Morphology of phase separated blends of poly(cyclohexyl methacrylate) with poly(vinyl acetate)

Blends of poly(vinyl acetate) (PVAc) and poly(cyclohexyl methacrylate) (PCHMA) labeled by copolymerization with 4-methacryloylamine-4′-nitrostilbene (Sb), with (1-pyrenylmethyl)methacrylate (Py) or with 3-(methacryloylamine)propyl-N-carbazole (Cbz), were prepared by casting dilute solutions in tetrahydrofurane (THF) or chloroform onto silanized glass plates. The resulting films were studied by epifluorescence microscopy, microfluorescence spectroscopy, DSC and optical microscopy. Epifluorescence micrography probes the chemical composition of the different regions in phase separated blends, with black areas corresponding to PVAc rich regions and colored areas corresponding to labeled PCHMA rich regions. The technique also visualizes primary and secondary morphologies, which depend on the composition of the polymer blend and on the casting solvent. Mixtures containing 80 wt % PCHMA show, in general, a bicontinuous primary morphology suggesting a spinodal demixing mechanism. Solvent effects are particularly relevant for 50% and 20% PCHMA samples showing morphologies composed of PCHMA rich domains, in a matrix of solvent-dependent compositions. Samples cast from chloroform are more homogeneous and the matrix is always highly fluorescent. In contrast, the domains of samples cast from THF are heterogeneous in size and shape and the matrix is non-fluorescent, being thus formed by nearly pure PVAc. Small voids are formed in the polymer-air interface. They are submicrometric for THF cast films and disappear with annealing at 122°C. For chloroform cast samples they are much less frequent and appear well ordered, forming a mostly hexatic two dimensional network.This work was supported by DCI (Spain) and EU (Brite-Euram) under grants BQU2000-0251 and BE-97-4672, respectively

El grupu neandertal de la Cueva d' El Sidrón (Borines, Piloña)

El artículo está en la lengua asturianaPeer reviewe

El grupu neandertal de la Cueva d'El Sidrón (Borines, Piloña)

Na monografía clásica de Puig y Larraz (1896: 250-252) amiéntense delles cavidaes del Conceyu de Piloña, pero non la Cueva d’El Sidrón (Fig. 1). Esta conocíase, ensin dulda, dende la Guerra Civil y el maquis al servir d’abellugu a persiguíos políticos, y guarda una alcordanza imborrable nuna de les sos múltiples entraes, yá qu’ellí ta enterrada Olvido Otero González (1908-1938). Per El Sidrón pasaron munches persones a lo llargo de los años, pero en 1994 prodúxose’l descubrimientu per parte d’unos espeleólogos xixoneses d’unos güesos humanos que dieron un importante xiru a la conocencia de los nuesos antepasaos neandertales.Peer Reviewe

Prospecciones y excavaciones arqueológicas en el Alto Valle del Jarama (Valdesotos, Guadalajara, Castilla - La Mancha)

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El género es una máscara

Título tomado de la cub. En el interior : igualdad de oportunidades entre los sexos : coeducaciónPropuesta de trabajo sobre coeducación partiendo de la celebración de la fiesta del carnaval. Tiene como principal finalidad ofrecer al profesorado un instrumento de trabajo interdisciplinar que sensibilice a la comunidad educativa sobre la igualdad de oportunidades entre los sexos, superando los estereotipos y roles asimilados a la diferenciación por sexos y favoreciendo la socialización de los alumnos al margen del género..AragónBiblioteca de Educación del Ministerio de Educación, Cultura y Deporte; Calle San Agustín 5 -3 Planta; 28014 Madrid; Tel. +34917748000; [email protected]

