bluuebunny/crossref_metadata_2025 huggingface dataset:
Stand Volume Estimation Using the k-NN Technique Combined with Forest Inventory Data, Satellite Image Data and Additional Feature Variables
Authors: Tanaka Shinya , Takahashi Tomoaki , Nishizono Tomohiro , Kitahara Fumiaki , Saito Hideki , Iehara Toshiro , Kodani Eiji , Awaya Yoshio
Published: December 2014

The main objective of this study was to evaluate the effectiveness of adding feature variables, such as forest type information and topographic- and climatic-environmental factors to satellite image data, on the accuracy of stand volume estimates made with the k-nearest neighbor (k-NN) technique in southwestern Japan. Data from the Forest Resources Monitoring Survey—a national plot sampling survey in Japan—was used as in situ data in this study. The estimates obtained from three Landsat Enhanced Thematic Mapper Plus (ETM+) datasets acquired in different seasons with various combinations of additional feature variables were compared. The results showed that although the addition of environmental factors to satellite image data did not always help improve estimation accuracy, the use of summer rainfall (SRF) data had a consistent positive effect on accuracy improvement. Therefore, SRF may be a useful feature variable to consider in stand volume estimation in this study area. Moreover, the use of forest type information is very effective at reducing k-NN estimation errors when using an optimum combination of satellite image data and environmental factors. All of the results indicated that the k-NN technique combined with appropriate feature variables is applicable to nationwide stand volume estimation in Japan.
Radiometric Non-Uniformity Characterization and Correction of Landsat 8 OLI Using Earth Imagery-Based Techniques
Authors: Pesta Frank , Bhatta Suman , Helder Dennis , Mishra Nischal
Published: December 2014

Landsat 8 is the first satellite in the Landsat mission to acquire spectral imagery of the Earth using pushbroom sensor instruments. As a result, there are almost 70,000 unique detectors on the Operational Land Imager (OLI) alone to monitor. Due to minute variations in manufacturing and temporal degradation, every detector will exhibit a different behavior when exposed to uniform radiance, causing a noticeable striping artifact in collected imagery. Solar collects using the OLI’s on-board solar diffuser panels are the primary method of characterizing detector level non-uniformity. This paper reports on an approach for using a side-slither maneuver to estimate relative detector gains within each individual focal plane module (FPM) in the OLI. A method to characterize cirrus band detector-level non-uniformity using deep convective clouds (DCCs) is also presented. These approaches are discussed, and then, correction results are compared with the diffuser-based method. Detector relative gain stability is assessed using the side-slither technique. Side-slither relative gains were found to correct streaking in test imagery with quality comparable to diffuser-based gains (within 0.005% for VNIR/PAN; 0.01% for SWIR) and identified a 0.5% temporal drift over a year. The DCC technique provided relative gains that visually decreased striping over the operational calibration in many images.
On Uncertainties of the Priestley-Taylor/LST-Fc Feature Space Method to Estimate Evapotranspiration: Case Study in an Arid/Semiarid Region in Northwest China
Authors: Li Zhansheng , Jia Li , Lu Jing
Published: December 2014

Accurate evapotranspiration (ET) estimation is very crucial for water resource management, particularly for the arid and semi-arid region. The remote sensing-based Priestley-Taylor method (RS-PT method) can estimate ET at regional scale, using the feature space of remotely sensed land surface temperature (LST) and vegetation index (VI). This study evaluates the RS-PT feature space method over an arid and semi-arid region in northwest China using satellite data from the moderate-resolution space-borne sensor Advanced Along-Track Scanning Radiometer (AATSR), the observations from the high-resolution airborne sensor Wide-angle Infrared Dual-mode line/area Array Scanner (WiDAS) and ground measurements of heat fluxes collected in summer 2008. The results show that the mean difference for latent heat flux (LE) estimates resulting from different domain sizes is 69.5 W/m2. When using high-resolution images from airborne measurements, the dry boundary is strongly affected by the pixels of impervious surfaces, which lead to a mean difference of 15.36 W/m2 for LE estimates. In addition, the physically based Surface Energy Balance Index (SEBI) model is used to analyze the accuracy of dry/wet boundaries in the RS-PT method. Compared with the SEBI-estimated relative evaporative fraction (Λr), the RS-PT method underestimated Λr by ~0.11. For the RS-PT method, the uncertainty in the determination of the dry/wet boundaries has a significant impact on the accuracy of the ET estimate, not only depending on the size of the area to build the feature space, but also on the land covers.
Rapid Elemental Analysis and Provenance Study of Blumea balsamifera DC Using Laser-Induced Breakdown Spectroscopy
Authors: Liu Xiaona , Zhang Qiao , Wu Zhisheng , Shi Xinyuan , Zhao Na , Qiao Yanjiang
Published: December 2014

Laser-induced breakdown spectroscopy (LIBS) was applied to perform a rapid elemental analysis and provenance study of Blumea balsamifera DC. Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were implemented to exploit the multivariate nature of the LIBS data. Scores and loadings of computed principal components visually illustrated the differing spectral data. The PLS-DA algorithm showed good classification performance. The PLS-DA model using complete spectra as input variables had similar discrimination performance to using selected spectral lines as input variables. The down-selection of spectral lines was specifically focused on the major elements of B. balsamifera samples. Results indicated that LIBS could be used to rapidly analyze elements and to perform provenance study of B. balsamifera.
Pseudo Optimization of E-Nose Data Using Region Selection with Feature Feedback Based on Regularized Linear Discriminant Analysis
Authors: Jeong Gu-Min , Nghia Nguyen , Choi Sang-Il
Published: December 2014

