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On the edge of a World Heritage Site: local communities and archaeological practice related to the nomination of the New Caledonia Coral Reef

  • Sand, Christophe
The nomination of six portions of the New Caledonian coral reef as a natural World Heritage Site in 2009 has led, in his wake, to a profound change in archaeological practice in some parts of this multicultural archipelago of Southern Melanesia. This has especially been the case in the region of Bourail, where a large-scale economic development program was started to attract tourists to the reef, with the construction of hotels, an international 18 holes golf course and related infrastructures, all included in the immediate buffer zone of the site. The paper will present the changes witnessed in relation to heritage management as part of the overall development projects. Due to a community-riven demand, the Provincial Services in charge of heritage preservation, have agreed to the idea of the local stakeholders to impose a general archaeological survey of surface sites (abandoned villages, planting grounds, burial areas etc), followed by largescale rescue excavations before any construction. In total, over 300 sites have been documented to date in the 8000 hectares of the property. Over 13000 m2 of surfaces have been excavated, making this area the largest single excavation project ever done in Melanesia. The paper will focus on the specific agreements finalized with the indigenous Kanak groups, as part of the archaeological procedures, around the discovery and study of human remains, before summarizing the main results of the program. These have shown an unexpected number of landscape transformations during the last 3000 years, with the massive expansion of the seashore dune system as well as the intensified occupation of the inland areas over the last 700 years before first European contact. The presentation of the results to the public through site visits, films, exhibitions, on-site panels and publications, has allowed the collective appropriation of the archaeological discoveries by the inhabitants of the Bourail region and beyond, whatever their cultural origins.
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Los Museos del Acrópolis y la política patrimonial en Grecia

  • García González, Julia
Atenas, referente en la tutela del patrimonio arqueológico, ha sido objeto de análisis desde la disciplina arquitectónica debido a la construcción del Nuevo Museo del Acrópolis. En esta comunicación se examina la repercusión del nuevo museo a nivel patrimonial, social y urbano realizando una comparativa con el antiguo museo, sus características, modelo de gestión, surgimiento y la vinculación de éste con las áreas arqueológicas en las que se enclava; la situación actual de está interacción; las modificaciones con respecto al antiguo museo del Acrópolis. Por último se presentan una serie de proyectos, realizados posteriormente, como alternativa al museo ya construido.
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Acciones transversales y arqueología pública: propuestas para dos casos brasileños

  • Barbosa Frederico, Isabela
  • Vilhena de Moraes, Tobías
  • Soares Poloni, Rita Juliana
La presente propuesta viene al encuentro de las recientes discusiones en el área del turismo y de los estudios patrimoniales, en el ámbito brasileño y mundial, en lo que se refiere a la inclusión de la cultura como el cuarto eje del desarrollo sostenible. En esta perspectiva, el patrimonio deja de ser visto solamente como objeto de conservación o de exploración turística con fines económicos y empieza a ser interpretado a partir da la multivocalidad, o sea, de los diversos valores y agentes que circunscriben un determinado conjunto patrimonial y las comunidades locales. En este sentido, la arqueología pública surge como una práctica actuante en el sentido de contribuir para el desarrollo de interpretaciones que lleven en consideración las diferentes miradas acerca de la materialidad y que propicien un diálogo con las identidades locales. De esta forma, el término público utilizado aquí se relaciona no con las prácticas de gobiernos, sino que con las acciones en el ámbito comunitario. Los estudios de caso elegidos, ambos en territorio brasileño (“Missiones” – Patrimonio Mundial de la Unesco – en el estado del “Rio Grande do Sul” y el área protegida “Santuário do Caraça”, -Reserva de la Biosfera “Serra do Espinhaço” y de la “Mata Atlântica”, ubicada en el estado de Minas Gerais”), mantienen como punto en común el desarrollo de investigaciones y acciones comunitarias que enredan conocimiento patrimonial, desarrollo turístico sostenible e identidades locales. De esta forma, la autenticidad de los sitios emerge como resultados de las diferentes voces involucradas en la dinámica del patrimonio.
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Giant magnetic anisotropy at the nanoscale: Overcoming the superparamagnetic limit

