bluuebunny/crossref_metadata_2025 huggingface dataset:
Saltwater intrusion into tidal freshwater marshes alters the biogeochemical processing of organic carbon
Authors: Neubauer S. C. , Franklin R. B. , Berrier D. J.
Published: December 2013

Abstract. Environmental perturbations in wetlands affect the integrated plant-microbial-soil system, causing biogeochemical responses that can manifest at local to global scales. The objective of this study was to determine how saltwater intrusion affects carbon mineralization and greenhouse gas production in coastal wetlands. Working with tidal freshwater marsh soils that had experienced ~ 3.5 yr of in situ saltwater additions, we quantified changes in soil properties, measured extracellular enzyme activity associated with organic matter breakdown, and determined potential rates of anaerobic carbon dioxide (CO2) and methane (CH4) production. Soils from the field plots treated with brackish water had lower carbon content and higher C : N ratios than soils from freshwater plots, indicating that saltwater intrusion reduced carbon availability and increased organic matter recalcitrance. This was reflected in reduced activities of enzymes associated with the hydrolysis of cellulose and the oxidation of lignin, leading to reduced rates of soil CO2 and CH4 production. The effects of long-term saltwater additions contrasted with the effects of short-term exposure to brackish water during three-day laboratory incubations, which increased rates of CO2 production but lowered rates of CH4 production. Collectively, our data suggest that the long-term effect of saltwater intrusion on soil CO2 production is indirect, mediated through the effects of elevated salinity on the quantity and quality of autochthonous organic matter inputs to the soil. In contrast, salinity, organic matter content, and enzyme activities directly influence CH4 production. Our analyses demonstrate that saltwater intrusion into tidal freshwater marshes affects the entire process of carbon mineralization, from the availability of organic carbon through its terminal metabolism to CO2 and/or CH4, and illustrate that long-term shifts in biogeochemical functioning are not necessarily consistent with short-term disturbance-type responses.
Controls on the magnitude-frequency scaling of an inventory of secular landslides
Authors: Hurst M. D. , Ellis M. A. , Royse K. R. , Lee K. A. , Freeborough K.
Published: December 2013

Abstract. Linking landslide size and frequency is important at both human and geological timescales for quantifying both landslide hazards and the effectiveness of landslides in the removal of sediment from evolving landscapes. The statistical behaviour of the magnitude-frequency of landslide inventories is usually compiled following a particular triggering event such as an earthquake or storm, and their statistical behaviour is often characterised by a power-law relationship with a small landslide rollover. The occurrence of landslides is expected to be influenced by the material properties of rock and/or regolith in which failure occurs. Here we explore the statistical behaviour and the controls of a secular landslide inventory (SLI) (i.e. events occurring over an indefinite geological time period) consisting of mapped landslide deposits and their underlying lithology (bedrock or superficial) across the United Kingdom. The magnitude-frequency distribution of this secular inventory exhibits an inflected power-law relationship, well approximated by either an inverse gamma or double Pareto model. The scaling exponent for the power-law scaling of medium to large landslides is α = −1.71 ± 0.02. The small-event rollover occurs at a significantly higher magnitude (1.0–7.0 × 10−3 km2) than observed in single-event landslide records (~ 4 × 10−3 km2). We interpret this as evidence of landscape annealing, from which we infer that the SLI underestimates the frequency of small landslides. This is supported by a subset of data where a complete landslide inventory was recently mapped. Large landslides also appear to be under-represented relative to model predictions. There are several possible reasons for this, including an incomplete data set, an incomplete landscape (i.e. relatively steep slopes are under-represented), and/or temporal transience in landslide activity during emergence from the last glacial maximum toward a generally more stable late-Holocene state. The proposed process of landscape annealing and the possibility of a transient hillslope response have the consequence that it is not possible to use the statistical properties of the current SLI database to rigorously constrain probabilities of future landslides in the UK.
Climate and topographic controls on pasture production in a semiarid Mediterranean watershed with scattered tree cover
Authors: Lozano-Parra J. , Maneta M. P. , Schnabel S.
Published: December 2013

Abstract. Natural grasses in semiarid rangelands constitute an effective protection against soil erosion and degradation, are a source of natural food for livestock and play a critical role in the hydrologic cycle by contributing to the uptake and transpiration of water. However, natural pastures are threatened by land abandonment and the consequent encroachment of shrubs and trees as well as by changing climatic conditions. In spite of their ecological and economic importance, the spatio-temporal variations of pasture production at the decadal to century scales over whole watersheds are poorly known. We used a physics-based, spatially-distributed ecohydrologic model applied to a 99.5 ha semiarid watershed in western Spain to investigate the sensitivity of pasture production to climate variability. The ecohydrologic model was run using a 300 yr long synthetic daily climate dataset generated using a stochastic weather generator. The data set reproduced the range of climatic variations observed under current climate. Results indicated that variation of pasture production largely depended on factors that also determined the availability of soil moisture such as the temporal distribution of precipitation, topography, and tree canopy cover. The latter is negatively related with production, reflecting the importance of rainfall and light interception, as well as water consumption by trees. Valley bottoms and flat areas in the lower parts of the catchment are characterized by higher pasture production. A quantitative assessment of the quality of the simulations showed that ecohydrologic models are a valuable tool to investigate long term (century scale) water and energy fluxes, as well as vegetation dynamics, in semiarid rangelands.
Challenges in conditioning a stochastic geological model of a heterogeneous glacial aquifer to a comprehensive soft dataset
Authors: Koch J. , He X. , Jensen K. H. , Refsgaard J. C.
Published: December 2013

