A comparative study of silver amalgam and compomer as retrograde filling materials in periapical surgery

Objective: A comparative study is made of the histological effects of silver amalgam versus compomer (Dyract®) 90 days after placement as retrograde filling materials in experimental animals. Method: Six Beagle dogs were used, with total pulpectomy and orthograde material filling followed by periapical surgery of the 6 upper and 6 lower incisors (for a total of 72 teeth). Thirty-six teeth corresponded to the right side and were filled with the control material (silver amalgam), while the 36 teeth on the left side were filled with the compomer study material (Dyract®). After three months the animals were sacrificed and the histological study was carried out, with evaluation of bone formation, inflammation, and the tissue in contact with the filler material. The results obtained were subjected to a descriptive and comparative statistical analysis (chi-square test). Results: The samples retrogradely filled with compomer showed significantly greater percentage inflammation (76.19% versus 26.66% in the control group). On the other hand, a large proportion of samples with root cement growth were found in the compomer group. Filler material expulsion was also significantly more common when compomer was used. Conclusions: the comparative study of the histological findings showed greater inflammation but also greater root cement growth in the compomer group versus the controls

Provision of supplementary materials in Library and Information Science scholarly journals

Purpose- This study seeks to analyse the policies of library and information science (LIS) journals regarding the publication of supplementary materials, the number of journals and articles that include this feature, the kind of supplementary materials published with regard to their function in the article, the formats employed and the access provided to readers. Design/methodology/approach- The study analysed the instructions for authors of LIS journals indexed in the ISI Journal Citation Reports, as well as the supplementary materials attached to the articles published in their 2011 online volumes. Findings- Large publishers are more likely to have a policy regarding the publication of supplementary materials, and policies are usually homogeneous across all the journals of a given publisher. Most policies state the acceptance of supplementary materials, and even journals without a policy also publish supplementary materials. The majority of supplementary materials provided in LIS articles are extended methodological explanations and additional results in the form of textual information in PDF or Word files. Some toll-access journals provide open access to any reader to these files. Originality/value- This study provides new insights into the characteristics of supplementary materials in LIS journals. The results may be used by journal publishers to establish a policy on the publication of supplementary materials and, more broadly, to develop data sharing initiatives in academic settings.

Educació per al desenvolupament i la cooperació: criteris de valoració dels materials didàctics

Els mitjans de comunicació ens atansen periòdicament notícies commovedores i ens sotraguegen amb imatges de fams, sequeres o misèria, les víctimes de les quals acostumen a viure al sud. També ens fan arribar els èxits més notables de l'economia i la tècnica: més producció, més vendes, més autopistes, millors avions. Tot això passa, preferentment, al nord.

Surface passivation of crystalline silicon by Cat-CVD amorphous and nanocrystalline thin silicon films

In this work, we study the electronic surface passivation of crystalline silicon with intrinsic thin silicon films deposited by Catalytic CVD. The contactless method used to determine the effective surface recombination velocity was the quasi-steady-state photoconductance technique. Hydrogenated amorphous and nanocrystalline silicon films were evaluated as passivating layers on n- and p-type float zone silicon wafers. The best results were obtained with amorphous silicon films, which allowed effective surface recombination velocities as low as 60 and 130 cms -1 on p- and n-type silicon, respectively. To our knowledge, these are the best results ever reported with intrinsic amorphous silicon films deposited by Catalytic CVD. The passivating properties of nanocrystalline silicon films strongly depended on the deposition conditions, especially on the filament temperature. Samples grown at lower filament temperatures (1600 °C) allowed effective surface recombination velocities of 450 and 600 cms -1 on n- and p-type silicon.

BS-SEM evaluation of the tisular interactions between cortical bone and calcium-phosphate covered titanium implants

The improvement of the reliability of the contact between the osseous tissues and the implant materials has been tested by recovering the metallic implants with ceramic materials, usually calcium phosphates. In our study, the calcium phosphate recovering layers were deposited by means of a pulsed-laser deposition technique. Our aim was to to evaluate the tissue interactions established between cortical bone and titanium implants covered by five different layers, ranging from amorphous calcium phosphate to crystalline hydroxyapatite, obtained by altering the parameters of the laser ablation process. The surgical protocol of the study consisted in the simultaneous implantation of the five types of implants in both the tibial dyaphisis of three Beagle dogs, sacrificed respectively one, two and three months after the last surgical procedures. After the sacrifice, the samples were submitted to a scheduled procedure of embedding in plastic polymers without prior decalcification, in order to perform the ultrastructural studies: scanning microscopy with secondary and backscattered electrons (BS-SEM). Our observations show that both in terms of the calcified tissues appearing as a response to the presence of the different coatings and of time of recovering, the implants coated with crystalline calcium phosphate layers by laser ablation present a better result than the amorphous-calcium-phosphate-coated implants. Moreover, the constant presence of chondroid tissue, related with the mechanical induction by forces applied on the recovering area, strongly suggests that the mechanisms implied in osteointegration are related to endomembranous, rather than endochondral ossification processes

