bluuebunny/crossref_metadata_2025_split huggingface dataset:
Arabinogalactan proteins mark stigmatic receptivity in the protogynous flowers of Magnolia virginiana (Magnoliaceae)
Authors: Losada Juan M. , Herrero Maria , Hormaza Jose I. , Friedman William E. 
Published: October 2014

• Premise of the study: Factors affecting floral receptivity in angiosperms remain opaque, but recent studies suggest that the acquisition of stigmatic receptivity associated with cell‐wall‐related arabinogalactan proteins (AGPs) may be a widespread feature of flowering plants. Here, the time during which a stigma is receptive is evaluated and related to the secretion of AGPs in Magnolia virginiana, a protogynous member of an early‐divergent angiosperm clade (magnoliids) with a clearly discernible female receptive phase.• Methods: Magnolia virginiana flower phenology was documented, and histochemical changes in the stigma before and after pollination were examined. Stigmatic receptivity was evaluated in relation to the secretion of AGPs detected in whole mounts and immunolocalized in sectioned stigmas.• Key results: Protogynous Magnolia flowers had a precise window of stigmatic receptivity, which is concomitant with the secretion of two AGPs labeled for different epitopes. After pollen germination and tube growth, these two AGPs could no longer be detected in the stigmas, suggesting that these AGPs interact with the growing male gametophytes and could be markers of stigmatic receptivity.• Conclusions: These results show that the period of stigmatic receptivity is finely coordinated with the secretion of two arabinogalactan proteins on stigmas of flowers of M. virginiana. This first report of AGP presence in stigmatic tissues in a member of the magnoliids, together with recently described similar patterns in eudicots, monocots, and members of early‐divergent lineages of flowering plants, suggests an ancient and widespread role for AGPs on stigmatic receptivity in angiosperms.
Design, Motivation and Performance in a Cooperative MOOC Course
Authors: Castaño-Garrido Carlos , Maiz-Olazabalaga Inmaculada , Garay-Ruiz Urtza 
Published: October 2014

MOOCs are seen as the latest evolution in online learning and, since their launch in 2008, they have become an integral part of university course curricula. Despite the social success of these courses, the learning design and efficacy of their results have been questioned. Most current research has focused more on discussing their potential to offer quality, large-scale education worldwide rather than measuring learning outcomes. This paper shows the results of a research study that focused on the pedagogical design of a cooperative MOOC and its influence on motivation and academic results. A Delphi study was used to validate the design, and the motivation variable was controlled using the Instructional Materials Motivation Survey (IMMS). Academic performance was assessed through evidence-based learning. The paper argues that design, which is defined by the students’ intensive use of social networks and the activities they carry out in their Personal Learning Environments, has an influence on performance, and the variable that mediates in that relationship is the level of satisfaction with the perception of the design. The academic results obtained and the students’ motivation support the use of cooperative MOOCs in university education.Los cursos MOOC se han entendido como la última evolución del aprendizaje en red, y desde su nacimiento en 2008 se han puesto en práctica en un buen número de universidades. A pesar del éxito social de estas propuestas, tanto el diseño del aprendizaje como la eficacia de sus resultados han sido puestos en duda. Actualmente la mayoría de las publicaciones se centran más en discutir su potencial para ofrecer educación de calidad en todo el mundo a gran escala que en la medición rigurosa de los resultados de aprendizaje. El presente trabajo muestra los resultados de una investigación centrada en el diseño pedagógico de un curso MOOC cooperativo y su influencia en la motivación y en los resultados académicos obtenidos. El diseño se ha validado a través de un estudio Delphi y la variable «motivación» se ha controlado a través de un instrumento estandarizado (Instructional Materials Motivation Survey, IMMS). El rendimiento académico se ha evaluado a través de evidencias de aprendizaje. Se defiende que el diseño, definido por una utilización intensiva de redes sociales y realización de actividades por parte de los estudiantes en sus Entornos Personales de Aprendizaje, influye en el rendimiento, y es la satisfacción con la percepción del diseño la variable que media en dicha relación. Los resultados académicos obtenidos y la motivación de los estudiantes avalan la utilización de cursos MOOC cooperativos en estudios universitarios.
Challenges in the Creation, Development and Implementation of MOOCs: Web Science Course at the University of Southampton
Authors: Sánchez-Vera Maria-del-Mar , León-Urrutia Manuel , Davis Hugh 
Published: October 2014