Abstract. In traditional hydrogeological investigations, one geological model is often used based on subjective interpretations and sparse data availability. This deterministic approach usually does not account for any uncertainties. Stochastic simulation methods address this problem and can capture the geological structure uncertainty. In this study the geostatistical software TProGS is utilized to simulate an ensemble of realizations for a binary (sand/clay) hydrofacies model in the Norsminde catchment, Denmark. TProGS can incorporate soft data, which represent the associated level of uncertainty. High density (20 m × 20 m × 2 m) airborne geophysical data (SkyTEM) and categorized borehole data are utilized to define the model of spatial variability and for soft conditioning the TProGS simulations. The category probabilities for the SkyTEM dataset are derived from a histogram probability matching method, where resistivity is paired with the corresponding lithology from the categorized borehole data. A novelty of this study is the incorporation of two distinct datasources into the stochastic modeling process that represents two extremes of the conditioning density spectrum; sparse borehole data and abundant SkyTEM data. The high density of spatially correlated SkyTEM data lead to very deterministic simulation results. This is caused by overconditioning and addressed by a work around utilizing a resampling (thinning) of the dataset. In the case of abundant conditioning data it is shown that TProGS is capable of reproducing non-stationary trends. The stochastic realizations are validated by five performance criteria: (1) sand proportion, (2) mean length, (3) geobody connectivity, (4) facies probability distribution and (5) facies probability – resistivity bias. As conclusion, a stochastically generated set of realizations soft conditioned to 200 m moving sampling of geophysical data performs most satisfying when balancing the five performance criteria and can be used in subsequent hydrogeological flow modeling to address the predictive uncertainty originated from the geological structure uncertainty.
Vector model of the timing diagram of automatic machine
Authors: Jomartov A.
Published: December 2013

Abstract. In this paper a vector model of timing diagram of automatic machine is developed, which allows us to solve a variety dynamic tasks by changing the parameters of timing diagram of its mechanisms. The connection between the parameters of the timing diagram of automatic machine and equations of motion mechanisms through functions of position and transfer functions of mechanisms is established. The vector model of timing diagram can be used to optimize the timing diagrams of looms and polygraphic machines.
Seasonal changes in the soil hydrological and erosive response depending on aspect, vegetation type and soil water repellency in different Mediterranean microenvironments
Authors: Gabarrón-Galeote M. A. , Martínez-Murillo J. F. , Quesada M. A. , Ruiz-Sinoga J. D.
Published: December 2013

Abstract. Mediterranean areas are characterized by a strong spatial variability that makes the soil hydrological response highly complex. Moreover, Mediterranean climate has marked seasons that provoke dramatic changes on soil properties determining the runoff rates, such as soil water content or soil water repellency (SWR). Thus, soil hydrological and erosive response in Mediterranean areas can be highly time- as well as space-dependant. This study shows SWR, aspect and vegetation as factors of the soil hydrological and erosive response. Erosion plots were set up in the north- and the south-facing hillslope and rainfall, runoff, sediments and SWR were monitored. Soil water repellency showed a seasonal behaviour and it was presented in three out of four microenvironments after the summer, disappearing in the wet season. In general, runoff rate was higher in shrubs patches (0.47 ± 0.67 mm) than in inter-shrub soils (1.54 ± 2.14 mm), but it changed seasonally in different ways, depending on the aspect considered, decreasing in the north-facing hillslope and increasing in the south-facing one. The main factor determining the hydrological and erosive response was the rainfall intensity, regardless of the rainfall depth of the event. This response was modulated mainly by SWR in the north-facing hillslope and the vegetation pattern in the south-facing one.
Mass change of Arctic ice caps and glaciers: implications of regionalizing elevation changes
Authors: Nilsson J. , Sandberg Sørensen L. , Barletta V. R. , Forsberg R.
Published: December 2013

Abstract. Recent studies have determined mass changes of Arctic ice caps and glaciers from satellite altimetry. Determining regional mass balance of ice caps and glaciers using this technique is inherently difficult due to their size and geometry. Furthermore these studies have mostly relied on one method or the same types of methods to determine the regional mass balance, by extrapolating elevation changes using their relation to elevation. This makes the estimation of mass balance heavily dependent on the method used to regionalize the elevation changes. Left without consideration large discrepancies can arise in the mass change estimates and the interpretation of them. In this study we use Ice, Cloud, and land Elevation Satellite (ICESat) derived elevation changes from 2003–2009 and determine the impact of different regionalizing schemes on the mass change estimates of the Arctic ice caps and glaciers. Four different methods, based on interpolation and extrapolation of the elevation changes were used to quantify this effect on the regional mass changes. Secondly, a statistical criteria was developed to determine the optimum method for each region in order to derive robust mass changes and reduce the need of external validation data. In this study we found that the range or spread of the estimated mass changes, for the different regions, was highly correlated to the inter-annual variability of the elevation changes, driven by the different climatic conditions of the regions. Regions affected by a maritime climate show a large range in estimated values, on average 1.5–2 times larger than the predicted errors. For regions in a continental regime the opposite was observed, and the range of the values lies well inside the error estimates. We also found that the extrapolation methods tend on average to produce more negative values than the interpolation methods and that our four methods do not fully reproduce the original histogram. Instead, they produce more negative distributions than the original which may indicate that previous and these current estimates using ICESat observations might be overestimate by as much as 4–19%, depending on region. This should therefore be taken into account when deriving regional mass balance from satellite altimetry in regions which show high inter-annual variability of elevation changes. In these regions several different independent methods should be used to capture the elevation change pattern and then analyzed to determine the most suitable method. For regions in a continental climate regime, and with low variability of elevation changes, a single method may be sufficient to capture the regional elevation change pattern and hence mass balance.
Review Essay: Daniel Morgan, Late Godard and the Possibilities of Cinema
Authors: Ryder Andrew
Published: December 2013

