,7-trioxaoctyl oxide units have been investigated by means of X-ray scattering. The X-ray studies were performed on fibres and monodomains. Additional information was gained from calorimetric, dilatometric and microscopic studies. The investigations revealed that these polymers display mesophases and that the structures of the mesophases differ from those observed for discotic and calamitic phases. They are characterized by the fact that in the ordered and disordered phases board-like molecules are stacked parallel on top of each other and that these stacks of mol…
Brain Oedema and Intracranial Pressure in Superior Sagittal Sinus Balloon Occlusion. An Experimental Study in Pigs
1990
About 2/3 of all patients with thrombosis of the superior sagittal sinus (SSS) develop signs of increased ICP and/or brain oedema (BE). The time of onset and the spectrum of symptoms in SSS thrombosis vary extremely. This variability might be caused by differences in pathomechanism like BE and rise of ICP, parameters studied in the present contribution.
Possible Precision Far—Infrared Spectroscopy on Trapped Ions
1990
One of the necessary conditions for very high resolution spectroscopy is the existence of long-living energy levels between which transitions can be induced by tunable electromagnetic radiation. Moreover the observation time of the particles under investigation should be sufficiently long, and perturbing effects like Doppler broadening and collisions should be very small. All this leads to the technique of trapped ion spectroscopy which offers all the required conditions. It uses the confinement of charged particles to a very small volume in space under ultrahigh vacuum conditions either by application of a r.f. voltage and a small additional d.c. bias to an arrangement of three electrodes …
Vascular atherosclerotic disease: evaluation of the whole-blood filterability and red cell membrane microrheological pattern after intravenous admini…
1990
SummaryA study was carried out in 10 patients with vascular atherosclerotic disease to investigate the effects of a single dose of 300 mg pentoxifylline, given by intravenous infusion over 30 minutes, on various macrorheological and nzicrorheological parameters. Measurements were made at baseline, at the end of the intravenous infusion and again 30 minutes later of whole-blood filterability, erythrocyte membrane fluidity (using pyrene as probe) and transverse fluidity gradient (using fluorescent fatty acids as probes). The results showed that there was a significant variation in whole-blood filterability and the red cell membrane fluidity gradient after pentoxifylline. No difference, howeve…
A propósito del "Programa de ordenacion y promocion de agricultura de montaña" del Alto Mijares y Alto Palancia (Castellón)
1990
Cada vez es mayor el grado de concienciacion social y politico sobre la problematica de las zonas desfavorecidas en españa. En la comunidad valenciana, el programa de ordenacion y promocion del alto mijares y alto palancia es el primer documento aprobado oficialmente por el gobierno regional que, en el marco de la ley de agricultura de montaña, pretende constituirse en la base de las actuaciones tendentes a hacer frente a la dinamica reciente de estas zonas desfavorecidas. En este articulo se hace un analisis critico de algunas de las aportaciones mas destacables desde la optica de la geografia. (a)
El "Santo Tomás" de Velázquez del Museo Diocesano de Orihuela
1990
SE DOCUMENTA POR PRIMERA VEZ LA LLEGADA DE LA PINTURA DE "SANTO TOMAS", ATRIBUIDA A VELAZQUEZ, AL COLEGIO DE SANTO DOMINGO DE ORIHUELA (ALICANTE). GRACIAS A LOS DOCUMENTOS EN LOS QUE SE FECHA EL PAGO DEL BASTIDOR Y LA COLOCACION DEL LIENZO EN 1633, SE DESTACA LA FINALIZACION DE LA PINTURA. EN ESTA CRONOLOGIA SE INVESTIGA LA RELACION ENTRE EL COLEGIO Y LA CASA REAL, SIENDO LA OBRA REGALO DEL DOMINICO ANTONIO DE SOTOMAYOR, CONFESOR DEL REY, NOMBRADO PROTECTOR DEL COLEGIO EN 1631. ADEMAS, SE ANALIZA LA PINTURA Y SU HISTORIA DESDE SU LLEGADA AL COLEGIO HASTA LA ACTUALIDAD. (A.B.C./ L.A.G.)
Morphological Differences in Neuromasts of the Blind Cave Fish <i>Astyanax hubbsi </i>and the Sighted River Fish <i>Astyanax mexica…
1990
Vital staining and scanning electron microscopy were used to study the morphology of superficial neuromasts in the blind cave fish, Astyanax hubbsi, and its sighted congener, <i&