bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of statistical methods for downscaling daily precipitation
Authors: Muluye Getnet Y.
Published: September 2012

There are several statistical downscaling methods available for generating local-scale meteorological variables from large-scale model outputs. There is still no universal single method, or group of methods, that is clearly superior, particularly for downscaling daily precipitation. This paper compares different statistical methods for downscaling daily precipitation from numerical weather prediction model output. Three different methods are considered: (i) hybrids; (ii) neural networks; and (iii) nearest neighbor-based approaches. These methods are implemented in the Saguenay watershed in northeastern Canada. Suites of standard diagnostic measures are computed to evaluate and inter-compare the performances of the downscaling models. Although results of the downscaling experiment show mixed performances, clear patterns emerge with respect to the reproduction of variation in daily precipitation and skill values. Artificial neural network-logistic regression (ANN-Logst), partial least squares (PLS) regression and recurrent multilayer perceptron (RMLP) models yield greater skill values, and conditional resampling method (SDSM) and K-nearest neighbor (KNN)-based models show the potential to capture the variability in daily precipitation.
RP-HPLC assay method development for Paracetamol and Lornoxicam in combination and characterization of oxidative degradation products of Lornoxicam
Authors: Jain Pritam , Patel Miketa , Chaudhari Amar , Surana Sanjay
Published: September 2012

A simple, specific, accurate and precise reverse phase high pressure liquid
chromatographic method has been developed for the simultaneous determination
of Paracetamol and Lornoxicam from tablets and to characterize degradation
products of Lornoxicam by reverse phase C18 column (Inertsil ODS 3V C-18, 250
x 4.6 mm, 5 ?). The sample was analyzed using Buffer (0.02504 Molar):
Methanol in the ratio of 45:55, as a mobile phase at a flow rate of 1.5
mL/min and detection at 290 nm. The retention time for Paracetamol and
Lornoxicam was found to be 2.45 and 9.40 min respectively. The method can be
used for estimation of combination of these drugs in tablets. The method was
validated as per ICH guidelines. The linearity of developed method was
achieved in the range of 249.09 - 747.29 ?g/mL (r2=0.9999) for Paracetamol
and 4.0125 - 12.0375 ?g/mL (r2=0.9999) for Lornoxicam. Recoveries from
tablets were between 98 and 102%. The method was validated with respect to
linearity, accuracy, precision, robustness and forced degradation studies
which further proved the stability-indicating power. During the forced
degradation studies lornoxicam was observed to be labile to alkaline
hydrolytic stress and oxidative stress (in the solution form). However, it
was stable to the acid hydrolytic, photolytic and thermal stress (in both
solid and solution form). The degraded products formed were investigated by
electrospray ionization (ESI) time-of-flight mass spectrometry, NMR and IR
spectroscopy. A possible degradation pathway was outlined based on the
results. The method was found to be sensitive with a detection limit of 0.193
?g/ml, 2.768 ?g/ml and a quantitation limit of 0.638 ?g/ml, 9.137 ?g/ml for
lornoxicam and paracetamol, respectively. Due to these attributes, the
proposed method could be used for routine quality control analysis of these
drugs in combined dosage forms.
Problems Faced by Distance Learners in Using Web-Based Facilities
Authors: Dharankar Madhavi
Published: September 2012

Countries like India are engaged in exploring appropriate ways of tackling the urgent problem of educating their large and growing populations in relatively little time and with limited resources. Against this background, achieving universal primary education is a major concern. If this Millennium Development Goal is to be achieved, the empowerment of teachers is necessary. Considering the large number of such personnel to be trained, educationists have turned their attention to open and distance learning. In distance education methods, educationists now acknowledge the liberating possibilities of non-print media, which have the potential to surmount physical obstacles, as well as break the constraints of traditional classroom teaching. The development of information and communication technologies has spawned a number of innovations in open and distance learning. In the School of Education at Yashwantrao Chavan Maharashtra Open University, there have been attempts to bring about transformation by using innovative approaches. Creating discussion forums in the regional language is an innovation that has been used and tested. Experimentation and research in this regard has been conducted for the past three years. This article shares the various experiments that have been attempted, the strategies that have been adopted, the results of these experimentations and the lessons that have been learned thereby.
Learning with Web 2.0: Social Technology and Discursive Psychology
Authors: Friesen Norm , Lowe Shannon
Published: September 2012

Recent years have seen the rise of Internet technologies which facilitate activities that are, above all, social and participatory, allowing children and adults to create and share their own content, and to communicate in a wide range of forums. Correspondingly, there has been great popular and expert interest in the potential of Web 2.0 communication technologies for education. The discursive ‘spaces' enabled by Web 2.0 differ from conventional face-to-face and online educational environments in that communication largely occurs in the written form, and is informal and abbreviated. To understand the potential of these new ‘conversational’ communicative practices and technologies for formal education calls for a new research approach: one that focuses on learning through text-based, informal communication. Such a research approach has been proposed by discursive psychology, a social psychological paradigm that emerged in the 1990s which combines the insights of phenomenology, ethnomethodology and conversational analysis. The concern of this approach and of its theoretical precursors with ‘sense-making’ has been observed by educational technologists to make it clearly suitable to a study of instructional practice. This article provides an account of this discursive approach in terms of its relevance to education and applicability for new technologies. With these two key factors in mind, the article suggests how discursive psychology can be adapted in the study of Web 2.0 technologies in educational contexts.
Online Learning in Divorce: How the Formation of a Community of Practice in a Divorce Support Website Enables and Inhibits Learning
Authors: Paechter Carrie
Published: September 2012

