bluuebunny/crossref_metadata_2025 huggingface dataset:
Moving to the Next Level
Authors: Underwood Jody S. , Kruse Stacy , Jakl Peter
Published: May 2010

The educational research community has been experimenting with educational games with a focus on pedagogy and curriculum, but little effort has been made to assess what students are actually learning in these environments. Designing embedded assessments into games is one of the critical gateways to creating learning tools that are maximally engaging for the learner, using sound pedagogical methodology as a foundation. The authors review the research in this area and describe technology that facilitates near real-time data collection through embedded assessments, visual data mining, inference mechanisms, and dynamic individualization. They then describe a methodology for creating valid embedded assessments and identify types of data that can be collected from gaming environments along with approaches for analysis, all toward the goal of individualized adaptation.
Benefits of Video and Eye Toy Gaming for Children with Autism
Authors: Silton Nava , D’Alessandro Ann Higgins
Published: May 2010

The purpose of this chapter is to illustrate how video games, which incorporate eye toy technology, can be utilized to teach social learning to children with autism directly through video modeling and multimedia social story interventions and indirectly through engaging typically developing students with educational video games that increase their sensitivity, knowledge, and behavioral intentions when interacting socially with children on the spectrum and with other disorders, as well. The popular medium of gaming is designed to enhance the appeal of rote instruction for children and their families as well as to create tools that improve a child’s ability to generalize learned social and adaptive skills. Moreover, these tools will offer richer research methodologies for tracking and understanding important micro-developmental changes in daily and weekly interpersonal skills development among both typical and atypical children.
Providing Quality of Service across Multiple Providers
Authors: Bouras Christos , Gkamas Apostolos , Stamos Kostas
Published: May 2010

In this chapter, the authors present some of the latest developments related to the provisioning of Quality of Service (QoS) in today’s networks and the associated network management structures that are or will be deployed to support them. They first give a brief overview of the most important Quality of Service proposals in the areas of Layer 2 (L2) and Layer 3 (L3) QoS provisioning in backbone networks, and they discuss the network management structures and brokers that have been proposed in order to implement these services. As a case study, they describe the pan-european research and academic network, which is supported centrally by GEANT and which encompasses multiple independent NRENs (National Research and Education Networks). In the last few years, GEANT has developed and deployed a number of production and pilot services meant for the delivery of quality network services to the end users across Europe.
Genetic Programming for Cross-Release Fault Count Predictions in Large and Complex Software Projects
Authors: Afzal Wasif , Torkar Richard , Feldt Robert , Gorschek Tony
Published: May 2010

Software fault prediction can play an important role in ensuring software quality through efficient resource allocation. This could, in turn, reduce the potentially high consequential costs due to faults. Predicting faults might be even more important with the emergence of short-timed and multiple software releases aimed at quick delivery of functionality. Previous research in software fault prediction has indicated that there is a need i) to improve the validity of results by having comparisons among number of data sets from a variety of software, ii) to use appropriate model evaluation measures and iii) to use statistical testing procedures. Moreover, cross-release prediction of faults has not yet achieved sufficient attention in the literature. In an attempt to address these concerns, this paper compares the quantitative and qualitative attributes of 7 traditional and machine-learning techniques for modeling the cross-release prediction of fault count data. The comparison is done using extensive data sets gathered from a total of 7 multi-release open-source and industrial software projects. These software projects together have several years of development and are from diverse application areas, ranging from a web browser to a robotic controller software. Our quantitative analysis suggests that genetic programming (GP) tends to have better consistency in terms of goodness of fit and accuracy across majority of data sets. It also has comparatively less model bias. Qualitatively, ease of configuration and complexity are less strong points for GP even though it shows generality and gives transparent models. Artificial neural networks did not perform as well as expected while linear regression gave average predictions in terms of goodness of fit and accuracy. Support vector machine regression and traditional software reliability growth models performed below average on most of the quantitative evaluation criteria while remained on average for most of the qualitative measures.
Computer Courses in Adult Education in a Gender Perspective
Authors: Salminen-Karlsson Minna
Published: May 2010

