bluuebunny/crossref_metadata_2025 huggingface dataset:
Placement familial et rencontres médiatisées dans une perspective systémique
Authors: Legendre Christian
Published: February 2014

Le placement familial constitue de fait un contexte particulier de multi-parentalité, à savoir une double parentalité avec des liens de filiation et des liens d’affiliation. Dans certaines situations particulièrement délicates, les juges ordonnent que les rencontres parents-enfants soient médiatisées par des professionnels de l’enfance. C’est un exercice délicat. Sachant que nombre d’études catamnestiques montrent que l’avenir des enfants placés est souvent sombre, l’auteur fait l’hypothèse que des croyances et les pratiques habituelles qui se réfèrent à ces croyances n’aident pas les professionnels à problématiser la question de l’appartenance de l’enfant ni celle des attachements réciproques, d’une façon qui permette que des processus thérapeutiques soient activés. Mais qu’au contraire, ces pratiques obèrent la possibilité qu’ils puissent advenir. En s’appuyant sur l’approche systémique, il propose une nouvelle définition de la parentalité et une modélisation du travail lors des rencontres médiatisées (négociation, contractualisation, projet individualisé), pour tendre vers la création d’un système qui ouvre la possibilité d’une double parentalité complémentaire offrant à l’enfant placé une suppléance familiale partagée et soutenante, et si possible temporaire.
La fin d'INCANT : la transition de la recherche à la pratique clinique
Authors: Har Alexandre , Bonnaire Céline
Published: February 2014

La recherche INCANT (International Cannabis Need of Treatment) a bénéficié d’un statut un peu à part dans le paysage de la recherche en thérapie familiale. L’objectif principal de cette étude était de comparer, dans le cadre d’un essai thérapeutique standardisé, randomisé et longitudinal, l’efficacité d’une méthode de thérapie familiale (MDFT) par rapport à la thérapie habituelle (TAU) sur la réduction de la consommation de cannabis chez des adolescents présentant un usage abusif et/ou une dépendance à cette substance. Dans cet article, nous explorons la phase de transition entre la fin de la recherche et la mise en place de la pratique clinique de la MDFT en institution. Quels furent les enjeux rencontrés dans la formation des premières et secondes générations de thérapeutes MDFT ? Quelles sont les questions soulevées par la pratique d’une thérapie familiale de type evidence based therapy dans la relation de supervision ?
Sobre la dimensión persuasiva de la máxima y del refrán en El Quijote y su contribución a la configuración del «efecto-personaje»
Authors: Herrero Cecilia Juan
Published: February 2014

Con este estudio tratamos de poner de relieve la dimensión persuasiva de la máxima y del refrán en El Quijote de Cervantes relacionando el recurso a la máxima y al refrán con las voces de don Quijote y Sancho como una manifestación significativa de su manera de pensar y de enfocar la realidad de la vida y del mundo, y como una estrategia eficaz que contribuye a producir en la mente del lector el «efecto-personaje». El empleo de la máxima o de la reflexión moral por don Quijote manifiesta un pensamiento personal de alcance universal relacionado con una sabiduría humanista que contrasta con su locura caballeresca. Sancho, por su parte, recurriendo a la sabiduría popular de los refranes para defender la lógica del sentido común, ofrece la imagen de un espíritu perspicaz y sincero. Entre ambos personajes se irá produciendo una influencia mutua que implica una transformación y una especial armonía entre contrarios.
Reconsideración de la poesía cervantina: los defectos métricos y estilísticos de Cervantes
Authors: Olay Valdés Rodrigo
Published: February 2014

Cervantes ha venido siendo considerado como un poeta mediocre y poco dotado técnicamente. En tres textos clásicos de gran influencia aún hoy, Ricardo Rojas, Francisco Rodríguez Marín y Gerardo Diego se refirieron al mal oído de Cervantes y a su torpeza como versificador, lo que ha llegado a ser un verdadero lugar común de la crítica cervantina. Recientes intentos de revaloración de la poesía de Cervantes han pasado por alto esta dura serie de reproches. Hoy examinados, muchos de los supuestos errores técnicos que tradicionalmente se han imputado a Cervantes no son ya tales las más de las veces. Es hora de revisar si verdaderamente fue Cervantes un poeta tan poco dotado técnicamente.
«A la juventud española», don Quijote dreyfussard
Authors: Ramírez Martín Virginia
Published: February 2014

En 1898 la prensa española ocupa parte de sus páginas con un asunto de relevancia internacional: el caso Dreyfus. Entre la cobertura prestada al asunto por todas las cabeceras destaca la hecha por el semanario satírico madrileño Don Quijote; tanto es así que desde su dirección se llega a impulsar un movimiento de adhesión a Zola que tiene por fin la recogida de firmas que hagan saber al literato francés que España está de su lado. Dicha iniciativa se completa con un llamamiento a la juventud española que se ilustra con una caricatura quijotesca. El personaje cervantino encarna la defensa de la justicia y logra difundir en la crisis del fin de siglo español la imagen del hidalgo caballero que se había forjado en el imaginario español, como un cruzado luchando a favor de una noble causa, convirtiendo así a Don Quijote en un dreyfussard más.
Core-Based GRASP for Delay-Constrained Group Communications
Authors: Lukač Zrinka , Laguna Manuel
Published: February 2014