A review of Daniel Morgan, Late Godard and the Possibilities of Cinema (Berkeley, CA: University of California Press, 2013).
Claude Romano au carrefour de la phénoménologie française
Authors: Canullo Carla
Published: December 2013

Au carrefour de la phénoménologie française contemporaine   Depuis la fin des années ’90, la réflexion sur l’événement a permis de compter Claude Romano parmi les protagonistes de la phénoménologie française contemporaine. Sa proposition phénoménologique s’est ensuite nouée (grâce à l’endurante lecture des romans de Faulkner) à l’inouï débordement de l’événement de la vie que le récit est censé redonner, pour ainsi dire, "en elle-même" et à l’abri de toute sorte de réduction. L’enjeu de ces pages – consacrées à l’ouvrage de Claude Romano paru en 2010, Au cœur de la raison, la phénoménologie – sera la même répétition de la phénoménologie que Romano nous a livrée dans cet ouvrage. En effet, notre avis est que Romano, en 2010, a pratiqué une Wiederholung de la phénoménologie et qu’il l’a fait situant celle-ci au centre d’un carrefour où confluent les questions historiques (Husserl, Heidegger), les libres variations de la phénoménologie en France (Sartre, Merleau-Ponty, Levinas), la philosophie analytique. Or par cette répétition il s’est installé au carrefour de la phénoménologie française contemporaine, et cela pour deux raisons : premièrement, parce qu’il a donné une contribution décisive à l’alternative "réduction vs intentionnalité" qui ne cesse de représenter l’alternative de la réception française de la phénoménologie. Deuxièmement, parce que par sa répétition il a ouvert aussi un chemin nouveau et original qui maintenant demande à être phénoménologiquement questionné.
Notes pour une phénoménologie de la naissance: En dialogue avec Claude Romano
Authors: Tarditi Claudio
Published: December 2013

Cet article cherche à discuter certaines implications de la phénoménologie événémentiale de Romano afin d'en mésurer la fécondité pour la question - largement négligée par notre tradition philosophique - de la naissance. A travers la critique de la notion de "conscience interne du temps" proposée par Husserl dans les Leçons de 1905 et les Manuscrits de Bernau de 1918-19, Romano met au point sa conception de l'événement en tant que origine intemporelle de toute temporalité mondaine. La dernière partie de cet article cherche justement à interpréter la naissance comme phénomène événementiel d'ouverture originaire de toute possibilité future pour l'advenant.
Migración interna intermunicipal de Honduras
Authors: Fonseca Manuel Antonio Flores
Published: December 2013

DOI: http://dx.doi.org/10.5377/pdac.v3i0.483Revista Población y Desarrollo: Argonautas y Caminantes, Vol. 3, No. 3, 2008 16-26
La industria maquiladora de exportación y el territorio en Honduras (el caso de Choloma y Villanueva)
Authors: Elvir Rafael Antonio Delgado
Published: December 2013

DOI: http://dx.doi.org/10.5377/pdac.v3i0.486Revista Población y Desarrollo: Argonautas y Caminantes, Vol. 3, No. 3, 2008 40-47
Implementación de un Sistema de Gestión de la Calidad en los Laboratorios del CIRA/UNAN
Authors: García Iris Hurtado
Published: December 2013

El Centro para la Investigación en Recursos Acuáticos de Nicaragua (CIRA/UNAN), desde su fundación ha tenido como visión convertirse en un centro de investigación líder a nivel nacional y regional. Actualmente la globalización demanda que los laboratorios de ensayo demuestren competencia técnicas, lo cual se logra a través del establecimiento de un sistema de gestión de la calidad, que mejore continuamente la capacidad operacional y la competencia técnica del laboratorio. En este contexto, surge la necesidad de establecer e implementar un sistema de gestión de la calidad en el CIRA/UNAN, que asegure su competencia técnica, mediante el apego a la norma ISO/IEC 17025:2005 o su equivalente nacional NTN 04 001 05, por ser el mecanismo internacionalmente aceptado para la demostración de la competencia técnica de los laboratorios. La implementación del sistema de gestión de la calidad en los laboratorios del CIRA/UNAN, se desarrolló en cuatro etapas fundamentales, que consistieron en: Diagnostico situacional del Centro, establecimiento del Sistema de Gestión de la Calidad, Implementación y Mantenimiento del mismo. Para alcanzar el éxito en este proceso, fue necesario el involucramiento y la apropiación del sistema de gestión de la calidad por cada uno de los miembros de la organización, así como el compromiso y apoyo de la dirección del Centro. Durante el establecimiento del sistema de gestión de la calidad, fue necesario adecuar la operatividad del centro a los requisitos establecidos en la Norma ISO/IEC 17025:2005, bajo la consideración; que el sistema de gestión debía facilitar la operatividad del Centro. Un aspecto de suma importancia para alcanzar y mantener el éxito en este proceso ha sido la mejora continua del sistema de gestión de la calidad. De manera que el CIRA/UNAN cuenta con un sólido y completo sistema de gestión de calidad que rige todas las operaciones administrativas y técnicas asociadas a la generación de resultados, proyectos, informes e interpretaciones, Así como el logro de la acreditación de nueve ensayos microbiológicos, lo que posiciono al centro como uno de los más prestigioso centros de investigación a nivel nacional. Palabras claves: Calidad; Acreditación; ISO 17025; laboratorios; CIRA/UNAN DOI: http://dx.doi.org/10.5377/uyc.v5i8.310 Universidad y Ciencia No 8 Año 5 2010 2-7
Calidad y Disponibilidad de los Recursos Hídricos en tres Microcuencuas Costeras del Municipio de Tola, Nicaragua
Authors: Delgado Valeria , Calderón Heyddy , Flores Yelba , Salvatierra Thelma
Published: December 2013

