bluuebunny/crossref_metadata_2025 huggingface dataset:
A variational approach for retrieving ice cloud properties from infrared measurements: application in the context of two IIR validation campaigns
Authors: Sourdeval O. , -Labonnote L. C. , Brogniez G. , Jourdan O. , Pelon J. , Garnier A.
Published: August 2013

Abstract. Cirrus are cloud types that are recognized to have a strong impact on the Earth-atmosphere radiation balance. This impact is however still poorly understood, due to the difficulties in describing the large variability of their properties in global climate models. Consequently, numerous airborne and space-borne missions have been dedicated to their study in the last decades. The satellite constellation A-Train has for instance proven to be particularly helpful for the study of cirrus. More particularly, the Infrared Imaging Radiometer (IIR) carried onboard the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite shows a great sensitivity to the radiative and microphysical properties of these clouds. Our study presents a novel methodology that uses the thermal infrared measurements of IIR to retrieve the ice crystal effective size and optical thickness of cirrus. This methodology is based on an optimal estimation scheme, which possesses the advantage of attributing precise uncertainties to the retrieved parameters. Two IIR airborne validation campaigns have been chosen as case studies for illustrating the results of our retrieval method. It is observed that optical thicknesses could be accurately retrieved but that large uncertainties may occur on the effective diameters. Strong agreements have also been found between the products of our method when separately applied to the measurements of IIR and of the airborne radiometer CLIMAT-AV, which consolidates the results of previous validation studies of IIR level-1 measurements. Comparisons with in situ observations and with operational products of IIR are also discussed and appear to be coherent with our results. However, we have found that the quality of our retrievals can be strongly impacted by uncertainties related to the choice of a pristine crystal model and by poor constraints on the properties of possible liquid cloud layers underneath cirrus. Simultaneous retrievals of liquid clouds radiative and microphysical properties and/or the use of different ice crystal models should therefore be considered in order to improve the quality of the results.
Improved satellite retrievals of NO2 and SO2 over the Canadian oil sands and comparisons with surface measurements
Authors: McLinden C. A. , Fioletov V. , Boersma K. F. , Kharol S. K. , Krotkov N. , Lamsal L. , Makar P. A. , Martin R. V. , Veefkind J. P. , Yang K.
Published: August 2013

Abstract. Satellite remote sensing is increasingly being used to monitor air quality over localized sources such as the Canadian oil sands. Following an initial study, significant low biases have been identified in current NO2 and SO2 retrieval products from the Ozone Monitoring instrument (OMI) satellite sensor over this location resulting from a combination of its rapid development and small spatial scale. Air mass factors (AMFs) used to convert line-of-sight "slant" columns to vertical columns were re-calculated for this region based on updated and higher resolution input information including absorber profiles from a regional scale (15 km × 15 km resolution) air quality (AQ) model, higher spatial and temporal resolution surface reflectivity, and an improved treatment of snow. The overall impact of these new Environment Canada (EC) AMFs led to substantial increases in the peak NO2 and SO2 average vertical column density (VCD), occurring over an area of intensive surface mining, by factors of 2 and 1.4, respectively, relative to estimates made with previous AMFs. Comparisons are made with long-term averages of NO2 and SO2 from in-situ surface monitors by using the AQ model to map the OMI VCDs to surface concentrations. This new OMI-EC product is able to capture the spatial distribution of the in-situ instruments (slopes of 0.7 to 1.0; correlation coefficients of 0.9). The concentration absolute values from surface network observations were in reasonable agreement, with OMI-EC NO2 and SO2 biased low by roughly 30%. Several complications were addressed including correction for the interference effect in the surface NO2 instruments and smoothing and clear-sky biases in the OMI measurements. Overall these results highlight the importance of using input information that accounts for the spatial and temporal variability of the location of interest when performing retrievals.
Light scattering at small angles by atmospheric irregular particles: modelling and laboratory measurements
Authors: Lurton T. , Renard J.-B. , Vignelles D. , Jeannot M. , Akiki R. , Mineau J.-L. , Tonnelier T.
Published: August 2013

Abstract. We investigated the behaviour of light scattering by particulates of various sizes (0.1 μm to 100 μm) at a small scattering angle. It was previously shown that for a small angle, the scattered intensities are weakly dependent upon the particulates' nature (Renard et al., 2010). Particles found in the atmosphere exhibit roughness that leads to large discrepancies with the classical Mie solution in terms of scattered intensities in the low angular set-up. This article focuses on building an effective theoretical tool to predict the behaviour of light scattering by real particulates at a small scattering angle. We expose both the classical Mie theory and an adaptation to the case of rough particulates with a fairly simple roughness parametrisation. An experimental device was built, corresponding to the angular set-up of interest (low scattering angle and therefore low angular aperture), and measurements are presented that confirm the theoretical results with a good agreement. It is found that the differences between the classical Mie solution and actual measurements, especially for large particulates, can be attributed to the roughness of particulates. It is also found that, in this low angular set-up, saturation of the scattered intensities occurs for relatively small values of the roughness parameter. This confirms the low variability in the scattered intensities for particulates of different kinds. A direct interest of this study is a broadening of the dynamic range of optical counters: using a small angle of aperture for measurements allows greater dynamics in terms of particle size, and thus enables a single device to observe a broad range of particle sizes whilst utilising the same electronics.
Sediment transport processes across the Tibetan Plateau inferred from robust grain size end-members in lake sediments
Authors: Dietze E. , Maussion F. , Ahlborn M. , Diekmann B. , Hartmann K. , Henkel K. , Kasper T. , Lockot G. , Opitz S. , Haberzettl T.
Published: August 2013