The recent development in network multimedia technology has created numerous real-time multimedia applications where the Quality-of-Service (QoS) requirements are quite rigorous. This has made multicasting under QoS constraints one of the most prominent routing problems. The authors consider the problem of the efficient delivery of data stream to receivers for multi-source communication groups. Efficiency in this context means to minimize cost while meeting bounds on the end-to-end delay of the application. The authors adopt the multi-core approach and utilize SPAN (Karaman and Hassane, 2007)—a core-based framework for multi-source group applications — as the basis to develop greedy randomized adaptive search procedures (GRASP) for the associated constrained cost minimization problem. The procedures are tested in asymmetric networks and computational results show that they consistently outperform their counterparts in the literature.
Extracting Visually Presented Element Relationships from Web Documents
Authors: Burget Radek , Smrz Pavel
Published: February 2014

Many documents in the World Wide Web present structured information that consists of multiple pieces of data with certain relationships among them. Although it is usually not difficult to identify the individual data values in the document text, their relationships are often not explicitly described in the document content. They are expressed by visual presentation of the document content that is expected to be interpreted by a human reader. In this paper, the authors propose a formal generic model of logical relationships in a document based on an interpretation of visual presentation patterns in the documents. The model describes the visually expressed relationships between individual parts of the contents independently of the document format and the particular way of presentation. Therefore, it can be used as an appropriate document model in many information retrieval or extraction applications. The authors formally define the model, the authors introduce a method of extracting the relationships between the content parts based on the visual presentation analysis and the authors discuss the expected applications. The authors also present a new dataset consisting of programmes of conferences and other scientific events and the authors discuss its suitability for the task in hand. Finally, the authors use the dataset to evaluate results of the implemented system.
New Results in Development of Methods for Optimization of Heat Supply System Parameters and Their Software Implementation
Authors: Barakhtenko E. A. , Oshchepkova T. B. , Sokolov D. V. , Stennikov V. A.
Published: February 2014

Modern practice of solving the problems of heat supply system design generates the need to solve the problem of choosing optimal parameters for a considerable set of equipment. The problem of choosing optimal parameters involves determining the diameters of new heat pipelines, searching for the methods to reconstruct existing network sections, and choosing the pressure heads of pumping stations and their sites. To solve this problem the authors suggest a dynamic programming method for optimization of branched networks and a multiloop optimization method for calculation of loop networks, both being developed in the theory of hydraulic circuits. The paper presents new versions of algorithms for the implementation of these methods and describes their capabilities. These algorithms are implemented in the software package SOSNA-M. This software was developed on the basis of a methodological approach created to develop algorithms and methods for optimization of heat supply system parameters, flexibly control the computational process, optimize heat supply system parameters on a feasible set of equipment and improve the types of reconstruction of the existing components.
Mapping Web Interactivity
Authors: Wang Kevin Y , Lee Hyung Min , Atkin David , Kim Cheonsoo
Published: February 2014

This paper explores the use of interactive communication and dialogic relationship building strategies on political campaign Web sites. In contrast to presidential races that often feature substantially more sophisticated campaign Web sites, congressional candidates’ ability and willingness to use the Web as an electioneering tool has varied greatly. The present research sought to address two broad research questions: 1) how candidates from the same electoral districts used their Web sites during the 2006 and 2010 congressional elections; and 2) to what extent could several candidate and district level variables explain the differences in Web utilization. A typology was proposed to examine the first question, while content analysis was performed to collect empirical data that addressed the second question. Results indicate that while the use of interactive Web strategies may be concentrated among candidates with certain characteristics in 2006, the adoption of social media in political campaigns has trickled down from the presidential level, and that interactive tools have become a norm in the 2010 congressional election, with virtually no observable differences emerging among candidates. Theoretical and practical implication for online political public relations is discussed.
The Role of Website Features in Creating Loyalty
Authors: Bilgihan Anil , Sukhu Anupama , Kandampully Jay
Published: February 2014

This study integrates shopping value dimensions and consumers’ commitment to a theoretical model to understand consumer loyalty to e-shopping. E-commerce is established as an efficient sales platform for travel and hospitality vendors. However, extant literature found that it is difficult to attract new customers and retain existing customers in e-commerce. This paper investigates the antecedents of customer loyalty in e-commerce. An online survey with (n=520) was conducted with randomly selected US consumers. A structural equation model reveals that hedonic and utilitarian shopping values determine affective and calculative commitment of e-shoppers which in turn influence consumers’ loyalty towards e-shopping. This study contributes to the present literature and provides important implication towards e-tailers and website developers. It is important to fulfill e-shoppers’ hedonic and utilitarian needs to gain e-loyalty. Web based hospitality service offerings should provide a convenient and pleasing online environment to gain consumer e-loyalty.
Web Portals for Financial Analytics
Authors: Yap Alexander Y.
Published: February 2014

As more investors and traders globally manage their own stock portfolio without the help of human brokers, there is an increasing need to acquire and use financial knowledge and financial data analytics to ensure that a self-maintained financial portfolio is soundly managed. There are a growing number of special web portals that provide financial analytics services for investors and traders who demand detailed analyses of their stocks and other financial derivatives. The objective of this paper is to examine how end-users value the overall usefulness of web portals that provide financial analytics services and capabilities. This research endeavors to identify different unique features of financial analytics web portals, and ask users which of these features prove to be highly useful for their needs in analyzing when to buy, hold, and sell stocks.
Bilateral Adductor Palsy: A Rare Complication during Routine Surgery
Authors: Rangappa Vidya Bhushan , Ramakrishnan Athira , Ram Raja
Published: February 2014

Recurrent laryngeal nerve (RLN) palsy occurring following thyroidectomy is a known complication. The first thing that comes to the surgeons, mind in a case of bilateral recurrent laryngeal nerve palsy is tracheostomy to secure the airway. But here we present a very interesting and unusual case of bilateral adductor palsy, post total thyroidectomy. We also highlight on the fact that not always the surgeon is to be blamed and there are certain subtle other factors to be aware of.