In this paper, we present a pseudo optimization method for electronic nose (e-nose) data using region selection with feature feedback based on regularized linear discriminant analysis (R-LDA) to enhance the performance and cost functions of an e-nose system. To implement cost- and performance-effective e-nose systems, the number of channels, sampling time and sensing time of the e-nose must be considered. We propose a method to select both important channels and an important time-horizon by analyzing e-nose sensor data. By extending previous feature feedback results, we obtain a two-dimensional discriminant information map consisting of channels and time units by reverse mapping the feature space to the data space based on R-LDA. The discriminant information map enables optimal channels and time units to be heuristically selected to improve the performance and cost functions. The efficacy of the proposed method is demonstrated experimentally for different volatile organic compounds. In particular, our method is both cost and performance effective for the real implementation of e-nose systems.
Land Use/Land Cover Change Induced Impacts on Water Supply Service in the Upper Reach of Heihe River Basin
Authors: Geng Xiaoli , Wang Xinsheng , Yan Haiming , Zhang Qian , Jin Gui
Published: December 2014

Heihe River Basin is the second largest inland river basin in China, where water supply service in the upper reach has greater influence on the sustainable development of middle and lower reaches. This study analyzed the influence of land use/land cover change (LUCC) on the water supply service in the upper reach by carrying out scenario simulation. Firstly, we analyzed the LUCC and climate change in the upper reach during 1990–2005; then the water supply service, which was represented by the annual water yield, was estimated with the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model. Thereafter three scenarios (precipitation change and LUCC change combined, LUCC change only, and precipitation change only) were established to analyze the impacts of LUCC and precipitation change on the water yield. The results show that the LUCC exerted great influence on water yield, while the impact of precipitation change is even more significant than that of LUCC. Although there are still some uncertainties, the results of this study can still provide valuable reference information for ecological conservation and water resource management in the upper reach of the Heihe River Basin.
Maize Production Responsiveness to Land Use Change and Climate Trends in Cameroon
Authors: Epule Terence , Bryant Christopher
Published: December 2014

Most studies on the responsiveness of maize production to various variables have dwelled on the responsiveness of maize production to variations in precipitation or temperature. This study seeks to verify the response of maize production in Cameroon to both climate trends and land use change. Therefore, for the first time, our study presents findings on the relative influence of both climate and land use change on maize production in Cameroon. The data used in this analysis are essentially time series data spanning the period 1961–2006. The data on quantity of maize produced, area of maize harvested and number of maize seeds planted was taken from (http://faostat.fao.org). The mean maize growing season temperature and precipitation data were collected from the 0.5° × 0.5° gridded collaborative datasets of the UNEP and the School of Geography and Environment at Oxford University and from the global crop calendar dataset. The data were analyzed using the average rate of change, detrended simulations, the multiple linear regression technique, correlation coefficient and the coefficient of determination. The results show that maize production in Cameroon is more likely responsive to land use change (forest area change) than rainfall and temperature. However, for the climatic variables, maize production is more responsive to temperature variations than precipitation. In other words, the greater the land use change (forest area loss) the more likely the long run losses in the current maize production gains while rising temperatures were found to be more suitable for maize production. Even though the 1990s marked the period of recovering rainfall levels in most of the Sahel, large fluctuations were still recorded.
On the female of Gypona reversa DeLong & Martinson, 1972, with emphasis on genital structures (Insecta: Hemiptera: Cicadellidae)
Authors: Da-Silva Elidiomar , Coelho Luci , Ferreira Paulo Sérgio
Published: December 2014

Gypona reversa DeLong & Martinson, 1972 has its ovipositor described and illustrated based on the examination of specimens from its type locality. This is the first species of Gypona Germar, 1821 to have the female genitalia detailed description published.
La désarticulation de la politique RSE des entreprises : Une étude exploratoire
Authors: Bruna Maria Giuseppina , Dang Rey , Vo Linh Chi
Published: December 2014

A la croisée du management stratégique, de la GRH et de la sociologie des organisations, cette recherche exploratoire questionne le lien entre le niveau de maturité de la politique RSE d’une entreprise et le degré de féminisation de son Conseil d’administration (ou de surveillance). La proportion d’administratrices constitue-t-elle un indicateur de la maturité et de l’effectivité d’une politique de RSE ou reflète-t-elle, a minima, le niveau de conscientisation sociétale d’une organisation ? D’un point de vue méthodologique, la recherche s’appuie sur une analyse de contenu de la divulgation sociétale de six entreprises appartenant à l’indice CAC 40 relative à l’exercice 2009, qu’elle éclaire à l’aune des théories des ressources, néo-institutionnaliste et de la légitimité. Le niveau de maturité d’une politique RSE est évalué selon trois dimensions structurantes : « gouvernance et stratégie de groupe » ; « engagement écologique et implication dans le développement durable », et « management responsable des ressources humaines et promotion de la diversité ». Malgré des nuances notables d’une firme à l’autre, l’étude révèle le caractère faiblement stratégique des politiques RSE déployées par les entreprises étudiées, à la fin de la première décade du XXI e siècle. Elle dévoile la fragilité de ces démarches, leur caractère souvent haché, peu transversal et faiblement intégré, ce qui tend à réduire leur impact systémique. L’absence d’une relation significative entre le niveau de conscience sociale et sociétale d’une organisation et le degré de féminisation de son Conseil d’Administration se fait signe d’une insuffisante structuration des CSR policies . C’est pourquoi l’article plaide en faveur de démarches de RSE stratégiques, systémiques, transversales, partenariales et durables, sises sur une réelle dynamique transformative.
Exploration des conversations du changement à destination des parties prenantes externes à travers la rhétorique du leadership
Authors: Montargot Nathalie , Ben Lahouel Béchir
Published: December 2014