This article is about the informal learning that took place in an online divorce support and advice forum. In it, the author discusses the formation of a community of practice among the members during the first nine months of the site's operation. The author shows how the key markers of mutual engagement, joint enterprise and shared repertoire developed between members, and argues that the community of practice both enhanced and inhibited learning among its members. In particular, the author suggests that members learned not only the knowledge about divorce law provided by others on the site as a form of public good, but they also learned ways of coping with divorce, with their ex-spouse and with the legal system generally. At the same time, however, some group practices inhibited learning, both for those participating in the community and for those excluded by members. The author concludes with suggestions for developing similar online communities of practice.
(Information) Technologies of the Self: Personalisation as a New Mode of Subjectivation and Knowledge Production
Authors: Rensfeldt Annika Bergviken
Published: September 2012

Personalisation has increasingly become a concern in policy making, public service, information technology (IT) provision and academic traditions. This article is concerned with how personalisation and personalised learning are suggested to reform Swedish higher education. The empirical material is official documents from the Swedish policy process of flexible education from 1998 onwards, including the universities' replies to these proposals and the following government bill. Moreover, material on learning management systems from public instances has been included. Personalisation is regarded as part of a contemporary intensified mode of governing that makes use of liberal powers and self-government, where individuals are governed and preferably govern themselves through IT-based modes of learning. Specifically, the article examines how personalisation – as a mode of subjectivation inscribed in Swedish education policies – is constituted by two particular and intertwined technologies of government: the IT-based learning environment and self-technologies. The author's argument is that this creates a productive and personalised apparatus, made possible through ethical self-constitution in IT-mediated learning environments and an ideal performative knowledge production. Questions are raised about the possible limitations of the social and informational action of such an apparatus, and risks of exposure and connectivity in these self-governable learning environments.
Challenges of Employing E-Learning for Teaching Language: A Case of Teaching English in Iran
Authors: Alizadeh Iman
Published: September 2012

The whole thrust of this study was to delve into some of the pedagogical and practical challenges intimately related to employing e-learning for teaching language. To this aim, 30 language learners targeted as the subjects of the study were randomly assigned into experimental and control groups after administering a pretest. One the one hand, the control group experienced the conventional classroom practices common in most language institutes. On the other hand, the experimental group went through an electronically mediated language course. The whole study was carried out during a summer course. At the end of the course, students' productive and receptive language skills in both groups were checked. As for the productive skills, the analysis of the data revealed that the experimental group had performed far better than the control group in the writing modality, but the control group had outperformed in the speaking modality. The findings also signalled no significant difference regarding listening skills, which were targeted as the receptive skill. With respect to the findings of the study and the subjects' feedback on the strengths and weaknesses of the e-course, the study shed light on some of the practical and pedagogical drawbacks of employing e-learning for teaching language skills. As a way out of the existing problems, some solutions were proposed. The study has significant implications for stakeholders involved in electronically mediated teaching and learning practices.
Learning by E-Learning for Visually Impaired Students: Opportunities or Again Marginalisation?
Authors: Kharade Kalpana , Peese Hema
Published: September 2012

In recent years, e-learning has become a valuable tool for an increasing number of visually impaired (VI) learners. The benefits of this technology include: (1) remote learning for VI students; (2) the possibility for teachers living far from schools or universities to provide remote instructional assistance to VI students; and (3) continuing education for VI adults. A number of studies confirm that VI students appreciate the advantages of e-learning systems, but they also have to face several challenges in pursuing their education through the e-learning mode. E-learning can be a valuable opportunity for VI users if suitable education methods and appropriate technologies are used. Hence, it is crucial to identify the needs and requirements of the target community in order to create a system that fulfils their expectations. This article describes the experiences of Indian VI learners with e-learning, throws light on the problems often encountered by them when using assistive technology and proposes guidelines for designers in order to develop more accessible e-learning systems.
Effective Tool or Effectively Hollow? Balanced Budget Legislation in Western Canada
Authors: SIMPSON WAYNE , WESLEY JARED J.
Published: September 2012