Las actividades económicas, el crecimiento de la población en general; así como los cambios climáticos globales, han aumentado la presión sobre los recursos hídricos en el país. Esto se refleja tanto en una disminución en la disponibilidad, así como en la pérdida de calidad de estos recursos. En consecuencia, los gobiernos municipales han formado alianzas estratégicas con organismos internacionales e instituciones académicas para producir información base necesaria para la creación y ejecución de planes de ordenamiento territorial, a fin de planificar futuras demandas de agua. El desarrollo turístico en la franja costera del Municipio de Tola ha generado cambios en el uso del suelo, desprotección de las zonas de recarga de los acuíferos, posible riesgo de intrusión marina por el bombeo excesivo en la zona costera, y ha creado problemas con la disposición de residuos sólidos. Los resultados indican que hay disponibilidad de agua, tanto superficial como subterránea en las tres microcuencas costeras estudiadas; sin embargo su calidad se ha afectado por la presencia de heces fecales en las aguas de los pozos y por residuos de carbamatos en los ríos. El Índice Biótico de Familias de Hilsenhoff arrojó que el agua es relativamente mala en la parte alta y media de las 3 microcuencas. Fue identificada una especie nueva para el Pacífico Sur de Nicaragua (Theodoxus sp.) y una reportada por primera vez en 1972 en San Juan del Sur (Trinectes fonsecensis). Aunque el agua está disponible en cantidad, su calidad restringe su uso para consumo humano; por lo que es necesario concientizar a la población del municipio en cuanto a la protección, limpieza y uso adecuado de los recursos hídricos.DOI: http://dx.doi.org/10.5377/uyc.v5i8.314Universidad y Ciencia No 8 Año 5 2010 13-21
Recopilación del conocimiento oral de la lengua y cultura garífunas
Authors: Álvarez María Dolores , Montenegro Bayardo Gámez
Published: December 2013

El presente estudio trata de las tradiciones que configuran la identidad cultural de los garífunas/ garinagu asentados actualmente en el territorio nicaragüense y tiene como finalidad apoyar a la revitalización de su lengua y cultura. Con esta investigación se confirma la existencia, en esta comunidad, de portadoras y portadores activos que contribuyen a la recopilación del conocimiento oral. Con ellos se aborda temas como: alimentación, vida cotidiana, juegos infantiles, organización social, relaciones de parentesco, economía, educación, fiestas y rituales, instrumentos musicales, manifestaciones artísticas, medicina tradicional, migraciones y viviendas. Garífunas nani iwanka laka bara bila nani aisinka laka ba wahbi ulbi sakaia. Naha stadika munan nara aisisa, Garífunas/Garinagu witin nani Blasi pyua wina nahki ai iwanka natka nani kanba dukiara, witin nani naha minit iwi banghwisa Nikarawa tasbaiara bara luki banghwisa ai iwanka natka nani bara ai bila aisanka naniba kli buki ai kainara brih waia. Naha stadika munan nara kaikan witin nani ba rait banghwisa, naha tawankara, uplika nani sutba pain raya banghwisa, tabaiki banghwisa ai bila aisanka naniba kli buki ai kainara brih waia ba. Witin nani aikuki aisi kaikan, plun nani dukiara, yu banira ai iwanka laka nani, tuktan pulanka nani, tawan asla takanka, ai uplika nani wal iwanka laka, lalah lainkara, kul lainkara, piesta lilika nani bara pulanka nani, Miusik bin dauki nani dukia, ai layanka nani, ai saikaia nani, anira impaki banghwiba bara ai watla nani laka. Garifunas balna ampat yalalahwa lani dawak ampat yulbabauwa kidi lani balna bitik laihwi ulwi yakna atnin Adika tadi munna akat yulwi, Garifunas/Garinagu witingna sara puyuni kaupak ampat yalalahwada bang kidi yulni lani balna, witingna warminit yalalahna bang ki Nikarawa sauni kau witingna kukulwi ampat alas lani kat yalahnin lani duduwa kidi dawak ampat yulbabauwa lani balna bitik kidi baisa yamni yayamwi tanit kau duwi uinin. Adika tadi mumunna puyuni tatalna witingna kidi ramh sanka bang kidika, adika tawanni akat, witingna bitik kidi yamni sanka bang kidika yulni, ramh kukulwi alas lani kat yalahnin lani duduwa kidi dawak ampat yulbabauwa lani balna bitik kidi baisa yamni yayamwi tanit kau duwi uinin kidika. Witingna balna karak yulbauwi tatalna, plun kasnin yulni, alas lani kat yalahnin lani, walabis balna yakikisda lani, aslah kaluduhnin lani, muih balna karak ampat yalalahwa kidi lani, lalah ninin kau, kul sinsni lani yulni, piesta alasna duduwa dawak yakikisdinin lani, miusik bin yayamwa kidi yulni, ampat lawana aiwawanka kidi lani, sinika balna lani, ankat uiwa yulni dawak unina yulni bik.DOI: http://dx.doi.org/10.5377/wani.v59i0.258Wani No.59 2009 pp.50-65
Normalização EMG: considerações da literatura para avaliação da função muscular
Authors: Silva Jr. Rubens Alexandre da
Published: December 2013