De quelle manière les leaders communiquent avec leurs parties prenantes externes en période de changement organisationnel ? L’objectif de cette recherche exploratoire est de présenter empiriquement une approche linguistique pour une meilleure compréhension de la nature de la communication du changement. Le modèle des conversations du changement (Ford et Ford, 1995) et la théorie des actes de langage (Searle, 1979) servent de trame au développement des questions de recherche et permettent la discussion des résultats issus de l’analyse textuelle. Les discours de 29 leaders d’entreprises françaises, entre 2007 et 2012, ont été analysés. Les résultats montrent que la rhétorique est fondée essentiellement sur les conversations d’initiative, afin de convaincre de la pertinence et du bien-fondé des motifs de changement. Il apparaît que la rhétorique du changement est construite autour d’une argumentation logique de persuasion, composée d’actes de langage de types assertifs, promissifs et expressifs. Nous insistons sur l’importance du management actif du langage par les leaders dans un contexte de changement.
Réflexions sur l'innovation organisationnelle à l'ère du numérique
Authors: Marchal Aurélie
Published: December 2014

L’impact de la révolution digitale est magistral. D’après Michel Serres, il ne s’agit pas moins de la troisième révolution de l’Humanité après celle du passage du stade oral au stade écrit, puis celle du stade écrit au stade imprimé. Les outils numériques modifient radicalement notre relation à l’espace, au temps et aux autres. Il y aurait par ailleurs énormément à dire sur les transformations relationnelles provoquées par la révolution numérique. Le développement de l’accès à l’information et des réseaux sociaux renforce l’affaiblissement déjà amorcé de tout système hiérarchique. Dans ce contexte on ne peut plus déstabilisant, comment les acteurs de la conduite du changement doivent-ils se positionner, pris en étaux entre la direction stratégique qui, par nature, décide, et les acteurs du terrain qui revendiquent d’être davantage impliqués dans la conduite du changement ? L’article propose la description et l’analyse d’une nouvelle approche de conduite du changement : le design thinking, processus utilisé par les designers pour innover de manière extrêmement pertinente à partir des usages, qu’ils soient déjà existants ou encore à inventer.
La conduite du changement digital au défi de l'acceptabilité et de la sécurité
Authors: Rigaud Eric , Côte Thomas , Vatin Gabriel , Napoli Aldo
Published: December 2014

La finalité de cette communication est d’identifier un ensemble de facteurs pouvant causer l’échec de l’adoption d’une technologie innovante et la survenue d’une situation non souhaitée telle qu’un incident, un accident ou bien une crise. Les facteurs sont illustrés avec le contexte de l’information géographique et une série de questions est proposée afin de soutenir l’anticipation de situations non souhaitées lors de la conduite d’un projet d’innovation.
Les pharmaciens et la médiatisation de la spécialité au xix e siècle
Authors: Sueur Nicolas
Published: December 2014

Perçue comme particulièrement dégradante par les pharmaciens au début du siècle, la publicité ne cesse de progresser jusqu’à envahir la presse grand public à la veille de la guerre. Elle est surtout utilisée pour une gamme de produits que l’on appelle les spécialités. Elle prend des formes multiples (affiche, catalogue, notice, note scientifique), se diversifie, et accompagne le mouvement de médicamentalisation de la société. Médiatisées, les spécialités gagnent en légitimité et envahissent les officines.
Médecins et malades dans la caricature (1830-1944)
Authors: Duccini Hélène , Duetto Article
Published: December 2014

Comment les caricaturistes se sont-ils saisis de la représentation des médecins et des malades entre 1830 et 1944 ? Durant cette période, leurs représentations accompagnent la transformation de la médecine, cet art devenu science. Plusieurs conclusions émergent du travail. Le malade est très présent dans les caricatures qui se gaussent largement de lui avec des représentations fortement stéréotypées. La dérision des malades imaginaires se retrouve pendant toute la période. La satire des médecins est tout aussi stéréotypée et plus cruelle : la moquerie accable de préférence le médecin, l’autorité sans partage des professeurs de médecine, l’inefficacité de leur prise en charge ou de leurs traitements.
La santé publique à partir de l'image : la consommation de cannabis au prisme du cinéma depuis la fin des années 1960
Authors: Pointeau-Lagadec Erwan , Duetto Article
Published: December 2014

Les consommations de drogue constituent un enjeu de santé publique de premier ordre dans la majorité des pays occidentaux, et notamment en France. En s’appuyant sur l’exemple de l’étude historique des représentations du cannabis dans les films français depuis la fin des années 1960, l’article veut mettre en évidence la possibilité pour les chercheurs en sciences humaines d’envisager la question des produits psychotropes illicites et de leurs usages au travers des productions audiovisuelles et médiatiques.
mHealth : l'information de santé ubique ?
Authors: Al Dahdah Marine
Published: December 2014

