136 research outputs found

    Bio-inspired hydrogel composed of hyaluronic acid and alginate as a potential bioink for 3D bioprinting of articular cartilage engineering constructs

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    Bioprinting is a promising tool to fabricate well-organized cell-laden constructs for repair and regener- ation of articular cartilage. The selection of a suitable bioink, in terms of composition and mechanical properties, is crucial for the development of viable cartilage substitutes. In this study, we focused on the use of one of the main cartilage components, hyaluronic acid (HA), to design and formulate a new bioink for cartilage tissue 3D bioprinting. Major characteristics required for this application such as printabil- ity, biocompatibility, and biodegradability were analyzed. To produce cartilage constructs with optimal mechanical properties, HA-based bioink was co-printed with polylactic acid (PLA). HA-based bioink was found to improve cell functionality by an increase in the expression of chondrogenic gene markers and specific matrix deposition and, therefore, tissue formation. These results indicate that it is a promising bioink candidate for cartilage tissue engineering based in 3D bioprinting.This work was partially supported by MINECO MAT2016-78778-R and PCIN-2015-051 projects (Spain), European Regional Development Fund (ERDF), by the Consejería de Economía, Conocimiento, Empresas y Universidad de la Junta de Andalucía and European Regional Development Fund (ERDF), ref. SOMM17/6109/UGR and by the Ministerio de Economía, Industria y Competitividad ( FEDER funds, project RTC-2016-5451-1 ) (to JA.M and P.G-M)

    De la gran urbe a la modesta villa: aplicación de la prospección magnética a la arqueología romana

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    La caracterización de yacimientos arqueológicos es una de las aplicaciones más extendidas de la prospección magnética, por su carácter no invasivo, que permite explorar sin destruir superficies de extensión considerable, y debido al carácter ferromagnético de muchos elementos asociados a la actividad humana (instrumentos de hierro, componentes minerales de tejas, ladrillos, hornos de cocción, etc...). Habitualmente, en prospección magnética se mide la intensidad total del campo magnético terrestre (realizando las correcciones de las oscilaciones debidas a la variación diurna y las micropulsaciones) y el gradiente horizontal o vertical (diferencia entre las medidas tomadas simultáneamente en posiciones cercanas mediante dos sensores, ver figura 1), que resulta muy útil cuando se trata de detectar anomalías debidas a cuerpos cercanos a la superficie. Frente a la sistemática de trabajo en prospecciones geológicas, el mallado de la prospección magnética en arqueología suele ser muy denso, con 1 m o 0,5 m de espaciado entre perfiles en muchas ocasiones

    Dengue Vaccines Regulatory Pathways: A Report on Two Meetings with Regulators of Developing Countries

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    Richard Mahoney and colleagues summarize two recent meetings convened by the Pediatric Dengue Vaccine Initiative and the Developing Countries' Vaccine Regulators Network on regulatory issues that need to be addressed before licensing dengue vaccines

    Modeling Ecosystems Using P Systems: The Bearded Vulture, a Case Study

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    The Bearded Vulture (Gypaetus barbatus) is an endangered species in Europe that feeds almost exclusively on bone remains of wild and domestic ungulates. In this paper, we present a model of an ecosystem related to the Bearded Vulture in the Pyrenees (NE Spain), by using P systems. The evolution of six species is studied: the Bearded Vulture and five subfamilies of domestic and wild ungulates upon which the vulture feeds. P systems provide a high level computational modeling framework which integrates the structural and dynamic aspects of ecosystems in a comprehensive and relevant way. P systems explicitly represent the discrete character of the components of an ecosystem by using rewriting rules on multisets of objects which represent individuals of the population and bones. The inherent stochasticity and uncertainty in ecosystems is captured by using probabilistic strategies. In order to experimentally validate the P system designed, we have constructed a simulator that allows us to analyze the evolution of the ecosystem under different initial conditions.Ministerio de Educación y Ciencia TIN2006-13425Junta de Andalucía TIC-58

    Orphan crops of archaeology-based crop history research

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    So-called ‘forgotten’ or ‘orphan’ crops are an important component of strategies aimed at preserving and promoting biodiversity. Knowledge of historical cultivation, usage, and geographic and evolutionary trajectories of plants, that is, crop history research, is important for the long-term success of such efforts. However, research biases in the crops chosen for study may present hurdles. This review attempts to systematically identify patterns in crop species representativeness within archaeology-based crop history research. A meta-analysis and synthesis of archaeo- botanical evidence (and lack thereof) is presented for 268 species known to have been cultivated for food prior to 1492 CE from the Mediterranean region to South Asia. We identified 39 genera with known crop plants in this geographical and histor- ical context that are currently absent from its archaeobotanical record, constituting ‘orphan’ crops of archaeobotany. In addition, a worldwide synthesis of crop species studied using geometric morphometric, archaeogenetic and stable isotope analyses of archaeological plant remains is presented, and biases in the species represented in these disciplines are discussed. Both disciplinary methodological biases and economic agenda-based biases affecting species representativeness in crop history research are apparent. This study also highlights the limited geographic diffusion of most crops and the potential for deeper historical perspectives on how crops become marginal- ized and ‘forgotten’

    Campaniforme no funerario en la provincia de Toledo: el yacimiento de Las Vegas. De nuevo el Valle de Huecas

