Delayed-Choice Experiments and the Metaphysics of Entanglement

Delayed-choice experiments in quantum mechanics are often taken to undermine a realistic interpretation of the quantum state. More specifically, Healey has recently argued that the phenomenon of delayed-choice entanglement swapping is incompatible with the view that entanglement is a physical relation between quantum systems. This paper argues against these claims. It first reviews two paradigmatic delayed-choice experiments and analyzes their metaphysical implications. It then applies the results of this analysis to the case of entanglement swapping, showing that such experiments pose no threat to realism about entanglement.

Functionality of the plastron in adults of Neochetina eichhorniae Warner (Coleoptera, Curculionidae): aspects of the integument coating and submersion laboratory experiments

The plastron theory was tested in adults of Neochetina eichhorniae Warner, 1970, through the analysis of the structure that coats these insects' integument and also through submersion laboratorial experiments. The tegument processes were recognized in three types: agglutinated scales with large perforations, plumose scales of varied sizes and shapes, and hairs. The experiments were carried out on 264 adult individuals which were kept submerged at different time intervals (n = 11) and in two types of treatment, natural non-aerated water and previously boiled water, with four repetitions for each treatment. The tests showed a maximum mortality after 24 hours of immersion in the previously boiled water treatment. The survival of the adults was negative and significantly correlated with the types of treatment employed and within the different time intervals. The values of oxygen dissolved in water (mg/l) differed significantly within the types of treatment employed. They were positively correlated with the survival of the adults in the two types of treatment, although more markedly in the treatment with previously boiled water. The mortality of adults after 24 hours of submersion in the treatment with previously boiled water may be associated with the physical-chemical conditions of the non-tested water in this study, such as low surface tension and concentration of solutes. These results suggest plastron functionality in the adults of this species.

Experiments on substratum roughness, grainsize and volume influence on the motion and spreading of rock avalanches

The main objective of the research is to link granular physics with the modelling of rock avalanches. Laboratory experiments consist to find a convenient granular material, i.e. grainsize and physical behaviour, and testing it on simple slope geometry. When the appropriate sliding material is selected, we attempted to model the debris avalanche and the spreading on a slope with different substratum to understand the relationship between the volume and the reach angle, i.e. angle of the line joining the top of the scar and the end of the deposit. For a better understanding of the mass spreading, the deposits are scanned with a laser scanner. Datasets are compared to see how the grain size and volume influence a debris avalanche. The relationship between the roughness and grainsize of the substratum shows that the spreading of the sliding mass is increased when the roughness of the substratum starts to be equivalent or greater than the grainsize of the flowing mass. The runout distance displays a more complex relationship, because a long runout distance implies that grains are less spread. This means that if the substratum is too rough the distance diminishes, as well if it is too smooth because the effect on the apparent friction decreases. Up to now our findings do not permit to validate any previous model (Melosh, 1987; Bagnold 1956).

La Irresolubilitat dels problemes clàssics grecs : recurs didàctic per l'ensenyament i l'aprenentatge

La temàtica proposada consisteix en considerar els tres problemes clàssics grecs sense solució amb regla i compàs: la trisecció de l’angle, la quadratura del cercle i la duplicitat del cub per plantejar diverses activitats per realitzar a l’aula. Aquestes propostes didàctiques podran ser utilitzades per a la pràctica professional, amb les que es podran treballar molts conceptes matemàtics per abastar diferents nivells de coneixements, i mitjançant recursos i eines tradicionals i d’altres innovadors, així com aprofitant l’estudi de la història de les matemàtiques.

Anàlisi i adaptació de la gestió universitària de la Facultat de Nàutica de Barcelona als reptes de futur de l'Espai Europeu d'Ensenyament Superior

Treball elaborat per a la presentació al concurs oposició per a l’accés al’escalat tècnica de Gestió. Universitat Politècnica de Catalunya(Resolució 2991/2006 de 20 de desembre)

Tractament del reflux vesicoureteral primari pediàtric

Els nous conceptes sobre el paper del reflux en la patologia renal han posat en controvèrsia el tractament del RVU. Amb aquest treball es vol valorar la necessitat real del tractament quirúrgic i els seus avantatges. Després de realitzar una revisió retrospectiva dels pacients amb RVU que han rebut tractament quirúrgic entre el 2003 i 2007 s’ha vist que el tractament quirúrgic del RVU és efectiu amb una baixa taxa de complicacions. En casos seleccionats el tractament quirúrgic pot tindre un paper fonamental per la prevenció de lesió renal recomanant com a primera elecció el tractament endoscòpic .

