bluuebunny/crossref_metadata_2025 huggingface dataset:
General phenolic characterisation, individual anthocyanin and antioxidant capacity of matured red wines from two Portuguese Appellations of Origins
Authors: Cristino Rosa , Costa Elisa , Cosme Fernanda , Jordão António M
Published: January 2013

BACKGROUND

The main aim of this work was to evaluate the general phenolic composition, individual anthocyanin content and total antioxidant capacity from 20 commercial matured red wine samples (vintage from 2005 to 2008) produced in two Appellations of Origin from the north of Portugal: Douro and Dão.

RESULTS

The results showed that the levels of general phenolic compounds, individual anthocyanins and antioxidant capacity in the 20 matured red wine samples analysed differed significantly. In addition, matured red wine samples aged in oak wood had a lower total individual anthocyanin content (from 13.85 to 56.79 mg L−1, averaging 46.13 mg L−1) than wines aged in bottle (from 25.93 to 252.82 mg L−1, averaging 94.17 mg L−1). The total antioxidant capacity values of the analysed wines showed quantitative differences among the values obtained from each antioxidant method applied as well as differences in the range of variation, especially for the values obtained by the DPPH method.

CONCLUSION

The wines used in this study constitute quite a heterogeneous group, made from different Portuguese red grape varieties, with diverse ages and two ageing processes (bottle and oak wood barrels); and accordingly, they showed important differences, especially in their phenolic composition. Finally, the oak wood ageing process before bottling had a negative effect in individual anthocyanins content in contrast to matured red wines submitted only to a bottle ageing process. © 2013 Society of Chemical Industry
Assessment of the impact of the addition of antimicrobial plant extracts to wine: Volatile and phenolic composition
Authors: García‐Ruiz Almudena , Rodríguez‐Bencomo Juan José , Garrido Ignacio , Martín‐Álvarez Pedro J , Moreno‐Arribas M Victoria , Bartolomé Begoña
Published: January 2013

Background

Antimicrobial plant phenolic‐rich extracts have been proposed as alternative to sulfites in the control of the malolactic fermentation (MLF) during winemaking. This addition may affect wine organoleptic properties. In this paper, we have investigated the changes in wine volatile and phenolic composition, after MLF, of a red wine treated with antimicrobial extracts from eucalyptus leaves and almond skins.

Results

Although addition of both extracts led to statistically significant changes (P < 0.05) in the concentration of several esters, alcohols, C13 nor‐isoprenoids and volatile phenols, only few of these volatile compounds showed values of odour activity > 1 aroma unit; that is to say, whose concentrations were higher than their corresponding odour thresholds. With regard to phenolic compounds, the addition of both extracts did not significantly modify the content of anthocyanins, which predicts minor changes in wine colour. However, the content of non‐anthocyanin phenolics was significantly higher in the wines treated with antimicrobial extracts, especially for flavonols, being the dose‐over‐taste factor for these wines significantly higher. Finally, principal component analysis showed that wines were mainly differentiated on the basis of whether MLF was conducted or not, and its method of performance (inoculated/spontaneous).

Conclusion

Addition of antimicrobial extracts leads to some compositional changes in the wine, whose relevance needs to be addressed in future experiments, including wine sensorial analysis. © 2013 Society of Chemical Industry
Sub‐wavelength interference pattern from volume plasmon polaritons in a hyperbolic medium
Authors: Ishii Satoshi , Kildishev Alexander V. , Narimanov Evgenii , Shalaev Vladimir M. , Drachev Vladimir P.
Published: January 2013

Inside of a hyperbolic medium, the principal components of the permittivity tensor have opposite signs causing the medium to exhibit a ‘metallicbr’ type of response to light wave sin one direction, and a ‘dielectric’ response in the other. Our study shows that inside hyperbolic media, volume plasmon polaritons (VPPs) propagate along the characteristic planes, forming distinct, directionally dependent optical responses. This is similar to the propagation of conventional surface plasmon polaritons (SPPs) along the planar interfaces separating the isotropic dielectrics and metallic slabs. Interestingly, the plasmon polariton propagates along the resonance cone in a volume of hyperbolic metamaterial crossing the interfaces of the constitutive materials. The Young's double‐slit scheme is used to study the spatially‐confined diffraction in a hyperbolic slab, made of many thin planar layers of a metal and dielectric, to obtain the sub‐wavelength interference pattern at the output interface. Proof‐of‐concept systems for producing such patterns applicable to nanolithography and subwavelength probes are demonstrated.
A Density Functional Theory Study of Secondary Reactions in n‐Butyl Acrylate Free Radical Polymerization
Authors: Cuccato Danilo , Mavroudakis Evangelos , Dossi Marco , Moscatelli Davide
Published: January 2013

In this work, secondary reactions involved in the free radical polymerization of butyl acrylate are investigated using quantum chemistry. First, various backbiting reactions are studied by adopting a simplified molecular model suitable for treating long polymer chains. The predicted reaction kinetics suggest the possibility of a radical migration along the poly(butyl acrylate) (PBA) chain as a consequence of subsequent j:j + 4 hydrogen abstractions, which are characterized by a low activation energy. Moreover, branching propagation and β‐scission reactions originating from mid‐chain radicals are investigated using a complete PBA model composed of five monomer units. The reaction kinetics involving short‐branch radicals are also examined, and a novel backbiting step leading to the formation of short branches is proposed.