Il y a maintenant une vingtaine d’années que les premières lois d’équilibre budgétaire ont été adoptées au Canada. Cette période de temps suffisante ainsi que le ralentissement économique des dernières années créent des conditions qui permettent maintenant aux chercheurs d’analyser les effets de ces lois, dont l’objectif était d’inciter les gouvernements à une plus grande responsabilité financière. Dans cet article, nous analysons l’impact que ces lois ont eu dans les quatre provinces de l’Ouest. Notre analyse est à la fois quantitative – nous évaluons les effets des lois sur la croissance des dépenses – et qualitative – la récession de 2008-2009 ayant constitué le premier grand test pour ces lois depuis leur mise en place. Nous concluons que les lois d’équilibre budgétaire n’ont pas vraiment permis d’atteindre les objectifs fixés au départ. Notre analyse empirique montre en effet qu’elles n’ont pas permis en période de santé économique de limiter la croissance des dépenses par rapport aux revenus dans la plupart des provinces, et que celles-ci se sont donc retrouvées dans une situation de vulnérabilité quand est arrivée la récession. En d’autres mots, les lois d’équilibre budgétaire n’ont été assez solides ni pour assurer la réduction de la croissance des dépenses quand tout allait bien, ni pour éviter que les gouvernements ne choisissent de faire des déficits en période de récession. Notre analyse suggère que, comme toute loi, les lois d’équilibre budgétaire ne sont efficaces que si elles sont portées par une volonté politique et le soutien de la population.
Persistence and Academic Success in University
Authors: DOOLEY MARTIN D. , PAYNE A. ABIGAIL , ROBB A. LESLIE
Published: September 2012

Dans cet article, nous examinons, à l’aide d’un ensemble de données couplées, les déterminants de la persévérance et de la réussite scolaires à l’université. Parmi ces déterminants, les notes obtenues au secondaire jouent un rôle nettement plus importants que la nature du programme universitaire, le sexe, l’entourage et les caractéristiques de l’école secondaire fréquentée. Le revenu moyen dans l’entourage et le classement de l’école secondaire fréquentée à des tests standardisés ont ainsi peu de liens avec la réussite à l’université. Ces résultats soulèvent des questions intéressantes sur ce qui permettrait d’expliquer la variation des notes à l’école secondaire et sur la combinaison de facteurs – liés à l’individu, à la famille et à l’école secondaire fréquentée – qui influe sur les résultats à l’université.
Taux de change et décisions d’investissement au Canada: une analyse réalisée au niveau des emplacements
Authors: DA SILVA LAURENT , VINCENT NICOLAS
Published: September 2012

Canada has long suffered from weak investment rates in capital goods relative to the United States. We study the relationship between exchange rate fluctuations and investment by using a rich panel data set at the level of the plant. Results show that all else being equal, Canadian firms on average tend to reduce their investment activity following an appreciation of the Canadian dollar. Moreover, the most affected firms are those that export a larger share of their output. This supports the hypothesis that following an appreciation of the currency, the negative impact on the competitiveness of domestic firms outweighs the benefits through increased purchasing power.
Applying European Ideas on Federalism and Doing It Better? The Government of Canada’s Homelessness Policy Experiment
Authors: DOBERSTEIN CAREY
Published: September 2012

Même s’il n’a pas de façon explicite autorité pour légiférer dans ce domaine, le gouvernement fédéral a, en 2000, mis sur pied l’Initiative nationale pour les sans-abri. Dans cet article, j’avance que ce programme fédéral ressemble beaucoup, dans plusieurs de ses aspects fondamentaux, à un modèle de gouvernance conçu par l’Union européenne et appelé « méthode ouverte de coordination » (MOC). Le contexte institutionnel dans lequel ce modèle a été créé est intéressant, parce que, si la Commission européenne n’a pas formellement autorité pour obliger les membres de l’Union à coordonner leurs politiques sociales, elle utilise néanmoins des mécanismes non contraignants ou de nature volontaire pour tenter d’y arriver. Pour démontrer dans la pratique la flexibilité du programme fédéral canadien, qui ressemble à la MOC, ainsi que ses implications en matière de gouvernance, d’obligation de rendre des comptes et d’efficacité, j’analyse de plus près les cas de Vancouver et de Toronto. J’en conclus que, alors que la solution du problème de l’itinérance se bute constamment à un manque de financement stable, une application des principes du modèle MOC – adapté à la situation canadienne – pourrait permettre d’améliorer la gestion, la coordination et l’efficacité des politiques publiques liées à l’itinérance, et que cette question devrait donc attirer l’attention des décideurs politiques et des chercheurs qui s’intéressent au fédéralisme canadien.
The Canada-US Unemployment Rate Gap: A New Look with a New Decomposition for Cross-Country Differences in Unemployment Rates
Authors: CAMPOLIETI MICHELE
Published: September 2012

Dans cet article, je présente une décomposition des variations de l’écart entre les taux de chômage canadien et américain, en utilisant comme mesures les taux d’« entrée » en chômage (inflow hazard) et de « sortie » du chômage (outflow hazard). Mes estimations montrent que la plupart des variations de l’écart entre 1981 et 2009 sont dues à des changements au niveau de la « sortie » du chômage (autrement dit, dans la durée des périodes de chômage). L’importance relative des effets de ces deux phénomènes (« entrée » et « sortie ») sur l’écart des taux de chômage a varié avec le temps, mais c’est la « sortie » qui, depuis 1997, explique le plus grand nombre de changements dans l’écart entre les taux de chômage.
Meat and Global Warming: Impact Models, Mitigation Approaches and Ethical Aspects
Authors: Nordgren Anders
Published: September 2012

