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[spa] Entre los días 22 y 24 de abril de 1993 se celebró en Braga y Guimaraes el III Congreso de la Asociación de Demografía Histórica, que reunió a cerca de 250 especialistas. Además de varias conferencias, se presentaron y debatieron 63 ponencias y comunicaciones, distribuidas en 5 sesiones temáticas: 1. Mujeres, trabajo y reproducción. 2. Reconstrucción de familias y otros métodos microanalíticos para la historia de las poblaciones: estado actual y perspectivas para el futuro. 3. De hijos ilegítimos a hijos naturales: exposición, ilegitimidad y concepciones extramatrimoniales (del siglo XVI hasta el presente). 4. Actitudes sociales y políticas de protección a la vida. 5. Familias y linajes. Subpoblaciones monacales y sus redes. Siglos X al XVIII., [eng] From the 22 to 24 of April 1993 the 3rd. Congress of Asociación de Demografía Histórica, wich met around 250 specialist, was held in Braga and Guimaraes. Besides several conferences, 63 rapports were both brought out and discussed and distributed in 5 subjects: 1. Women, work and reproduction. 2. Families reconstitution and others microanalytical methods for the population's history: present situation and future perspectives. 3. From 'illegitim' to 'natural' children: exposition, illegitimacy and extramarital conceptions (from 16th. century to the present) 4. Social and political actitudes concerning life protection. 5. Families and lineage. Monastic subpopulations and their networks. From 10th to 18th century., [fra] Entre les jours 22 et 24 d'Avril de 1993 on a celebrè en Braga et Guimaraes le III Congrès de l'Asociatión de Demografía Histórica, qui a réuni près de 250 specialistes. De plus de plusieurs conférences, on a presenté et on a discuté 63 rapports, distribués dans 5 séances thématiques. 1. Des femmes, travail et reproduction. 2. Reconstructions des families et des autres méthodes microanalytiques pour la histoire des populations: l'etat actuel e des perspectives pour le futur. 3. De fils illégitimes à des fils naturels: exposition, ilégitimité et des conceptions extramatrimoniales (du XVI siècle jusqu'à présent). 4. Attitudes sociaux et politiques de protection à la vie. 5. Des familles et des lignages. Supopulations monacales et sese réseaux. Siècles X au XVIII.

Fusion of Epstein-Barr virus (EBV) with Raji cells was measured after exposure of the virus to neutral or low pH, enzymatic modification of the viral spike glycoproteins, or chemical modification of the target membrane. The relief of octadecylrhodamine (R18) fluorescence self-quenching was used to monitor fusion. Fusion of EBV with Raji cells at pH 5.9 was significantly enhanced compared to that at neutral pH. Treatment of Raji cells with agents known to modify the surface net charge (trinitrobenzene sulfonic acid) totally prevented fusion at a neutral pH. Desialylation of EBV significantly reduced the extent of fusion with Raji cells. Our results demonstrate that EBV is rapidly internalized and then fuses with lymphoblastoid cells in the endocytic vesicles.

Relief of fluorescence self-quenching was used to monitor fusion (14) of Epstein Barr virus (EBV) with Raji cells after exposure of the virus to a variety of experimental conditions such as neutral or low pH, enzymatic modification of the viral spike glycoproteins, or inhibition of the protein kinase C (PKC) activity. Incubation of the virus at pH 5.9 prior to the binding to the cell membrane led to a significant enhancement of fusion with the plasma membrane. Treatment of Raji cells with an agent known to elevate the endosomal and lysosomal pH (lysosomotropic agent) (3, 12) partially prevented fusion at neutral pH. Desialylation of EBV significantly reduced the extent of fusion with Raji cells. Protein kinase C inhibitor reduced EBV fusion with Raji cells, while treatment with the tumor promotor and the PKC activator TPA caused an increase in the final extent of fusion. Our results suggest that EBV fuses with lymphoblastoid cells in the endocytic vesicles after being rapidly internalized and that protein kinase C is involved in the process of viral entry into cells.