How to cite this article

Rangappa VB, Ramakrishnan A, Balasubramanya AM, Ram R. Bilateral Adductor Palsy: A Rare Complication during Routine Surgery. World J Endoc Surg 2013;5(3):76-78.
Osteochondroma of the Parapharyngeal Space: A Rare Case Report
Authors: Gupta Ashok K , Gupta Karan , Vaiphei Kim , Kaushal Darwin
Published: February 2014

Extraskeletal osteochondroma in parapharyngeal space is very rare. It is important to note that such a diagnosis be considered when a discrete, ossified mass is localized in soft tissues, even at atypical sites. Its diagnosis is based on radiological and histopathological examination. We should be clinically aware of this benign entity as no malignant transformation or metastasis has been reported. Excision with adequate cuff of tissue is treatment of choice. We did not encounter any case report of osteochondroma in the parapharyngeal space in literature, with our best possible effort.

How to cite this article

Gupta AK, Kaushal D, Gupta K, Vaiphei K. Osteochondroma of the Parapharyngeal Space: A Rare Case Report. Int J Otorhinolaryngol Clin 2013;5(3):142-144.
Papillary Carcinoma of the Thyroglossal Duct Cyst: A Case Report and Review of Literature
Authors: Sood Neena , Munjal Manish , Garg Bhawna , Bhardwaj Vikram
Published: February 2014

Papillary carcinoma arising in thyroglossal cyst is rare and is usually detected on postoperative histopathology after routine Sistrunk operation. Further management is a matter of debate and the choice lies between regular follow-up after Sistrunk operation or total thyroidectomy with or without radioiodine ablation and thyroxine suppression therapy. Here, we present a case of papillary carcinoma of thyroglossal duct cyst in a 26- year-old lady. Papillary carcinoma was detected after a routine Sistrunk operation was done for a seemingly innocuous thyroglossal cyst. A total thyroidectomy was carried 1 week later followed by hormone replacement therapy to suppress serum thyroid-stimulating hormone levels.

How to cite this article

Munjal M, Garg B, Sood N, Bhardwaj V. Papillary Carcinoma of the Thyroglossal Duct Cyst: A Case Report and Review of Literature. Int J Otorhinolaryngol Clin 2013;5(3):148-150.
Auricular Schwannoma: A Rare Presentation
Authors: Sharma Satish Kumar , Raina Rashmi , Gupta Vikas Deep
Published: February 2014

Schwannoma is an extremely rare tumor of auricle. We are presenting a rare case of auricular schwannoma, perhaps the fifth in world literature, with traumatic etiology. Twenty-five years old female presented with swelling left pinna since 6 years following ear piercing. She desires surgery for cosmetic reasons only. Swelling was excised under local anesthesia and sent for histopathological examination. HPE report was suggestive of nerve sheath tumor. No recurrence has reported so far in followup of 9 months period.

How to cite this article

Thakur K, Sharma SK, Raina R, Gupta VD. Auricular Schwannoma: A Rare Presentation. Int J Otorhinolaryngol Clin 2013;5(3):166-168.
Traumatic Arteriovenous Malformation of Cheek: A Case Report and Review of Literature
Authors: Bhandary B Satheesh Kumar , Bhat Vadisha , Aroor Rajeshwary , Shetty Shama
Published: February 2014

Arteriovenous malformations (AVM) are congenital vascular anomalies but are usually first noticed in childhood or adulthood. Head and neck is the most common location for AVM. Extracranial lesions are rare compared to intracranial lesions. The rapid enlargement of the malformation leading to symptoms is usually triggered by trauma or hormonal changes of puberty or pregnancy. Traumatic AVM of the head and neck are very rare. Here we report a case of AVM of cheek in an adult woman developed following a dental treatment. The diagnosis was confirmed by imaging and was treated surgically after angiography and embolization.

How to cite this article

Bhat VS, Aroor R, Bhandary BSK, Shetty S. Traumatic Arteriovenous Malformation of Cheek: A Case Report and Review of Literature. Int J Otorhinolaryngol Clin 2013;5(3):173-177.
Summer Arctic sea ice albedo in CMIP5 models
Authors: Koenigk T. , Devasthale A. , Karlsson K.-G.
Published: February 2014