In this paper, I investigate the ethical problem of mitigation of climate change, to the extent this change is caused by animal production. First, I give an overview of various views of the nature and scale of the impact of animal production on climate change: the life cycle model, the complex impact model and the additional emissions model. Second, I analyse various approaches to mitigation of climate change to the extent it is caused by animal production, such as different technological solutions and more or less radical proposals for reduction of livestock numbers. Third, I carry out a preliminary investigation of ethical aspects to be taken into consideration in assessing the mitigation approaches: intergenerational justice, intragenerational justice, animal welfare, potential, and feasibility. Finally, I propose a kind of ‘contraction and convergence’ policy, i.e., a policy of reducing meat consumption to a certain level in developed countries while allowing people in developing countries to increase their consumption up to this level.
Falling, Looking, Caring:Red Roadas Melodrama
Authors: Stewart Michael
Published: September 2012

This article examines Red Road as a melodrama and woman's film. It argues that the film is traductively real and melodramatic, and that conceiving the film in melodramatic terms is contrary to the way in which it has been defined in public discourses and academic analysis. Red Road is film melodrama in a number of related ways, via: tropes of narrative and character; a tendency to look back, work through and act out in a melancholy and melodramatic fashion; an emphasis on familialism and redemption; and the nomination of its central character as a woman and mother. Red Road is a maternal text in familiar and complex ways – for example, in the way in which CCTV is inscribed with guardianship and care, and also via Jackie's presentation as a sexual and narrative riddle and other-worldly figure. Jackie's sphinx-like status, the paper argues, connects with Red Road's multiple and twilight qualities, and this is supported by the film's affective elements, including its treatment of the Red Road flats. This treatment helps to engender Red Road's qualities not only of redemption and rebirth, but also of memory and revision.
Circles, Columns and Screenings: Mapping the Institutional, Discursive, Physical and Gendered Spaces of Film Criticism in 1940s London
Authors: Selfe Melanie
Published: September 2012

This article revisits the period considered within ‘The Quality Film Adventure: British Critics and the Cinema 1942–1948’ ( Ellis 1996 ), mapping the professional cultures, working contexts and industry relationships that underpinned the aesthetic judgements and collective directions which John Ellis observed within certain film critics’ published writings. Drawing on the records of the Critics’ Circle, Dilys Powell's papers and Kinematograph Weekly, it explores the evolution of increasingly organised professional cultures of film criticism and film publicity, arguing that the material conditions imposed by war caused tensions between them to escalate. In the context of two major challenges to critical integrity and practice – the evidence given by British producer R. J. Minney to the 1949 Royal Commission on the Press and an ongoing libel case between a BBC critic and MGM – the spaces of hospitality and film promotion became highly contested sites. This article focuses on the ways in which these spaces were characterised, used and policed. It finds that the value and purpose of press screenings were hotly disputed, and observes the way that the advancement of women within one sector (film criticism) but not the other (film publicity) created particular difficulties, as key female critics avoided the more compromised masculine spaces of publicity, making them harder for publicists to reach and fuelling trade resentment. More broadly, the article asserts the need to consider film critics as geographically and culturally located audiences who experience films as ‘professional’ viewers within extended and embodied cultures of habitual professional practice and physical space.
Structure and Composition of Leachfield Bacterial Communities: Role of Soil Texture, Depth and Septic Tank Effluent Inputs
Authors: Amador Jose A. , Atoyan Janet A.
Published: September 2012

Although groundwater quality depends on microbial processes in the soil treatment area (STA) of onsite wastewater treatment systems (OWTS), our understanding of the development of these microbial communities is limited. We examined the bacterial communities of sand, sandy loam, and clay STAs at different depths in response to septic tank effluent (STE) addition using mesocosms. Terminal restriction fragment length polymorphism (TRFLP) analysis was used to compare the bacterial community structure and composition of STE, native soil prior to STE addition (UNX) and soil exposed to STE (EXP). Principal component analysis separated communities with depth in sand but not in sandy loam or clay. Indices of richness, diversity, and evenness followed the order: sandy loam > sand > clay. Analysis of TRF peaks indicated that STE contributed least to the composition of STA bacterial communities (5%–16%), followed by UNX soil (18%–48%), with the highest proportion of the community made up of TRFs not detected previously in either UNX or STE (50%–82%) for all three soils. Soil type and depth can have a marked effect on the structure and composition of STA bacterial communities, and on the relative contribution of native soil and STE to these communities.
Trajectories of engagement: a repeated cross-sectional investigation of student perceptions of an online learning environment
Authors: Palmer Stuart , Holt Dale
Published: September 2012