Avec près de sept milliards d’usagers « mobile » en 2014, le téléphone portable devient la technologie d’information et de communication la plus utilisée dans le monde. Du « dossier patient » mobile à l’envoi dématérialisé de données cliniques par SMS, ces dispositifs se développent de manière croissante dans un contexte de réduction des ressources et des dépenses de santé, mais aussi d’implication croissante des patients. Si l’information de santé sur internet a donné lieu à de nombreux travaux, l’utilisation du téléphone portable, appelée «  mHealth  » ou « mSanté », reste un champ à défricher.
Une presse influenzée ? Le traitement journalistique de la pandémie de grippe « russe » à Paris (1889-1890)
Authors: Vagneron Frédéric
Published: December 2014

Restée dans l’ombre de la grippe « espagnole », l’épidémie de grippe « russe » de l’hiver 1889-1890 n’a connu qu’un faible intérêt historiographique. Elle fournit pourtant un cas inédit pour observer le rôle déterminant joué par la presse durant une crise sanitaire internationale. En effet, la pandémie grippale de 1889-1890 constitue la première épidémie de l’ère de la presse d’information, au seuil d’une période où la science bactériologique déploie une nouvelle interprétation des maladies et de leur circulation. A partir d’un corpus de quatre journaux ( Le Matin ; Le Temps ; Le Petit Journal ; La Presse ), l’article étudie le rôle de la presse comme agent et protagoniste de la mobilisation face à l’épidémie lors de son apparition à Paris, à l’interface entre populations et autorités politiques et sanitaires. En confrontant les savoirs disponibles à ses informations de terrain ou télégraphiques, en plaçant l’enquête au plus près d’une population qui constitue son lectorat, en dénonçant les mesures des autorités ou en les relayant, les différents titres participent activement à l’avènement de l’événement et à sa politisation dans la capitale. Ce n’est que plus tard que la statistique fait apparaître l’ampleur de la mortalité à l’échelle nationale.
« Partager ma propre opinion ». La grippe H1N1 : connaissances et échanges électroniques
Authors: Méadel Cécile
Published: December 2014

Dans les domaines de la santé où la connaissance était jusqu’au début des années 1990 très spécialisée et réservée à des sphères professionnelles fermées, l’internet a accompagné et favorisé une transformation radicale de la circulation des savoirs ; les patients ont désormais à leur disposition une masse considérable d’informations. Cette ouverture vient mettre au défi les anciens partages entre savant et profane, entre connaissance validée et opinion informée. L’échec au moins relatif de la campagne de vaccination contre la grippe H1N1 en 2009 permet de s’interroger sur la circulation des connaissances et sur les trajectoires informatives des patients-citoyens.
S'informer via des médias sociaux de santé : quelle place pour les experts ?
Authors: Paganelli Céline , Clavier Viviane , Duetto Article
Published: December 2014

Les médias sociaux de santé permettent aux internautes de s’informer, de partager leurs expériences et représentent un espace qui s’affranchit de la sphère spécialisée, incarnée par les professionnels de santé. Pourtant, on constate que ces médias s’organisent autour de figures d’experts, qu’elles soient fondées sur le parcours de vie des internautes ou sur les experts traditionnels. L’analyse d’un corpus de messages issus de médias sociaux et portant sur des maladies graves ou orphelines montre que près de la moitié des messages postés font référence aux professionnels de santé.
Le rôle d'Internet dans la construction des risques relatifs à la consommation détournée de médicaments par des jeunes adultes québécois
Authors: Thoër Christine , Robitaille Michelle , Duetto Article
Published: December 2014

L’utilisation des médicaments à des fins détournées semble de plus en plus populaire auprès des jeunes adultes. Cette recherche qui s’appuie sur des entretiens semi-dirigés réalisés avec quarante-six Québécois âgés de 18 à 25 ans qui utilisent les médicaments à des fins de recherche de sensations et d’amélioration de la performance, vise à cerner leurs usages d’Internet pour s’informer sur ces pratiques. Usages et modalités d’appropriation de l’information varient selon les individus qui mobilisent différentes ressources, en ligne et hors ligne, mais consultent peu les professionnels de la santé.
HRCT Correlation with Round Window Identification during Cochlear Implantation in Children
Authors: Pendem Sai Kiran , Rangasami Rajeswaran , Arunachalam Ravi Kumar , Mohanarangam Venkata Sai Pulivadulu , Natarajan Paarthipan
Published: December 2014

Objective:

To determine the accuracy of High Resolution Computer Tomography (HRCT) temporal bone measurements in predicting the actual visualization of round window niche as viewed through posterior tympanotomy (i.e. facial recess).

Materials and Methods:

This is a prospective study of 37 cochlear implant candidates, aged between 1and 6 years, who were referred for HRCT temporal bone during the period December 2013 to July 2014. Cochlear implantation was done in 37 children (25 in the right ear and 12 in the left ear). The distance between the short process of incus and the round window niche and the distance between the oval window and the round window niche were measured preoperatively on sub-millimeter (0.7 mm) HRCT images. We classified the visibility of round window niche based on the surgical view (i.e. through posterior tympanotomy) during surgery into three types: 1) Type 1- fully visible, 2) Type 2- partially visible, and 3) Type 3- difficult to visualize. The preoperative HRCT measurements were used to predict the type of visualization of round window niche before surgery and correlated with the findings during surgery.