Abstract. Spatial and temporal variations of summer sea ice albedo over the Arctic are analyzed using an ensemble of historical CMIP5 model simulations. The results are compared to the CLARA-SAL product that is based on long-term satellite observations. The summer sea ice albedo varies substantially among CMIP5 models, and many models show large biases compared to the CLARA-SAL product. Single summer months show an extreme spread of ice albedo among models; July values vary between 0.3 and 0.7 for individual models. The CMIP5 ensemble mean, however, agrees relatively well in the central Arctic but shows too high ice albedo near the ice edges and coasts. In most models, the ice albedo is spatially too uniformly distributed. The summer-to-summer variations seem to be underestimated in many global models, and almost no model is able to reproduce the temporal evolution of ice albedo throughout the summer fully. While the satellite observations indicate the lowest ice albedos during August, the models show minimum values in July and substantially higher values in August. Instead, the June values are often lower in the models than in the satellite observations. This is probably due to too high surface temperatures in June, leading to an early start of the melt season and too cold temperatures in August causing an earlier refreezing in the models. The summer sea ice albedo in the CMIP5 models is strongly governed by surface temperature and snow conditions, particularly during the period of melt onset in early summer and refreezing in late summer. The summer surface net solar radiation of the ice-covered Arctic areas is highly related to the ice albedo in the CMIP5 models. However, the impact of the ice albedo on the sea ice conditions in the CMIP5 models is not clearly visible. This indicates the importance of other Arctic and large-scale processes for the sea ice conditions.
The added value of water isotopic measurements for understanding model biases in simulating the water cycle over Western Siberia
Authors: Gryazin V. , Risi C. , Jouzel J. , Kurita N. , Worden J. , Frankenberg C. , Bastrikov V. , Gribanov K. , Stukova O.
Published: February 2014

Abstract. We evaluate the isotopic composition of water vapor and precipitation simulated by the LMDZ GCM over Siberia using several datasets: TES and GOSAT satellite observations of tropospheric water vapor, GNIP and SNIP precipitation networks, and daily, in-situ measurements of water vapor and precipitation at the Kourovka site in Western Siberia. We use δD vs. humidity diagrams to explore the complementarity of these two variables to interpret model biases in terms of the representation of processes. LMDZ captures the spatial, seasonal and daily variations reasonably well. It systematically overestimates δD in the vapor and precipitation, a bias that is most likely associated with a misrepresentation of air mass origin. The performance of LMDZ is put in the context of other isotopic models from the SWING2 models. There is significant spread among models in the simulation of δD, and of the δD vs. humidity relationship. This confirms that δD brings additional information compared to humidity only. We specifically investigate the added value of water isotopic measurements to interpret the warm and dry bias feature by most GCMs over mid and high latitude continents in summer. LMDZ simulates the strongest dry bias on days when it simulates the strongest enriched bias in δD. The analysis of the slopes in δD vs. humidity diagrams and of processes controlling δD and humidity variations suggests that the cause of the moist bias could be either a problem in the large-scale advection transporting too much dry and warm air from the south, or insufficient surface evaporation.
Impact of optimized mixing heights on simulated regional atmospheric transport of CO2
Authors: Kretschmer R. , Gerbig C. , Karstens U. , Biavati G. , Vermeulen A. , Vogel F. , Hammer S. , Totsche K. U.
Published: February 2014

Abstract. The mixing height (MH) is a crucial parameter in commonly used transport models that proportionally affects air concentrations of trace gases with sources/sinks near the ground and on diurnal scales. Past synthetic data experiments indicated the possibility to improve tracer transport by minimizing errors of simulated MHs. In this paper we evaluate a method to constrain the Langrangian particle dispersion model STILT (Stochastic Time-Inverted Lagrangian Transport) with MH diagnosed from radiosonde profiles using a bulk Richardson method. The same method was used to obtain hourly MHs for the period September/October 2009 from the Weather Research and Forecasting (WRF) model, which covers the European continent at 10 km horizontal resolution. Kriging with External Drift (KED) was applied to estimate optimized MHs from observed and modelled MHs, which were used as input for STILT to assess the impact on CO2 transport. Special care has been taken to account for uncertainty in MH retrieval in this estimation process. MHs and CO2 concentrations were compared to vertical profiles from aircraft in-situ data. We put an emphasis on testing the consistency of estimated MHs to observed vertical mixing of CO2. Modelled CO2 was also compared with continuous measurements made at Cabauw and Heidelberg stations. WRF MHs were significantly biased by ~10–20% during day and ~40–60% during night. Optimized MHs reduced this bias to ~5% with additional slight improvements in random errors. The KED MHs were generally more consistent with observed CO2 mixing. The use of optimized MHs had in general a favourable impact on CO2 transport, with bias reductions of 5–45% (day) and 60–90% (night). This indicates that a large part of the found CO2 model-data mismatch was indeed due to MH errors. Other causes for CO2 mismatch are discussed. Applicability of our method is discussed in the context of CO2 inversions at regional scales.
The impact of extreme summer drought on the short-term carbon coupling of photosynthesis to soil CO2 efflux in a temperate grassland
Authors: Burri S. , Sturm P. , Prechsl U. E. , Knohl A. , Buchmann N.
Published: February 2014