Evaluations of online learning environments (OLEs) often present a snapshot of system use. It has been identified in the literature that extended evaluation is required to reveal statistically significant developments in the evolution of system use over time. The research presented here draws on student OLE evaluations surveys run over the period 20042011 and include nearly 6800 responses exploring students’ perceptions of importance of, and satisfaction with elements of their OLE. Across the survey period, satisfaction ratings with all OLE elements rose significantly, suggesting a positive student engagement with the OLE over time. The corresponding ratings of importance of OLE elements generally rose significantly, though a number of elements registered no significant difference in the first two years of the survey, suggesting that short period surveys may struggle to reveal statistically significant trends. OLE element use appeared to be closely linked to perceived value. The OLE elements with the highest mean importance and satisfaction ratings related to student access of online learning resources. Other detailed results are also reported. We demonstrate a method for, and one large-scale case study of, quantifying and visualising the trajectories of engagement that students have had with an institutional OLE over time.Keywords: online learning environment; learning management system; repeated cross-sectional evaluation; student survey(Published: 24 September 2012)Citation: Research in Learning Technology 2012, 20: 17143 - http://dx.doi.org/10.3402/rlt.v20i0.17143
Students and recorded lectures: survey on current use and demands for higher education
Authors: Gorissen Pierre , Van Bruggen Jan , Jochems Wim
Published: September 2012

Online recordings of lectures provide students with anytime-anyplace access to lectures. Research shows that students prefer courses accompanied by online recordings and an increasing number of universities provide recorded lectures. This paper presents the results of a study into the use of recorded lectures at two universities in the Netherlands. The goal of the study is to gain a better understanding of the way that this group of students use recorded lectures. This understanding will enable the creation of usage scenarios that need to be supported. Our results show that students use recorded lectures as a replacement for missed lectures and for study tasks, like preparing for an exam. A large proportion of the students report that they watch 75100% of a recorded lecture when the view one. The fact that students did not mention the quality of the actual lectures appears not to influence the use of the recorded lectures. Recorded lectures for courses that only use the blackboard are viewed less often. There are also interesting differences in the use of recorded lectures of the different groups of students at the two universities. To increase the credibility and validity of the results, we need a more direct way to measure the use of recorded lectures by students. Methodological triangulation using the log data for the recorded lectures can provide this.Keywords: recorded lectures; web lectures; online lectures; video lectures(Published: 24 September 2012)Citation: Research in Learning Technology 2012, 20: 17299 - http://dx.doi.org/10.3402/rlt.v20i0.17299
Perceptions of undergraduate Graphic Design students on the educational potential of Facebook
Authors: Souleles Nicos
Published: September 2012

The popularity of Facebook among university students inevitably raises questions on the educational potential of this Social Networking Site for Higher Education. From the limited literature on the instructional uses of Facebook, one can draw conflicting conclusions. Benefits were identified through the communicative potential, student participation in study groups and through informal learning, i.e. learning that takes place outside the formal structures of the learning environment. In contrast, it is also argued that the instructional benefits of Facebook are not straightforward. This phenomenographic investigation examines the perceptions of undergraduate Graphic Design students in a higher education institution in Cyprus, on the use of Facebook for teaching and learning. Characteristic of Art and Design education is the centrality of the studio and student self-reflection. Despite some literature that considers Facebook provides a viable alternative to the physical studio, the participants in this investigation expressed a preference for face-to-face instruction and consider Facebook as complimenting rather than replacing studio practices. Some participants benefited from the use of Facebook by joining support groups and exploring information relevant to their studies. Further research can investigate how Facebook can be embedded in studio-based teaching and learning.Keywords: Facebook; Graphic Design; teaching and learning; informal learning; studio(Published: 24 September 2012)Citation: Research in Learning Technology 2012, 20: 17490 - http://dx.doi.org/10.3402/rlt.v20i0.17490
Assessment choices to target higher order learning outcomes: the power of academic empowerment
Authors: McNeill Margot , Gosper Maree , Xu Jing
Published: September 2012

Assessment of higher order learning outcomes such as critical thinking, problem solving and creativity has remained a challenge for universities. While newer technologies such as social networking tools have the potential to support these intended outcomes, academics’ assessment practice is slow to change. University mission statements and unit outlines may purport the value of higher order skills; however, questions remain about how well academics are equipped to design their curriculum and particularly their assessment strategies accordingly. This paper reports on an investigation of academic practice in assessing higher order learning in their units. Despite their intentions towards higher order learning outcomes for their students, the results suggest academics may make decisions when planning their assessment tasks that inadvertently lead students on the path towards lower order outcomes. Among the themes to emerge from the study is the importance of academics’ confidence and their attitudes towards the role of assessment in learning and how these perspectives, along with the types of learning outcomes they intend for their students, can influence their task design.Keywords: assessment; higher order learning; educational technologies; curriculum alignment; confidence(Published: 24 September 2012)Citation: Research in Learning Technology 2012, 20: 17595 - http://dx.doi.org/10.3402/rlt.v20i0.17595
Investigating uses and perceptions of an online collaborative workspace for the dissertation process
Authors: Rockinson-Szapkiw Amanda J.
Published: September 2012