Abstract. Grain size distributions offer powerful proxies of past environmental conditions that are related to sediment sorting processes. However, they are often of multimodal character because sediments can get mixed during deposition. To facilitate the use of grain size as palaeoenvironmental proxy this study aims to distinguish the main detrital processes that contribute to lacustrine sedimentation across the Tibetan Plateau using grain size end-member modelling analysis. Between three and five robust grain size end-member subpopulations were distinguished at different sites from similarly-likely end-member model runs. Their main modes were grouped and linked to sediment transport and depositional processes associated with certain climatic background and catchment configurations. The coarse sands and clays with grain size modes > 250 μm and < 2 μm were probably transported by fluvial processes. Aeolian sands (~ 200 μm) and coarse local dust (~ 60 μm), transported by saltation and in near-surface suspension clouds, are probably related to occasional westerly storms in winter and spring. Coarse regional dust with modes ~ 25 μm may derive from near-by sources that keep in longer-term suspension. The continuous background dust is differentiated into two robust end-members (modes: 5–10 and 2–5 μm) that may represent different sources, wind directions and/or sediment trapping dynamics from long-range, upper-level westerly and episodic northerly wind transport. According to this study grain size end-members of only fluvial origin contribute small amounts to mean Tibetan lake sedimentation (19 ± 5%), whereas local to regional aeolian transport and background dust deposition dominate the clastic sedimentation in Tibetan lakes (contributions: 42 ± 14% and 51 ± 11%). However, fluvial and alluvial reworking of aeolian material from nearby slopes during summer seems to limit end-member interpretation and should be crosschecked with other proxy information. If not considered as a stand-alone proxy, a high transferability to other regions and sediment archives allows helpful reconstructions of past sedimentation history.
Socio-hydrology: conceptualising human-flood interactions
Authors: Di Baldassarre G. , Viglione A. , Carr G. , Kuil L. , Salinas J. L. , Blöschl G.
Published: August 2013

Abstract. Over history, humankind has tended to settle near streams because of the role of rivers as transportation corridors and the fertility of riparian areas. However, human settlements in floodplains have been threatened by the risk of flooding. Possible responses have been to resettle away and/or modify the river system by building flood control structures. This has led to a complex web of interactions and feedback mechanisms between hydrological and social processes in settled floodplains. This paper is an attempt to conceptualise these interplays for hypothetical human-flood systems. We develop a simple, dynamic model to represent the interactions and feedback loops between hydrological and social processes. The model is then used to explore the dynamics of the human-flood system and the effect of changing individual characteristics, including external forcing such as technological development. The results show that the conceptual model is able to reproduce reciprocal effects between floods and people as well as the emergence of typical patterns. For instance, when levees are built or raised to protect floodplain areas, their presence not only reduces the frequency of flooding, but also exacerbates high water levels. Then, because of this exacerbation, higher flood protection levels are required by society. As a result, more and more flooding events are avoided, but rare and catastrophic events take place.
Droughts and floods over the upper catchment of the Blue Nile and their connections to the timing of El Niño and La Niña Events
Authors: Zaroug M. A. H. , Eltahir E. A. B. , Giorgi F.
Published: August 2013

Abstract. The Blue Nile originates from Lake Tana in the Ethiopian Highland and contributes about 67% of the discharge in the main Nile River. Previous studies investigated the relationship of sea surface temperature (SST) in the Pacific Ocean (Nino 3.4 region) to occurrence of floods and droughts in rainfall and river flow over the Nile basin. In this paper we focus on the dependence of occurrence of droughts and floods in the upper catchment of the Blue Nile on the timing of El Niño and La Niña events. Different events start in different times of the year and follow each other exhibiting different patterns and sequences. Here, we study the impact of this timing and temporal patterns on the Nile droughts and floods. We analyze discharge measurements (1965–2012) at the outlet of the upper catchment of the Blue Nile in relation to the El Niño index. When an El Niño event is followed by a La Niña event, there is a 67% chance for occurrence of an extreme flood. The association of start dates of El Niño with occurrence of droughts in the upper catchment of the Blue Nile is evaluated. An El Niño event that starts in (April–June) is associated with a significant drought occurrence in 83% of the cases. We propose that observations as well as global model forecasts of SST during this season could be used in seasonal forecasting of the Blue Nile flow.
The Cretaceous and Cenozoic tectonic evolution of Southeast Asia
Authors: Zahirovic S. , Seton M. , Müller R. D.
Published: August 2013