Abstract. Along with predicted climate change, increased risks for summer drought are projected for Central Europe. However, large knowledge gaps exist in terms of how drought events influence the short-term ecosystem carbon cycle. Here, we present results from 13CO2 pulse labeling experiments at an intensively managed lowland grassland in Switzerland. We investigated the effect of extreme summer drought on the short-term coupling of freshly assimilated photosynthates in shoots to roots as well as to soil CO2 efflux. Summer drought was simulated using rainout shelters during two field seasons (2010 and 2011). Soil CO2 efflux and its isotopic composition were measured with custom-built chambers coupled to a quantum cascade laser spectrometer (QCLAS-ISO, Aerodyne Research Inc., MA, USA). During the 90 min pulse labeling experiments, we added 99.9 atom % 13CO2 to the grass sward. In addition to the isotopic analysis of soil CO2 efflux, this label was traced over 31 days into bulk shoots, roots and soil. Drought reduced the incorporation of recently fixed carbon into the shoots, but increased the relative allocation of fresh assimilates below ground compared to the control grasslands. Contrary to our hypothesis, we did not find a change of allocation speed in response to drought. Although drought clearly reduced soil CO2 efflux rates, about 75% of total tracer uptake in control plots was lost via soil CO2 efflux during 19 days after pulse labeling, compared to only about 60% under drought conditions. Thus, the short-term coupling of above- and below-ground processes was reduced in response to summer drought. The occurrence of a natural spring drought in 2011 lead to comparable albeit weaker drought responses increasing the confidence in the generalizability of our findings.
Biogeochemistry of the North Atlantic during oceanic anoxic event 2: role of changes in ocean circulation and phosphorus input
Authors: Ruvalcaba Baroni I. , Topper R. P. M. , van Helmond N. A. G. M. , Brinkhuis H. , Slomp C. P.
Published: February 2014

Abstract. The geological record provides evidence for the periodic occurrence of water column anoxia and formation of organic-rich deposits in the North Atlantic Ocean during the mid-Cretaceous (hereafter called the proto-North Atlantic). Both changes in primary productivity and oceanic circulation likely played a role in the development of the low-oxygen conditions. Several studies suggest that an increased input of phosphorus from land initiated oceanic anoxic events (OAEs). Other proposed mechanisms invoke a vigorous upwelling system and an ocean circulation pattern that acted as a trap for nutrients from the Pacific Ocean. Here, we use a detailed biogeochemical box model for the proto-North Atlantic to analyse under what conditions anoxia could have developed during OAE2 (94 Ma). The model explicitly describes the coupled water, carbon, oxygen and phosphorus cycles for the deep basin and continental shelves. In our simulations, we assume the vigorous water circulation from a recent regional ocean model study. Our model results for pre-OAE2 and OAE2 conditions are compared to sediment records of organic carbon and proxies for photic zone euxinia and bottom water redox conditions (e.g. isorenieratane, carbon/phosphorus ratios). Our results show that a strongly elevated input of phosphorus from rivers and the Pacific Ocean relative to pre-OAE2 conditions is a requirement for the widespread development of low oxygen in the proto-North Atlantic during OAE2. Moreover, anoxia in the proto-North Atlantic is shown to be greatly influenced by the oxygen concentration of Pacific bottom waters. In our model, primary productivity increased significantly upon the transition from pre-OAE2 to OAE2 conditions. Our model captures the regional trends in anoxia as deduced from observations, with euxinia spreading to the northern and eastern shelves but with the most intense euxinia occurring along the southern coast. However, anoxia in the central deep basin is difficult to achieve in the model. This suggests that the ocean circulation used in the model may be too vigorous and/or that anoxia in the proto-North Atlantic was less widespread than previously thought.
The role of mixotrophic protists in the biological carbon pump
Authors: Mitra A. , Flynn K. J. , Burkholder J. M. , Berge T. , Calbet A. , Raven J. A. , Granéli E. , Glibert P. M. , Hansen P. J. , Stoecker D. K. , Thingstad F. , Tillmann U. , Våge S. , Wilken S. , Zubkov M. V.
Published: February 2014

Abstract. The traditional view of the planktonic food web describes consumption of inorganic nutrients by photoautotrophic phytoplankton, which in turn supports zooplankton and ultimately higher trophic levels. Pathways centred on bacteria provide mechanisms for nutrient recycling. This structure lies at the foundation of most models used to explore biogeochemical cycling, functioning of the biological pump, and the impact of climate change on these processes. We suggest an alternative new paradigm, which sees the bulk of the base of this food web supported by protist plankton communities that are mixotrophic – combining phototrophy and phagotrophy within a single cell. The photoautotrophic eukaryotic plankton and their heterotrophic microzooplankton grazers dominate only during the developmental phases of ecosystems (e.g. spring bloom in temperate systems). With their flexible nutrition, mixotrophic protists dominate in more-mature systems (e.g. temperate summer, established eutrophic systems and oligotrophic systems); the more-stable water columns suggested under climate change may also be expected to favour these mixotrophs. We explore how such a predominantly mixotrophic structure affects microbial trophic dynamics and the biological pump. The mixotroph-dominated structure differs fundamentally in its flow of energy and nutrients, with a shortened and potentially more efficient chain from nutrient regeneration to primary production. Furthermore, mixotrophy enables a direct conduit for the support of primary production from bacterial production. We show how the exclusion of an explicit mixotrophic component in studies of the pelagic microbial communities leads to a failure to capture the true dynamics of the carbon flow. In order to prevent a misinterpretation of the full implications of climate change upon biogeochemical cycling and the functioning of the biological pump, we recommend inclusion of multi-nutrient mixotroph models within ecosystem studies.
The impact of climate variation and disturbances on the carbon balance of forests in Hokkaido, Japan
Authors: Hirata R. , Takagi K. , Ito A. , Hirano T. , Saigusa N.
Published: February 2014