Massive is one of the distinctive features of MOOCs which differentiate them from other e-learning experiences. This massiveness entails certain possibilities, but also some challenges that must be taken into consideration when designing and implementing a Massive Open Online Course, in relation to context, work progress, learning activities, assessment, and feedback. This document presents an analysis of the advantages and disadvantages of the massive aspect of MOOCs, and specifically it narrates the experience of creating a MOOC on Web Science, developed at the University of Southampton (United Kingdom) using the new FutureLearn platform, in autumn 2013. In this document, the importance of Web Science as an emerging field is analyzed and its origins explored. The experience gained from the decisions and the work progress developed for the creation and implementation of a specific MOOC is also shared here. The final section of the paper analyses some data from the MOOC in Web Science, including the participation index, the comments and interactions of some participants, tools used, and the organization of facilitation. Challenges involved in running a MOOC related to course design, platform use and course facilitation are also discussed.
El carácter masivo es una de las peculiaridades de los MOOC, que lo diferencian de otro tipo de experiencias de aprendizaje en red. Este hecho configura una serie de posibilidades, pero también una serie de retos que hay que tener en cuenta a la hora de diseñar e implementar un curso masivo en red, en relación, por ejemplo, a los contenidos, el proceso de trabajo, las actividades, la evaluación y el feed-back. Este trabajo presenta un análisis de las ventajas y desventajas del carácter masivo de los MOOC y concretamente describe la experiencia de creación de un MOOC sobre Web Science desarrollada en la Universidad de Southampton (Reino Unido) en la plataforma FutureLearn durante el otoño de 2013. Se analiza la importancia del estudio de la rama de Web Science y cómo se originó esta experiencia. También describen las decisiones y el proceso de trabajo desarrollado para la creación e implementación del MOOC en concreto. Se termina este trabajo analizando alguno de los datos que se han obtenido, como el índice de participación (ligeramente elevado respecto a la media de los MOOC), los comentarios de los participantes, la manera de gestionar la facilitación del curso y algunos de los retos que nos encontramos a la hora de gestionar un MOOC, que se relacionan con el diseño del curso, la plataforma que se utiliza y cómo se organiza la facilitación del curso.
Evaluation of Digital Didactic Skills in Massive Open Online Courses: a Contribution to the Latin American Movement
Authors: Hernández-Carranza Erika Elvira , Romero-Corella Sandra Irene , Ramírez-Montoya María Soledad 
Published: October 2014

The aim of this article is to present an evaluation of digital teaching skills in a project funded by the National Distance Education System (SINED) in Mexico conducted on a Massive Open Online Course (MOOC) which was designed to develop competences in teachers in the distance learning or classroom setting for the integration of open educational resources (OER). The course was conducted by the Regional Open Latin American Community for Social and Educational Research (Clarise), and posed the question: how are distance learning didactic competences using OER developed? The aim was to identify and evaluate how OER were used and the form they took throughout the stages of the open education movement. The study deployed a mixed methodology with instruments such as emailed questionnaires for the MOOC participants, viewing screens in the discussion forums and anecdotal evidence. The results show that MOOC participants were able to develop digital teaching skills, identify how to use OER and how the training process occurs in the open education movement. Constraints to the development of these skills were also seen in the acculturation in the open education movement, as well as limitations on the design of distance learning models that promote these skills and the recognition of informal learning.El objetivo de este artículo es presentar la evaluación de competencias digitales didácticas en el entorno de un proyecto financiado por el Sistema Nacional de Educación a Distancia (SINED) de México, donde se llevó a cabo un curso masivo abierto (Massive Open Online Course: MOOC, por sus siglas en inglés), dirigido a desarrollar competencias en profesores de educación a distancia o presencial para integrar recursos educativos abiertos (REA). El curso se impartió a través de la Comunidad Latinoamericana Abierta Regional de Investigación Social y Educativa (Clarise). Se partió de la interrogante ¿cómo se desarrollan las competencias didácticas en ambientes de aprendizaje a distancia que utilizan REA?, con el fin de identificar y evaluar cómo se usan los REA y cómo se está formando a través de las etapas del movimiento educativo abierto. La metodología empleada fue mixta, con instrumentos de cuestionarios electrónicos para los participantes, rejillas de observación en foros de discusión y registros anecdóticos. Los resultados muestran que los participantes en un MOOC, logran desarrollar competencias digitales didácticas, lográndose identificar claramente cómo se usan los REA y cómo se está dando el proceso de formación en el movimiento educativo abierto; sin embargo, también se denotan limitaciones para el desarrollo de estas competencias, tales como la culturización en el movimiento educativo abierto, el diseño de modelos de aprendizaje a distancia que promuevan las competencias y el reconocimiento del aprendizaje informal.
Academic Plagiarism among Secondary and High School Students: Differences in Gender and Procrastination
Authors: Sureda-Negre Jaume , Comas-Forgas Ruben , Oliver-Trobat Miquel Francesc 
Published: October 2014