In this study of computer courses in municipal adult education, 173 questionnaires from 10 Swedish adult education centres with students taking a basic computer education course were analyzed. The main findings were that men consistently reported greater computer competence, while computer interest or computer attitudes did not show gender differences. The gender differences in computer competence were significant even in the youngest age group. Young women were also the most distinctive group by being the most dissatisfied. The idea that gender issues in adult computer education mainly concern computer reticent middle aged women while young women attend computer courses on a more equal footing with men does not hold in this sample. The results raise some practical questions, particularly in assessing the differences in computer competence and women’s feelings of inadequacy, taking advantage of women’s computer interest, and coming into terms with young women’s expectations.
Choosing the Appropriate E-Learning System for a University
Authors: Mahlow Cerstin
Published: May 2010

In this chapter the author discuss the introduction of an e-learning system to enhance teaching and learning at a university. The focus is on the decision process choosing a system. Abstract criteria and feature lists are not sufficient for choosing the right e-learning software, even if all stakeholders and their respective requirements are heard. The author argues that “soft” factors should be considered when evaluating e-learning software: (1) The age of the students and their level of education, (2) the pedagogical guidelines and the culture of teaching and learning of the university, and (3) the educational scenarios in lectures and seminars. These factors seem to be only small details and are typically neither mentioned in the requirements nor in the feature lists of e-learning software. Therefore the author proposes that institutions should evaluate prospective systems in real-world scenarios. As a case in point, the author will outline a number of significant differences between two e-learning systems with a focus on pedagogical aspects. The systems can be seen as representative for a certain class of systems; both offer all features that are commonly seen as the most relevant when making a decision for a university e-learning system.
eUreka
Authors: Tan Daniel T.H. , Lu Adrian D.H. , Wong Sheryl E.
Published: May 2010

Project work is an established learning activity for students. It is a learner effort-based endeavour towards the higher learning objectives or Bloom’s taxonomic outcomes of beyond application into analysis, evaluation and creation. Its many forms include the final year (or capstone) project, term or mini-projects, group project work, field trips and studies, etc. It can include and extends beyond problem-based learning. The nature of such project work might be investigative, analytical, case study, information gathering, research or development. Nanyang Technological University (NTU) has explored an extension of eLearning from a means of knowledge transfer and delivery coupled with pedagogy to that of knowledge creation and discovery. Via eUreka, this web-based project work management system facilitates the constructivist learning approach of students to be more effectively managed, supervised and mentored. Web 2.0 tools such as weblogs facilitates opportunities to participate, deliberate, feedback, comment and collaborate in the process of learner-centric knowledge creation and discovery.
Distance Learning Courses
Authors: Walters Kelley , Shaw Melanie , Long David
Published: May 2010

Drawing on current literature and a survey of online students and instructors from online institutions, the researchers explored the different types of assignments and assessments required for completion of online courses, the Learning Management Systems utilized, and differences between undergraduate and graduate tasks assigned, according to field of study. While there is a significant amount of available research on instructional efficacy in online classes, there are few studies that account for the types of course activities students must complete in distance learning courses. This study details the variety of online assessments and activities assigned to students attending institutions of higher education that are either fully online or utilizing a blended learning format. Recommendations are made for diverse instructional tasks, which can be assigned based on available technology and curricular flexibility. Key terms used in the study are defined at the end of this chapter.
Collaborative Student Groups and Critical Thinking in an Online Basic Communication Course
Authors: Schwartzman Roy , Morrissey Megan
Published: May 2010

This chapter examines discussion board postings of ten undergraduate student groups (n = 45 students) who participated in collaborative problem-solving in a fully online, introductory communication course. Postings during a full academic year—three sections offered during three consecutive 15-week trimesters—reveal that student usage of the online format did not exhibit progressive development of critical thinking. Few student posts exhibited qualities of interrogation, exploration, convergence, or application that constitute the reflective thought process. Instead, students used threaded discussions primarily as forums for personal assertions, relational maintenance, and summaries of research. The study suggests that concepts of critical thinking require adaptation to an online environment that diverges from the linear cognitive process assumed in traditional approaches to critical inquiry. The online learning environment must reconcile the strong need to establish group cohesion with the impetus toward groupthink that limits critical thinking.
"There's Always Hope"
Authors: Ginossar Tamar
Published: May 2010