  • Hernando Grande, Antonio
  • Crespo del Arco, Patricia
  • Garcia, M. A.
  • Fernández Pinel, E.
  • De la Venta,1, J
  • Fernández, A.
  • Penadés, S.
It has been observed for palladium and gold nanoparticles that the magnetic moment at a constant applied field does not change with temperature over the range comprised between 5 and 300 K. These samples, with sizes smaller than 2.5 nm, exhibit remanent magnetization up to room temperature. The existence of permanent magnetism up to so high temperatures has been explained as due to the blocking of a local magnetic moment by giant magnetic anisotropies. In this Brief Report we show, by analyzing the anisotropy of thiol capped gold films, that the orbital momentum induced at the surface conduction electrons is crucial to understand the observed giant anisotropy. The orbital motion is driven by a localized charge and/or spin through spin- orbit interaction, which reaches extremely high values at the surfaces. The induced orbital moment gives rise to an effective field of the order of 10(3) T that is responsible for the giant anisotropy.
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Funneling and guiding effects in ultrathin aSi-H solar cells using one-dimensional dielectric subwavelength gratings

  • Elshorbagy, Mahmoud Hamdy Mohamed
  • Alda, Javier
Ultrathin amorphous silicon hydrogenated (aSi-H) solar cells grown on a one-dimensional (1-D) dielectric subwavelength gratings improve the short circuit current by a factor of more than 51% when compared with conventional, flat ultrathin aSi-H devices. This improvement is possible due to several mechanisms. In addition the increase in exposed area caused by the nanostructured surface, a reliable computational electromagnetic evaluation of the interaction of the solar spectrum with the cell structure demonstrates that absorption at the active layer is enhanced and also reflectivity is decreased. In addition, the absorbed power at the nonactive layers is larger, helping to increase the temperature and mitigate the Staebler–Wronski effect. The detailed analysis of the power flux inside the structure has also shown that funneling and guiding mechanism are at play, increasing the optical path within the active layer that produces a better performance of the cell.
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Lactoferrin Levels in Tears are Increased by the Topical Application of Diadenosine Tetraphosphate

  • Loma Lozano, Patricia
  • Guzmán Aránguez, Ana Isabel
  • Pérez de Lara, María Jesús
  • Pintor, Jesús
Purpose: This study was undertaken to determine the effect of the topical application of diadenosine tetraphosphate on lactoferrin levels in rabbit tears. Methods: Diadenosine tetraphosphate was topically instilled in a single-dose, tear samples were collected by micropipette and lactoferrin was measured by Enzyme-Linked ImmunoSorbent Assay (ELISA). Results: The concentration of lactoferrin in rabbit tears was significantly increased 1 h after diadenosine tetraphosphate application, remaining elevated for 3 h more. This effect was blocked by P2 receptors antagonists. Conclusions: Topical application of diadenosine tetraphosphate stimulates the secretion of lactoferrin in rabbit tears through P2 receptor activation.
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Ocular Surface Temperature During Scleral Lens Wearing in Patients With Keratoconus

  • Carracedo Rodríguez, Juan Gonzalo
  • Wang, Zicheng
  • Serramito Blanco, María
  • Martín Gil, Alba
  • Carballo Álvarez, Jesús
  • Pintor, Jesús
Objective: To evaluate the ocular surface temperature using an infrared thermography camera before and after wearing scleral lens in patients with keratoconus and correlate these results with the tear production and stability. Methods: A pilot, experimental, short-term study has been performed. Twenty-six patients with keratoconus (36.95+/-8.95 years) participated voluntarily in the study. The sample was divided into two groups: patients with intrastromal corneal ring (KC-ICRS group) and patients without ICRS (KC group). Schirmer test, tear breakup time (TBUT), and ocular surface temperature in the conjunctiva, limbus, and cornea were evaluated before and after wearing a scleral lens. Results: The patients wore the scleral lenses from 6 to 9 hours with average of 7.59+/-0.73 hours. No significant changes in Schirmer test and TBUT were found for both groups. No temperature differences were found between the KC-ICRS and the KC groups for all zones evaluated. There was a slight, but statistically significant, increase in the inferior cornea, temporal limbus, and nasal conjunctival temperature for KC-ICRS group and temporal limbus temperature decreasing for the KC group after wearing scleral lens (P<0.05). The conjunctiva and limbus temperature was statistically higher than the central cornea for both groups before and after scleral lenses wearing (P<0.05), but no difference in the peripheral cornea was found. No statistically significant differences in the central corneal temperature were found between the groups after scleral lens wearing (P>0.05). Conclusion: Scleral contact lens seems not to modify the ocular surface temperature despite the presence of the tear film stagnation under the lens.
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The influence of rigid gas permeable lens wear on the concentrations of dinucleotides in tears and the effect on dry eye signs and symptoms in keratoconus