Abstract. We evaluated the long-term effect of climate, disturbance, and subsequent recovery on the carbon balance of temperate-boreal forest using the process-based ecosystem model VISIT. The study sites are artificial larch forests, which were planted after clear-cutting of mixed forest, in Hokkaido, Japan. In this study, three experimental simulations were conducted. First, we performed a baseline simulation of carbon dynamics and compared these values with those observed across a wide range of stand ages (old mixed forest and young and middle-aged larch forests). Second, we ran attribution simulations to investigate how disturbance and several climate factors affect long-term carbon fluxes. Third, we analyzed the sensitivity of carbon balance to the amount of disturbance-generated residues. By taking into account seasonal variation in the understory leaf area index, which played an important role especially in the initial stage of recovery, simulated net ecosystem production (NEP), gross primary production, ecosystem respiration, and biomass for the three types of forests were consistent with observed values. The effect of disturbances such as clear-cutting, land-use conversion, and thinning on the long-term trend of NEP was larger than that of climate variation, even several decades after clear-cutting. In contrast, interannual variation in the carbon balance was primarily attributable to climate variation. These findings indicate that disturbance controlled the long-term trend of the carbon balance, whereas climate factors controlled yearly variation in the carbon balance. Among the meteorological factors considered, temperature and precipitation mainly affected NEP and its interannual variation. The carbon balance in the initial post-disturbance period, which is strongly affected by the amount of residues, influenced the subsequent long-term carbon budget, implying the importance of residue management. Consequently, carbon release just after disturbance and the length of the recovery period required to pay back the carbon debt are controlled by the amount of residues.
Carbon cycle uncertainty in the Alaskan Arctic
Authors: Fisher J. B. , Sikka M. , Oechel W. C. , Huntzinger D. N. , Melton J. R. , Koven C. D. , Ahlström A. , Arain A. M. , Baker I. , Chen J. M. , Ciais P. , Davidson C. , Dietze M. , El-Masri B. , Hayes D. , Huntingford C. , Jain A. , Levy P. E. , Lomas M. R. , Poulter B. , Price D. , Sahoo A. K. , Schaefer K. , Tian H. , Tomelleri E. , Verbeeck H. , Viovy N. , Wania R. , Zeng N. , Miller C. E.
Published: February 2014

Abstract. Climate change is leading to a disproportionately large warming in the high northern latitudes, but the magnitude and sign of the future carbon balance of the Arctic are highly uncertain. Using 40 terrestrial biosphere models for Alaska, we provide a baseline of terrestrial carbon cycle structural and parametric uncertainty, defined as the multi-model standard deviation (σ) against the mean (x) for each quantity. Mean annual uncertainty (σ/x) was largest for net ecosystem exchange (NEE) (−0.01± 0.19 kg C m−2 yr−1), then net primary production (NPP) (0.14 ± 0.33 kg C m−2 yr−1), autotrophic respiration (Ra) (0.09 ± 0.20 kg C m−2 yr−1), gross primary production (GPP) (0.22 ± 0.50 kg C m−2 yr−1), ecosystem respiration (Re) (0.23 ± 0.38 kg C m−2 yr−1), CH4 flux (2.52 ± 4.02 g CH4 m−2 yr−1), heterotrophic respiration (Rh) (0.14 ± 0.20 kg C m−2 yr−1), and soil carbon (14.0± 9.2 kg C m−2). The spatial patterns in regional carbon stocks and fluxes varied widely with some models showing NEE for Alaska as a strong carbon sink, others as a strong carbon source, while still others as carbon neutral. Additionally, a feedback (i.e., sensitivity) analysis was conducted of 20th century NEE to CO2 fertilization (β) and climate (γ), which showed that uncertainty in γ was 2x larger than that of β, with neither indicating that the Alaskan Arctic is shifting towards a certain net carbon sink or source. Finally, AmeriFlux data are used at two sites in the Alaskan Arctic to evaluate the regional patterns; observed seasonal NEE was captured within multi-model uncertainty. This assessment of carbon cycle uncertainties may be used as a baseline for the improvement of experimental and modeling activities, as well as a reference for future trajectories in carbon cycling with climate change in the Alaskan Arctic.
Volcanic forcing for climate modeling: a new microphysics-based data set covering years 1600–present
Authors: Arfeuille F. , Weisenstein D. , Mack H. , Rozanov E. , Peter T. , Brönnimann S.
Published: February 2014

Abstract. As the understanding and representation of the impacts of volcanic eruptions on climate have improved in the last decades, uncertainties in the stratospheric aerosol forcing from large eruptions are now linked not only to visible optical depth estimates on a global scale but also to details on the size, latitude and altitude distributions of the stratospheric aerosols. Based on our understanding of these uncertainties, we propose a new model-based approach to generating a volcanic forcing for general circulation model (GCM) and chemistry–climate model (CCM) simulations. This new volcanic forcing, covering the 1600–present period, uses an aerosol microphysical model to provide a realistic, physically consistent treatment of the stratospheric sulfate aerosols. Twenty-six eruptions were modeled individually using the latest available ice cores aerosol mass estimates and historical data on the latitude and date of eruptions. The evolution of aerosol spatial and size distribution after the sulfur dioxide discharge are hence characterized for each volcanic eruption. Large variations are seen in hemispheric partitioning and size distributions in relation to location/date of eruptions and injected SO2 masses. Results for recent eruptions show reasonable agreement with observations. By providing these new estimates of spatial distributions of shortwave and long-wave radiative perturbations, this volcanic forcing may help to better constrain the climate model responses to volcanic eruptions in the 1600–present period. The final data set consists of 3-D values (with constant longitude) of spectrally resolved extinction coefficients, single scattering albedos and asymmetry factors calculated for different wavelength bands upon request. Surface area densities for heterogeneous chemistry are also provided.
Removal of paraquat pesticide with Fenton reaction in a pilot scale water system
Authors: Oliveira C. , Gruskevica K. , Juhna T. , Tihomirova K. , Alves A. , Madeira L. M.
Published: February 2014