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Applying human computation mechanisms to information retrieval
Authors: Harris Christopher G. , Srinivasan Padmini
Published: January 2013

Crowdsourcing and Games with a Purpose (GWAP) have each received considerable attention in recent years. These two human computation mechanisms assist with tasks that cannot be solved by computers alone. Despite this increased attention, much of this transformation has been limited to a few aspects of Information Retrieval (IR). In this paper, we examine these two mechanisms' applicability to IR. Using an IR model, we apply criteria to determine the suitability of these crowdsourcing and GWAP mechanisms to each step of the model. Our analysis illustrates that these mechanisms can apply to several of these steps with good returns.
Information seeking through microblog questions: The impact of social capital and relationships
Authors: Zhang Pengyi
Published: January 2013

This paper investigates how users of Sina Weibo, a popular microblogging service in China, request information by posting questions to their online social networks. The fast development of social networks and social media such as microblogging sites has greatly impacted how people access and share information. Previous research has focused on how users share information on microblogging sites, but relatively less is known about how users use such networks to seek information. This paper addresses the gap. The data set contains 1969 question messages from 1939 users (information seekers) and 7997 responses to these questions from 3296 users (information providers), the profiles of the information seekers and providers, and their immediate social network (followings and followers). This paper examined the social capital and demographic characteristics of the information seekers, and the relationships between the information seekers and providers with regards to response rates and number of responses as indicators for information and social benefits of information seeking. Results show that 1) questions posted by female users and verified users and messages using the “@” sign have higher response rates; 2) about 70%‐80% of information seeker‐provider pairs are physically close and have reciprocal relationships. The study demonstrates the impact of the information seekers' social capital and their relationships with the information providers in regards to the outcomes of information seeking in Weibo social networks.
Learning to discover: Youth information literacy in the “i” digital age
Authors: Bilal Dania , Erdelez Sanda , Beheshti Jamshid , Todd Ross J.
Published: January 2013

Today's digital information environment is rich with varied types of information that is available anytime, anywhere at a user's fingertips. While children and young adults constitute a high percent of the online population worldwide and are being characterized as “savvy,” or “born digital,” there is a need to examine how what has been considered a “distraction” in using the web can be transformed into valuable information that these young users are enable to capture and use at a later time. Existing models of information behavior in traditional environments may allow us to predict certain aspects of young users' information seeking. However, most of these models do not account for information discovery or information encountering that occurs throughout the information seeking process. In this panel, researchers will discuss the changing nature of teaching, learning, and capturing young users' information behaviors in the “I” digital environment. They will propose ways for developing holistic understanding of young users' information behavior processes that encapsulate information discovery and digital inquiry.
Least information document representation for automated text classification
Authors: Ke Weimao
Published: January 2013

We propose the Least Information theory (LIT) to quantify meaning of information in probability distributions and derive a new document representation model for text classification. By extending Shannon entropy to accommodate a non‐linear relation between information and uncertainty, LIT offers an information‐centric approach to weight terms based on probability distributions in documents vs. in the collection. We develop two term weight quantities in the document classification context: 1) LI Binary (LIB) which quantifies (least) information due to the observation of a term's (binary) occurrence in a document; and 2) LI Frequency (LIF) which measures information for the observation of a randomly picked term from the document. Both quantities are computed given term distributions in the document collection as prior knowledge and can be used separately or combined to represent documents for text classification. We conduct classification experiments on three benchmark collections, in which the proposed methods show strong performances compared to classic TF*IDF. Particularly, the LIB*LIF weighting scheme, which combines LIB and LIF, outperforms TF*IDF in several experimental settings. Despite its similarity to TF*IDF, the formulation of LIB*LIF is very different and offers a new way of thinking for modeling information processes beyond classification.
Searching vs. writing: Factors affecting information use task performance
Authors: Liu Jingjing , Belkin Nicholas J.
Published: January 2013