The Internet has changed the ways in which many people cope with illnesses, by allowing for conversations between similar others that transcend traditional barriers of time and place. Despite the revolutionary potential of Internet support groups, little is known about the ebb and flow of discussion in these groups. This chapter describes online discussion in a Lung Cancer Internet Support Group. Methods include quantitative and qualitative analysis of email messages posted to this group during one month. The results reveal (a) the content of the discussion, (b) participants in the discussion, (c) topics that elicited discussion and (d) themes and messages that were “silenced.” The implications of these findings to patients and their family members, to scholars, and to health practitioners are discussed.
Wikis as Open Educational Resources in Higher Education
Authors: Kehrwald Benjamin , Danaher P. A.
Published: May 2010

Open wikis such as WikiEducator (WE) (http://www.wikieducator.org/Main_Page) lie at the intersection of two significant applications of learning technology: open educational resources (OERs), which are freely available materials that can be shared, modified, adapted, and reused in diverse learning contexts; and collaborative authoring environments. This chapter presents a case study of the use of open wikis in a single online postgraduate course in the College of Education at Massey University (New Zealand). The case discussion includes an illustration of the use of open wiki technology at WikiEducator within the course from two different points of view: the use of wikis as a presentation tool by the course teaching staff; and as a production tool by learners seeking to create OERs as part of an instructional design project. The chapter also links the challenges and opportunities associated with these points of view to wider possibilities and pressures attending the terrain in which contemporary higher education is situated.
Globalization of Instruction
Authors: Holland Janet , Holland Joe
Published: May 2010

The aim of the study was to find ways to embrace the current realities of a global society and use it to build the intellectual capital of students from elementary school through college then into the work environment. This took a concerted effort examining the literature in regards to globalization, the intellectual capital needed for globalized work environments, and the implications for globalized teaching and training for adapting to current economies. This chapter is designed to help you begin your own examination of these issues with an eye toward educational solutions at all levels. A pilot study was conducted of international college students at a small midwestern university, to serve as a model for conducting your own needs analysis. The analysis should help you to begin thinking differently about the educational needs for globalized classrooms and work environments while building the needed intellectual capital to survive and thrive under changing conditions.
Fundamentals of Interprofessional Communication
Authors: Solomon Patricia , Baptiste Sue
Published: May 2010

This chapter presents the development, implementation and evaluation of a module on interprofessional communication skills that incorporates principles of problem-based learning, delivered entirely online. Learners focus initially on foundational concepts of relationship and patient centered care, the importance of self awareness and understanding their own professional values and biases, progressing towards teamworking to develop common patient care goals. The module faculty facilitator is essential to role model and foster interprofessional collaboration. Qualitative content analyses of discussion board postings across 29 students, supplemented by small-scale in-depth interviews and a focus group, reveal they are able to learn interprofessional communication skills online. The 10 students who undertook both module components completed a project evaluation form: there was 85.6% agreement that the module taught them about interprofessional education and 92.9% agreement that their knowledge of other health professionals’ perspectives increased. An online module can support the development of communication skills, but is recommended as one component of an overall interprofessional education curriculum.
Customisation and the Interprofessional Application of E-Learning Objects
Authors: Lynch Helen M. , Trabinger Kerry
Published: May 2010

Toolbox learning objects are a class of pedagogically rich, sophisticated e-learning objects created for the Australian vocational education and training system (VET). Their richness makes them very attractive to teachers and trainers working across a range of learning contexts but at the same time makes them difficult to reuse. While these e-learning objects have been designed to be customised and are often repurposed for use within one vocational context, an approach is emerging that sees them increasingly customised for reuse across a range of intervocational or interprofessional contexts. This chapter describes this approach, focusing on the tools and techniques of customisation, and presents a model of reuse that can be implemented elsewhere with any pedagogically rich web based e-learning object in intervocational and interprofessional settings. Toolbox learning objects are freely available to anyone with internet access from the Toolbox Learning Object Repository website. The Repository is fully searchable and objects can be previewed from the Repository website and downloaded without charge for educational use. This chapter will be of value to teachers, trainers and academics who are exploring the reuse of pedagogically rich web based e-learning resources for interprofessional or intervocational education.
Audio Watermarking
Authors: Drajic Dejan , Cvejic Nedeljko
Published: May 2010