Introdução: Diferentes fatores intrínsecos e extrínsecos influenciam a medida de atividade elétrica muscular por meio da eletromiografia (EMG). Para minimizar este efeito, a normalização da EMG é recomendada. Entretanto, pouco se sabe sobre as vantagens e desvantagens de cada método de normalização para uso em diferentes pacientes (sintomáticos e assintomáticos). Objetivos: Revisar e discutir os principais métodos de normalização do sinal da EMG para avaliação da função motora em diferentes sujeitos. Métodos: Incluíram-se artigos publicados, desde 1984, constantes na base de dados Medline. Dezessete estudos, sendo dois com pacientes sintomáticos, e dois, de revisão, foram selecionados para revisão crítica. Conclusão: A escolha de uma técnica de normalização da EMG é com base na variabilidade entre e intra-indivíduos. Um método recomendado para reduzir a variabilidade biológica é aquele com base numa contração voluntária submáxima como referência no processo de normalização. Entretanto, este não considera a capacidade máxima muscular do indivíduo para execução de uma atividade motora.
Book Series in Mathematics Education: An Overview of a Growing Resource
Authors: Hwang Stephen , Cai Jinfa
Published: December 2013

Mathematics education has existed as an independent field of research for over a century. Although young compared with some other domains of research, mathematics education research has nevertheless developed into a fertile and active discipline. In particular, the last 40 years have seen a rapid expansion of output from a growing body of mathematics education researchers. Indeed, the productivity of mathematics education researchers working in a host of subdomains has encouraged the development of a wide variety of research journals (Cai, 2010). The field has clearly expanded beyond a small handful of key journals for disseminating research findings. At the same time, books and monographs on mathematics education have also long been staple venues for published research.
Interpreting the South Flats Earthwork (20MU2): Insights Gained from Geophysical Surveys
Authors: GAFF DONALD , SHERROD LAURA , BRASHLER JANET G.
Published: December 2013

Michigan's prehistoric earthen enclosures are among the least understood archaeological sites in the state. This paper explores the function of the South Flats Earthwork (20MU2) using remote sensing strategies to reveal aspects of its internal structure not available through excavation. Ground penetrating radar and magnetometry were employed to explore this fragile archaeological site. Results, coupled with excavation data, suggest that South Flats was the work of a small-scale society and a locus of storage and food exchange through kin ties.
Influence of precipitation events on phytoplankton biomass in coastal waters of the eastern United States
Authors: Kim Tae‐Wook , Najjar Raymond G. , Lee Kitack
Published: December 2013

Precipitation over the ocean surface in the vicinity of industrialized and populated coastlines can increase the ocean nitrate concentration and consequently enhance ocean primary productivity. Using satellite data and a meteorological reanalysis product, we evaluated the impact of precipitation events on the chlorophyll a concentration in coastal and offshore waters located downwind of the eastern United States. We found that in low‐nutrient areas (defined as having nitrate concentrations < 1 μM) precipitation events were associated with increased levels of chlorophyll a (up to approximately 15%), but in high‐nutrient areas (nitrate concentrations > 1 μM) they were associated with decreased levels. These contrasting responses of chlorophyll a concentration to precipitation were attributed to the correlation of precipitation with wind speed and to other factors (nutrients and light) limiting phytoplankton growth. Increases in wind speed accompanied by precipitation events typically deepen the mixed layer, which can entrain additional nutrients into the mixed layer but simultaneously reduce light availability. We suggest that in nutrient‐depleted areas (south of 36°N) the added nutrients were a dominant factor increasing the chlorophyll a concentration, whereas in the nutrient‐replete areas (north of 36°N), where phytoplankton growth was light limited, reduced light availability was the dominant factor determining reduced chlorophyll a concentration. Our results indicate that an increase in wind speed accompanied by precipitation events was a major contributor to the observed changes in chlorophyll a concentration during wet days, whereas the wet deposition of pollutant nitrogen slightly increased the chlorophyll a concentration (< 5%) only in nutrient‐depleted areas.
Isotropic thaw subsidence in undisturbed permafrost landscapes
Authors: Shiklomanov Nikolay I. , Streletskiy Dmitry A. , Little Jonathon D. , Nelson Frederick E.
Published: December 2013

Observations in undisturbed terrain within some regions of the Arctic reveal limited correlation between increasing air temperature and the thickness of the seasonally thawed layer above ice‐rich permafrost. Here we describe landscape‐scale, thaw‐induced subsidence lacking the topographic contrasts associated with thermokarst terrain. A high‐resolution, 11 year record of temperature and vertical movement at the ground surface from contrasting physiographic regions of northern Alaska, obtained with differential global positioning systems technology, indicates that thaw of an ice‐rich layer at the top of permafrost has produced decimeter‐scale subsidence extending over the entire landscapes. Without specialized observation techniques the subsidence is not apparent to observers at the surface. This “isotropic thaw subsidence” explains the apparent stability of active layer thickness records from some landscapes of northern Alaska, despite warming near‐surface air temperatures. Integrated over extensive regions, it may be responsible for thawing large volumes of carbon‐rich substrate and could have negative impacts on infrastructure.
Diagnosing the warming of the Northeastern U.S. Coastal Ocean in 2012: A linkage between the atmospheric jet stream variability and ocean response
Authors: Chen Ke , Gawarkiewicz Glen G. , Lentz Steven J. , Bane John M.
Published: December 2013