Searching for information is often driven by some work tasks that involve information use and require certain types of outcomes other than finding information. To explore how search systems can help with work tasks calls for examining factors that influence work task performance. A 3‐stage controlled lab experiment was conducted with 24 participants, each coming 3 times to work on 3 sub‐tasks of a general task, couched either as “parallel” or “dependent” task type. The full task was to write a report on the general topic, with interim documents produced for each sub‐task. Results show that task type and task session did not affect users' task performance, but users' topic familiarity and task experience did. Users' effectiveness in finding useful pages and their time allocated to writing correlated with task performance, so did their reflected perceptions of task experience. Further, users' topic familiarity could lead to a higher writing efficiency, and task experience could lead to higher searching efficiency and effectiveness. These findings help understand factors affecting information use task performance, and have implications on search system design to support information related work task accomplishment.
Analysis of government environmental agency web pages for Colony Collapse Disorder information
Authors: Boehm Meredith K. , Singh Vandana
Published: January 2013

This paper presents the results from a study identifying government entities that provide information about Colony Collapse Disorder (CCD) in order to discover what information is available from the entities' web pages and evaluate the quality of the information provided as it pertains to a defined spectrum of citizen information seekers. Using a government information valuation framework that takes into account these citizen user needs, this paper looks at the information content within the context of the public sphere and applies the lens of post‐normal science theory to analyze the current status of information from these entities. Overall the research shows that citizen user groups are in need of public engagement applications to facilitate a two‐way flow of information.
Information, interaction and innovation in consumer health: New directions at the intersection of information science and informatics: Interaction track ∼ sponsored by SIG‐HEALTH
Authors: Veinot Tiffany , Souden Maria
Published: January 2013

Longstanding approaches to health and health care are failing us: costs have skyrocketed while care quality remains highly uneven; the majority of health care in North America takes place in homes and communities rather than hospitals and doctor's offices; and institutionalized health care often does little to support people psychosocially or prevent people from becoming ill in the first place. Enthusiasm for the potential of consumer participation in health and health care has found advocates among health systems and insurers keen to reduce costs and patient organizations agitating for improved recognition and care. Alongside these trends, we find an increased focus on consumer health in the disciplines of information science and informatics. Health information science studies examine information behavior, information policy, terminology and information retrieval systems. Health informaticians focus on the design and evaluation of consumer‐facing technologies such as personal health records and health behavior tracking systems. Scholars in both fields pursue research concerning social media, including online patient communities. However, despite the growing momentum of scholarly activity in both fields, as well as their topical overlap, the fields remain largely separate, with differing research traditions and scholarly communities. In this panel, we find synergy and common ground between the two fields through an exploration of the conference themes of information, interaction and innovation. In a lightning talk format, eight panelists representing diverse research areas will share their perspectives upon key insights that each field can bring to the other. Building on the arguments presented, panelists and the audience will reflect on the state of consumer health research, and brainstorm regarding future scholarly directions that will leverage the strengths of both fields.
New directions for 21st Century digital collections
Authors: Abreu Amelia , Acker Amelia , Hank Carolyn
Published: January 2013

Across disciplines, new types of digital collections are changing the way we access and preserve information. While scholars, data curators, librarians, archivists, and preservationists all approach digital collections in their work, key questions remain as to how to conceptualize and collaborate in our efforts. This event gathers scholars and practitioners from libraries, archives, data curation and digital humanities to discuss the challenges of 21st Century digital collections.
Humanistic information science
Authors: Feinberg Melanie , Jens‐Erik Mai , Jonathan Furner , Tennis Joseph
Published: January 2013

The panel presents approaches to information science that are grounded in humanities, and argues that the field could be richer if it embraces humanistic approaches to information science. While the field has broadened and changed significantly since ASIST was founded 75 years ago, it is suggested that information science continues to be committed to objectivistic understandings of what is most properly involved in social scientific inquiry. The panelists will present understandings of information science as the field concerned with the fundamental relation between people and reality, and with the culturally‐specific roles that information plays in the practices that constitute this relation. The panelists will present a range of scholarly research topics in humanistic information science that will be used as the springboard for interactions with the audience about the future of a humanistic information science.
The origins of SIG‐III and its 30 years' journey: Visions and reflections
Authors: Alemneh Daniel Gelaw , Carbo Toni , Caidi Nadia , Gruzd Anatoliy , Rorissa Abebe
Published: January 2013

In this panel we will discuss the origins of the Special Interest Group for International Information Issues (SIG‐III) of the American Society for Information Science & Technology (ASIS&T) and its early years. In addition to the reflections of the last 30 years, Toni Carbo (one of the co‐founders of SIG‐III), Nadia Caidi (SIG‐III Advisory board member), Anatoliy Gruzd (Social Media Administrator), Daniel Alemneh (SIG‐III Chair), and Abebe Rorissa (SIG‐III Chair‐elect) look forward and discuss the future of the SIG‐III including strategies to facilitate collaborations and information exchanges globally.
Emerging trends in metadata research
Authors: Moulaison Heather Lea , Rathbun‐Grubb Susan , Abbas June , Greenberg Jane , La Barre Kathryn , Rodríguez Eva Méndez , Mitchell Erik , Šauper Alenka
Published: January 2013