BS-SEM evaluation of the tisular interactions between cortical bone and calcium-phosphate covered titanium implants

The improvement of the reliability of the contact between the osseous tissues and the implant materials has been tested by recovering the metallic implants with ceramic materials, usually calcium phosphates. In our study, the calcium phosphate recovering layers were deposited by means of a pulsed-laser deposition technique. Our aim was to to evaluate the tissue interactions established between cortical bone and titanium implants covered by five different layers, ranging from amorphous calcium phosphate to crystalline hydroxyapatite, obtained by altering the parameters of the laser ablation process. The surgical protocol of the study consisted in the simultaneous implantation of the five types of implants in both the tibial dyaphisis of three Beagle dogs, sacrificed respectively one, two and three months after the last surgical procedures. After the sacrifice, the samples were submitted to a scheduled procedure of embedding in plastic polymers without prior decalcification, in order to perform the ultrastructural studies: scanning microscopy with secondary and backscattered electrons (BS-SEM). Our observations show that both in terms of the calcified tissues appearing as a response to the presence of the different coatings and of time of recovering, the implants coated with crystalline calcium phosphate layers by laser ablation present a better result than the amorphous-calcium-phosphate-coated implants. Moreover, the constant presence of chondroid tissue, related with the mechanical induction by forces applied on the recovering area, strongly suggests that the mechanisms implied in osteointegration are related to endomembranous, rather than endochondral ossification processes

BS-SEM evaluation of the tisular interactions between cortical bone and calcium-phosphate covered titanium implants

The improvement of the reliability of the contact between the osseous tissues and the implant materials has been tested by recovering the metallic implants with ceramic materials, usually calcium phosphates. In our study, the calcium phosphate recovering layers were deposited by means of a pulsed-laser deposition technique. Our aim was to to evaluate the tissue interactions established between cortical bone and titanium implants covered by five different layers, ranging from amorphous calcium phosphate to crystalline hydroxyapatite, obtained by altering the parameters of the laser ablation process. The surgical protocol of the study consisted in the simultaneous implantation of the five types of implants in both the tibial dyaphisis of three Beagle dogs, sacrificed respectively one, two and three months after the last surgical procedures. After the sacrifice, the samples were submitted to a scheduled procedure of embedding in plastic polymers without prior decalcification, in order to perform the ultrastructural studies: scanning microscopy with secondary and backscattered electrons (BS-SEM). Our observations show that both in terms of the calcified tissues appearing as a response to the presence of the different coatings and of time of recovering, the implants coated with crystalline calcium phosphate layers by laser ablation present a better result than the amorphous-calcium-phosphate-coated implants. Moreover, the constant presence of chondroid tissue, related with the mechanical induction by forces applied on the recovering area, strongly suggests that the mechanisms implied in osteointegration are related to endomembranous, rather than endochondral ossification processes

Amorphous silicon thin film solar cells deposited entirely by Hot-Wire Chemical Vapour Deposition at low temperature (<150 ºC)

Amorphous silicon n-i-p solar cells have been fabricated entirely by Hot-Wire Chemical Vapour Deposition (HW-CVD) at low process temperature < 150 °C. A textured-Ag/ZnO back reflector deposited on Corning 1737F by rf magnetron sputtering was used as the substrate. Doped layers with very good conductivity and a very less defective intrinsic a-Si:H layer were used for the cell fabrication. A double n-layer (μc-Si:H/a-Si:H) and μc-Si:H p-layer were used for the cell. In this paper, we report the characterization of these layers and the integration of these layers in a solar cell fabricated at low temperature. An initial efficiency of 4.62% has been achieved for the n-i-p cell deposited at temperatures below 150 °C over glass/Ag/ZnO textured back reflector.

Sintesi i caracteritzacio dels materials multiferroics BiFeO3, La: BiFeO3 i Sr: BiFeO3

Recentment, ha crescut un notable interès pels materials multiferroics (o materials que presenten simultàniament propietats elèctriques i magnètiques), a causa de les seves múltiples aplicacions, sobretot en el camp de l"electrònica. Aquest article pretén donar a conèixer els materials multiferroics, tant des del punt de vista de la física fonamental com de la química de l"estat sòlid. Tanmateix, es presentarà un dels materials multiferroics actualment més estudiats i s"exposaran els detalls de la seva síntesi i caracterització habituals en la química de l"estat sòlid.