This paper analyses the phenomenon of academic plagiarism among students enrolled in Secondary Education and High School. It is a subject poorly studied at pre-university level and very scantily discussed in the Spanish-speaking context. It investigates the frequency of committing plagiarism and the relationship between gender and procrastination and such practices. A questionnaire was administered to a representative sample (n=2,794). The results show that plagiarism is certainly present and widespread in the secondary classrooms. Furthermore, it shows that men have significantly higher levels of perpetration than women and than students who tend to leave the tasks until the last moment are more likely to plagiarize. The fruits of this research suggest the need to take into serious consideration the magnitude and severity of the problem identified; secondary schools should urgently plan and undertake measures in order to reduce and prevent the commission of this type of academic fraud. Secondly, results are useful to give clear guidance to teachers about the need for them to follow up and apply an effective control of the writing process of academic essays and tasks by students. Improving IT and library competences of the students has been identified as one of the main strategies needed to effectively address the problem.En este trabajo se analiza el fenómeno del plagio académico entre el alumnado de Educación Secundaria Obligatoria y Bachillerato. Se trata de un tema poco estudiado en los niveles preuniversitarios y muy escasamente tratado en el contexto hispanohablante. Se investiga la prevalencia de este fenómeno así como su relación con el género y la procrastinación. Los datos fueron obtenidos mediante la administración de un cuestionario a una muestra representativa (n=2.794). Los resultados del estudio muestran que las prácticas constitutivas de plagio están ampliamente extendidas en las aulas de los ciclos educativos medios. Además, se demuestra que los varones presentan niveles de perpetración significativamente superiores a los de las mujeres y que el alumnado que tiende a dejar los trabajos hasta el último momento tiene mayor propensión a cometer plagio. Los frutos de esta investigación sugieren la necesidad de tomar en seria consideración la magnitud y severidad del problema detectado. Los centros de educación secundaria deben proyectar y acometer de manera perentoria medidas en aras de reducir y prevenir la comisión de este tipo de fraudes académicos. Los resultados también hacen recomendable que los docentes hagan un seguimiento y un control efectivo del proceso de elaboración de los trabajos académicos. La mejora de las competencias informacionales del alumnado es señalada como una de las estrategias necesarias para encarar eficazmente el problema.
FcRγ-Chain ITAM Signaling Is Critically Required for Cross-Presentation of Soluble Antibody–Antigen Complexes by Dendritic Cells
Authors: Boross Peter , van Montfoort Nadine , Stapels Daphne A. C. , van der Poel Cees E. , Bertens Christian , Meeldijk Jan , Jansen J. H. Marco , Verbeek J. Sjef , Ossendorp Ferry , Wubbolts Richard , Leusen Jeanette H. W. 
Published: October 2014