In this chapter, the authors recapitulate the background and the state-of-the-art of digital audio watermarking, including descriptions of audio watermarking algorithms and malicious attacks against these algorithms. The areas in which audio watermarking has been implemented and the possible future applications are outlined. The three requirements of the “magic triangle” in audio watermarking are described as well, with characterized by a number of defining properties, including robustness, watermark bit rate and perceptual transparency. The chapter also provides a comprehensive list of attacks used by adversaries to interfere with the embedded watermark and to prevent its detection.
Spread Spectrum Watermarking
Authors: Maity Santi P.
Published: May 2010

Spread spectrum (SS) watermarking has proven to be efficient, robust and cryptographically secure. Each bit of watermark information is embedded over wide spectrum of the host signal based on spectrum spreading concept of SS modulation in digital communication and can easily be integrated with many existing data transmission scheme. This has made SS watermarking method more attractive during recent times for many non-conventional applications such as broadcast monitoring, security in communication, authentication and blind assessment of quality of services (QoS) for multimedia signals in mobile radio network. These applications essentially demand development of low cost algorithms so that they can be implemented on real time system through hardware realization. Hardware realization offers advantages over software realization in terms of less area, low execution time, low power, real-time performance, high reliability and also ease of integration with existing consumer electronics devices. This chapter first presents a brief review on hardware implementation of digital watermarking algorithms, followed by development of hardware architecture for spatial domain and fast Walsh transform (FWT) domain SS watermark system design using field programmable gate array (FPGA). A brief sketch on hardware implementation for biorthogonal wavelet based Hilbert transform is also shown that may be extended to design SS watermarking based on the concept of two previous architectures. Few challenges for hardware design of watermarking algorithms are then mentioned with an objective to give an idea how to develop watermarking algorithms so that it can be implemented on hardware. The chapter ends with few open research problems on hardware architecture as scope of future research work.
More Survival Data Mining of Multiple Time of Endpoints
Authors: Cerrito Patricia , Cerrito John
Published: May 2010

Survival analysis is almost always reserved for an endpoint of mortality or recurrence. (Mantel, 1966) However, it can be used for many different types of endpoints as the survival distribution is defined as the time to an event. That event can be any endpoint of interest. For patients with chronic diseases, there are many endpoints to examine. For example, patients with diabetes want to avoid organ failure as well as death, and treatments that can prolong the time to organ failure will be beneficial. For patients with resistant infections, treatments that prevent one or multiple recurrences should be explored. Survival data mining differs from survival analysis in that multiple patient events can occur in sequence. The first step in survival data mining is to define an episode of treatment so that the patient events can be found for analysis. It can be thought of as a sequence of survival functions. In this chapter, we will look at the time to a switch in medications, and contrast how prescriptions are given to patients, either following or disregarding treatment guidelines.
Does Computer Game Experience Influence Visual Scenario Assessment of Urban Recreational Paths?
Authors: Arnberger Arne , Reichhart Thomas
Published: May 2010

During the past decades, computer visualizations have been frequently used in urban e-Planning and research. The question arises of whether the degree of experience with the computer during leisure time can have an influence on the assessment of computer-visualized outdoor environment scenarios using visualizations comparable to computer games. We used a computer-animated choice model to investigate the influence of computer game experience on respondents’ preferences for an urban recreational trail. Static and animated representations of use scenarios were produced with 3-D computer animation techniques. Three social factors were investigated: number of trail users, user composition, and direction of movement: The scenarios were presented to respondents (N = 149), segmented into groups with different computer game experience. The results indicate that the individual experience with computer gaming and the presentation mode influences the evaluation of trail scenarios. Animated trail scenarios seem to be more useful than static ones.
Effectiveness of E-government in Delivering Services
Authors: Park Ronnie
Published: May 2010

This chapter examines the effectiveness of delivering e-government services in terms of how citizens value the service and how e-government has changed citizens’ expectation of contacting government by digital means. This chapter articulates the following issues as they are related to the effectiveness of e-government services. It starts by addressing e-government strategies in developing and developed countries throughout the world, then discusses the inherited nature of e-government from e-commerce and the differences between them. Next, it considers various barriers to the success of e-government and how to overcome those barriers. The chapter concludes with a list of the value items collected from an empirical study, and explores how they might improve e-government’s effectiveness in delivering services.
Comparing Citizens' Use of e-Government to Alternative Service Channels
Authors: Reddick Christopher G.
Published: May 2010