Abstract. Advanced oxidation processes, such as the Fenton's reagent, are powerful methods for decontamination of different environments from recalcitrant organics. In this work, the degradation of paraquat (PQ) pesticide was assessed (employing the commercial product gramoxone) directly inside the pipes of a pilot scale loop system; the effect of corroded cast iron pipe and loose deposits for catalysing the process was also evaluated. Results showed that complete degradation of paraquat ([PQ]0= 3.9 × 10−4 M, T = 20–30 °C, pH0 = 3, [H2O2]0 = 1.5 × 10−2 M and [Fe (II)] = 5.0 × 10−4 M,) was achieved within 8 h, either in lab scale or in the pilot loop. Complete PQ degradation was obtained at pH 3 whereas only 30% of PQ was degraded at pH 5 during 24 h. The installation of old cast iron segments with length from 0.5 to 14 m into PVC pipe loop system had a significant positive effect on degradation rate of PQ, even without addition of iron salt; the longer the iron pipes section, the faster was the pesticide degradation. Addition of loose deposits (mostly corrosion products composed of goethite, magnetite and a hydrated phase of FeO) also catalysed the Fenton reaction due to presence of iron in the deposits. Moreover, gradual addition of hydrogen peroxide improved gramoxone degradation and mineralization. This study showed for the first time that is possible to achieve complete degradation of pesticides in situ pipe water system and that deposits and corroded pipes catalyse oxidation of pesticides.
Simulating the connections of ENSO and the hydrology of the Blue Nile using a climate model of the tropics
Authors: Zaroug M. A. H. , Giorgi F. , Coppale E. , Eltahir E. A. B.
Published: February 2014

Abstract. We simulate the observed statistical relationship between ENSO and the hydrology of the Blue Nile using the tropical-band version of the regional climate model RegCM4 (or Reg-TB) for the 28 yr period 1982–2009. An ensemble of 9 simulations is completed to investigate the role of ENSO in the hydrology of the Blue Nile catchment. Re-TB shows a good skill in simulating the climatology of temperature, outgoing long-wave radiation patterns as well as related atmospheric circulation features during the summer season (i.e. the rainy season over the Blue Nile catchment). The model also succeeds in reproducing the observed negative correlation between Pacific SST and rainfall anomalies over the Blue Nile catchment, and in particular the association of droughts over the Blue Nile with El Niño events that start during the April–June period. We thus propose that observations as well as model forecasts of Pacific SST during this season should be used in seasonal forecasting of the Blue Nile flow.
A data-based comparison of flood frequency analysis methods used in France
Authors: Kochanek K. , Renard B. , Arnaud P. , Aubert Y. , Lang M. , Cipriani T. , Sauquet E.
Published: February 2014

Abstract. Flood frequency analysis (FFA) aims at estimating quantiles with large return periods for an extreme discharge variable. Many FFA implementations are used in operational practice in France. These implementations range from the estimation of a pre-specified distribution to continuous simulation approaches using a rainfall simulator coupled with a rainfall–runoff model. This diversity of approaches raises questions regarding the limits of each implementation and calls for a nation-wide comparison of their predictive performances. This paper presents the results of a national comparison of the main FFA implementations used in France. More accurately, eight implementations are considered, corresponding to the local, regional and local-regional estimation of Gumbel and Generalized Extreme Value (GEV) distributions, as well as the local and regional versions of a continuous simulation approach. A data-based comparison framework is applied to these eight competitors to evaluate their predictive performances in terms of reliability and stability, using daily flow data from more than 1000 gauging stations in France. Results from this comparative exercise suggest that two implementations dominate their competitors in terms of predictive performances, namely the local version of the continuous simulation approach and the local-regional estimation of a GEV distribution. More specific conclusions include the following: (i) the Gumbel distribution is not suitable for Mediterranean catchments, since this distribution demonstrably leads to an underestimation of flood quantiles; (ii) the local estimation of a GEV distribution is not recommended, because the difficulty in estimating the shape parameter results in frequent predictive failures; (iii) all the purely regional implementations evaluated in this study displayed a quite poor reliability, suggesting that prediction in completely ungauged catchments remains a challenge.
Heat loss from the Atlantic water layer in the St. Anna Trough (northern Kara Sea): causes and consequences
Authors: Dmitrenko I. A. , Kirillov S. A. , Serra N. , Koldunov N. V. , Ivanov V. V. , Schauer U. , Polyakov I. V. , Barber D. , Janout M. , Lien V. S. , Makhotin M. , Aksenov Y.
Published: February 2014