The temperature in the coastal ocean off the northeastern U.S. during the first half of 2012 was anomalously warm, and this resulted in major impacts on the marine ecosystem and commercial fisheries. Understanding the spatiotemporal characteristics of the warming and its underlying dynamical processes is important for improving ecosystem management. Here, we show that the warming in the first half of 2012 was systematic from the Gulf of Maine to Cape Hatteras. Moreover, the warm anomalies extended through the water column, and the local temperature change of shelf water in the Middle Atlantic Bight was largely balanced by the atmospheric heat flux. The anomalous atmospheric jet stream position induced smaller heat loss from the ocean and caused a much slower cooling rate in late autumn and early winter of 2011–2012. Strong jet stream intraseasonal oscillations in the first half of 2012 systematically increased the warm anomalies over the continental shelf. Despite the importance of advection in prior northeastern U.S. continental shelf interannual temperature anomalies, our analyses show that much of the 2012 warming event was attributed to local warming from the atmosphere.
Hydrological evaluation of the Noah‐MP land surface model for the Mississippi River Basin
Authors: Cai Xitian , Yang Zong‐Liang , David Cédric H. , Niu Guo‐Yue , Rodell Matthew
Published: December 2013

This study evaluates regional‐scale hydrological simulations of the newly developed community Noah land surface model (LSM) with multiparameterization options (Noah‐MP). The model is configured for the Mississippi River Basin and driven by the North American Land Data Assimilation System Phase 2 atmospheric forcing at 1/8° resolution. The simulations are compared with various observational data sets, including the U.S. Geological Survey streamflow and groundwater data, the AmeriFlux tower micrometeorological evapotranspiration (ET) measurements, the Soil Climate Analysis Network (SCAN)‐observed soil moisture data, and the Gravity Recovery and Climate Experiment satellite‐derived terrestrial water storage (TWS) anomaly data. Compared with these observations and to the baseline Noah LSM simulations, Noah‐MP shows significant improvement in hydrological modeling for major hydrological variables (runoff, groundwater, ET, soil moisture, and TWS), which is very likely due to the incorporation of some major improvements into Noah‐MP, particularly an unconfined aquifer storage layer for groundwater dynamics and an interactive vegetation canopy for dynamic leaf phenology. Noah‐MP produces soil moisture values consistent with the SCAN observations for the top two soil layers (0–10 cm and 10–40 cm), indicating its great potential to be used in studying land‐atmosphere coupling. In addition, the simulated groundwater spatial patterns are comparable to observations; however, the inclusion of groundwater in Noah‐MP requires a longer spin‐up time (34 years for the entire study domain). Runoff simulation is highly sensitive to three parameters: the surface dryness factor (α), the saturated hydraulic conductivity (k), and the saturated soil moisture (θmax).
Multiple migmatite events and cooling from granulite facies metamorphism within the Famatina arc margin of northwest Argentina
Authors: Mulcahy Sean R. , Roeske Sarah M. , McClelland William C. , Ellis Joshua R. , Jourdan Fred , Renne Paul R. , Vervoort Jeffrey D. , Vujovich Graciela I.
Published: December 2013

The Famatina margin records an orogenic cycle of convergence, metamorphism, magmatism, and extension related to the accretion of the allochthonous Precordillera terrane. New structural, petrologic, and geochronologic data from the Loma de Las Chacras region demonstrate two distinct episodes of lower crustal migmatization. The first event preserves a counterclockwise pressure‐temperature path in kyanite‐K‐feldspar pelitic migmatites that resulted in lower crustal migmatization via muscovite dehydration melting at ∼12 kbar and 868°C at 461 ±1.7 Ma. The shape of the pressure temperature path and timing of metamorphism are similar to those of regional midcrustal granulites and suggest pervasive Ordovician migmatization throughout the Famatina margin. One‐dimensional thermal modeling coupled with regional isotopic data suggests Ordovician melts remained at temperatures above their solidus for 20–30 Ma following peak granulite facies metamorphism, throughout a time period marked by regional oblique convergence. The onset of synconvergent extension occurred only after regional migmatites cooled beneath their solidus and was synchronous with the cessation of Precordillera terrane accretion at ∼436 Ma. The second migmatite event was regionally localized and occurred at ∼700°C and 12 kbar between 411 and 407 Ma via vapor saturated melting of muscovite. Migmatization was synchronous with extension, exhumation, and strike‐slip deformation that likely resulted from a change in the plate boundary configuration related to the convergence and collision of the Chilenia terrane.
In‐Vehicle Sensors
Authors: Niewels Frank , Knoop Steffen , Jordan Rüdiger , Michalke Thomas
Published: December 2013

This chapter provides an overview of common in‐vehicle sensor technologies (inertial sensors, radar, sonar, and video) and their application in driver assistance systems.
Group sparse RLS algorithms
Authors: Eksioglu Ender M.
Published: December 2013