El segle XX apareix filosoficament com un segle de gran dispersio i multiplicitat. Tanmatix, aquesta es pot reduir drasticament: irracionalisme, sociologia i filosofia social, logica i metodologia. Preocupacio per l'existencia i la vida dels homes, vinguda de la desconfianca en la racionalitat, la qual, pero (no en podem prescindir), ha buscat refugi en la ciencia i la tecnica. Es la filosofia de la ciencia. Abordada tradicionalment com a analisi logica de les teries cientifiques, unic saber rigoros, s'ha vist ella tambe abocada a un atzucac: al segle XX la mateixa ciencia ha esdevingut problematica (relativitat, fisica quantica; o Kuhn, Feyerabend). Es pot reduir la ciencia a mera tecnica? Oblidar l'intent per esbrinar que ens diuen les seves equacions sobre el mon i quedar-nos amb la seva aplicacio? Apostar per un pensament «feble»? La mateixa ciencia, i els mateixos cientifics (Hawking) semblen demanar al filosof quelcom mes. Sens dubte cal que el filosof vagi mes enlla de la mera logia i, en dialeg amb la ciencia, sense dogmatismes i sense complexos, fer de la filosofia de la ciencia una nova filosofia de la naturalesa. Cal, de totes totes, decidir-se a tornar a fer filosofia.

A faunistic comparison is made between the specific inventories of Opisthobranch assemblages in four groups of Mediterranean submarine caves; those of the Medes Is. (Catalan coast, N.E. Spain; Huelin & Ros, 1984), of the N.E. coast of Majorca (Balearic Is.; Ros & Gilt, in press), of the Sorrentine Peninsula (Gulf of Naples; Cattaneo, 1981, 1982) and of the Istrian Peninsula (N. Adriatic Sea; Starmuhlner, 1955, 1968). Two methods have been used in comparing these inventories: a similarity index (that of Jaccard) -to ascertain the faunistic affinity in terms of the Opisthobranch species found in more than one inventory-, and a simple index which assumes this affinity to be inversely related to the geographical distance between the respective cave groups. The two indices give similar results. Some considerations are offered on the significance of these and on the need for a greater availability of inventories to facilitate comparative studies.

Fourteen species of Opisthobranch molluscs are cited from the Gymnesian Is. (Majorca and Minorca); at least eleven of them are new citations for these poor-searched islands, and six for the Balearic archipelago. Most species are banal and well-known on the nearby mainland coasts, but Elysia timida, Phyllaplysia lafonti and Phyllidia pulitzeri constitute uncommon records.

A list is given of the littoral benthic Mollusca collected in the hard bottoms of the Medes Islands, between 0 and 50 m deep, from samples obtained by scuba diving. These came from a two-year survey of these islands, and were sampled along 18 submarine transections on open hard bottoms and from submarine caves: they were sampled through the peeling-off of the substrate enclosed by a 400 or 1,600 cm2 quadrat. Those species not found by the authors but previously signaled by others have been added to the list; the result is a total of 255 species, subspecies and varieties of mol•luscs, distributed as follows: 8 Polyplacophora, 2 Scaphopoda, 168 Gastropoda (129 Prosobranchia, 38 Opisthobranchia, 1 Pulmonata), 75 Bivalvia and 2 Cephalopoda. Nearly half of these species were not previously known from the Medes Islands zone, and eight of them are new records for the Catalan littoral. This is the first paper on a series dealing with the distribution and ecology of the Mollusca of Medes Islands.

El nostre desig a l'hora d'aportar uns suggeriments pràctics per a l'organització i la posta en marxa dels racons didàctics -com a proposta per a grups-classe de Parvulari i Cicle Inicial- és presentar una línia de treball útil per tal d'ajudar els infants a adquirir entre d'altres recursos, unes determinades pautes i hàbits de comportament i treball. No es tracta de voler oferir fórmules màgiques o esquemes inamovibles, sinó que el nostre objectiu s'ha centrat a fer un recull -a partir d'experiències actuals i efectives- que de forma indicativa pogués servir, parcialment o total, a d'altres educadors. Hem intentat d'il·lustrar els diferents racons de treball amb un llistat d'elements, objectius i recursos que pensem que poden suggerir-ne molts d'altres, i ben segur que més reeixits. Estem convençuts que perquè qualsevol sistema, o tècnica siguin positius, només cal que un bon mestre cregui en la seva efectivitat. Consegüentment, doncs, totes les nostres aportacions han de ser considerades simplement com a suggeriments , que altres educadors possiblement podran enriquir i millorar.