Abstract. A distinct, subsurface density front along the eastern St. Anna Trough in the northern Kara Sea is inferred from hydrographic observations in 1996 and 2008–2010. Direct velocity measurements show a persistent northward subsurface current (~ 20 cm s−1) along the St. Anna Trough eastern flank. This sheared flow, carrying the outflow from the Barents and Kara Seas to the Arctic Ocean, is also evident from shipboard observations as well as from geostrophic velocities and numerical model simulations. Although no clear evidence for the occurrence of shear instabilities could be obtained, we speculate that the enhanced vertical mixing along the St. Anna Trough eastern flank promoted by a vertical velocity shear favors the upward heat loss from the intermediate warm Atlantic water layer. The associated upward heat flux is inferred to 50–100 W m−2 using hydrographic data and model simulations. The zone of lowered sea ice thickness and concentration essentially marks the Atlantic water pathway in the St. Anna Trough and adjacent Nansen Basin continental margin from both sea-ice remote sensing observations and model simulations. In fact, the seaice shows a consistently delayed freeze-up onset during fall and a reduction in the seaice thickness during winter. This is consistent with our results on the enhanced Atlantic water heat loss along the Atlantic water pathway in the St. Anna Trough.1 1Dedicated to the memory of our colleague Klaus Hochheim who tragically lost his life in the Arctic expedition in September 2013
Solving Richards Equation for snow improves snowpack meltwater runoff estimations in detailed multi-layer snowpack model
Authors: Wever N. , Fierz C. , Mitterer C. , Hirashima H. , Lehning M.
Published: February 2014

Abstract. The runoff from a snow cover during spring snowmelt or rain-on-snow events is an important factor in the hydrological cycle. In this study, three water balance schemes for the 1 dimensional physically-based snowpack model SNOWPACK are compared to lysimeter measurements at two alpine sites with a seasonal snow cover, but with different climatological conditions: Weissfluhjoch (WFJ) and Col de Porte (CDP). The studied period consists of 14 and 17 yr, respectively. The schemes include a simple bucket-type approach, an approximation of Richards Equation (RE), and the full RE. The results show that daily sums of snowpack runoff are strongly related to a positive energy balance of the snow cover and therefore, all water balance schemes show very similar performance in terms of Nash-Sutcliffe efficiency (NSE) coefficients (around 0.63 and 0.72 for WFJ and CDP, respectively) and r2 values (around 0.83 and 0.72 for WFJ and CDP, respectively). An analysis of the runoff dynamics over the season showed that the bucket-type and approximated RE scheme release meltwater slower than in the measurements, whereas RE provides a better agreement. Overall, solving RE for the snow cover yields the best agreement between modelled and measured snowpack runoff, but differences between the schemes are small. On sub-daily time scales, the water balance schemes behave very differently. In that case, solving RE provides the highest agreement between modelled and measured snowpack runoff in terms of NSE coefficient (around 0.48 at both sites). At WFJ, the other water balance schemes loose most predictive power, whereas at CDP, the bucket-type scheme has an NSE coefficient of 0.39. The shallower and less stratified snowpack at CDP likely reduces the differences between the water balance schemes. Accordingly, it can be concluded that solving RE for the snow cover improves several aspects of modelling snow cover runoff, especially for deep, sub-freezing snow covers and in particular on the sub-daily time scales. The additional computational cost was found to be in the order of a factor of 1.5–2.
Atmosphere–ice forcing in the transpolar drift stream: results from the DAMOCLES ice-buoy campaigns 2007–2009
Authors: Haller M. , Brümmer B. , Müller G.
Published: February 2014

Abstract. During the EU research project Developing Arctic Modelling and Observing Capabilities for Long-term Environmental Studies (DAMOCLES), 18 ice buoys were deployed in the region of the Arctic transpolar drift (TPD). Sixteen of them formed a quadratic grid with 400 km side length. The measurements lasted from 2007 to 2009. The properties of the TPD and the impact of synoptic weather systems on the ice drift are analysed. Within the TPD, the speed increases by a factor of almost three from the North Pole to the Fram Strait region. The hourly buoy position fixes would show that the speed is underestimated by 10–20% if positions were taken at only 1–3 day intervals as it is usually done for satellite drift estimates. The geostrophic wind factor Ui / Ug (i.e. the ratio of ice speed Ui and geostrophic wind speed Ug), in the TPD amounts to 0.012 on average, but with regional and seasonal differences. The constant Ui / Ug relation breaks down for Ug < 5 m s−1. The impact of synoptic weather systems is studied applying a composite method. Cyclones (anticyclones) cause cyclonic (anticyclonic) vorticity and divergence (convergence) of the ice drift. The amplitudes are twice as large for cyclones as for anticyclones. The divergence caused by cyclones corresponds to a 0.1–0.5% per 6 h open water area increase based on the composite averages, but reached almost 4% within one day during a strong August 2007 storm. This storm also caused a long-lasting (over several weeks) rise of Ui and Ui / Ug and changed the ice conditions in a way which allowed large amplitudes of inertial ice motion. The consequences of an increasing Arctic storm activity for the ice cover are discussed.
Comunicación entre el IMLK - UPOLI y El Vaticano
Authors: Pérez Denis Alberto Torres
Published: February 2014

DOI: http://dx.doi.org/10.5377/cultura.v19i61.1291 Cultura de Paz Vol.19 No.61 2013; 4-5