Metadata can be used in a variety of environments, from library catalogs and research databases to data archives, proprietary knowledge bases, and the open web. Multiple sources for metadata creation exist, with metadata being generated by professionals, through automated techniques, and by the public at large. Information professionals are eager to share and leverage data sources to create new knowledge and feed the demand for new interoperable applications. There is great potential for improving discovery by weaving together traditional library metadata with social cataloging metadata to create a new scheme for representing information in library catalogs, institutional repositories, or digital libraries. Each of the researchers on this panel represents a unique perspective on the ways in which metadata research is unfolding and will continue to progress over the next few years. Drs. Erik Mitchell, Jane Greenberg, Eva Méndez Rodríguez, June Abbas, Alenka Šauperl, and Kathryn La Barre will discuss their current research streams, speaking to the above issues via an exemplary project they have chosen to describe. Interactivity between the panelists and among the audience members will be encouraged after the panelists have presented their projects for discussion.
Social curation on the website Pinterest.com
Authors: Hall Catherine , Zarro Michael
Published: January 2013

In this paper we look at the popular social curation website, Pinterest.com and describe some of the user actions taking place within the context of the site. Using Pinterest's API we collected a dataset of over 290,000 pins (images and corresponding metadata) during a month‐long period between February and March 2012. From this dataset, a random sample of 1000 pins was selected for analysis. We found that Pinterest users pin content in a wide variety of subject areas with the most frequently observed categories being Food & Drink, Home & Garden Décor and Design, and Apparel & Accessories. Turning towards source type, we found that pins are most likely to come from blogs, which account for 45% of our sample pins.

Pinterest users can ‘like’, ‘repin’ and comment on the content pinned by others. Repinning, in which a user can categorize an image onto one of their own boards, is the most frequently observed behavior. User comments, which have been observed in the literature to offer valuable sources of potential metadata, are plentiful on Pinterest. We collected 510 user comments from a random sample of 40 pins and found that four of the six types of comments described by van Hooland, Rodriguez and Boydens (2011) were present in our sample: sharing opinion & judgment, engaging in dialog, sharing a personal history with the image, and providing additional narrative details. We suggest that Pinterest represents a sharing and curating experience that offers insight into information use, reuse and creation on the social web.
The effect of task roles on the perceived usability of management tools
Authors: Xiao Lu , Quan‐Haase Anabel
Published: January 2013

We investigate how demands of a task create differing task roles with distinct levels of information uncertainty, information and cognitive load, and social responsibility. Pairs solved a standard matching game using tangrams under three different instant messaging (IM) tool conditions. We show that a participant's use and evaluation of the IM tool are largely based on their assigned task roles. The findings inform the testing and evaluation of future collaborative systems and visualization tools by demonstrating the relevance of task roles in the use and utility of these systems and tools.
Geovisualization of bibliographic data using ArcGIS
Authors: Hubbard David E. , Drews Patricia L.
Published: January 2013

This study examined the geographic aspects of literature involving the visualization of bibliographic data published by authors residing in the contiguous United States. ArcGIS was used to visualize networks of cited‐citing publications and co‐authors for 102 publications based on first author institutional affiliation. Spatial statistics and other tools within ArcGIS were used to explore the clustering of research activity and test the “death of distance” hypothesis among co‐authors. Both the “producers” and “consumers” of the scholarly output were found to be clustered. Visual inspection of the thematic maps found research activity concentrated in the following cities: Bloomington, IN, Philadelphia, PA, Sandia, NM, Stillwater, OK, and Tucson, AZ. Over half of the co‐authorship (60%) occurred among authors within the same ZIP code. The cited‐citing publication network and co‐author network maps shared a characteristic pattern indicating that many producers and consumers also co‐authored with each other. While the number of co‐authored publications in the field of visualization of bibliographic data increased from 1995–2009, the average co‐author distance remained unchanged over that period.
Identifying factors of online news comments
Authors: Chen Hsin‐liang
Published: January 2013