Results:

The mean and standard deviation for the distance between the short process of incus and the round window niche and for the distance between the oval window and the round window niche for Types 1, 2, and 3 were 8.5 ± 0.2 mm and 3.2 ± 0.2 mm, 8.0 ± 0.4 mm and 3.8 ± 0.2 mm, 7.5 ± 0.2 mm and 4.4 ± 0.2 mm respectively, and showed statistically significant difference (P < 0.01) between them. The preoperative HRCT measurements had a sensitivity and specificity of 92.3% and 96.2%, respectively, in determining the actual visualization of round window niche.

Conclusion:

This study shows preoperative HRCT temporal bone measurements are useful in predicting the actual visualization of round window niche as viewed through posterior tympanotomy.
MRI of Uncommon Lesions of the Large Bowel: A Pictorial Essay
Authors: Lee Christine U , Glockner James F
Published: December 2014

This pictorial essay briefly discusses methods for optimizing bowel imaging with magnetic resonance imaging (MRI) and illustrates the MRI appearance of a variety of unusual lesions involving or related specifically to the large bowel.
Superior Mesenteric Artery-Related Aortic Pseudomass as a Form of Reverberation Artifact in a 10-Year-Old Boy
Authors: Kokhanovsky Natalia , Nachtigal Alicia , Reindorp Nadir , Zeina Abdel-Rauf
Published: December 2014

Artifacts are encountered routinely in clinical ultrasonography practice. The ability to recognize and eliminate potentially correctable ultrasound artifacts is of great importance to image quality improvement and optimal patient care. We describe an example of a superior mesenteric artery-related pseudomass as a form of reverberation artifact that could lead to misinterpretation of sonographic findings. We present the ultrasonographic and computed tomography angiography findings and give an explanation for the appearance of the artifact.
La construcción de la estrategia comunicativa en Twitter de un falso documental: Operación Palace
Authors: Quintas Froufe Natalia , González Neira Ana , Díaz-González María Jesús
Published: December 2014

Este artículo analiza la estrategia llevada a cabo en Twitter para la promoción de la emisión del polémico programa El especial 23F: Operación Palace durante el prime time del 23 de febrero de 2014 en La Sexta. Metodología: Se registró la actividad de las seis cuentas emisoras haciendo un seguimiento del flujo de todos los tuits durante la semana previa y posterior a la emisión. Resultados. La actividad de sus cuentas ha sido muy desigual, destacando a Évole y la cuenta oficial del programa como las más activas. Discusión y conclusiones: Aunque Twitter permite establecer un diálogo entre el público y el programa, del análisis realizado se concluye que la mayor parte de las cuentas no entablan ese contacto con sus seguidores en esta red, excepto Évole. Asimismo, desde esas cuentas se favoreció la confusión de la audiencia durante la promoción del falso documental.
Oxygenic photosynthesis: translation to solar fuel technologies
Authors: Janna Olmos Julian David , Kargul Joanna
Published: December 2014

Mitigation of man-made climate change, rapid depletion of readily available fossil fuel reserves and facing the growing energy demand that faces mankind in the near future drive the rapid development of economically viable, renewable energy production technologies. It is very likely that greenhouse gas emissions will lead to the significant climate change over the next fifty years. World energy consumption has doubled over the last twenty-five years, and is expected to double again in the next quarter of the 21st century. Our biosphere is at the verge of a severe energy crisis that can no longer be overlooked. Solar radiation represents the most abundant source of clean, renewable energy that is readily available for conversion to solar fuels. Developing clean technologies that utilize practically inexhaustible solar energy that reaches our planet and convert it into the high energy density solar fuels provides an attractive solution to resolving the global energy crisis that mankind faces in the not too distant future. Nature’s oxygenic photosynthesis is the most fundamental process that has sustained life on Earth for more than 3.5 billion years through conversion of solar energy into energy of chemical bonds captured in biomass, food and fossil fuels. It is this process that has led to evolution of various forms of life as we know them today. Recent advances in imitating the natural process of photosynthesis by developing biohybrid and synthetic “artificial leaves” capable of solar energy conversion into clean fuels and other high value products, as well as advances in the mechanistic and structural aspects of the natural solar energy converters, photosystem I and photosystem II, allow to address the main challenges: how to maximize solar-to-fuel conversion efficiency, and most importantly: how to store the energy efficiently and use it without significant losses. Last but not least, the question of how to make the process of solar energy conversion into fuel not only efficient but also cost effective, therefore attractive to the consumer, should be properly addressed.
The evolution of land plants: a perspective from horizontal gene transfer
Authors: Wang Qia , Sun Hang , Huang Jinling
Published: December 2014

Recent studies suggest that horizontal gene transfer (HGT) played a significant role in the evolution of eukaryotic lineages. We here review the mechanisms of HGT in plants and the importance of HGT in land plant evolution. In particular, we discuss the role of HGT in plant colonization of land, phototropic response, C4 photosynthesis, and mitochondrial genome evolution.
Plastid origin: who, when and why?
Authors: Ku Chuan , Roettger Mayo , Zimorski Verena , Nelson-Sathi Shijulal , Sousa Filipa L. , Martin William F.
Published: December 2014