Abstract. Tectonic reconstructions of Southeast Asia have given rise to numerous controversies which include the accretionary history of Sundaland and the enigmatic tectonic origin of the Proto South China Sea. We assimilate a diversity of geological and geophysical observations into a new regional plate model, coupled to a global model, to address these debates. Our approach takes into account terrane suturing and accretion histories, the location of subducted slabs imaged in mantle tomography in order to constrain the opening and closure history of paleo-ocean basins, as well as plausible absolute and relative plate velocities and tectonic driving mechanisms. We propose a scenario of rifting from northern Gondwana in the Late Jurassic, driven by northward slab pull, to detach East Java, Mangkalihat, southeast Borneo and West Sulawesi blocks that collided with a Tethyan intra-oceanic subduction zone in the mid Cretaceous and subsequently accreted to the Sunda margin (i.e. southwest Borneo core) in the Late Cretaceous. In accounting for the evolution of plate boundaries, we propose that the Philippine Sea Plate originated on the periphery of Tethyan crust forming this northward conveyor. We implement a revised model for the Tethyan intra-oceanic subduction zones to reconcile convergence rates, changes in volcanism and the obduction of ophiolites. In our model the northward margin of Greater India collides with the Kohistan-Ladakh intra-oceanic arc at ∼53 Ma, followed by continent-continent collision closing the Shyok and Indus-Tsangpo suture zones between ∼42 and 34 Ma. We also account for the back-arc opening of the Proto South China Sea from ∼65 Ma, consistent with extension along east Asia and the emplacement of supra-subduction zone ophiolites presently found on the island of Mindoro. The related rifting likely detached the Semitau continental fragment from east China, which accreted to northern Borneo in the mid Eocene, to account for the Sarawak Orogeny. Rifting then re-initiated along southeast China by 37 Ma to open the South China Sea, resulting in the complete consumption of Proto South China Sea by ∼17 Ma when the collision of the Dangerous Grounds and northern Palawan blocks with northern Borneo choked the subduction zone to result in the Sabah Orogeny and the obduction of ophiolites in Palawan and Mindoro. We conclude that the counterclockwise rotation of Borneo was accommodated by oroclinal bending consistent with paleomagnetic constraints, the curved lithospheric lineaments observed in gravity anomalies of the Java Sea and the curvature of the Cretaceous Natuna paleo-subduction zone. We complete our model by constructing a time-dependent network of continuously closing plate boundaries and gridded paleo-ages of oceanic basins, allowing us to test our plate model evolution against seismic tomography. In particular, slabs observed at depths shallower than ∼1000 km beneath northern Borneo and the South China Sea are likely to be remnants of the Proto South China Sea basin.
Cyanobacteria microflora in a limestone spring (Troniny spring, Central Poland)
Authors: Nowicka-Krawczyk Paulina B. , Żelazna-Wieczorek Joanna
Published: August 2013

The paper reports a study of cyanobacterial diversity in a cold-water limestone limnocrene in Central Poland. Samples were collected from 1998 to 2000 and in June 2012. The morphology, population characteristics and species composition of the cyanobacteria assemblages were investigated, and the frequency of taxa was recorded. The large number of taxa identified (30) reflects the microhabitat heterogeneity of this spring. Some species considered epiphytes grew on limestone rocks. The occurrence of the majority of the most frequent taxa was related to the physicochemical characteristics of the spring, but none of them can be considered obligatory crenobionts characteristic of limestone springs. The studied spring is a unique ecosystem with an interesting cyanobacteria microflora whose occurrence is attributable to the spring’s water chemistry, low temperature and variety of microhabitats.
The Preventive Detention of “Dangerous” Sex Offenders in Australia: Perspectives at the Coalface
Authors: Keyzer Patrick , McSherry Bernadette
Published: August 2013

Four Australian states, Queensland, New South Wales, Western Australia and Victoria as well as the Northern Territory have enacted laws that enable the continued detention in prison of “dangerous” sex offenders beyond the completion of their sentence. This has proved to be a popular response from a political and social policy perspective, with the New South Wales government recently extending its scheme to include serious violent offenders. While the Queensland scheme has been upheld by the High Court of Australia as constitutional, preventive detention laws raise human rights issues and problems with implementation. This paper outlines the results of 86 interviews carried out with psychiatrists, psychologists, social workers, former corrective services officials, lawyers and police officers who have firsthand experience with the operation of the Australian schemes. The results indicate that those at the “coalface” in relation to post-sentence preventive detention schemes are critical of a number of matters such as the general reliance on preventive detention rather than rehabilitation, the reliance on and use of risk assessment tools as well as media reporting of sex offenders.
Modelagem de indicadores para avaliar a sustentabilidade da pesca artesanal do entorno da Floresta Nacional do Ibura, nordeste do Brasil
Authors: Silva Carlos Eduardo , Albuquerque Junior Ricardo Luiz Cavalcanti de , Melo Cláudia Moura de , Madi Rubens Riscala
Published: August 2013

O Brasil é detentor da maior biodiversidade do planeta, e não pode se esquivar no tocante ao desenvolvimento de modelos de monitoramento relacionados à conservação da natureza e uso sustentável dos recursos naturais. Neste sentido esta pesquisa teve como objetivo desenvolver um modelo de avaliação de indicadores baseado na metodologia MESMIS (Marco para la Evaluación de Sistemas de Manejo de Recursos Naturales incorporando Indicadores de Sustentabilidade) para sua utilização em nível de comunidades de pescadores ou extrativistas relacionados com Unidades de Conservação (UCs), tomando por base a comunidade de pescadores artesanais existente no entorno da Floresta Nacional do Ibura, Brasil. O MESMIS foi a base metodológica escolhida para desenvolvimento do modelo e avaliação dos indicadores. A estatística descritiva analisou censitariamente (N=100) os parâmetros mínimos (MIN), médios (MED), desejáveis (P75), e máximos (MAX). O modelo resultante é composto por 14 indicadores de sustentabilidade, que atendem os atributos: (a) produtividade; (b) estabilidade, resiliência e confiabilidade; (c) adaptabilidade; (d) equidade; (e) autogestão. É possível concluir que existe viabilidade técnica e matemática para desenvolvimento de modelos de avaliação de sustentabilidade de sistemas baseado em indicadores. Ao serem analisados de forma complexa revelaram que a pesca artesanal desenvolvida no sistema analisado tem um Índice Relativo de Sustentabilidade (IRS) de 26%. Os resultados demonstraram ainda que é possível alcançar um IRS=33% baseando-se na realidade local (P75).
Biocombustíveis no Brasil: mudanças institucionais, competitividade e governança federal
Authors: Sousa Luciano Cunha de , Carvalho Eliezé Bulhões de
Published: August 2013