The purpose of this project was to identify the factors which should be studied based on the available components of the online comments and using available data analysis tools. The factors were the geographic locations, the number of readers' recommendations as a sentimental indicator, and top phrases of the comments. The selected news story was the execution of Troy Davis reported by The New York Times on September 21, 2011 (Severson, 2011). Troy Davis, an African American, was convicted of murdering an off‐duty police officer in Savannah, Georgia in 1989. The U.S. Supreme Court rejected the appeal despite worldwide opposition to Davis's death sentence. This story was selected due to the significant international level of attention it received, and the topic of “death penalty.” There were 1527 comments collected on December 22, 2011, 60 days after the story was published online. The comments were classified into 2‐tier geographic categories based on the 4 regions and 9 divisions defined by the U.S. Census Bureau. The preliminary results indicated that the geographic locations, the number of readers' recommendations as a sentimental indicator, and top phrases of the comments were appropriate research factors for studying online news comments.
Monitoring knowledge flow through scholarly networks
Authors: Yan Erjia , Ding Ying , Kong Xiangnan
Published: January 2013

The production and creation of knowledge is not dependent on any individual and isolated entity; instead, knowledge is diffused, exchanged, and circulated among various entities. To study the knowledge flow and transfer within and across different disciplines can help us better understand science and scientific collaboration. This paper presents a methodological framework to study knowledge flow, including a knowledge hierarchy, the construction of knowledge flow network, and indicators that can be used to measure disciplinarities.
Information curation
Authors: Jacobson Jenna
Published: January 2013

Various information models have been developed to explain information practice; however, this poster suggests the changes brought about by social bookmarking in a Web 2.0 environment require a new type of information practice, which I call information curation. Information curation describes an alternative type of information practice to account for the social networking, identity construction, and creative expression of the information curator.
License analysis on e‐journal perpetual access of library
Authors: Zhang Mei , Eschenfelder Kristin
Published: January 2013

This poster presents preliminary findings of a content analysis of 72 e‐journal licenses in terms of perpetual access clauses. This study explored whether perpetual access clauses varied among commercial publishers, society publishers and university presses, whether clauses changed over time, and whether differences existed between consortia and site licenses. Findings showed that the licenses from commercial publisher were more likely to provide perpetual access than licenses from other two types of publishers. We observed an increasing trend in providing perpetual access over time. Consortia licenses were more likely to depend on third‐party to obtain perpetual access than site licenses. This study can be helpful for libraries to understand the institutionalization of perpetual access clause in e‐journal licenses.
Enhancing cultural heritage collections by supporting and analyzing participation in Flickr
Authors: Jett Jacob , Senseney Megan , Palmer Carole L.
Published: January 2013

Cultural heritage institutions can enhance their collections by sharing content through popular web services. Drawing on current analyses from the Flickr Feasibility Study, we report on the pronounced increase in use of the IMLS DCC Flickr Photostream in the past year, trends in how users are engaging with the content, and data provider perspectives on participation in Flickr through the DCC. In addition to users providing comments and tags for images, they are increasingly integrating historical images from libraries and museums into new digital objects and special collections. Intermediary services can fill a key role in lowering the burden for institutions to engage in Web 2.0 initiatives and broadening public access to cultural heritage content. To extend the scope of the current DCC services, we propose a feedback framework for transferring user‐generated information to institutional data providers.
Visualizing linked Jazz: A web‐based tool for social network analysis and exploration
Authors: Miller Matthew , Walloch Jeff , Pattuelli M. Cristina
Published: January 2013

This paper intends to demonstrate that recent improvements in web‐based technology have made the creation of web‐based network visualizations a viable and appealing possibility. We showcase a network visualization tool made for the Linked Jazz Project which utilizes a number of interactive and multimedia features to deliver an engaging experience to a wide audience. We briefly explore the history, benefits, and possible limitations of this web‐based approach.
Developing a typology of online Q&A models and recommending the right model for each question type
Authors: Choi Erik , Kitzie Vanessa , Shah Chirag
Published: January 2013

Although online Q&A services have increased in popularity, the field lacks a comprehensive typology to classify different kinds of services into model types. This poster categorizes online Q&A services into four model types – community‐based, collaborative, expert‐based, and social. Drawing such a distinction between online Q&A models provides an overview for how these different types of online Q&A models differ from each other and suggests implications for mitigating weaknesses and bolstering strengths of each model based on the types of questions that are addressed within each. To demonstrate differences among these models an appropriate service was selected for each of them. Then, 500 questions were collected and analyzed for each of these services to classify question types into four categories – information‐seeking, advice‐seeking, opinion‐seeking, and non‐information seeking. The findings suggest that information‐seeking questions appear to be more suitable in either a collaborative Q&A environment or an expert‐based Q&A environment, while opinion‐seeking questions are more common in community‐based Q&A. Social Q&A, on the other hand, provides an active forum for either seeking personal advice or seeking non‐information related to either self‐expression or self‐promotion.
Using data profiles to select digital asset management systems (DAMS)
Authors: Zilinski Lisa D. , Lorenz Sonia W.
Published: January 2013