The origin of plastids is best explained by endosymbiotic theory, which dates back to the early 1900s. Three lines of evidence based on protein import machineries and molecular phylogenies of eukaryote (host) and cyanobacterial (endosymbiont) genes point to a single origin of primary plastids, a unique and important event that successfully transferred two photosystems and oxygenic photosynthesis from prokaryotes to eukaryotes. The nature of the cyanobacterial lineage from which plastids originated has been a topic of investigation. Recent studies have focused on the branching position of the plastid lineage in the phylogeny based on cyanobacterial core genes, that is, genes shared by all cyanobacteria and plastids. These studies have delivered conflicting results, however. In addition, the core genes represent only a very small portion of cyanobacterial genomes and may not be a good proxy for the rest of the ancestral plastid genome. Information in plant nuclear genomes, where most genes that entered the eukaryotic lineage through acquisition from the plastid ancestor reside, suggests that heterocyst-forming cyanobacteria in Stanier’s sections IV and V are most similar to the plastid ancestor in terms of gene complement and sequence conservation, which is in agreement with models suggesting an important role of nitrogen fixation in symbioses involving cyanobacteria. Plastid origin is an ancient event that involved a prokaryotic symbiont and a eukaryotic host, organisms with different histories and genome evolutionary processes. The different modes of genome evolution in prokaryotes and eukaryotes bear upon our interpretations of plastid phylogeny.
Unique genome evolution in an intracellular N2-fixing symbiont of a rhopalodiacean diatom
Authors: Nakayama Takuro , Inagaki Yuji
Published: December 2014

Cyanobacteria, the major photosynthetic prokaryotic lineage, are also known as a major nitrogen fixer in nature. N2-fixing cyanobacteria are frequently found in symbioses with various types of eukaryotes and supply fixed nitrogen compounds to their eukaryotic hosts, which congenitally lack N2-fixing abilities. Diatom species belonging to the family Rhopalodiaceae also possess cyanobacterial symbionts called spheroid bodies. Unlike other cyanobacterial N2-fixing symbionts, the spheroid bodies reside in the cytoplasm of the diatoms and are inseparable from their hosts. Recently, the first spheroid body genome from a rhopalodiacean diatom has been completely sequenced. Overall features of the genome sequence showed significant reductive genome evolution resulting in a diminution of metabolic capacity. Notably, despite its cyanobacterial origin, the spheroid body was shown to be truly incapable of photosynthesis implying that the symbiont energetically depends on the host diatom. The comparative genome analysis between the spheroid body and another N2-fixing symbiotic cyanobacterial group corresponding to the UCYN-A phylotypes – both were derived from cyanobacteria closely related to genus Cyanothece – revealed that the two symbionts are on similar, but explicitly distinct tracks of reductive evolution. Intimate symbiotic relationships linked by nitrogen fixation as seen in rhopalodiacean diatoms may help us better understand the evolution and mechanisms of bacterium-eukaryote endosymbioses.
Primary endosymbiosis: have cyanobacteria and Chlamydiae ever been roommates?
Authors: Deschamps Philippe
Published: December 2014

Eukaryotes acquired the ability to process photosynthesis by engulfing a cyanobacterium and transforming it into a genuine organelle called the plastid. This event, named primary endosymbiosis, occurred once more than a billion years ago, and allowed the emergence of the Archaeplastida, a monophyletic supergroup comprising the green algae and plants, the red algae and the glaucophytes. Of the other known cases of symbiosis between cyanobacteria and eukaryotes, none has achieved a comparable level of cell integration nor reached the same evolutionary and ecological success than primary endosymbiosis did. Reasons for this unique accomplishment are still unknown and difficult to comprehend. The exploration of plant genomes has revealed a considerable amount of genes closely related to homologs of Chlamydiae bacteria, and probably acquired by horizontal gene transfer. Several studies have proposed that these transferred genes, which are mostly involved in the functioning of the plastid, may have helped the settlement of primary endosymbiosis. Some of these studies propose that Chlamydiae and cyanobacterial symbionts coexisted in the eukaryotic host of the primary endosymbiosis, and that Chlamydiae provided solutions for the metabolic symbiosis between the cyanobacterium and the host, ensuring the success of primary endosymbiosis. In this review, I present a reevaluation of the contribution of Chlamydiae genes to the genome of Archaeplastida and discuss the strengths and weaknesses of this tripartite model for primary endosymbiosis.
Paulinella chromatophora – rethinking the transition from endosymbiont to organelle
Authors: Nowack Eva C.M.
Published: December 2014

Eukaryotes co-opted photosynthetic carbon fixation from prokaryotes by engulfing a cyanobacterium and stably integrating it as a photosynthetic organelle (plastid) in a process known as primary endosymbiosis. The sheer complexity of interactions between a plastid and the surrounding cell that started to evolve over 1 billion years ago, make it challenging to reconstruct intermediate steps in organelle evolution by studying extant plastids. Recently, the photosynthetic amoeba Paulinella chromatophora was identified as a much sought-after intermediate stage in the evolution of a photosynthetic organelle. This article reviews the current knowledge on this unique organism. In particular it describes how the interplay of reductive genome evolution, gene transfers, and trafficking of host-encoded proteins into the cyanobacterial endosymbiont contributed to transform the symbiont into a nascent photosynthetic organelle. Together with recent results from various other endosymbiotic associations a picture emerges that lets the targeting of host-encoded proteins into bacterial endosymbionts appear as an early step in the establishment of an endosymbiotic relationship that enables the host to gain control over the endosymbiont.
Stromuling when stressed!
Authors: Krenz Björn , Guo Tai Wei , Kleinow Tatjana
Published: December 2014