Este trabalho busca avaliar o setor de biocombustíveis no Brasil sob o ponto de vista das mudanças institucionais ocorridas, seus impactos no modelo de governança e na competitividade sistêmica. Partindo do processo histórico do setor de etanol, foram utilizados os conceitos de competitividade sistêmica, de mudança institucional, equilíbrio pontuado, advocacy coalition framework (ACF) e de governança em rede para a análise do atual arranjo institucional dentro da Administração Pública Federal. A partir de entrevistas com membros do Conselho Interministerial do Açúcar e do Álcool e da Comissão Executiva Interministerial do Biodiesel, que compõem o sistema de governança federal, pode-se observar que, mesmo sendo um importante componente da matriz energética, o setor de biocombustíveis ainda não possui uma estratégia definida de forma ampla, apresentando uma ausência de articulação e fragilidade nos mecanismos de governança no âmbito federal. No setor de etanol principalmente, é constatado que o Conselho Interministerial do Açúcar e do Álcool apresenta dificuldade em estabelecer a estratégia de forma clara e principalmente de comunica-la aos demais integrantes da Administração Pública Federal. As demais bioenergias como o biogás ou a biomassa não são tratadas no âmbito destes órgãos de governança de forma sistêmica e tem ações isoladas sendo executadas de forma desarticulada pelos órgãos da Administração Pública Federal.
Editorial
Authors: Salas Atrain Ricardo
Published: August 2013

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Small-Scale Fishing and Salmon Farming en Aysén. Itinerary of a Critical Investigation into Development in Southern Chile
Authors: Saavedra Gallo Gonzalo
Published: August 2013

This study analyses the economic-cultural responses of twosmall-scale fishing villages of the Aysén coast in the face of the processesof economic development and modernisation currently occurring in theirterritory. The framework in which the problem is defined is the expansionof the caged salmon production industry, and the local promotionof the business mentality by State agencies. In general terms, these twofactors are observed in a process and in a wider spatial context in whichvarious actors coincide. We have called this space the field of development.Although the consequences of the process described —environmentaland territorial, socio-economic, socio-cultural and politico-cultural—may be associated with conventional perspectives, e.g. structural,or reflected in an objectivisation anchored in economic growth indicators,it is also significant to note the subjective aspects implied. We referin particular to the dynamics of practical structuring, which reveal other—unconventional— anthropological dimensions to the process. Underthis consideration we propose a horizontal hypothetical framework, inwhich we maintain that the decisive factors for economic developmentdo not emanate solely from public policy and/or the structuring and/ordestructuring forces of the market, since these capitalist modernisationprocesses are conditioned by dynamics of social and cultural structuringexpressed in the coastal-local development space.
Participation of Small-Scale Fishermen in the Design of a Project for Creating Artificial Reefs in the South of Brazil
Authors: Andriguetto-Filho José Milton , Pierri Naina
Published: August 2013

Since 2004, a project has been in progress off the coast of ParanáState (Brazil) to set up artificial reefs and anti-trawling units on the shallowcontinental shelf. The object is to restrict large-scale bottom trawling inorder to protect and recover marine biodiversity and fish stocks, thus favouringthe sustainability of small-scale fishing. In 2005, the authors wereinvited to carry out a public participation process for the fishermen directlyaffected. The method consisted in organising four municipal discussion forums,plus a final joint meeting. Each event was preceded by intense publicity,and various communication and information techniques were used.Starting from an initial proposal for the location of the structures, and a presentationon the advantages and disadvantages of intervention, the first objectivewas to allow the fishermen to accept or reject the proposal. If it wasaccepted, the next decision was to fix the details of the spatial distributionof the structures. Acceptance was widespread, except in one district whereindustrial-scale trawling is practiced. The process revealed internal conflictsin the fishermen’s society, as well as gaps in the researchers’ knowledge offisheries and the local ecology, and the possible impacts of the project, leadingto redesign. This consultation constituted an unprecedented democratic,participative process in the history of fishery management in Paraná,which has become a regional and national reference.
Environmental history of the Trapananda Archipelagos (Northern Patagonia, Chile): challenges for the conservation of the blue whale
Authors: Solari María Eugenia , Skewes Juan Carlos , Navarro Magdalena , Paillacheo Fabian
Published: August 2013