The intent of this study was to investigate 93 doctoral candidates’ perceptions and use of an online collaboration workspace and content management server, Microsoft Office SharePoint, for dissertation process. All candidates were enrolled in an Ed.D. programme in the United States. Descriptive statistics demonstrate that candidates frequently use SharePoint for a variety of reasons, including assisting them in sharing and gaining information, improving the flow and organisation of the dissertation process and collaborating with their advisors mentors, in the dissertation process. Results of the multivariate analysis of variance demonstrated that doctoral students’ who extensively use SharePoint have significantly higher student-to-student connectedness and student-to-advisors connectedness than doctoral students who use it moderately and on a limited basis. Additional results revealed that sense of connectedness and satisfaction are positively associated with the different features of SharePoint. Since using SharePoint to facilitate the mentorship during the dissertation process is positively associated with connectedness and satisfaction, it may positively influence completion and time to completion of a doctoral programme.Keywords: doctoral education; computer-mediated communication; cooperative/ collaborative learning; distance education(Published: 24 September 2012)Citation: Research in Learning Technology 2012, 20: 18192 - http://dx.doi.org/10.3402/rlt.v20i0.18192
EDITORIAL: Accessibility: the killer app of learning technology?
Authors: Sharpe Rhona
Published: September 2012

As I come to the end of my term as editor, I have been reflecting on the questions I have been asked in this role. Other than ‘‘will you publish my paper?’’, the most common question has been ‘‘what’s the benefit of technology?’’ For institutions, teams and individuals who have invested money and time in keeping up with new technologies, this is an important question. I have largely skirted around an answer, talking about my desire to see more sophisticated research questions and the need to understand the context in which one is operating. From my own experience, I have seen technology prompting numerous minor improvements in many places. This is largely due to the need, when introducing any change to teaching, to rethink and redesign the teaching and assessment (Dempster, Benfield, and Francis 2012). Technology often prompts such redesign, and the value of successions of changes that feed through into our local course-improvement cycles are not to be underestimated. Frameworks for understanding such cycles of improvement, such as Ellis and Goodyear’s (2009) ecological approach (which foregrounds the relationship between student experience and institutional context), recognise the complexity of the systems in which we operate.(Published: 24 September 2012)Citation: Research in Learning Technology 2012, 20: 19584 - http://dx.doi.org/10.3402/rlt.v20i0.19584
Mesenchymal Stem Cell Population Isolated from the Subepithelial Layer of Umbilical Cord Tissue
Authors: Patel Amit N. , Vargas Vanessa , Revello Patricia , Bull David A.
Published: September 2012

The therapeutic use of stem cells to treat diseases and injuries is a promising tool in regenerative medicine. The umbilical cord provides a rich source of stem cells; we have previously reported a population of stem cells isolated from Wharton's jelly. In this report, we aimed to isolate a novel cell population that was different than those found in Wharton's jelly. We isolated stem cells from the subepithelial layer of the umbilical cord; the cells could be expanded for greater than 90 population doubling and had mesenchymal stem cell characteristics, expressing CD9, SSEA4, CD44, CD90, CD166, CD73, and CD146 but were negative for STRO-1. The cells can be directionally differentiated and undergo osteo-, chondro-, adipo-, and cardiogenesis. In addition, we have identified for the first time that mesenchymal stem cells isolated from umbilical cord can produce microvesicles, termed exosomes. This is the first report describing a stem cell population isolated from the subepithelial layer of the umbilical cord. Given the growth capacity, multilineage potential, and most importantly the low levels of HLA-ABC, we propose that this novel cell isolated from the subepithelial layer of umbilical cord is an ideal candidate for allogeneic cell-based therapy.
Serum-Free Medium and Mesenchymal Stromal Cells Enhance Functionality and Stabilize Integrity of Rat Hepatocyte Spheroids
Authors: Bao Ji , Fisher James E. , Lillegard Joseph B. , Wang William , Amiot Bruce , Yu Yue , Dietz Allan B. , Nahmias Yaakov , Nyberg Scott L.
Published: September 2012

Long-term culture of hepatocyte spheroids with high ammonia clearance is valuable for therapeutic applications, especially the bioartificial liver. However, the optimal conditions are not well studied. We hypothesized that liver urea cycle enzymes can be induced by high protein diet and maintain on a higher expression level in rat hepatocyte spheroids by serum-free medium (SFM) culture and coculture with mesenchymal stromal cells (MSCs). Rats were feed normal protein diet (NPD) or high protein diet (HPD) for 7 days before liver digestion and isolation of hepatocytes. Hepatocyte spheroids were formed and maintained in a rocked suspension culture with or without MSCs in SFM or 10% serum-containing medium (SCM). Spheroid viability, kinetics of spheroid formation, hepatic functions, gene expression, and biochemical activities of rat hepatocyte spheroids were tested over 14 days of culture. We observed that urea cycle enzymes of hepatocyte spheroids can be induced by high protein diet. SFM and MSCs enhanced ammonia clearance and ureagenesis and stabilized integrity of hepatocyte spheroids compared to control conditions over 14 days. Hepatocytes from high protein diet-fed rats formed spheroids and maintained a high level of ammonia detoxification for over 14 days in a novel SFM. Hepatic functionality and spheroid integrity were further stabilized by coculture of hepatocytes with MSCs in the spheroid microenvironment. These findings have direct application to development of the spheroid reservoir bioartificial liver.
Toward Defining the Regenerative Potential of Olfactory Mucosa: Establishment of Schwann Cell-Free Adult Canine Olfactory Ensheathing Cell Preparations Suitable for Transplantation
Authors: Ziege Susanne , Baumgärtner Wolfgang , Wewetzer Konstantin
Published: September 2012