The Atapuerca Sites and the Ibeas Hominids

ABSTRACT:The Atapuerca railway Trench and Ibeas sites near Burgos, Spain, are cave fillings that include a series of deposits, ranging from below the Matuyama/Bruhnes reversal up to the end of Middle Pleistocene. The lowest fossil-bearing bed in the Trench contains an assemblage of large and small Mammals including Mimomys savini, Pitymys gregaloides, Pliomys episcopalis, Crocuta crocuta, Dama sp, and Megacerini; the uppermost assemblage includes Canis lupus, Lynx spelaea, Panthera (Leo) fossilis, Felis sylvestris, Equus caballus steinheimensis, E. c. germanicus, Pitymys subterraneus. Microtus arvalis agrestis, Pliomys lenki, and also Panthera toscana, Dicerorhinus hemitoecbus, Bison schoetensacki, which are equally present in the lowest level. The biostratigraphic correlation and dates of the sites are briefly discussed, as are the paleoclimatic interpretation of the Trench sequences. Stone artifacts are found in several layers; the earliest occurrences correspond to the upper beds containing Mimomys savini. A set of preserved human occupation floors has been excavated in the top fossil-bearing beds. The stone-tool assemblages of the upper levels are of upper-medial Acheulean to Charentian tradition. The rich bone breccia SH, in the Cueva Mayor-Cueva del Silo, Ibeas de Juarros, is a derived deposit, due to a mud flow that dispersed and carried the skeletons of many carnivores and humans. The taxa represented are, Ursus deningeri (largely dominant), Panthera (Leo) fossilis, Vulpes vulpes, Homo sapiens var. Several traits of both mandibular and cranial remains are summarized. Preliminary attempts at dating suggest that the Ibeas fossil man, is older than the Last Interglacial, or Oxygen-isotope stage 5.RESUMEN: La Trinchera del ferrocarril de Atapuerca y yacimientos de Ibeas cerca de Burgos, España, son rellenos de cuevas que incluyen una serie de depósitos, que datan desde por debajo de la inversión Matuyama/Bruhnes hasta el final del Pleistoceno Medio. El nivel fosilífero de la Trinchera contiene un conjunto de grandes y pequeños Mamíferos incluyendo Mimomys savini, Pitymys gregaloides, Pliomys episcopalis, Crocuta Crocuta, Dama sp. y Megacerini; el conjunto más superior incluye Canis lupus, Lynx spelaea, Panthera (Leo) fossilis, Felis sylvestris, Equus caballus steinheimensis, E. c. germanicus, Pitymys subterraneus, Microtus arvalis agrestis, Pliomys lenki y también Panthera toscana, Dicerorhinus hemitoechus, Bison schoetensacki, que están igualmente presentes en el nivel más inferior. La correlación bioestratigráfica y las edades de los yacimientos se discuten brevemente, al igual que la interpretación paleoclimática de las secuencias de Trinchera. Los artefactos de piedra se encuentran en varios niveles, las primeras apariciones corresponden a los niveles superiores que contienen Mimomys savini. Se ha excavado un conjunto de suelos que preservan ocupación humana en la parte superior de los niveles fosilíferos. Los conjuntos de herramientas de piedra de los niveles superiores son del Achelense superior-medio a la tradición Charentiense. La rica brecha fosilífera SH, en la Cueva Mayor-Cueva del Silo, Ibeas de Juarros, es un depósito derivado, debido a un flujo de lodo que dispersó y transportó los esqueletos de muchos carnívoros y humanos. Los taxones representados son, Ursus deningeri (muy predominante), Panthera (Leo) fossilis, Vulpes vulpes, Homo sapiens var. Se resumen los rasgos de los restos mandibulares y craneales. Los intentos preliminares de datación sugieren que el hombre fósil de Ibeas, es más antiguo que el último Interglacial, o estadio de oxígeno isotópico 5.Peer reviewe

Clinical and treatment outcomes of a second subcutaneous or intravenous anti-TNF in patients with ulcerative colitis treated with two consecutive anti-TNF agents: data from the ENEIDA registry

Background: Infliximab seems to be the most efficacious of the three available anti-TNF agents for ulcerative colitis (UC) but little is known when it is used as the second anti-TNF. Objectives: To compare the clinical and treatment outcomes of a second subcutaneous or intravenous anti-TNF in UC patients. Design: Retrospective observational study. Methods: Patients from the ENEIDA registry treated consecutively with infliximab and a subcutaneous anti-TNF (or vice versa), naïve to other biological agents, were identified and grouped according to the administration route of the first anti-TNF into IVi (intravenous initially) or SCi (subcutaneous initially). Results: Overall, 473 UC patients were included (330 IVi and 143 SCi). Clinical response at week 14 was 42.7% and 48.3% in the IVi and SCi groups (non-statistically significant), respectively. Clinical remission rates at week 52 were 32.8% and 31.4% in the IVi and SCi groups (nonsignificant differences), respectively. A propensity-matched score analysis showed a higher clinical response rate at week 14 in the SCi group and higher treatment persistence in the IVi group. Regarding long-term outcomes, dose escalation and discontinuation due to the primary failure of the first anti-TNF and more severe disease activity at the beginning of the second anti-TNF were inversely associated with clinical remission. Conclusion: The use of a second anti-TNF for UC seems to be reasonable in terms of efficacy, although it is particularly reduced in the case of the primary failure of the first anti-TNF. Whether the second anti-TNF is infliximab or subcutaneous does not seem to affect efficacy