Abstract
The uptake of Ag–Ab immune complexes (IC) after the ligation of activating FcγR on dendritic cells (DC) leads to 100 times more efficient Ag presentation than the uptake of free Ags. FcγRs were reported to facilitate IC uptake and simultaneously induce cellular activation that drives DC maturation and mediates efficient T cell activation. Activating FcγRs elicit intracellular signaling via the ITAM domain of the associated FcRγ-chain. Studies with FcRγ-chain knockout (FcRγ−/−) mice reported FcRγ-chain ITAM signaling to be responsible for enhancing both IC uptake and DC maturation. However, FcRγ-chain is also required for surface expression of activating FcγRs, hampering the dissection of ITAM-dependent and independent FcγR functions in FcRγ−/− DCs. In this work, we studied the role of FcRγ-chain ITAM signaling using DCs from NOTAM mice that express normal surface levels of activating FcγR, but lack functional ITAM signaling. IC uptake by bone marrow–derived NOTAM DCs was reduced compared with wild-type DCs, but was not completely absent as in FcRγ−/− DCs. In NOTAM DCs, despite the uptake of ICs, both MHC class I and MHC class II Ag presentation was completely abrogated similar to FcRγ−/− DCs. Secretion of cytokines, upregulation of costimulatory molecules, and Ag degradation were abrogated in NOTAM DCs in response to FcγR ligation. Cross-presentation using splenic NOTAM DCs and prolonged incubation with OVA-IC was also abrogated. Interestingly, in this setup, proliferation of CD4+ OT-II cells was induced by NOTAM DCs. We conclude that FcRγ-chain ITAM signaling facilitates IC uptake and is essentially required for cross-presentation, but not for MHC class II Ag presentation.
The Absence or Overexpression of IL-15 Drastically Alters Breast Cancer Metastasis via Effects on NK Cells, CD4 T Cells, and Macrophages
Authors: Gillgrass Amy , Gill Navkiran , Babian Artem , Ashkar Ali A. 
Published: October 2014

Abstract
IL-15 is a cytokine that can affect many immune cells, including NK cells and CD8 T cells. In several tumor models, IL-15 delays primary tumor formation and can prevent or reduce metastasis. In this study, we have employed a model of breast cancer metastasis to examine the mechanism by which IL-15 affects metastasis. When breast tumor cells were injected i.v. into IL-15−/−, C57BL/6, IL-15 transgenic (TG) and IL-15/IL-15Rα–treated C57BL/6 mice, there were high levels of metastasis in IL-15−/− mice and virtually no metastasis in IL-15 TG or IL-15–treated mice. In fact, IL-15−/− mice were 10 times more susceptible to metastasis, whereas IL-15 TG mice were at least 10 times more resistant to metastasis when compared with control C57BL/6 mice. Depletion of NK cells from IL-15 TG mice revealed that these cells were important for protection from metastasis. When NK cells were depleted from control C57BL/6 mice, these mice did not form as many metastatic foci as IL-15−/− mice, suggesting that other cell types may be contributing to metastasis in the absence of IL-15. We then examined the role of CD4 T cells and macrophages. In IL-15−/− mice, in vivo depletion of CD4 T cells decreased metastasis. The lack of IL-15 in IL-15−/− mice, and possibly the Th2-polarized CD4 T cells, was found to promote the formation of M2 macrophages that are thought to contribute to metastasis formation. This study reveals that whereas IL-15 effects on NK cells are important, it also has effects on other immune cells that contribute to metastasis.
Distinct Roles of the Anaphylatoxins C3a and C5a in Dendritic Cell–Mediated Allergic Asthma
Authors: Engelke Carsten , Wiese Anna V. , Schmudde Inken , Ender Fanny , Ströver Heike A. , Vollbrandt Tillmann , König Peter , Laumonnier Yves , Köhl Jörg 
Published: October 2014

Abstract
Conventional dendritic cells (cDC) are necessary and sufficient to drive mixed maladaptive Th2/Th17 immune responses toward aeroallergens in experimental allergy models. Previous studies suggest that the anaphylatoxin C3a promotes, whereas C5a protects from the development of maladaptive immunity during allergen sensitization. However, only limited evidence exists that such effects are directly mediated through anaphylatoxin-receptor signaling in cDCs. In this study, we assessed the impact of C3a and C5a on cDC-mediated induction pulmonary allergy by adoptively transferring house dust mite (HDM)–pulsed bone marrow–derived DCs (BMDC) from wild-type (WT) C3aR−/−, C5aR1−/−, or C3aR−/−/C5aR1−/− into WT mice. Transfer of HDM-pulsed WT BMDCs promoted a strong asthmatic phenotype characterized by marked airway resistance, strong Th2 cytokine, and mucus production, as well as mixed eosinophilic and neurophilic airway inflammation. Surprisingly, C3aR−/− cDCs induced a strong allergic phenotype, but no IL-17A production, whereas HDM-pulsed C5aR1−/− cDCs failed to drive pulmonary allergy. Transfer of C3aR−/−/C5aR1−/− cDCs resulted in a slightly reduced allergic phenotype associated with increased IFN-γ production. Mechanistically, C3aR and C5aR1 signaling is required for IL-23 production from HDM-pulsed BMDCs in vitro. Furthermore, C3aR−/− BMDCs produced less IL-1β. The mechanisms underlying the failure of C5aR1−/− BMDCs to induce experimental allergy include a reduced capability to migrate into the lung tissue and a decreased potency to direct pulmonary homing of effector T cells. Thus, we uncovered a crucial role for C5a, but only a minor role for C3a in BMDC-mediated pulmonary allergy, suggesting that BMDCs inappropriately reflect the impact of complement on lung cDC-mediated allergic asthma development.
Proprotein Convertase FURIN Constrains Th2 Differentiation and Is Critical for Host Resistance against Toxoplasma gondii
Authors: Oksanen Anna , Aittomäki Saara , Jankovic Dragana , Ortutay Zsuzsanna , Pulkkinen Kati , Hämäläinen Sanna , Rokka Anne , Corthals Garry L. , Watford Wendy T. , Junttila Ilkka , O’Shea John J. , Pesu Marko 
Published: October 2014