This chapter examines the role that e-government has over citizens’ lives when they initiate contact with their government. It also compares the influence that other contact channels have on citizens’ contacts with government. A public opinion survey is analyzed to determine what factors explain the different methods of contacting government, namely through the phone, e-government, visiting a government office, or a combination of approaches. There also is an analysis of the preferred choice of contacting government, examining different types of information or assistance that citizens’ can get from government. The results of this study indicate that e-government is just one of many possible service channels that citizens’ use, with the phone being the most commonly used. Citizens that use e-government, compared to other contact channels, are more likely to have high expectations of its impact on their search. When citizens need government information they are more likely to prefer the Internet; however, when citizens have a problem they are more likely to prefer the phone. The overall importance of the survey results indicate that e-government is just one contact channel for citizens, and resources should also be devoted towards other contact channels given their importance as well to citizens.
Digital Cities
Authors: Anthopoulos Leonidas , Fitsilis Panos
Published: May 2010

The digital cities, from their online forms such as America-On-Line and Kyoto cases, to their ubiquitous forms such as Beijing, Hull (UK) and Trikala (Greece) cases, have achieved in simplifying citizen access to Local and Central Government services. Early digital cities succeed in delivering improved public services to citizens even with no digital skills, closing digital divide and establishing digital areas of trust in local communities. This chapter presents the evolution of the digital cities, from the web to the ubiquitous architecture, which can deliver multiple services to different target groups and can behave as a common “interface” between citizens and all kinds of public agencies. The chapter will focus on the latest digital city architecture, and on the experiences from the digital city of Trikala (Greece), in order to present how digital city impacts local attitudes regarding e-Government. Moreover, the chapter will attempt to evaluate digital city’s progress and its performance concerning citizen contacts to e-Government.
Helping to Bridge the Digital Divide with Free Software and Services
Authors: Caudill Jason G.
Published: May 2010

The growing importance of digital media in citizens’ participation in government is a major issue in obtaining government services, elections and campaigning in the 21st century. In order to participate in the consumption and creation of online media, citizens must have access to, and knowledge of, appropriate technology resources. There exists a gap between those who have access to technology and those who do not A gap commonly referred to as the digital divide. While there are many different aspects to the digital divide one of them is access to the software necessary to participate in digital media. A potential solution to the software component of the digital divide is the use of open source software and free online services. Implementing these solutions can play a part in narrowing the digital divide and producing better informed citizens more capable of participating in the modern electoral process.
E-learning as a Socio-cultural System
Authors: Zuzeviciute Vaiva , Butrime Edita
Published: May 2010

The chapter analyses issues concerning the nature of virtual communities and learning in the following communities. Firstly, the discussion will focus on the question whether the very existence of technology and its ever increasing influence is an object of culture. Next, the relation between different elements of the culture (including technology) from the perspective of fostering interaction and learning will be discussed. Lastly, the specificity of the socio-cultural system of information and communication technologies (further - ICT) assisted learning together with recommendations for fostering further ICT assisted learning, e-learning and computer supported collaborative learning (CSCL) will be analysed.
Temporary Virtual Teams
Authors: Connaughton Stacey L. , Williams Elizabeth A. , Linvill Jennifer S. , O’Connor Elizabeth J. , Hayes Troy
Published: May 2010

Temporary virtual teams are common organizing forms across industries and sectors, and their members often span national, functional, and other boundaries. Many times temporary virtual team members have no prior experience working with one another, may seldom if ever meet face-to-face, and may never work together again, thus team development may occur differently than it does in long-term or in tact teams. Yet little is known about the development of temporary virtual teams and the process challenges therein. The purpose of this chapter is to contribute to this body of research by revealing how individuals who are members of a temporary virtual team experience team development. Specifically, this chapter (a) reviews two often-cited models of team development and discusses the limited body of research on virtual team development; (b) presents findings from a study of one organization’s business intelligence teams that were temporary, virtual, and global in nature; and (c) advances a research agenda for scholars in this area and recommendations to practitioners who are working in these contexts.
Virtual Mentoring
Authors: Punyanunt-Carter Narissra Maria , Hernandez Emilio S.
Published: May 2010

