14,011 research outputs found
A covariant approach to the quantisation of a rigid body
No full textThis paper concerns the quantisation of a rigid body in the
framework of ``covariant quantum mechanics'' on a curved spacetime with absolute time. We consider the configuration space of classical particles as the -fold product of the configuration space of one particle. Then, we impose a rigid constraint and the resulting space is dealt
with as a configuration space of a single abstract `particle'.
This classical framework turns out to be suitable for the formulation of covariant quantum mechanics according to this scheme. Thus, we quantise such a `particle' accordingly.
This scheme can model, e.g., the quantum dynamics of
extremely cold molecules. We provide a new mathematical interpretation of two-valued wave functions on
in terms of single-valued sections of a new non-trivial quantum bundle. These results have clear analogies with spin
Micandra aegides C. Felder & R. Felder 1865
No full text<i>Micandra aegides</i> (C. Felder & R. Felder, 1865) <p> <i>Pseudolycaena aegides</i> C. Felder & R. Felder, 1865: 246, pl. 31: figs. 3, 4. <i>Thecla aegides</i> (C. Felder & R. Felder, 1865); Draudt 1919: 753, pl. 148h. <i>Thecla</i> (<i>Micandra</i>) <i>aegides</i> (C. Felder & R. Felder, 1865); D’Abrera 1995: 1130. <i>Egides aegides</i> (C. Felder & R. Felder, 1865); Johnson <i>et al.</i> 1997: 16. <i>Thecla amplitudo</i> Druce, 1907.</p> <p> <i>Egides amplitudo</i> (Druce, 1907); Johnson <i>et al.</i> 1997: 17.</p> <p> <i>Thecla aegides</i> f. <i>amplitudo</i> Druce; Draudt 1919: 753.</p> <p> <i>Micandra aegides</i> (C. Felder & R. Felder, 1865); Robbins 2004: 120.</p> <p> <b>Taxonomic history and remarks.</b> The species <i>Thecla amplitudo</i> (Druce) has was considered a form of <i>M. aegides</i> by Draudt (1919) and as a valid species by Johnson <i>et al.</i> (1997). I was unable to examine the holotype of <i>T. amplitudo</i>, thus I follow Robbins (2004). Clench (1971) suggested that <i>T. aegides</i> may be a member of <i>Micandra</i> based on its external appearance; Robbins (1986) confirmed this hypothesis based on the examination of genitalia and wing venation.</p> <p> <b>Diagnosis.</b> Males and females of this species may be confused with those of <i>M. stephanieae</i> described below (see diagnosis and description of that species).</p> <p> <b>Distribution.</b> This is the most widespread and common <i>Micandra</i> species in Colombia, recorded from the three Andean cordilleras at elevations between 2000 m and 3200 m.</p> <p> <b>Material examined. BOYACÁ:</b> 1 Ƥ JFLC: Villa de Leyva, 2000m, 28/iii/1994, Leg. J. F. Le Crom.</p> <p> <b>CAUCA:</b> 1 3 CP: Colombia, Cauca, Totoró, Cerro de La Horqueta, 2740m, 20/06/2009, Leg. C. Prieto, m1229; 2 3 CP*: Colombia, Cauca, Totoró, Cerro de La Horqueta, 2740m, 23/05/2009, Leg. C. Prieto, m1213, m1212; 2 3 CP: Colombia, Cauca, Totoró, Cerro de La Horqueta, 2740m, 02/06/2008, Leg. C. Prieto, m1181, m1179.</p> <p>1 Ƥ CP: Colombia, Cauca, Totoró, Cerro de La Horqueta, 2740m, 02/06/2008, Leg. C. Prieto, m1180; 1 Ƥ CP*: Colombia, Cauca, Argelia, Naranjal, 2900m, 23/07/06, Leg. C. Prieto, m815; 1 Ƥ CP: Colombia, Cauca, PNN Munchique, La Romelia, 2640m, 11/06/2001, Leg. C. Prieto, m017; 1 Ƥ CP: Colombia, Cauca, PNN Munchique, La Romelia, 2640 m, 17/09/2005, Leg. C. Prieto, m657; 1 Ƥ CP: Colombia, Cauca, S/der de Quilichao, Reserva Munchique –Los Tigres, 2450 m, 10/06/2009, Leg. C. Prieto, m1237.</p> <p> <b>CALDAS:</b> 1 3 JFLC: Caldas, Paramo de Letras, 2200 m, 09/xii/1990, Leg. J. Salazar.</p> <p> <b>CUNDINAMARCA:</b> 1 3 BMNH: Bogotá, Rotchild bequest; 1 3 JFLC: Mosquera, 2800 m, 23/iv/ 1985, Leg. J. F. Le Crom.</p> <p>1 Ƥ BMNH: Bogotá, (Child); 2 Ƥ CDV: Chicaque, montañas de Chicaque, 06/ marzo/ 1997, leg. D. Acosta; 1 Ƥ CDV: Bogotá, Monserrate, 04/enero/1991, Leg. D. Acosta; 1 Ƥ JFLC: Mosquera, 2/vii/ 1983, Leg. J. F. Le Crom; 1 Ƥ JFLC: Facatativa, 2800m, leg. J. F. Le Crom; 1 Ƥ JFLC: Bogotá, 19/xi/1989, leg. J. F. Le Crom; 1 Ƥ JFLC: Las Rosas, 17/xii/1989, Leg. J.F. Le Crom, 1 3 JFLC: Caldas, Paramo de Letras, 3000m, 04/viii/1993; 1 Ƥ JFLC: Páramo de Cruz Verde, 3200m, 09/xi/1998, Leg. J. F. Le Crom.</p> <p> <b>RISARALDA:</b> 2 Ƥ ICN-MHN: Risaralda, Pereira, Parque Ucumarí, La Pastora-Cedral, 2400m, Nov/24/1989, Leg. G. Andrade.</p> <p> <b>VALLE:</b> 2 3 CP: Colombia, Valle, PNN Farallones, Pico de Loro, 2800m, 02/05/2009, Leg. C. Prieto, m1185, m1186.</p> <p>1 Ƥ CP: Colombia, Valle, Cali, Cerro San Antonio, 2000m, 30/08/03, Leg. Prieto & Dahners, m075; 1 Ƥ CP: Colombia, Valle, Cali, Cerro San Antonio, 2200m, 14/09/03, Leg. Prieto & Dahners, m074; 1 Ƥ CP: Colombia, Valle, Cali, Cerro San Antonio, 2000m, 27/09/03, Leg. Prieto & Dahners, m123.</p>Published as part of <i>Prieto, Carlos, 2011, The genus Micandra Staudinger (Lepidoptera: Lycaenidae: Theclinae) in Colombia, with the description of a new species from the Sierra Nevada de Santa Marta, pp. 55-68 in Zootaxa 3040</i> on pages 60-61, DOI: <a href="http://zenodo.org/record/278794">10.5281/zenodo.278794</a>