Stromules are stroma-filled tubules, extruding from the plastid and surrounded by both envelope membranes, but so far, stromules remain enigmatic structures and their function unknown. Stromules can interconnect plastids and have been found to associate with the nucleus, endoplasmic reticulum, Golgi complex, plasma membrane, mitochondria and peroxisomes. This minireview briefly summarizes markers to visualize stromules, inducers of stromules and provides new data about plant virus induced stromules.
O labirinto textual de O ano da morte de Ricardo Reis, de José Saramago
Authors: Oliveira Juliana Prestes de , Oliveira Raquel Trentin de
Published: December 2014

No romance O ano da morte de Ricardo Reis (1984), do escritor José Saramago, que pode ser lido sob o viés do Pós-Modernismo, o autor constrói uma narrativa repleta de intertextos, em que a história das personagens dialoga com a história de Portugal em 1936, época na qual o país sofria a ditadura de Salazar. Buscamos explorar essa construção, investigando como ocorre a elaboração da narrativa e sua constituição histórico-literária. Ademais, refletimos sobre os limites entre ficção e(H)história, investigando como o romance contribui para a desestabilização dos discursos tidos como verdadeiros. Uma das estratégias do autor para problematizar a questão da veracidade da visão historiográfica tradicional é a utilização de diversas vozes, especialmente daquelas silenciadas pelo poder, o que sugere que um mesmo acontecimento pode ter várias versões. Refletindo crítica e reflexivamente sobre o passado, a ficção reconfigura a imagem dos acontecimentos históricos, apresentando-nos outra face da (H)história do país.
Entrevista com Flávio Tavares
Authors: Birman Daniela
Published: December 2014

Entrevista com o jornalista e escritor Flávio Tavares sobre o seu livro Memórias do esquecimento (1999)
VARIAÇÃO BIOMÉTRICA DE DIÁSPOROS DE BURITI (Mauritia flexuosa L.f. – ARECACEAE) EM VEREDAS EM DIFERENTES ESTÁGIOS DE CONSERVAÇÃO
Authors: Matos Fabiano dos Santos , Nunes Yule Roberta Ferreira , Silva Márcia Aparecida Pereira , Oliveira Islaine de Sena
Published: December 2014

http://dx.doi.org/10.5902/1980509816583As veredas são fitofisionomias do bioma Cerrado, onde, no estrato arbóreo, predomina a palmeira arbórea Mauritia flexuosa L.f. - buriti, espécie considerada recurso-chave para muitos animais, que a utilizam como moradia e fonte alimentar, e também pelo próprio homem, que usa suas folhas e frutos como matéria-prima e alimento. Apesar de ocorrerem em ambientes protegidos pela legislação ambiental, ações antrópicas nas veredas têm afetado as populações do buriti, por meio da diminuição do número de indivíduos ocasionada por desmatamento, assoreamento e drenagem dessas áreas. O objetivo desse trabalho foi avaliar a morfometria de frutos e sementes de buriti oriundos de seis veredas em diferentes estágios de conservação, situadas na Área de Proteção Ambiental do Rio Pandeiros (norte de Minas Gerais). Foram amostrados, no total, 1800 frutos e sementes, que foram mensurados em comprimento, largura, espessura e peso. Para detectar diferenças das medidas morfométricas dos frutos e das sementes entre as áreas de coleta foi feita a análise de variância. Foram observadas variações nas medidas morfométricas de frutos e sementes entre as áreas de estudo, sendo que 87,5% das maiores médias ocorreram em áreas com menores intervenções antrópicas. Esse fato, possivelmente, está relacionado aos impactos ocorridos nas veredas, além das variações genéticas que podem incidir sobre os indivíduos.
ESTOQUES DE CARBONO E NITROGÊNIO EM ARGISSOLO SUBMETIDO AO MONOCULTIVO DE Eucalyptus urograndis E EM ROTAÇÃO COM Acacia mangium
Authors: Pegoraro Rodiney Facco , Silva Ivo Ribeiro da , Novais Roberto Ferreira de , Barros Nairam Felix de , Cantatutti Reinaldo Bertola , Fonseca Sebastião
Published: December 2014

http://dx.doi.org/10.5902/1980509816607A busca de sistemas sustentáveis de manejo do solo tem levado pesquisadores a desenvolverem novas técnicas de cultivo. Dentre elas, destacam-se no Brasil estudos realizados com espécies florestais capazes de fixar N2 atmosférico e aumentar o estoque de C e N em frações lábeis e estáveis da matéria orgânica do solo (MOS). O presente estudo teve por objetivo avaliar as alterações nos estoques de C e N em frações das substâncias húmicas, da fração leve da MOS e da matéria microbiana em solos cultivados com Eucalyptus urograndis em rotação curta, eucalipto em rotação longa e povoamentos de Acacia mangium que sucederam plantios de eucalipto em rotação curta, tendo como referência o solo de floresta nativa (Mata Atlântica) adjacente. Foram quantificados os estoques de C orgânico total e N total (COT e NT), nas frações das substâncias húmicas (fração ácido fúlvico-AF, fração ácido húmico-AH e fração humina-H), C e N da fração leve da MOS (C-MOL e N-MOL) e estoque de C e N da matéria microbiana (C-BM e N-BM). Os resultados indicaram que o cultivo do eucalipto em rotação curta apresentou menores estoques de COT e NT, nas frações das substâncias húmicas e, de N na matéria microbiana em comparação ao solo sob rotação com Acacia mangium. O cultivo de Acacia mangium e o aumento do tempo da rotação do eucalipto incrementaram os estoques de C e N da maioria das frações lábeis (C-MOL, N-MOL e C-BM) e estáveis (C e N nas substâncias húmicas). Indicando tendência de recuperação dos seus estoques para valores próximos daqueles originais (mata nativa), sendo superiores aos estoques obtidos na área de eucalipto em rotação curta.
QUINTAIS AGROFLORESTAIS: ESTRUTURA, COMPOSIÇÃO FLORÍSTICA E ASPECTOS SOCIOAMBIENTAIS EM ÁREA DE ASSENTAMENTO RURAL NA AMAZÔNIA BRASILEIRA
Authors: Almeida Larissa Santos de , Gama João Ricardo Vasconcellos
Published: December 2014