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    This article presents the latest results of the excavations at the site of Las Vegas in Huecas (Toledo). The site is located in an open area, near a stream and at the foot of the Valle de las Higueras necropolis. It is buried by a considerable colluvial deposition and was detected by geophysical survey. The site lacks structures and is made up of a single archaeological layer: it is a secondary deposit, containing Bell Beaker pottery and metal. A 14C sample has dated it to the second half of the 3rd millennium BC. Ceramics are the most abundant remain from this deposit. Macroscopic and X-ray Fluorescence (FRX) analysis of the ceramics indicates a local production, the fast formation of this deposit, and its long-term exposure on the surface. We suggest that it was formed by cleaning and maintenance activities carried out in a nearby occupational area. We suggest that settlement occurred in the valley bottom, with occupations whose ceramic productions differ from the ones found in funerary contexts.Presentamos los resultados de los sondeos del yacimiento de Las Vegas, Huecas (Toledo). Se trata de un área abierta, junto al arroyo y al pie de la necrópolis de Valle de las Higueras. Un fuerte depósito de coluvión sepulta el yacimiento. Sin evidencias en superficie, su detección se realizó mediante prospección geofísica. Carece de estructuras y está formado por un único estrato, un depósito secundario que contiene campaniforme Ciempozuelos y metal, con una fecha C14 de la 2ª mitad del III milenio a.C. La cerámica es el material más abundante. Su estudio macroscópico y mediante fluorescencia de rayos X (FRX) avala su producción local, la rápida formación del depósito y su larga exposición en superficie. Planteamos que el depósito procede de la limpieza y mantenimiento de un área de ocupación anexa. El patrón de poblamiento parece seguir las tierras bajas del valle con ocupaciones cuyas producciones cerámicas difieren de las de los contextos funerarios

    Human immunodeficiency virus/hepatits C virus coinfection in Spain: Elimination is feasible, but the burden of residual cirrhosis will be significant

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    Background We assessed the prevalence of antibodies against hepatitis C virus (HCV-Abs) and active HCV infection in patients infected with human immunodeficiency virus (HIV) in Spain in 2016 and compared the results with those of similar studies performed in 2002, 2009, and 2015. Methods The study was performed in 43 centers during October-November 2016. The sample was estimated for an accuracy of 2% and selected by proportional allocation and simple random sampling. During 2016, criteria for therapy based on direct-acting antiviral agents (DAA) were at least significant liver fibrosis, severe extrahepatic manifestations of HCV, and high risk of HCV transmissibility. Results The reference population and the sample size were 38904 and 1588 patients, respectively. The prevalence of HCV-Abs in 2002, 2009, 2015, and 2016 was 60.8%, 50.2%, 37.7%, and 34.6%, respectively (P trend <.001, from 2002 to 2015). The prevalence of active HCV in 2002, 2009, 2015, and 2016 was 54.0%, 34.0%, 22.1%, and 11.7%, respectively (P trend <.001). The anti-HCV treatment uptake in 2002, 2009, 2015, and 2016 was 23.0%, 48.0%, 59.3%, and 74.7%, respectively (P trend <.001). In 2016, HCV-related cirrhosis was present in 7.6% of all HIV-infected individuals, 15.0% of patients with active HCV, and 31.5% of patients who cleared HCV after anti-HCV therapy. Conclusions Our findings suggest that with universal access to DAA-based therapy and continued efforts in prevention and screening, it will be possible to eliminate active HCV among HIV-infected individuals in Spain in the short term. However, the burden of HCV-related cirrhosis will continue to be significant among HIV-infected individuals

    New evidence of factor structure and measurement invariance of the SDQ across five European nations

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    The main purpose of the present study was to test the internal structure and to study the measurement invariance of the Strength and Difficulties Questionnaire (SDQ), self-reported version, in five European countries. The sample consisted of 3012 adolescents aged between 12 and 17 years (M = 14.20; SD = 0.83). The five-factor model (with correlated errors added), and the five-factor model (with correlated errors added) with the reverse-worded items allowed to cross-load on the Prosocial subscale, displayed adequate goodness of-fit indices. Multi-group confirmatory factor analysis showed that the five-factor model had partial strong measurement invariance by countries. A total of 11 of the 25 items were non-invariant across samples. The level of internal consistency of the Total difficulties scores was .84, ranging between .69 and .78 for the SDQ subscales. The findings indicate that the SDQ's scales need to be modified in various ways for screening emotional and behavioural problems in the five European countries that were analyzed

    Middle Neolithic farming of open-air sites in SE France: new insights from archaeobotanical investigations of three wells found at Les Bagnoles (L'Isle-sur-la-Sorgue, Dépt. Vaucluse, France)

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    Previous reviews of Middle Neolithic agricultural practice (4400–3500 cal bc) in southern France have highlighted a change in crop assemblages after 4000 cal bc, with a reduction of naked wheat and an increase of emmer and partly of einkorn. The recent investigation of three wells from the site of Les Bagnoles (4250–3800 cal bc) in the periphery of the southern Rhône valley yielded an unprecedented amount of waterlogged uncharred and charred plant macro remains that offer new insights into crop diversity and its changes over time. The results from the wells at Les Bagnoles were compared with other dated sunken features from open-air sites (in contrast to caves and rock shelters), with the aim of identifying patterns sug-gesting changes in the crop spectra between the early (MN1) and late (MN2) Middle Neolithic phases from taphonomically comparable contexts. The results from Les Bagnoles demonstrate that oil crops and pulses are underrepresented in dry sites and that they were a significant part of Middle Neolithic agriculture. They also indicate an increase in the representation of einkorn (instead of emmer) during MN2 that is also visible in other open-air sites. The comparison of the archaeobotani-cal results with silo storage capacity values as a proxy for average production capacity per household leads us to propose a possible drop in naked wheat productivity and opens new questions in factors affecting crop choice at the beginning of the 4th millennium cal bc
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