Abstract
The proprotein convertase subtilisin/kexin enzymes proteolytically convert immature proproteins into bioactive molecules, and thereby they serve as key regulators of cellular homeostasis. The archetype proprotein convertase subtilisin/kexin, FURIN, is a direct target gene of the IL-12/STAT4 pathway and it is upregulated in Th1 cells. We have previously demonstrated that FURIN expression in T cells critically regulates the maintenance of peripheral immune tolerance and the functional maturation of pro–TGF-β1 in vivo, but FURIN’s role in cell-mediated immunity and Th polarization has remained elusive. In this article, we show that T cell–expressed FURIN is essential for host resistance against a prototypic Th1 pathogen, Toxoplasma gondii, and for the generation of pathogen-specific Th1 lymphocytes, including Th1–IL-10 cells. FURIN-deficient Th cells instead show elevated expression of IL-4R subunit α on cell surface, sensitized IL-4/STAT6 signaling, and a propensity to polarize toward the Th2 phenotype. By exploring FURIN-interacting proteins in Jurkat T cells with Strep-Tag purification and mass spectrometry, we further identify an association with a cytoskeleton modifying Ras-related C3 botulinum toxin substrate/dedicator of cytokinesis 2 protein complex and unravel that FURIN promotes F-actin polymerization, which has previously been shown to downregulate IL-4R subunit α cell surface expression and promote Th1 responses. In conclusion, our results demonstrate that in addition to peripheral immune tolerance, T cell–expressed FURIN is also a central regulator of cell-mediated immunity and Th1/2 cell balance.
Single Sea Urchin Phagocytes Express Messages of a Single Sequence from the DiverseSp185/333Gene Family in Response to Bacterial Challenge
Authors: Majeske Audrey J. , Oren Matan , Sacchi Sandro , Smith L. Courtney 
Published: October 2014

AbstractImmune systems in animals rely on fast and efficient responses to a wide variety of pathogens. The Sp185/333 gene family in the purple sea urchin, Strongylocentrotus purpuratus, consists of an estimated 50 (±10) members per genome that share a basic gene structure but show high sequence diversity, primarily due to the mosaic appearance of short blocks of sequence called elements. The genes show significantly elevated expression in three subpopulations of phagocytes responding to marine bacteria. The encoded Sp185/333 proteins are highly diverse and have central effector functions in the immune system. In this study we report the Sp185/333 gene expression in single sea urchin phagocytes. Sea urchins challenged with heat-killed marine bacteria resulted in a typical increase in coelomocyte concentration within 24 h, which included an increased proportion of phagocytes expressing Sp185/333 proteins. Phagocyte fractions enriched from coelomocytes were used in limiting dilutions to obtain samples of single cells that were evaluated for Sp185/333 gene expression by nested RT-PCR. Amplicon sequences showed identical or nearly identical Sp185/333 amplicon sequences in single phagocytes with matches to six known Sp185/333 element patterns, including both common and rare element patterns. This suggested that single phagocytes show restricted expression from the Sp185/333 gene family and infers a diverse, flexible, and efficient response to pathogens. This type of expression pattern from a family of immune response genes in single cells has not been identified previously in other invertebrates.