The reappearance of the blue whale in southern Chile in 2003has meant a number challenges for national conservation policies. It is alsocreated an opportunity to re-think the history of the southern seas and thatof the Aysen coastline in particular. The social landscape of this coastlineis characterized by poverty and passage between two well known regionChiloe and Austral Patagonia. This is an extreme environment in whichinhabitants have developed a number of adaptive strategies linked to forestand marine systems. These strategies are well documented in the historical,archaeological and ethnographic records which we will gather in order toreconstruct the environmental history of the region. Archaeo-historical recordsevidenced canoes were vital for the first inhabitants of this area. Theirrelationship with nature was based on the extensive used of resources whichin turn facilitated their integration to the local landscape characterized bythe abundance of archipelagos. This relationship was modified after a numberof historical processes unchained after the inclusion of this area to thenational economy plans. These processes promoted continuous waves ofsettlement into the region, mainly to the coastline of Aysen, modifying thetraditional adaptive strategies and promoting an intensive and abusive usedof this intrinsically labile and non-renewable landscape. The opportunity tocompile the environmental history of this area and contribute to its protectionalong with the blue whale is the challenge we present here.
Reseña Pescadores en América Latina y el Caribe. Espacio, Población, Producción y Política
Authors: Álvarez Burgos Catalina
Published: August 2013

Pescadores en América Latina y el Caribe. Espacio, Población, Producción y Política
Graciela Alcalá Moya, Editora, Alejandro Camargo, Asistente de edición. – México : Facultad de Ciencias, Unidad Multidisciplinaria de Docencia e Investigación, SISAL, Universidad Nacional Autónoma de México, Primera Edición, 2011 (Vol. I, 380 p.; Vol. II, 420 p.)
Pandilla 18 y Mara Salvatrucha 13: violencia y desciudadanización
Authors: Moreno Hernández Hugo , Sánchez González Mónica
Published: August 2013

El presente trabajo es parte de una investigación sobre formasde reestratificación desde la sociedad civil. Aquí se observan las estrategiasinstitucionales para el tratamiento del fenómeno de las pandillas transnacionalesllevadas a cabo en El Salvador. Se observa cómo estas estrategiasproducen mayor violencia, sin presentar opciones organizativas orientadasa mejorar la vida de los jóvenes pandilleros, sin buscar crear formas socialesproductivas en el sentido de asegurar a los jóvenes marginales instanciasde resistencia a los influjos del sistema capitalista que los excluye. En estostérminos, se propone observar las estrategias gubernamentales y sus efectosen la transformación de las pandillas hacia formas más violentas y jerarquizadas,debido a la acción criminalizante de las instituciones del gobierno.Así pues, se propone la observación de la reestratificación institucional delas pandillas, mediante la criminalización y su asimilación al crimen organizado,como elemento que ha producido una tendencia a la jerarquización,la clandestinidad y el aumento de la violencia
Pueblos indígenas y Extranjeros en la Monarquía Hispánica: La imagen del otro en tiempos de guerra (Siglos XVI-XIX)
Authors: Salgado Ismodes Italo
Published: August 2013

Pueblos indígenas y Extranjeros en la Monarquía Hispánica: La imagen del otro en tiempos de guerra (Siglos XVI-XIX)
David González Cruz (Editor)
Sílex Ediciones, Madrid, 2011.
Heterogeneity and Tension Between Different Ways of Understanding Development. An Anthropological Study of Coexistence Between Forestry Companies and Mapuche Communities in the Araucanía Region of Chile
Authors: Carrasco Henríquez Noelia
Published: August 2013

This paper presents key research findings about the relationshipbetween forestry companies and Mapuche communities in Chile, from theperspective of anthropological studies of development, adressed during theFondecyt proyect 11080196. Methodologically, the research is the result ofintensive and extensive ethnographic approach on the dynamics and relationalprocesses between the actors, during the 2008-2011 period. Interviews,participant observation and document analysis were the main strategiesused. The main results higlight that both sector —forestry companies andthe Mapuche communities— has its own internal diversity, trends and tensions,that impact the overall social relations quality in the territory of LaAraucania, which is historically and socially marked by cultural and economicgaps. The research allowed to see that in this context, the relationshipbetween forestry companies and the Mapuche community reflects contactsbetween different logics —ie. modes, styles, value systems, practices andperformed knowledges, relating to the environment, development and theeconomy. These contacts —sociologically understood as social relations—are flexible, but always within a range of inequalities that undermine communities
Las Ciencias Sociales “desde” el Sur “para el Mundo”. Discurso de Instalación de Decano de la Facultad de Ciencias Sociales de la Universidad Católica de Temuco. Lunes 2 de abril 2012.
Authors: Zavala Cepeda José Manuel
Published: August 2013

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Editorial
Authors: Paillavil Samuel , Zavala Cepeda José Manuel
Published: August 2013

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Excellent Field‐Emission Performances of Neodymium Hexaboride (NdB6) Nanoneedles with Ultra‐Low Work Functions
Authors: Xu Junqi , Hou Guanghua , Mori Takao , Li Huiqiao , Wang Yanrui , Chang Yangyang , Luo Yongsong , Yu Benhai , Ma Ying , Zhai Tianyou
Published: August 2013

High‐quality NdB6 nanostructures with a low work function are successfully synthesized via an one‐step catalyst‐free chemical vapor deposition process. Field emission properties of these nanostructures (curve nanowires, short‐straight nanorods, long‐straight nanowires, and nanoneedles) are systematically investigated and found to be strongly affected by the tip morphologies and temperatures. The nanoneedles with sharp tips demonstrate the lowest turn‐on (2.71 V/μm) and threshold (3.60 V/μm) electric fields, as well as a high current density (5.37 mA/cm2) at a field of 4.32 V/μm in comparision with other nanostructures. Furthermore, with an increase in temperature from room temperature to 623 K, the turn‐on field of the nanoneedles decreases from 2.71 to 1.76 V/μm, and the threshold field decreases from 3.60 to 2.57 V/μm. Such excellent performances make NdB6 nanomaterials promising candidates for application in flat panel displays and nanoelectronics building blocks.
Molecular and thermodynamic basis for EGCG‐Keratin interaction‐part II: Experimental investigation
Authors: Zhao Yanyan , Chen Longjian , Han Lujia , Marzinek Jan K. , Mantalaris Athanasios , Pistikopoulos Efstratios N. , Marzinek Jan K. , Lian Guoping , Bond Peter J. , Noro Massimo G.
Published: August 2013