Operating manual for the Marianda (Versatile INstrument for the Determination of Titration Alkalinity) VINDTA 3C for the laboratory based determination of Total Alkalinity and Total Dissolved Inorganic Carbon in seawater
No full textAll chemical and biogeochemical process in the sea are affected by the acidity of the water. Acidity is therefore fundamental property of seawater. The growing concern that the acidity of the oceans might be increasing has revealed weaknesses in our knowledge of this fundamental property and its variation in space and time. In 2008 the DEFRApH project (DEFRA contract ME4133) was initiated to provide this missing information in UK related waters. It required sampling for and analysis of the total inorganic carbon (DIC) and total alkalinity (TA) content of samples. This report documents the procedures used for operation of the VINDTA 3C analysis instrument (manufactured by Ludger Mintrop, Marianda, Kiel, Germany) developed at NOC since 2005. It covers instrument set up, daily procedures and the calculation of the final reported concentrations
Growth and characterization of high-T-c based heterostructures
No full textWe have investigated several trilayers based on the Bi2Sr2CaCu2O8+delta and YBa2Cu3O7+delta families. Our trilayers were realized using Bi2Sr2YCu2O8+delta and PrBa2Cu3O7-delta oxide barriers respectively with thicknesses ranging between 100 Angstrom and 300 Angstrom. The films have been grown on (001) SrTiO3 substrates by means of dc sputtering deposition in high pressure oxygen plasma. Electrical resistivity measurements showed T-c = 87 K and 91 K for the Bi2Sr2CaCu2O8+delta and YBa2Cu3O7-delta electrodes, respectively, and a semiconductor-like behavior of the Bi2Sr2YCu2O8+delta and PrBa2Cu3O7-delta nonconducting layers. In the case of Bi2Sr2CaCu2O8+delta/Bi2Sr2YCu2O8+delta/Bi2Sr2CaCu2O8+delta junctions, the tunneling dynamical conductance, G(V), at low temperatures, indicated gap-like structures at +/-30 mV. For the YBa2Cu3O7-delta/PrBa2Cu3O7-delta/YBa2Cu3O7-delta junctions, the G(V) showed gap features with very well defined maxima at +/-45 mV and a very low conductance at zero bias. We discuss both these behaviors in close comparison with the results obtained in high-T-c based tunnel structures with natural barriers
Humanismo en la concepción educativa de Luis Beltrán Prieto Figueroa | Humanism in the educational conception of Luis Beltrán Prieto Figueroa
No full textEl presente artículo, de naturaleza documental, estudia la concepción educativa del maestro y político venezolano Luis Beltrán Prieto Figueroa (1902-1993): el humanismo democrático. Se analiza lo que el humanismo es y la significación muy particular que le da Prieto Figueroa como conjunto de contenidos para la formación general e intelectual, de carácter teórico y libresco. También se analiza la dimensión política del humanismo democrático, cuyo sentido reside en la defensa y promoción de los principios democráticos y el trabajo productivo en beneficio de la comunidad, con descuido y menoscabo de la formación integral del educando. Palabras clave: Educación, escuela activa, política, formación integral. ABSTRACT The present article, of documentary nature, studies the educational conception of the Venezuelan teacher and politician Luis Beltrán Prieto Figueroa (1902-1993): the democratic humanism. It analyzes what humanism is and the very particular significance that Prieto Figueroa gives it as a set of contents for general and intellectual formation, theoretical and academic. The political dimension of democratic humanism is also analyzed, whose meaning lies in the defense and promotion of democratic principles and productive work for the benefit of the community, neglecting and impairing the integral formation of the student. Key words: Education, active school, politics, comprehensive education
Erinaceidae (Mammalia, Erinaceomorpha) from the Middle Miocene fissure filling Petersbuch 68 (southern Germany)
No full textEvolution, systematics and phylogeography of pleistocene horses in the new world: a molecular perspective