Olfactory mucosa (OM)-derived olfactory ensheathing cells (OECs) are attractive candidates for autologous cell transplantation-based therapy of nervous system injury. However, defining the regenerative capacity of OM-derived OECs is impeded by the fact that cell cultures used for transplantation may contain significant amounts of contaminating trigeminal nerve Schwann cells that escape identification by sharing in vitro expression of OEC markers. The aim of the present study, therefore, was to quantify contaminating Schwann cells in OEC preparations and to develop a protocol for their specific depletion. Based on the observation that freshly dissociated, but not cultured, OECs and Schwann cells display differential expression of HNK-1 and p75NTR, magnet-activated cell sorting (MACS) was used to deplete myelinating (HNK-1-positive) and nonmyelinating (p75NTR-positive) Schwann cells from primary cell suspensions containing HNK-1-/p75NTR-negative OECs. Upregulation of p75NTRexpression in OECs during culturing allowed their subsequent MACS-based separation from fibroblasts. Immunofluorescence analysis of freshly dissociated OM prior to MACS depletion revealed that 21% of the total and 56% of all CNPase-positive cells, representing both OECs and Schwann cells, expressed the Schwann cell antigens HNK-1 or p75NTR, indicating that freshly dissociated OM prior to culturing contained as many Schwann cells as OECs, while olfactory bulb (OB) primary cell suspensions revealed lower levels of Schwann cell contamination. Interestingly, neurite growth of neonatal rat dorsal root ganglion (DRG) neurons cocultured with OM-OECs, OB-OECs, and fibular nerve (FN) Schwann cells used as control was significantly higher in the presence of OECs than of Schwann cells. The first report on identification and specific depletion of Schwann cells from OEC preparations provides a solid basis for future efforts to fully define the regenerative potential of nasal mucosa OECs.
Exploration of the in vitro Antiviral Activity of a Series of New Pyrimidine Analogues on the Replication of HIV and HCV
Authors: Jafar Nadhir NA , Al-Masoudi Najim A , Baqir Sadiq J , Leyssen Pieter , Pannecouque Christophe
Published: September 2012

Background:

In continuation of our search for new anti-HIV and anti-HCV agents, the suggestion, synthesis and structure elucidation of a new series of 2,6-diamino-4-alkylthio- or (2-benzylhydrazinyl)-5- p-chlorophenylazopyrimidines), 2,6-diamino-4-(2-benzylhydrazinyl)-5-(aryl-[1,1′-biphenyl]-4-yl)pyrimidines, 2,6-diamino-4-(aryl)-5-(aryl[1,1′-biphenyl]-4-yl) pyrimidines), 6-(aryl)-1,3-dimethyl-5-nitro pyrimidine-2,4-dione and 6-amino-4-methoxy- N,N-dimethyl-6-arylpyrimidines were described.

Methods:

The anti-HIV-1 (strain IIIB) and HIV-2 (strain ROD) activity of the newly synthesized pyrimidine analogues was evaluated in vitro in human MT-4 cells using the MT-4/MTT assay. Similarly, the same compounds were evaluated in vitro for their selective antiviral activity against HCV in the Huh 5–2 replicon system (type 1b, Con1 strain).

Results:

None of the tested compounds exhibited inhibition of HIV-1 and HIV-2 replication in cell culture. Even though many compounds yielded a 50% effective concentration in the HCV replicon system with selectivity indexes up to 6.9, none of the compounds matched the selection criteria of a selective inhibitor of virus replication in this assay (that is, >70% inhibition at concentrations that do not elicit an anti-metabolic effect on the host cells).

Conclusions:

Structural modification of these compounds might optimize their anti-HCV activity by introducing diverse and potent functional groups at the pyrimidine backbone, like nitrile residue. Because of the nature of the molecules, these new derivatives will also be evaluated for their potential anti-HIV activity.
Hétérogénéité des corpus et textométrie
Authors: Pincemin Bénédicte
Published: September 2012

L’homogénéité fait partie des critères habituellement requis en linguistique de corpus. Ce critère est à discuter en regard d’autres critères concernant également la textualité, comme la représentativité et l’interprétabilité ; et sa mise en œuvre suppose une définition pragmatique des genres textuels. Au stade de l’analyse, la méthode textométrique, statistique et endogène, modélisant le corpus à partir des distributions de ses unités lexicales, est directement sensible aux hétérogénéités. Mais la tradition textométrique est aussi particulièrement attentive à la forme originale des données. Aussi la textométrie a-t-elle développé des pratiques méthodologiques et mis au point des fonctionnalités pour gérer l’hétérogénéité des corpus, évitant des opérations de réduction a priori .
De l'émergence à l'impact social des discours : hétérogénéités d'un corpus
Authors: Cislaru Georgeta , Sitri Frédérique
Published: September 2012