In Part I, we reported all‐atom, fully solvated molecular dynamics (MD) simulations of epigallocatechin‐3‐gallate (EGCG) binding to keratin. Herein, we report the second part of experimental investigation on EGCG binding to keratin using ultrafiltration and isothermal titration calorimetry (ITC). The thermodynamic equilibrium of EGCG binding to keratin has been quantitatively determined using ultrafiltration and high‐performance liquid chromatography−UV/vis. The relationship confirms multilayer binding of EGCG to keratin which was observed in MD simulations. By combining the ultrafiltration and ITC data, the thermodynamic parameters of EGCG binding to keratin have been quantified. The obtained free energy of the first layer binding (ΔG = −6.37 kcal mol−1) is shown in excellent agreement with that obtained from computer simulations (ΔG = −6.20 kcal mol−1) presented in Part I. © 2013 American Institute of Chemical Engineers AIChE J, 59: 4824–4827, 2013
Preparation, characterization, and performance evaluation of coated PES polymer materials fabricated via dry/wet phase inversion technique
Authors: Kim KeeHong , Hyung ChanHeui , Ingole Pravin G. , Kim JongHak , Lee HyungKeun
Published: August 2013

Sulfur dioxide (SO2) is the major air pollutant which is emitted from the power plant. In this study, hollow fiber membrane (HFM) separation process is applied for the improvement of SO2 removal efficiency in the post‐combustion gas. HFM was produced by dry/wet phase inversion method and then coated with Polydimethylsiloxane (PDMS). The membrane morphology and characterization were examined with help of scanning electron microscope (SEM), energy dispersion of X‐ray spectroscopy (EDX), Fourier transform infrared (FT‐IR) and atomic force microscopy (AFM). Polyethersulfone (PES) hollow fiber membranes were tested for the SO2/N2 binary mixed gas separation. Single gas permeance of SO2, N2, and binary mixture gas (200 ppm of SO2) separation experiment was initiated to observe membrane behavior according to temperature and pressure difference and retentate flow rate. As a result, permeance of SO2 was 24.9–47.4 GPU and selectivity of SO2/N2 was 1.6–4.2. From the mixture gas separation experiment, SO2 removal efficiency increased according to stage cut and operating pressure. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39711.
Lignin‐xylaric acid‐polyurethane‐based polymer network systems: Preparation and characterization
Authors: Pohjanlehto Helinä , Setälä Harri M. , Kiely Donald E. , McDonald Armando G.
Published: August 2013

Polyurethanes (PU) were synthesized from lignin by first preparing a prepolymer from esterified sugar‐based trihydroxyl compound xylaric acid and a 20 mol % excess of methylene diphenyl diisocyanate. The prepolymer was crosslinked with 5, 10, and 15 wt % of an industrial soda lignin, and polyethylene glycol was used to bring soft segments into the material structure. The total amount of bio‐based starting materials was as high as 35%. Evidence for the reaction between the prepolymer and lignin was observed using Fourier transform infrared spectroscopic analysis and 13C nuclear magnetic resonance spectroscopy. The thermal properties of the materials were investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The mechanical and viscoelastic properties of the materials were determined by dynamic mechanical analysis (DMA). The glass transition temperatures (Tg) obtained from DSC and DMA showed a trend of increasing Tg with the increasing amount of lignin. A similar trend was observed with TGA for the increasing thermal stability up to 550oC with the increasing amount of lignin. The lignin‐polyurethanes obtained were stiff materials showing high Young's modulus values. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39714.
Transport of nitric oxide by perfluorocarbon emulsion
Authors: Ortiz Daniel , Cabrales Pedro , Briceño Juan C.
Published: August 2013

Perfluorocarbon (PFC) emulsions can transport and release various gases based on concentration gradients. The objective of this study was to determine the possibility of carrying and delivering exogenous nitric oxide (NO) into the circulation by simply loading PFC emulsion with NO prior infusion. PFC was equilibrated with room air (PFC) or 300 ppm NO (PFC‐NO) at atmospheric pressure. Isotonic saline solution was used as a volume control (Saline). PFC and PFC‐NO were infused at a dose of 3.5 mL/kg in the hamster window chamber model. Blood chemistry, and systemic and microvascular hemodynamic response were measured. Infusion of PFC preloaded with NO reduced blood pressure, induced microvascular vasodilation and increased capillary perfusion; although these changes lasted less than 30 min post infusion. On the other hand, infusion of PFC (without NO) produced vasoconstriction; however, the vasoconstriction was followed by vasodilatation at 30 min post infusion. Plasma nitrite and nitrate increased 15 min after infusion of NO preloaded PFC compared with PFC, 60 min after infusion nitrite and nitrate were not different, and 90 min after infusion plasma S‐nitrosothiols increased in both groups. Infusion of NO preloaded PFC resulted in acute vascular relaxation, where as infusion of PFC (without NO) produced vasoconstriction, potentially due to NO sequestration by the PFC micelles. The late effects of PFC infusion are due to NO redistribution and plasma S‐nitrosothiols. Gas solubility in PFC can provide a tool to modulate plasma vasoactive NO forms availability and improve microcirculatory function and promote increased blood flow. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29:1565–1572, 2013
Posterior tibiotalar ligament: An anatomic study correlated with MRI
Authors: Won Hyung‐Jin , Won Hyung‐Sun , Oh Chang‐Seok , Han Seung‐Ho , Chung In‐Hyuk , Suh Jin‐Suck , Lee Woo‐Chun
Published: August 2013