With the proliferation of information technology and its saturation within homes, classrooms, and organizations, the traditional landscape of mentoring relationships is quickly becoming a faceless phenomenon. Virtual mentoring is rapidly being the more preferred way to initiate mentor and protégé relationships because of constraints that prevent people from meeting face-to-face. It is through this computer-mediated method of interaction where benefits surface that increase computer-mediate dialogue, allow for the free exchange of knowledge and information regardless of an individual’s role within the interaction, and provides women a channel to voice their opinions and ideas free from gender bias. Outside of these benefits; however, limitations do exist that should be closely monitored so that the continued success of virtual mentoring can remain a viable option.
Neuroprotection and Functional Recovery Associated with Decreased Microglial Activation Following Selective Activation of mGluR2/3 Receptors in a Rodent Model of Parkinson's Disease
Authors: Chan Hugh , Paur Helen , Vernon Anthony C. , Zabarsky Virginia , Datla Krishna P. , Croucher Martin J. , Dexter David T.
Published: May 2010

Clinical trials have demonstrated positive proof of efficacy of dual metabotropic glutamate receptor 2/3 (mGluR2/3) agonists in both anxiety and schizophrenia. Importantly, evidence suggests that these drugs may also be neuroprotective against glutamate excitotoxicity, implicated in the pathogenesis of Parkinson's disease (PD). However, whether this neuroprotection also translates into functional recovery is unclear. In the current study, we examined the neuroprotective efficacy of the dual mGluR2/3 agonist, 2R,4R-4-aminopyrrolidine-2,4-dicarboxylate (2R,4R-APDC), and whether this is accompanied by behavioral recovery in a rodent 6-hydroxydopamine (6-OHDA) model of PD. We now report that delayed post lesion treatment with 2R,4R-APDC (10 nmol), results in robust neuroprotection of the nigrostriatal system, which translated into functional recovery as measured by improved forelimb use asymmetry and reduced (+)-amphetamine-induced rotation compared to vehicle treated animals. Interestingly, these beneficial effects were associated with a decrease in microglial markers in the SNc, which may suggest an antiinflammatory action of this drug.
Economic Analysis of the Production of Amylases and Other Hydrolases byAspergillus awamoriin Solid-State Fermentation of Babassu Cake
Authors: Castro Aline Machado de , Carvalho Daniele Fernandes , Freire Denise Maria Guimarães , Castilho Leda dos Reis
Published: May 2010

Amylases are one of the most important industrial enzymes produced worldwide, with their major application being in ethanol manufacturing. This work investigated the production of amylases by solid-state fermentation of babassu cake, using the filamentous fungusAspergillus awamoriIOC-3914. Lab-scale experiments were carried out to generate input data for simulations of an industrial plant for amylase production. Additionally to the target enzymes, other hydrolases (cellulases, xylanases, and proteases) were also produced, enriching the final product. The most suitable fermentation time was 144 hours, when exoamylase and endoamylase activities of 40.5 and 42.7 U g−1were achieved, respectively. A first evaluation showed a large impact of the inoculum propagation medium on production costs. Therefore, five propagation media were compared, and PDA medium presented the best cost-benefit ratio. The credits obtained from sales of fermented cake as a coproduct enabled a significant decrease in the production cost of the enzyme product, down to 10.40 USD kg−1.
Indirect Low-Intensity Ultrasonic Stimulation for Tissue Engineering
Authors: Park Hyoungshin , Yip Michael C. , Chertok Beata , Kost Joseph , Kobler James B. , Langer Robert , Zeitels Steven M.
Published: May 2010