Group sparsity is one of the important signal priors for regularization of inverse problems. Sparsity with group structure is encountered in numerous applications. However, despite the abundance of sparsity‐based adaptive algorithms, attempts at group sparse adaptive methods are very scarce. In this paper, we introduce novel recursive least squares (RLS) adaptive algorithms regularized via penalty functions, which promote group sparsity. We present a new analytic approximation forℓp,0norm to utilize it as a group sparse regularizer. Simulation results confirm the improved performance of the new group sparse algorithms over regular and sparse RLS algorithms when group sparse structure is present. Copyright © 2013 John Wiley & Sons, Ltd.
We Want Our Photons Back: Simple Nanostructures for White Organic Light‐Emitting Diode Outcoupling
Authors: Kim Yong Hyun , Lee Jonghee , Kim Won Mok , Fuchs Cornelius , Hofmann Simone , Chang Hong‐Wei , Gather Malte C. , Müller‐Meskamp Lars , Leo Karl
Published: December 2013

Conventional planar organic light‐emitting diodes (OLEDs) suffer from poor light extraction due to the total internal reflection at the waveguided interfaces. Therefore, the development of efficient light extraction structures is of great necessity and significance to realize practical applications in large area and cost‐effective light sources. In this paper, a high‐performance internal light outcoupling system for white OLEDs with spontaneously formed metal oxide nanostructures is developed. The fabrication process of the outcoupling system is simple and can be scaled to large area manufacturing. The enhancement of external quantum efficiency in white OLEDs comprising the outcoupling system reaches a factor of 1.7, and it is further increased to 2.9 when a hemispherical lens is employed. Together with the improvement of light extraction, excellent color stability over broad viewing angles is achieved.
Nickel‐Catalyzed Coupling of Fluoroarenes and Amines
Authors: Zhu Feng , Wang Zhong‐Xia
Published: December 2013

The combination of bis(cyclooctadiene)nickel [Ni(COD)2] and 1,3‐bis(2,6‐diisopropylphenyl)imidazol‐2‐ylidene hydrochloride (IPr⋅HCl) effectively catalyzes coupling of fluoroarenes with amines in the presence of sodium tert‐butoxide (t‐BuONa). Activated, unactivated and deactivated fluoroarenes as well as fluoropyridines can react with cyclic or acyclic aliphatic amines. The reactions tolerate various functional groups in the fluorides including PhC(O), C(O)NEt2, CF3, OMe and vinyl groups.

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Effects of excluded volume and hydrodynamic interactions on the behavior of isolated bead‐rod polymer chains in shearing flow
Authors: Dalal Indranil Saha , Hsieh Chih‐Chen , Albaugh Alex , Larson Ronald G.
Published: December 2013

A detailed study of the effects of hydrodynamic interaction (HI) and excluded volume (EV), on isolated bead‐rod chains in shear flows, where the “rods” are mimicked by stiff Fraenkel springs is presented. It is observed that the deformation behavior at weak and intermediate shear rates is qualitatively similar to that observed for polymer chains in the absence of EV and HI, while that at high‐shear rates is sensitive to modeling details and chain resolution. Our simulations with varying degrees of resolution reveal universality in chain behavior in the presence of EV (without HI), while the onset of the transition to a compressed chain in the presence of HI (without EV) shifts to higher shear rates with increasing chain resolution. The results also highlight the success of the bead‐spring models in predicting the chain behavior in shear flows in the presence of HI, when the HI parameter is appropriately chosen. © 2014 American Institute of Chemical Engineers AIChE J, 60: 1400–1412, 2014
Comparing the utility of homogeneous subtypes of cocaine use and related behaviors with DSM‐IV cocaine dependence as traits for genetic association analysis
Authors: Bi Jinbo , Gelernter Joel , Sun Jiangwen , Kranzler Henry R.
Published: December 2013

Because DSM‐IV cocaine dependence (CD) is heterogeneous, it is not an optimal phenotype to identify genetic variation contributing to risk for cocaine use and related behaviors (CRBs). We used a cluster analytic method to differentiate homogeneous, highly heritable subtypes of CRBs and to compare their utility with that of the DSM‐IV CD as traits for genetic association analysis. Clinical features of CRBs and co‐occurring disorders were obtained via a poly‐diagnostic interview administered to 9,965 participants in genetic studies of substance dependence. A subsample of subjects (N = 3,443) were genotyped for 1,350 single nucleotide polymorphisms (SNPs) selected from 130 candidate genes related to addiction. Cluster analysis of clinical features of the sample yielded five subgroups, two of which were characterized by heavy cocaine use and high heritability: a heavy cocaine use, infrequent intravenous injection group and an early‐onset, heavy cocaine use, high comorbidity group. The utility of these traits was compared with the CD diagnosis through association testing of 2,320 affected subjects and 480 cocaine‐exposed controls. Analyses examined both single SNP (main) and SNP–SNP interaction (epistatic) effects, separately for African‐Americans and European‐Americans. The two derived subtypes showed more significant P values for 6 of 8 main effects and 7 of 8 epistatic effects. Variants in the CLOCK gene were significantly associated with the heavy cocaine use, infrequent intravenous injection group, but not with the DSM‐IV diagnosis of CD. These results support the utility of subtypes based on CRBs to detect risk variants for cocaine addiction. © 2013 Wiley Periodicals, Inc.
Copper‐Catalyzed Trifluoromethylation‐Initiated Radical Oxidative Annulation toward Oxindoles
Authors: Lu Qingquan , Liu Chao , Peng Pan , Liu Zhiliang , Fu Lijun , Huang Jinguo , Lei Aiwen
Published: December 2013