This study was performed to clarify the morphologic characteristics of two layers of the posterior tibiotalar ligament (PTT) and two bands of the deep PTT (dPTT), and to correlate the dissection findings with MR images. Sixty‐four ankles from 42 cadavers were examined. The origin and insertion sites of the superficial PTT (sPTT) and the two bands of the dPTT were identified, and their length, width, and thickness were measured. MRI was performed on four ankles before serial sectioning or dissection. The serial sections were taken at a thickness of 2 mm. The sPTT was observed in 50 out of 60 dissected specimens (83.3%), taken from 64 ankles of 42 cadavers. The dPTT was observed in all specimens. The sPTT, superficial band of the dPTT (sdPTT), and deep band of the dPTT (ddPTT) arose from the inferior surface of the medial malleolus. The sPTT attached to the posterior process of the talus, and the sdPTT and ddPTT attached to the depression below the articular facet for the medial malleolus. The sPTT and two bands of the dPTT could be distinguished on coronal MR images, where the sPTT appeared as a thin string superficial to the two bands of the dPTT, which were separated as two thick, low‐density strings. In the coronal plane of frozen sections, the outermost sPTT appeared as a thin, white bundle attached to the sdPTT. The PTT is composed of superficial and deep layers, and the dPTT is composed of superficial and deep bands. Clin. Anat. 27:798–803, 2014. © 2013 Wiley Periodicals, Inc.
Theoretical and Experimental Analysis of the Reaction Mechanism of MrTPS2, a Triquinane‐Forming Sesquiterpene Synthase from Chamomile
Authors: Hong Young J. , Irmisch Sandra , Wang Selina C. , Garms Stefan , Gershenzon Jonathan , Zu Liansuo , Köllner Tobias G. , Tantillo Dean J.
Published: August 2013

Terpene synthases, as key enzymes of terpene biosynthesis, have garnered the attention of chemists and biologists for many years. Their carbocationic reaction mechanisms are responsible for the huge variety of terpene structures in nature. These mechanisms are amenable to study by using classical biochemical approaches as well as computational analysis, and in this study we combine quantum‐chemical calculations and deuterium‐labeling experiments to elucidate the reaction mechanism of a triquinane forming sesquiterpene synthase from chamomile. Our results suggest that the reaction from farnesyl diphosphate to triquinanes proceeds through caryophyllyl and presilphiperfolanyl cations and involves the protonation of a stable (−)‐(E)‐β‐caryophyllene intermediate. A tyrosine residue was identified that appears to be involved in the proton‐transfer process.
Functionalized Organotin‐Chalcogenide Complexes That Exhibit Defect Heterocubane Scaffolds: Formation, Synthesis, and Characterization
Authors: Eußner Jens P. , Barth Beatrix E. K. , Leusmann Eliza , You Zhiliang , Rinn Niklas , Dehnen Stefanie
Published: August 2013

The synthesis of new functionalized organotin‐chalcogenide complexes was achieved by systematic optimization of the reaction conditions. The structures of compounds [(R1, 2Sn)3S4Cl] (1, 2), [((R2Sn)2SnS4)2(μ‐S)2] (3), [(R1, 2Sn)3Se4][SnCl3] (4, 5), and [Li(thf)n][(R3Sn)(HR3Sn)2Se4Cl] (6), in which R1=CMe2CH2C(O)Me, R2=CMe2CH2C(NNH2)Me, and R3=CH2CH2COO, are based on defect heterocubane scaffolds, as shown by X‐ray diffraction, 119Sn NMR spectroscopy, and ESI mass spectrometry analyses. Compounds 4, 5, and 6 constitute the first examples of defect heterocubane‐type metal‐chalcogenide complexes that are comprised of selenide ligands. Comprehensive DFT calculations prompted us to search for the formal intermediates [(R1SnCl2)2(μ‐S)] (7) and [(R1SnCl)2(μ‐S)2] (8), which were isolated and helped to understand the stepwise formation of compounds 1–6.
Allenylidene Complexes Based on Pentacenequinone
Authors: Strinitz Frank , Waterloo Andreas , Tucher Johannes , Hübner Eike , Tykwinski Rik R. , Burzlaff Nicolai
Published: August 2013

Stable ruthenium–allenylidene complexes based on pentacenequinone have been synthesized. The complexes show an electronic absorption in the NIR region that arises from forbidden MLCT transitions, as explained by DFT calculations. The crystal structure reveals promising features for the formation of metal‐influenced organic FETs.
Synthesis and Crystal Structures of [(iPr3P)2Cu(μ‐ESiMe3)(InMe3)] (E = S, Se): Lewis Acid–Base Adducts with Chalcogen Atoms in Planar Coordination
Authors: Biedermann Ralf , Kluge Oliver , Fuhrmann Daniel , Krautscheid Harald
Published: August 2013