Els materials arqueològics del jaciment ibèric de la Serra de l'Espasa (Capçanes, Priorat) dipositats al Museu d'Arqueologia Salvador Vilaseca de Reus: evidències d'un santuari?

En aquest treball presentem una revisió del jaciment ibèric de la Serra de l"Espasa (Capçanes, Priorat) a partir de l"estudi, amb criteris actualitzats, del material conservat en el Museu Salvador Vilaseca de Reus. Els resultats són contrastats amb les darreres investigacions arqueològiques desenvolupades en el curs inferior de l"Ebre. A l"últim, s"analitzen les possibles interpretacions d"aquest conjunt, en particular la hipotètica existència d"un santuari, i les seves implicacions en el procés de romanització en aquesta zona

Les pintures murals de la basílica paleocristiana de «Es Cap des Port» (Fornells, Menorca): materials i tècniques

[cat]El present treball ofereix una revisió de les pintures murals de la basílica de «Es Cap des Port» (Fornells, Menorca), així com un estudi de caracterització arqueomètrica deIs materials i tècniques per microscòpia òptica, tant amb lupa binocular com amb microscopi petrogràfic mitjançant làmina prima, difracció de raigs X i microscòpia electrònica de rastreig. Els resultats han permès identificar els pigments emprats, així com la seva tècnica d'aplicació. Igualment, han permès caracteritzar els morters i han desvelat l' existència de dos tipus diferents de suport. Malgrat aquestes diferències en els morters, els pigments són sempre els mateixos per a tots els conjunts pictòrics caracteritzats [eng] The present paper offers a revision of the wall paintings found at the early Christian church of 'Es Cap des Port' (Fornells, Menorca). Moreover, the materials and techniques employed have been archaeometrically studied by means of optical microscopy, both with steromicroscope and petrographic microscope by thin section, X-ray diffraction and scanning electron microscopy. The results enable to identify the pigments used, as well as the techniques of application. It has also been possible to characterize the mortars, revealing the existence of two different types of support. In spite of these differences in the mortars, the pigments used are the same ones for all the studied wall paintings

Els materials arqueològics del jaciment ibèric del Coll del Moro de Serra d'Almos (Tivissa, Ribera d'Ebre). Col·lecció del Museu Comarcal Salvador Vilaseca de Reus

Presentem en aquest treball una revalorització d' aquestjaciment a partir de I'estudi amb criteris actualitzats del material conservat en el Museu Salvador Vilaseca de Reus. Els resultats són contrastats amb les darreres investigacions arqueologiques desenvolupades en el curs inferior de I'Ebre. Per últim, s'analitzen les possibles interpretacions d'aquest conjunt, i les seves implicacions en els inicis de la iberització en aquesta zona.

Èquids i gossos en l"economia i en els rituals. Resultats de l"estudi dels materials dipositats en el sitjar iberoromà del Serrat dels Espinyers (Isona, Pallars Jussà)

[cat]El Serrat dels Espinyers constitueix, per si mateix, un punt important en el poc conegut poblament ibéric del Pallars. En el panorama arqueològic català esdevé un cas únic pel que fa a la utiliztzació dels animals en activitats rituals vinculades tant a espais funeraris com domèstics, en particular pel volum i la qualitat de les dades aportades. L'anàlisi de les restes òssies animals i d'altes materials associats han procurart un conjunt de dades que permeten establir hipòtesis sobre els comportaments rituals de la societat ibèrica que va ocupar el jaciment. D'altra banda, es posa en evidència la importància de dos tàxons: els èquids i els gossos, i la seva relació amb l'activitat econòmica que hi va poder tenir lloc. [eng]Serrat dels Espinyers is an important site within the little known Iberian culture settlement of the Pallars area in Catalonia. Regarding the use of animals in ritual activities related to both domestic and funerary spaces, the data provided by this site are unique within the Catalan archaeology. The results obtained in the analysis of animal bones and other associated materials have allowed us to establish new hypotheses about the ritual behavior in Iberian society. Moreover, the importance of two taxa: horses and dogs, has been highlighted, as well as their relationship with the economic activity that could have taken place on the site.

L'ús de materials compostos en el reforç intern d'estructures de formigó

L’ús de materials compostos de matriu polimèrica (FRP, Fibre Reinforced Polymer) en el reforç intern d'estructures de formigó