Nous discuterons dans cet article de la constitution d’un corpus de rapports éducatifs relevant du champ de la protection de l’enfance dont nous montrerons le caractère nécessairement complexe et hétérogène. Se situant dans le cadre de l’analyse du discours, notre réflexion vise à apporter quelques éléments de réponse à la question des limites et de l’homogénéité d’un corpus, notamment du point de vue des objectifs interprétatifs de la discipline. Cette question sera abordée par le biais de la contextualisation du corpus en tant que démarche de construction d’un savoir sur le domaine, de la prise en compte des déterminations interdiscursives dont la matérialité langagière constitue la trace et enfin de l’analyse génétique de brouillons de rapports éducatifs, qui rend compte de l’inscription de contraintes diverses au fil du processus d’écriture.
Construire et maîtriser l'hétérogénéité par la variation des données, des corpus et des méthodes
Authors: Garric Nathalie
Published: September 2012

L’hétérogénéité est définie comme une ressource à construire méthodologiquement par la mise en œuvre d’un principe de variation systématique appliqué aux données, aux corpus, aux méthodes et à l’interprétation des résultats. Elle est posée comme une condition d’accès à l’espace interdiscursif d’une formation discursive, dont la saisie est elle-même nécessaire à la compréhension de certains faits socio-historiques. Ces considérations sont développées à l’aide d’une étude de cas consacrée à l’analyse des différentes issues de la formation en alternance, notamment à celle des cas de rupture de contrat d’apprentissage. L’analyse porte sur les discours suscités d’apprentis et de maîtres d’apprentissage au cours de leur expérience de formation.
Hétérogénéité et extraction d'information factuelle dans un corpus de récits de voyage
Authors: Lefeuvre Anaïs , Vinogradova Natalia
Published: September 2012

L’extraction d’information nécessite une connaissance des objets à extraire. Nous cherchons dans ce travail à décrire le comportement des séquences textuelles présentant l’itinéraire au sein du récit de voyage. Le récit de voyage est reconnu comme genre hétérogène, nous analysons donc cette hétérogénéité afin de pouvoir reconnaître les séquences homogènes, dont la description d’itinéraire fait partie. Nous menons notre analyse à plusieurs niveaux discursifs, ce qui nous permet d’avoir une vision globale du comportement de notre objet d’étude, l’itinéraire et du contexte dans lequel il apparaît. Dans la perspective de l’extraction automatique d’itinéraire, nous utilisons de nombreux outils, chacun adapté au mieux au niveau d’analyse traité. En nous appuyant sur le cadre théorique de la SRDT (Segmented Discourse Representation Theory) , dont nous montrons l’adéquation à l’étude, nous approchons le fonctionnement des descriptions des itinéraires, nous poussant à enrichir la méthode d’extraction afin de gérer l’hétérogénéité des unités discursives dans lesquels l’itinéraire est énoncé.
Rouges du Languedoc
Authors: Bonnet Jean-Louis H.
Published: September 2012

Sollicité par le seigneur et abbé de Caunes, le sculpteur génois Sormano rouvre des carrières de marbre, dans les années 1610. Six maîtres italiens s’installent à Caunes et font envoyer les marbres du Languedoc à Carrare, de même qu’ils font transporter du marbre blanc depuis l’Italie. Vers 1658, un architecte français, Jean Baux, se charge de fournir des pièces sculptées aux églises du sud-ouest, seul ou en association avec les marbriers italiens. L’importance des commandes pour les bâtiments royaux favorise le sculpteur caunois et provoque l’arrivée de nombreux travailleurs du marbre, du sculpteur à l’ouvrier. Les documents d’archives permettent de mettre en valeur la situation privilégiée des carrières de Caunes et de Félines, de préciser les moyens de transport et les techniques, d’analyser le rôle des intermédiaires dans le commerce vers l’Italie et les Bâtiments du roi.
Du vent pour scier le marbre
Authors: Claude Sandrine
Published: September 2012

Au cœur des Causses, à quelques kilomètres à l’est de Félines en Minervois, un moulin à scier le marbre s’insère dans une zone d’extraction du marbre griotte : on y en repère plusieurs carrières et sondages d’exploitation, des habitations de carriers et un chemin de charroi pour les blocs dégrossis. Le moulin, qui se dresse sur un socle artificiel aménagé en bordure d’une éminence naturelle, est entièrement réalisé à partir des déchets de taille de la carrière contiguë. Surprenante est ici l’utilisation de l’énergie éolienne pour activer le mécanisme, aujourd’hui disparu, des scies lisses qui entraînent du sable et, par abrasion, débitent des plaques de marbre d’une épaisseur comprise entre 1,5 et 2,5 cm : ce mode d’actionnement fait la spécificité et tout l’intérêt du moulin de Félines. Tout aussi étonnant est le silence des archives qui ne permet aujourd’hui d’avancer aucune datation précise pour cet ensemble dont les auteurs signalent l’état de ruine en 1892 ; seuls des indices d’ordre toponymique trahissent sinon une construction, du moins une utilisation du moulin au milieu du xixe siècle.