Many grants, including grants from the National Science Foundation (NSF) require recipients to utilize data management plans; some grants, like those given by NSF, require recipients to place their data in searchable data repositories. It is difficult to find one data repository that meets every researcher's needs. To solve this problem, we utilized Purdue's Data Curation Profile Toolkit to interview researchers at our university and assist in developing data profiles/plans. These profiles provided the Digital Asset Management (DAM) project team with valuable information about the researchers' data needs. The DAM project team created a matrix of the researchers' data needs and used the matrix to evaluate the credentials of 24 Digital Asset Management Systems (DAMS). The team was able to select the DAMS that met the needs of researchers. Using this method, any university could select a DAMS and be confident that it would meet the needs of the researchers it was intended to serve.
Identifier schemas and research data
Authors: Lee Dong Joon , Stvilia Besiki
Published: January 2013

This work‐in‐progress paper presents the methodology and preliminary results of a study that develops a model for identifier schema evaluation and examines identifier schemas currently used for data referencing in the institutional digital repositories of the members of the Association of American Universities. The study's findings can inform librarians, repository managers, scholarly communities, and publishers about the needs and requirements for an identifier schema to help discover, aggregate, and cite data as well as the issues and problems related to current uses of identifier schemas for data.
Curation roles and perceived priorities for data quality dimensions and skills in genome curation work
Authors: Huang Hong , Stvilia Besiki , Jörgensen Corinne
Published: January 2013

Genome curation work included users with different curation roles as end‐users, curators and dual‐role users. Genomics scientists with certain role might focus on different data quality aspects and skills requirements. There is a lack of understanding of scientists' perceptions and requirements which hampers the development of systematic and tailed approaches to genome data curation. This research surveyed 158 genomics scientists on their perception and priorities for data quality dimensions and quality sills. The study's findings show that depending on the roles played in scientific data sharing and curation process, genome scientists may have different priorities for and ways of assessing data quality. Curators valued higher the direct quality assessment criteria, while end‐users preferred the quality criteria that could be assessed indirectly. Likewise, end‐users assigned higher priorities to the data quality assessment skills and the skills needed to identify useful information, while curators valued higher the skills needed to make data useful.
Readability applications: Improving reading in a world of information overload
Authors: Richardson Ben , Lowrance Nathan
Published: January 2013

This poster discusses the findings of two focus groups that explored the benefits of an innovative readability application (Safari Reader). This emerging technology allows for the removal of advertising and other peripherals from around the body of the online text, thus presenting online articles in a more readable format. The focus group discussions were centered on exploratory research questions that examined information seeking habits for online news content, online information sharing, the ease of reading an online article in its entirety, and the benefits and drawbacks of using a readability application. The poster will show how the questions prompted answers about how the readability technology affected information seeking behavior, information sharing, human computer interaction, advertising and visualization. The poster will highlight the focus group's findings and the possibilities for future research on this type of technology. Additionally, we will utilize and incorporate a tablet (iPad2) into the poster to provide an interactive experience that will showcase the technology in question.
The data‐at‐risk initiative: Analyzing the current state of endangered scientific data
Authors: Murillo Angela P. , Thompson Cheryl A. , Carver Nico , Robertson W. Davenport , Greenberg Jane , Anderson William L.
Published: January 2013

Examining fragile scientific data is crucial to ensuring that these data are not lost and can continue to be part of the scientific process. In order to investigate various aspects of endangered scientific data the Data‐At‐Risk Initiative (DARI) project has conducted three studies that provide insight into the current state of scientific data‐at‐risk. The three projects include (1) a metadata/system review of the of the to the Data‐At‐Risk Inventory, (2) focus groups with fourteen scientific scholars, and (3) surveys completed by 43 information custodians. This poster reports results from these studies, specifically how scientific scholars and information custodians view endangered data. The DARI project aims to understand the current state of endangered scientific data and to assist in the reduction of loss of valuable scientific data.
Exploring and describing search expertise
Authors: Smith Catherine L.
Published: January 2013

We present work in progress on an exploratory longitudinal study of the search behavior of students as they worked on assignments for a semester‐long course on expert search. Our goals were to observe students as they acquired search skills, and to describe behavior associated with the skills learned. Nine MLIS graduate students completed the remote study, providing detailed logs of searches conducted during coursework. In this poster, we focus on assignments completed using Dialog Classic. We briefly review motivations for the study, related work, and our method. We then discuss our analysis approach, and conclude with an example from our data.
Empowering digital libraries users through combining taxonomies with folksonomies
Authors: Alemneh Daniel Gelaw , Rorissa Abebe
Published: January 2013