The structures of [(iPr3P)2Cu(μ‐SSiMe3)(InMe3)] and [(iPr3P)2Cu(μ‐SeSiMe3)(InMe3)] were determined by single‐crystal X‐ray diffraction. Both complexes are Lewis acid–base adducts of the InMe3 acceptor and the chalcogen donor atom linking a Me3Si group and a (iPr3P)2Cu moiety. They are very unstable under atmospheric conditions and decompose at ambient temperatures. Results of DFT calculations for these complexes and the related hypothetical [(Me3P)2Cu(μ‐SSiMe3)(InMe3)] compound show that the unusual planar coordination of the chalcogen atoms is due to steric crowding.
Ionic‐Liquid‐Assisted Synthesis of Self‐Assembled TiO2‐B Nanosheets under Microwave Irradiation and Their Enhanced Lithium Storage Properties
Authors: Chen Chaoji , Hu Xianluo , Hu Pei , Qiao Yun , Qie Long , Huang Yunhui
Published: August 2013

Self‐assembled TiO2‐B nanosheets have been successfully synthesized by a rapid, one‐pot, ionic‐liquid‐assisted solvothermal route under microwave irritation. By adjusting the reaction temperature, reaction time, and reactant concentration, the morphology and phase of the as‐formed TiO2‐B nanostructures can be tailored. The unique role of the ionic liquid in the formation of self‐assembled TiO2 nanosheets has been investigated in detail, and a plausible growth mechanism has been proposed. Owing to the synergetic superiority of hierarchical porosity, a fast pseudocapacitive reaction, and large surface area, the electrode prepared from the self‐assembled porous TiO2‐B nanostructures exhibits high reversible capacity, excellent cyclability, and superior rate capability. The synthetic procedure is simple, efficient, and scalable for mass production. Therefore the as‐formed self‐assembled TiO2‐B nanosheets may offer great potential for next‐generation rechargeable batteries with high‐power densities, and are flexible building blocks for advanced functional devices.
Evaluating the sorption of organophosphate esters to different sourced humic acids and its effects on the toxicity to Daphnia magna
Authors: Pang Long , Liu Jingfu , Yin Yongguang , Shen Mohai
Published: August 2013

Because of large usage as flame retardants and additives, organophosphate esters (OPEs) are widely detected in the environment and regarded as emerging contaminants. However, the sorption of OPEs to organic matter and its effects have scarcely been studied. In the present study, the sorption of 9 commonly used OPEs to 4 representative humic acids—Elliott Soil humic acid, Suwannee River humic acid, Aldrich humic acid, and Acros humic acid—in the range of 0 mg/L to 50 mg/L dissolved organic carbon (DOC), was evaluated with negligible-depletion solid-phase microextraction and verified by its impacts on the toxicity to the aquatic invertebrate Daphnia magna. Whereas OPEs with a high octanol/water partition coefficient (log KOW = 4.51 − 6.64) were associated with humic acids mainly by hydrophobic interaction with DOC partition coefficient (KDOC) in the range of 102.22 to 105.31, the sorption of low-KOW OPEs (log KOW = −0.65 to 2.59) to humic acids was not hydrophobic interaction–dominant, with KDOC in the range of 103.47 to 104.29. These results were corroborated by the effects of humic acids on the acute toxicity of 3 high-KOW OPEs to D. magna. The sorption of OPEs to Suwannee River humic acid was weak and had negligible effects on the toxicity of high-KOW OPEs; the presence of terrestrial Acros humic acid (50 mg/L DOC), however, significantly decreased the toxicity by 53% to 60%. The results indicated that the strong sorption between high-KOW OPEs and terrestrial humic acid might affect their transportation and bioavailability. Environ Toxicol Chem 2013;32:2755–2761. © 2013 SETAC
Photosynthetic and cellular toxicity of cadmium in Chlorella vulgaris
Authors: Ou-Yang Hui-Ling , Kong Xiang-Zhen , Lavoie Michel , He Wei , Qin Ning , He Qi-Shuang , Yang Bin , Wang Rong , Xu Fu-Liu
Published: August 2013

The toxic effects of cadmium (Cd) on the green alga Chlorella vulgaris were investigated by following the response to Cd of various toxicity endpoints (cell growth, cell size, photochemical efficiency of PSII in the light or ΦPSII , maximal photochemical efficiency or Fv/Fm, chlorophyll a fluorescence, esterase activity, and cell viability). These toxicity endpoints were studied in laboratory batch cultures of C. vulgaris over a long-term 96-h exposure to different Cd concentrations using flow cytometry and pulse amplitude modulated fluorometry. The sequence of sensitivity of these toxicity endpoints was: cell yield >> ΦPSII ≈ esterase activity > Fv/Fm > chlorophyll a fluorescence ≈ cell viability. It is shown that cell apoptosis or cell death only accounted for a minor part of the reduction in cell yield even at very high algistatic free Cd2+ concentrations, and other mechanisms such as blocked cell divisions are major contributors to cell yield inhibition. Furthermore, cadmium may affect both the electron donors and acceptors of the electron transport chain at high free Cd2+ concentration. Finally, the resistance of cells to cell death was size-dependent; medium-sized cells had the highest toxicity threshold. The present study brings new insights into the toxicity mechanisms of Cd in C. vulgaris and provides a detailed comparison of the sensitivity of various Cd toxicity endpoints. Environ Toxicol Chem 2013;32:2762–2770. © 2013 SETAC