No full textThe rich fossil record of horses has made them a classic example of evolutionary processes. However, while the overall picture of equid evolution is well known, the details are surprisingly poorly understood, especially for the later Pliocene and Pleistocene, c. 3 million to 0.01 million years (Ma) ago, and nowhere more so than in the Americas. There is no consensus on the number of equid species or even the number of lineages that existed in these continents.Likewise, the origin of the endemic South American genus Hippidion is unresolved, as is the phylogenetic position of the “stilt-legged” horses of North America. Using ancient DNA sequences, we show that, in contrast to current models based on morphology and a recent genetic study, Hippidion was phylogenetically close to the caballine (true) horses, with origins considerably more recent than the currently accepted date of c. 10 Ma. Furthermore, we show that stilt-legged horses, commonly regarded as Old World migrants related to the hemionid asses of Asia, were in fact an endemic North American lineage. Finally, our data suggest that there were fewer horse species in late Pleistocene North America than have been named on morphological grounds. Both caballine and stilt-legged lineages may each have comprised a single, wide-ranging species.<br/
Contacte lingüístic i entonació a Sardenya. Contact, variation and change in Romance and beyond
No full textAbstract. Catalan has been spoken in the Sardinian city of l’Alguer (Alghero in Italian) ever since the city was conquered by the Crown of Aragon in 1354 and subsequently repopulated by Catalan-speakers from different areas. This Catalan koiné was later modified by Sardinian, both as a language of contact and as L1 of many immigrants to the city. This Catalan variety is also said to have been modified by standard Italian, especially from the second half of the 20th century. This paper is concerned with the effects that language contact between Algherese Catalan and Sardinian may have exerted on the intonational phonology of Algherese, as evidenced in recordings of the speech of 176 speakers (7 Algherese speakers, 9 Sardinian speakers and 160 Catalan speakers from outside l’Alguer). Data analysis shows that the seven nuclear configurations described for Sardinian are also found in Algherese and are associated with the same linguistic functions. However, half of these nuclear configurations are also present in the varieties of Catalan spoken outside l’Alguer. In addition, we note a pattern that seems to be specific to Algherese. This is the tonal configuration L+H* !H% used in the so-called vocative chant, in which the nuclear accent L+H* can be associated with the first syllable in disyllabic truncated vocatives (e.g., MaL+H*ri’!H%!, MiL+H*que’!H%!). This tonal association seems to suggest that the first syllable of the truncated vocative is the stressed syllable on the surface. These data show that Algherese, as a contact variety, has not only been influenced by neighbouring languages but is also undergoing language-internal changes
Exploring ICA for time series decomposition
No full textIn this paper, we apply independent component analysis (ICA) for prediction and signal extraction in multivariate time series data. We compare the performance of three different ICA procedures, JADE, SOBI, and FOTBI that estimate the components exploiting either the non-Gaussianity, or the temporal structure of the data, or combining both, non-Gaussianity as well as temporal dependence. Some Monte Carlo simulation experiments are carried out to investigate the performance of these algorithms in order to extract components such as trend, cycle, and seasonal components. Moreover, we empirically test the performance of those three ICA procedures on capturing the dynamic relationships among the industrial production index (IPI) time series of four European countries. We also compare the accuracy of the IPI time series forecasts using a few JADE, SOBI, and FOTBI components, at different time horizons. According to the results, FOTBI seems to be a good starting point for automatic time series signal extraction procedures, and it also provides quite accurate forecasts for the IPIs.ICA, Signal extraction, Multivariate time series, Forecasting
Enzyme activity of extracellular protein induced in Trichoderma asperellum and T. longibrachiatum by substrates based on Agaricus bisporus and Phymatotrichopsis omnivora
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