A copper‐catalyzed radical oxidative trifluoromethylation and arylation of electron‐withdrawing alkenes has been developed, in which economical sodium trifluoromethanesulfinate is used as the CF3 source. A preliminary kinetic investigation indicated that the generation of CF3 radicals under the mild conditions might be a facile process.
Serendipitous Discovery of a Potent Influenza Virus A Neuraminidase Inhibitor
Authors: Mohan Sankar , Kerry Philip S. , Bance Nicole , Niikura Masahiro , Pinto B. Mario
Published: December 2013

We have previously reported a potent neuraminidase inhibitor that comprises a carbocyclic analogue of zanamivir in which the hydrophilic glycerol side chain is replaced by the hydrophobic 3‐pentyloxy group of oseltamivir. This hybrid inhibitor showed excellent inhibitory properties in the neuraminidase inhibition assay (Ki=0.46 nM; Ki (zanamivir)=0.16 nM) and in the viral replication inhibition assay in cell culture at 10−8 M. As part of this lead optimization, we now report a novel spirolactam that shows comparable inhibitory activity in the cell culture assay to that of our lead compound at 10−7 M. The compound was discovered serendipitously during the attempted synthesis of the isothiourea derivative of the original candidate. The X‐ray crystal structure of the spirolactam in complex with the N8 subtype neuraminidase offers insight into the mode of inhibition.
Oxidative Addition of 2‐Halogenoazoles—Direct Synthesis of Palladium(II) Complexes Bearing Protic NH,NH‐Functionalized NHC Ligands
Authors: Das Rajorshi , Daniliuc Constantin G. , Hahn F. Ekkehardt
Published: December 2013

The chemistry of N‐heterocyclic carbenes (NHCs) is dominated by N,N′‐dialkylated or ‐diarylated derivatives. Such NHC ligands are normally obtained by C2‐deprotonation of azolium cations or by reductive elimination from azol‐2‐thiones. A simple one‐step procedure is described that leads to complexes with NH,NH‐functionalized NHC ligands by the oxidative addition of 2‐halogenoazoles to complexes of zero‐valent transition metals.
Synthesis and Catalytic Activities of Porphyrin‐Based PCP Pincer Complexes
Authors: Fujimoto Keisuke , Yoneda Tomoki , Yorimitsu Hideki , Osuka Atsuhiro
Published: December 2013

2,18‐Bis(diphenylphosphino)porphyrins undergo peripheral cyclometalation with group 10 transition‐metal salts to afford the corresponding porphyrin‐based PCP pincer complexes. The porphyrinic plane and the PCP‐pincer unit are apparently coplanar, with small strain. The catalytic activities of the porphyrin‐based pincer complexes at the periphery were investigated in the allylation of benzaldehyde with allylstannane and in the 1,4‐reduction of chalcone to discover the electronic interplay between the inner metal and the outer metal in catalysis.
NHC‐Pd complex‐catalyzed double carbonylation of aryl iodides with secondary amines to α‐keto amides
Authors: Zheng Shuzhan , Wang Yan , Zhang Chunyan , Liu Jianhua , Xia Chungu
Published: December 2013

A series of palladium–NHC compounds were prepared and their catalytic activity in the double carbonylation of aryl iodides to synthesize α‐keto amides were examined. Palladium complexes bearing mixed NHC–phosphine exhibited high efficiency for the double carbonylation reaction. The effects of different solvents, base, temperature, carbon monoxide (CO), pressure, various amine and aryl iodides were investigated. Both electron‐rich and electron‐deficient aryl iodides afforded the corresponding substituted α‐keto amides in moderate to good yields. A possible mechanism was also proposed. Copyright © 2013 John Wiley & Sons, Ltd.
Trajectory Tracking Control of a PVTOL Aircraft Based on Linear Algebra Theory
Authors: Gandolfo D. , Rosales C. , Patiño D. , Scaglia G. , Jordan M.
Published: December 2013

In this work, a trajectory tracking control design is proposed for the planar vertical takeoff and landing (PVTOL) aircraft using linear algebra theory. The resulting control law is implemented easily since the equation to be solved is not complex. The tracking is achieved providing convergence of the tracking errors to zero, and simulation results show the good performance of the proposed controller.
Synthesis and photoluminescence properties of Sm3+‐doped YAl3(BO3)4phosphor
Authors: Satheesh Kumar R. , Ponnusamy V. , Jose M. T.
Published: December 2013

A near ultraviolet excitable phosphor based on Sm3+‐doped YAl3(BO3)4has been synthesized by modified solid‐state reaction at 1000°C. The phase purity and photoluminescence (PL) behavior of the phosphor are studied in detail using the powder X‐ray diffraction technique and PL measurements. X‐ray diffraction reveals that the phase purity of YAl3(BO3)4critically depends upon the boric acid concentration. The phosphor has strong excitation at 406 nm in the near ultraviolet region (350–420 nm) and its emission peaks were monitored at 564, 599 and 643 nm. Further, detailed PL analysis demonstrates that the substitution of Sm3+ions at sites of Y3+and Al3+ions enhances the PL efficiency of the phosphor appreciably. First, the PL efficiency of YAl3(BO3)4:Sm3+was compared with commercial (Y,Gd)BO3:Eu3+red phosphor. The Fourier transform infrared study provides essential information regarding the change in metal–oxygen bond vibrations of the phosphor. The morphology of the phosphor was investigated through scanning electron microscopy, which reveals that the phosphor possessed distorted spherical and rectangular shapes with average grain sizes in the range 0.5–1 µm. Copyright © 2013 John Wiley & Sons, Ltd.