The increase in the number and heterogeneity of digital resources has led cultural heritage institutions to develop tools, workflows, and quality assurance mechanisms that allow effective digital resource management. This poster assesses the current landscape in digital libraries as well as best practices and identifies emerging trends in information indexing. It also explores the potentials of and controversies surrounding user supplied tags or keywords in terms of complementing established controlled vocabularies in a diverse and collaborative environment.
Nuclear magnetic resonance imaging of tumour growth and neovasculature performance in vivo reveals Grb7 as a novel antiangiogenic target
Authors: García‐Palmero Irene , López‐Larrubia Pilar , Cerdán Sebastián , Villalobo Antonio
Published: January 2013

Development of neovasculature is a necessary requirement for tumour growth and it provides additional opportunities for therapeutic intervention. However, current antiangiogenic therapies have limited efficacy, mostly because of the development of resistance. Hence, characterization of new antiangiogenic molecular targets is of considerable clinical interest. We report that a calmodulin‐binding domain (CaM‐BD) deletion mutant of the growth factor receptor bound protein 7 (Grb7) (denoted Grb7Δ) impairs tumour growth and associated angiogenesis in vivo. We implanted glioma C6 cells in rat brains transfected with an enhanced yellow fluorescent protein (EYFP) chimera of Grb7∆, its EYFP‐Grb7 wild type counterpart, and EYFP alone. We systematically followed intracerebral growth of the tumours, their cellularity and the functional performance of tumour‐associated microvasculature using magnetic resonance imaging, including anatomical T1W and T2W images and functional diffusion and perfusion parameters. Tumours grown from implanted C6 cells expressing EYFP‐Grb7Δ developed slower, became smaller and presented lower apparent cellularity than those derived from cells expressing EYFP‐Grb7 and EYFP. Vascular perfusion measurements within tumours derived from EYFP‐Grb7∆‐expressing cells showed significantly lower cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) values. These findings were independently validated by histological and immunohistochemical techniques. Taken together, these findings confirm that the CaM‐BD of Grb7 plays an important role in tumour growth and associated angiogenesis in vivo, thus identifying this region of the protein as a novel target for antiangiogenic treatment. Copyright © 2013 John Wiley & Sons, Ltd.
Heterojunction based hybrid silicon nanowire solar cell: surface termination, photoelectron and photoemission spectroscopy study
Authors: Bashouti Muhammad Y. , Pietsch Matthias , Brönstrup Gerald , Sivakov Vladimir , Ristein Jürgen , Christiansen Silke
Published: January 2013

Silicon nanowires (SiNWs) combined with a conducting polymer are studied to constitute a hybrid organic/inorganic solar cell. This type of cell shows a particularly high interfacial area between SiNWs and the polymer so that interfacial control and interface optimization are required. For that purpose, we terminated the SiNW surfaces with well selected functional groups (molecules) such as native oxide (hereinafter SiO2‐SiNW), hydrogen (hereinafter H‐SiNW) and methyl (hereinafter CH3‐SiNW). A radial hetero‐junction solar cell is formed, and the cell parameters with and without interface control by functionalization with molecules are compared. Electronically, the three surfaces were close to flat‐band conditions. The CH3‐SiNW, H‐SiNW and SiO2‐SiNW produced a surface dipole of −0.12, +0.07 and 0.2 eV and band bending of 50, 100 and 170 meV, respectively. The surface properties of functionalized SiNWs are investigated by photoelectron yield (PY) and photoemission spectroscopy. PY studies on functionalized SiNWs are presented for the first time, and our results show that this type of measurement is an excellent option to carry out interface optimization of NWs for envisaged nano‐electronic and photonic applications. The solar cell efficiency is increased dramatically after terminating the surface with CH3 molecules due to the decrease of the defect emission. The differently functionalized SiNW surfaces showed identical absorbance, reflectance and transmission so that a change in PY can be attributed to the Si–C bonds at the surface. This finding permits the design of new solar cell concepts. Copyright © 2013 John Wiley & Sons, Ltd.
Confinement mechanism of electrospun polymer nanofiber reinforcement
Authors: Arinstein Arkadii
Published: January 2013

The sharp increase in elastic modulus of electrospun polymer nanofibers with decrease in their diameters is now a well‐known phenomenon. Unfortunately, up to now, the physical reasons resulting in the above size‐dependent behavior are unclear. The proposed explanation is based on the confinement concept. A manifesting mechanism of the confinement effect which provides the size‐dependent elastic modulus of electrospun polymer nanofibers is discussed. According to this model, the nanofiber polymer matrix contains anisotropic regions consisting of correlated worm‐like subchains, partially oriented along the fiber. A fiber elongation is accompanied by relative rotations of the above regions. Confinement effect is that these rotations are hindered by the fiber boundary. As a result, the elastic modulus depends on the fiber diameter. This restriction is dominant for the thin fibers, is decreasing with increase of the fiber diameter, and becomes negligible for thick fibers. Such a behavior is in good agreement with experimental observations. © 2013 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013
Mechanistic model for deformation of polymer nanocomposite melts under large amplitude shear
Authors: Senses Erkan , Akcora Pinar
Published: January 2013