  • Carracedo Rodríguez, Juan Gonzalo
  • González-Méijome, José Manuel
  • Martín Gil, Alba
  • Carballo Álvarez, Jesús
  • Pintor, Jesús
Purpose: To evaluate the signs and symptoms of dry eye and dinucleotide secretion in tears of keratoconus patients (KC) and the potential effect of rigid gas permeable (RGP) contact lens wear. Methods: Twenty-three KC patients and forty control subjects were enrolled in this study. Signs of dry eye including tear volume, tear stability and corneal staining along with symptoms were assessed using the McMonnies questionnaire. Tears were collected using Schirmer strips, and dinucleotide concentrations in collected tears measured using high pressure liquid chromatography. Values obtained in KC and controls were compared. The effect of contact lens wear in KC was also assessed. Results: KC eyes showed a significantly lower tear volume compared to controls, shorter tear break up time (TBUT), higher corneal staining and higher McMonnies dry eye questionnaire scores (p < 0.05). When compared with non-wearers, KC contact lens wearers showed significantly higher symptoms, lower Schirmer and TBUT values (p < 0.05). Concentration of Ap4A (0.695 ± 0.304 μM vs. 0.185 ± 0.178 μM) and Ap5A (0.132 ± 0.128 μM vs. 0.045 ± 0.036 μM) were higher in KC compared to controls (p < 0.001) and only Ap4A was statistically higher in RGP wearers compared to non-wearers (0.794 ± 0.478 μM vs. 0.417 ± 0.313 μM) (p < 0.05). Conclusion: Signs and symptoms of dry eye as well as concentrations of Ap4A and Ap5A were markedly increased in KC patients compared to controls. Moreover, Ap4A and symptoms of dry eye were statistically higher in RGP wearers compared to non-wearers. This seems to indicate that factors such as RGP contact lens wear might exacerbate the clinical condition of dry eye.
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Differences in Dry Eye Questionnaire Symptoms in Two Different Modalities of Contact Lens Wear: Silicone-Hydrogel in Daily Wear Basis and Overnight Orthokeratology

  • García Porta, Nery
  • Rico del Viejo, Laura
  • Martín Gil, Alba
  • Carracedo Rodríguez, Juan Gonzalo
  • Pintor, Jesús
  • González-Méijome, José Manuel
Purpose. To compare the ocular surface symptoms and signs in an adult population of silicone-hydrogel (Si-Hy) contact lens (CL) wearers with another modality of CL wear, overnight orthokeratology (OK). Materials and Methods. This was a prospective and comparative study in which 31 myopic subjects were fitted with the same Si-Hy CL and 23 underwent OK treatment for 3 months. Dry eye questionnaire (DEQ) was filled in at the beginning of the study and then after 15 days, 1 month, and 3 months using each CL modality. The tear quality was evaluated with noninvasive tear break-up time. Tear production was measured with Schirmer test. Tear samples were collected with Schirmer strips being frozen to analyze the dinucleotide diadenosine tetraphosphate (Ap4A) concentration with High-Performance Liquid Chromatography (HPLC). Results. After refitting with ortho-k, a reduction in discomfort and dryness symptoms at the end of the day (, ) was observed. No significant changes were observed in Ap4A concentration in any group. Bulbar redness, limbal redness, and conjunctival staining increased significantly in the Si-Hy group (, Kruskal–Wallis test). Conclusion. Discomfort and dryness symptoms at the end of the day are lower in the OK CL group than in the Si-Hy CL group.
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