http://dx.doi.org/10.5902/1980509816617O levantamento da estrutura, composição florística e aspectos socioambientais dos quintais agroflorestais foi realizado na comunidade Santo Antônio, município de Santarém, Pará, Brasil. O local de estudo compreende 6 QAFs, onde também foram ouvidos os manejadores de cada quintal e mais 2 moradores antigos. Foi amostrado um total de 522 indivíduos compreendendo 90 espécies e 53 famílias botânicas. A família que apresentou maior número de espécies foi Asteraceae. As espécies destinadas à alimentação (32%) dominaram a área e as mais frequentes foram Persea americana, Psidium guajava, Carica papaya e Allium fistulosum. A maioria das espécies foi introduzida (78%), com predominância dos subarbustos (40%) e árvores (22%). O manejo dos quintais é realizado pela mulher, responsável pela introdução de novas espécies e sua diversificação tende a evoluir ao longo do tempo. A análise do Coeficiente de Importância da Espécie (CIE) permitiu indicar como potencialmente comerciais Euterpe oleracea, Annona muricata, Carica papaya, Psidium guajava e Carapa guianensis, cujo manejo deve ser favorecido dentro dos quintais, podendo haver sua introdução em lotes, otimizando o uso da terra, assegurando a segurança alimentar e agregando renda às famílias com a venda do excedente da produção.
A gestão democrática e o projeto político pedagógico na concepção do professor: um estudo de caso
Authors: Bianchin Josiane Folletto , Barichello Marta Roseli de Azeredo
Published: December 2014

Este trabalho teve por objetivo geral investigar como os docentes percebem o seu papel de gestores e como objetivos específicos compreender como ocorre a gestão democrática participativa na escola, analisar o comportamento dos professores em frente à gestão escolar, investigar a ação e contribuição dos docentes na elaboração e desenvolvimento do projeto político-pedagógico como um espaço de gestão democrática e observar a relação do projeto político-pedagógico da escola com a sua realidade. Esta investigação se baseou em questionários estruturados com perguntas abertas, aplicadas apenas aos professores do noturno do ensino médio, direção, vice-direção e coordenação pedagógica de uma escola estadual de Santa Maria, RS. Ainda que muito seja discutido sobre gestão democrática pode-se perceber que a participação dos professores, que foi o objeto de pesquisa, ainda é limitada na escola. Existem algumas formas de participação que são passivas, destacando a colaboração em festas, o ouvir e aprovar as sugestões da direção, ou até mesmo ouvir e discutir assuntos, mas não de se chegar a nenhum consenso com os demais membros escolares. Ressalta-se que esta pesquisa é, apenas, uma amostra da realidade de uma escola em um determinado período de tempo.Palavras-chave: gestão democrática, projeto político pedagógico, professor gestor.
Suporte no trabalho: a percepção de docentes do ensino técnico
Authors: Ferreira Marinês Vernônica , Tonin Stefania , Almeida Taís Corrêa , Costa Vívian , Santos Leila Maria Araújo
Published: December 2014

O estudo foi desenvolvido com o intuito de responder o seguinte problema de pesquisa: quais são as percepções de suporte no trabalho dos docentes inseridos em uma instituição de ensino técnico?  Para tanto, realizou-se um estudo de caso descritivo e de caráter quantitativo. A unidade de análise da pesquisa é composta por 17 docentes de um colégio técnico da cidade de Santa Maria, RS. Para coleta dos dados utilizou-se a escala de percepção de suporte social no trabalho (EPSST) e a escala de percepção de suporte organizacional (EPSO). Com relação ao suporte social no trabalho, observou-se que há uma maior percepção do suporte social informacional e do suporte social instrumental. Considerando o suporte organizacional, os docentes apresentam uma percepção elevada da instituição.Palavras-chave: suporte social no trabalho, suporte organizacional, ensino técnico.
Importância dos cursos extracurriculares na formação profissional dos acadêmicos do Curso Técnico em Agropecuária
Authors: Gutierrez Karina , Santos Joabel Tonellotto dos , De Cesaro Matheus Pedrotti , Rosa Paulo Roberto Antunes da , Santos Leila Maria Araújo
Published: December 2014

Cursos extracurriculares são uma oportunidade de praticar e aprender assuntos muitas vezes não abordados no decorrer de um curso. Este trabalho objetivou verificar a percepção dos discentes do início e final do Curso Técnico em Agropecuária do Colégio Politécnico da UFSM em relação aos cursos extracurriculares. Por meio de questionário foi observado que os estudantes consideram os cursos extracurriculares importantes para a formação profissional. Também foi observado que grande parte dos estudantes já participou de atividades semelhantes. Os resultados obtidos demonstram a preocupação dos alunos com o futuro profissional e também o papel fundamental de agências financiadoras de atividades na formação qualificada dos estudantes.Palavras-chave: aprendizagem, práticas, currículo, Pronatec.