We report the mechanical response of a model nanocomposite system of poly(styrene) (PS)‐silica to large‐amplitude oscillatory shear deformations. Nonlinear behavior of PS nanocomposites is discussed with the changes in particle dispersion upon deformation to provide a complete physical picture of their mechanical properties. The elastic stresses for the particle and polymer are resolved by decomposing the total stress into its purely elastic and viscous components for composites at different strain levels within a cycle of deformation. We propose a mechanistic model which captures the deformation of particles and polymer networks at small and large strains, respectively. We show, for the first time, that chain stretching in a polymer nanocomposite obtained in large amplitude oscillatory deformation is in good agreement with the nonlinear chain deformation theory of polymeric networks. © 2013 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013
Effect of annealing and nitridation on (0001) sapphire surface polaritons
Authors: Zhuravlev Konstantin , Malin Timur , Mansurov Vladimir , Novikova Nadezhda , Yakovlev Vladimir
Published: January 2013

The effect of annealing temperature on nitridation process of (0001) Al2O3 surface under ammonia flux was investigated by high‐energy electron diffraction and surface polaritons spectroscopy. High temperature annealing (≥1150 °C) of the surface results in the surface reconstruction √31×√31R±9° that inhibits the nitridation process. The external reflectivity infrared spectroscopy at near normal incidence angle is not sensitive to the annealing and nitridation. On the other hand, the high‐frequency minimum in the attenuated total reflection spectra splits near 700 cm–1 due to the surface reconstruction and/or the presence of aluminum nitride on the substrate surface, the splitting is sensitive to the surface treatment. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Higher than 90% internal quantum efficiency of photoluminescence in GaN:Si,Zn
Authors: Reshchikov M. A. , McNamara J. D. , Behrends A. , Mohajerani M. S. , Bakin A. , Waag A.
Published: January 2013

Photoluminescence (PL) from high‐quality GaN codoped with silicon and zinc was investigated in detail. The internal quantum efficiency (IQE) of PL was determined from the analysis of the dependencies of the PL intensity on the excitation intensity and temperature, and the simulation of these dependencies with a phenomenological model based on rate equations. The model reproduces an important phenomenon: the quenching of a recombination channel with a high IQE causes a rise in efficiency of all the other PL bands. Quantitative analysis of this phenomenon allows one to determine reliably the absolute IQE of PL. The absolute IQE of the PL in GaN co‐doped with Si and Zn exceeds 90%, with the largest contribution coming from the blue luminescence band associated with the ZnGa acceptor. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Properties of MOCVD GaN/AlGaN heterostructures grown on polar and non‐polar bulk GaN substrates
Authors: Rudziński M. , Kudrawiec R. , Kucharski R. , Dwiliński R. , Strupiński W.
Published: January 2013

In this work we present structural, optical and electrical properties of GaN epilayers and AlGaN/GaN MOCVD heterostructures obtained on polar and non‐polar 10x10 mm2, 1 and 1.5 inch bulk ammonothermal GaN substrates. The results were obtained based not only on a single‐point measurement but also on mapping across the sample area. In contactless electroreflectance (CER) spectra CER resonances related to optical transitions between excited states were clearly observed for GaN/AlGaN QWs grown on c ‐plane GaN substrates, whereas such features were not noted in the case of GaN/AlGaN QWs grown on m ‐plane GaN substrates. This experimental result clearly shows that the polarization‐related electric field leads to the quantum confinement of some extra states in the polar QW system. To check the advantage of homo‐epitaxy using ammonothermal GaN, high electron mobility transistors (HEMTs), and light emitting diodes (LEDs) structures were grown on (0001) Ga‐polarity, semi‐insulating and conductive GaN substrates respectively (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Dereferee: instrumenting C++ pointers with meaningful runtime diagnostics
Authors: Allevato Anthony , Edwards Stephen H.
Published: January 2013

Proper memory management and pointer usage often prove to be the most difficult concepts for students learning C++ to grasp. Compounding this problem is the fact that the compilers and runtime environments traditionally used to introduce these concepts leave much to be desired with regard to generating meaningful diagnostics to assist students in tracking down and fixing memory‐related logical errors. To alleviate this, we have developed Dereferee, an advanced yet thin wrapper around C++ pointers that greatly increases the quality of these runtime diagnostics, but with only a small amount of intrusion into the development process. With regard to performance, memory‐intensive programs will experience execution times approximately 20–30 times slower when using Dereferee, which is comparable with other similar tools. Furthermore, the library has been designed to be customizable and easily disabled to transition codes from development to production.Copyright © 2013 John Wiley & Sons, Ltd.