Programming and analysing measurement experiments using the PicoCricket system

The aim of this project is to get used to another kind of programming. Since now, I used very complex programming languages to develop applications or even to program microcontrollers, but PicoCricket system is the evidence that we don’t need so complex development tools to get functional devices. PicoCricket system is the clear example of simple programming to make devices work the way we programmed it. There’s an easy but effective way to program small, devices just saying what we want them to do. We cannot do complex algorithms and mathematical operations but we can program them in a short time. Nowadays, the easier and faster we produce, the more we earn. So the tendency is to develop fast, cheap and easy, and PicoCricket system can do it.

Crocidura cossyrensis Contoli, 1989 (Mammalia, Soridiae): karyotype, biochemical genetics and hybridization experiments

Crocidura cossyrensis Contoli, 1989 (Mammalia, Soricidae): karyotype, biochemical genetics and hybridization experiments. - The shrew Crocidura cossyrensis Contoli, 1989 from Pantelleria (I), a Mediterranean island 100 km south of Sicily and 70 km west from Tunisia, was investigated in order to understand its origin and its relationship with C. russula from Tunisia, Morocco and Switzerland. With the exception of a single heterozygote centric fusion, C. cossyrensis had a karyotype identical with that of C russula from Tunisia (2N = 42, NF = 70 to 72), but it differed from C russula from Morocco and Switzerland (2N = 42, NF = 60). The former have 5-6 pairs of chromosomes with small arms that are acrocentric in the latter. Genetic comparisons with allozyme data revealed small genetic distance (0.04) between C cossyrensis and C russula from Tunisia. In contrast, this eastern clade (Tunisia and Pantelleria) is separated from the western clade (Switzerland and Morocco) by a genetic distance of 0.14. A hybridization experiment between shrews from Pantelleria and Switzerland lead rapidly to an F1 generation. From 12 F1 hybrids that were backcrossed, females reproduced normally, but none of the males did so. Concluding from the results, C. cossyrensis from Pantelleria and C. russula cf. agilis from Tunisia belong to the same taxon that may have reached the differentiation of a biological species within the C. russula group. More geographic samples are needed to determine the definitive taxonomic positions of these shrews.

L'ensenyament de la Biblioteconomia a Barcelona: de l'Escola a la Facultat de Biblioteconomia i Documentació

L'objectiu d'aquestes pàgines és reflectir l'evolució que ha seguit l'ensenyament de Biblioteconomia a l'Escola Superior de Bibliotecàries de Barcelona des de la seva creació el 1915 fins a l'actual Facultat de Biblioteconomia i Documentació de la Universitat de Barcelona.

Informe de les Primeres Jornades Ensenyament-Arxius "Didàctica amb fonts d'arxiu" (Barcelona, 5-7 de setembre de 2002)

El passat mes de setembre se celebraren a Barcelona les Primeres Jornades Ensenyament-Arxius que, amb el títol "Didàctica amb fonts d'arxiu", naixien de l'interès d'un grup de professionals del món dels arxius i de l'educació per fomentar la comunicació i la reflexió entre arxivers i docents, conscients de les potencialitats didàctiques de l'arxiu i els seus fons.

A software to calculate soil hydraulic conductivity in internal drainage experiments (SHC, Version 2.00)

A software for the calculation of unsaturated soil hydraulic conductivity K(theta) is presented for commonly used methods found in the literature, based on field experiments in which a soil profile is submitted to water infiltration followed by internal drainage. The software is available at: dourado@esalq.usp.br.

Recursos electrònics i audiovisuals per l'ensenyament i aprenentatge de la flauta dolça

Descripció i anàlisi dels principals webs dedicats a l'ensenyament-aprenentatge de la flauta de bec

L'ensenyament de la problemàtica del disseny en la pregunta pels seus orígens

A l'ensenyament dels fonaments històrics del disseny no és oportú assenyalar cap criteri teòric com si fos obvi i natural. La formació històrica dels criteris que pretenen legitimar-lo és fonamental per la comprensió del mateix disseny i per a la comprensió de la tensió teòrica que el fonamenta.