Low-intensity ultrasound (LIUS) treatment has been shown to increase mass transport, which could benefit tissue grafts during the immediate postimplant period, when blood supply to the implanted tissue is suboptimal. In this in vitro study, we investigated effects of LIUS stimulation on dye diffusion, proliferation, metabolism, and tropomyosin expression of muscle cells (C2C12) and on tissue viability and gene expression of human adipose tissue organoids. We found that LIUS increased dye diffusion within adjacent tissue culture wells and caused anisotropic diffusion patterns. This effect was confirmed by a hydrophone measurement resulting in acoustic pressure 150–341 Pa in wells. Cellular studies showed that LIUS significantly increased proliferation, metabolic activity, and expression of tropomyosin. Adipose tissue treated with LIUS showed significantly increased metabolic activity and the cells had similar morphology to normal unilocular adipocytes. Gene analysis showed that tumor necrosis factor-alpha expression (a marker for tissue damage) was significantly lower for stimulated organoids than for control groups. Our data suggests that LIUS could be a useful modality for improving graft survival in vivo.
Dimensional reduction and the long-time behavior of Ricci flow
Authors: Lott John
Published: May 2010

If

g(t)

is a three-dimensional Ricci flow solution, with sectional curvatures that are

O(t^{−1})

and diameter that is

O(t^{1/2})

, then the pullback Ricci flow solution on the universal cover approaches a homogeneous expanding soliton.
On the integro-differential equation satisfied by the $p$-adic $\log\, Γ$-function
Authors: Friedman Eduardo
Published: May 2010

Diamond’s

p

-adic analogue

\log\, ΓD(x)

of the classical function

\log\, Γ(x)

has recently been shown to satisfy the integro-differential equation

\tag{∗}  
\int_{ℤ_p} f(x + t) dt = (x −1) f′(x) − x + 1/2\qquad   (x ∈ ℚ_p − ℤ_p),

where

\int_{ℤ_p}

is a Volkenborn integral and

f'

is the derivative of

f

. We show that this equation characterizes

\log\, ΓD(x)

up to a function with everywhere vanishing second derivative. Namely, every solution

f

of (∗) is infinitely differentiable and satisfies

f'' = \log\, ΓD''

.

We show that the set of solutions of the homogeneous equation

\int_{ℤ_p} y(x + t) dt = (x − 1) y'(x)

associated to (∗) is an infinite-dimensional commutative and associative

p

-adic algebra under the product law

(y_1 \diamond y_2)(x) : = y_2'(x)y_1(x) + y_1'(x)y_2(x) − (x − 1/2) y_1'(x)y_2'(x),

the unit being

y(x) = x − 1/2

. We also study Morita’s alternate

p

-adic analogue

\log\, ΓM

of

\log\, Γ(x)

and prove similar results.
Compactly supported cohomology of buildings
Authors: Davis Michael W. , Dymara Jan , Januszkiewicz Tadeusz , Meier John , Okun Boris
Published: May 2010

We compute the compactly supported cohomology of the standard realization of any locally finite building.
Local–global principles for embedding of fields with involution into simple algebras with involution
Authors: Prasad Gopal , Rapinchuk Andrei S.
Published: May 2010

In this paper we prove local–global principles for the existence of an embedding

(E, σ) ↪ (A, τ)

of a given global field

E

endowed with an involutive automorphism

σ

into a simple algebra

A

given with an involution

τ

in all situations except where

A

is a matrix algebra of even degree over a quaternion division algebra and

τ

is orthogonal (Theorem A of the introduction). Rather surprisingly, in the latter case we have a result which in some sense is opposite to the local–global principle, viz. algebras with involution locally isomorphic to

(A, τ)

are distinguished by their maximal subfields invariant under the involution (Theorem B of the introduction). These results can be used in the study of classical groups over global fields. In particular, we use Theorem B to complete the analysis of weakly commensurable Zariski-dense

S

-arithmetic groups in all absolutely simple algebraic groups of type different from

D_4

which was initiated in our paper [23]. More precisely, we prove that in a group of type

D_n

,

n

even

> 4

, two weakly commensurable Zariski-dense

S

-arithmetic subgroups are actually commensurable. As indicated in [23], this fact leads to results about length-commensurable and isospectral compact arithmetic hyperbolic manifolds of dimension

4n + 7

, with

n ≥ 1

. The appendix contains a Galois-cohomological interpretation of our embedding theorems.
The large sieve and random walks on left cosets of arithmetic groups
Authors: Jouve Florent
Published: May 2010

Building on Kowalski’s work on random walks on the groups

\mathrm{SL}(n,ℤ)

and

\mathrm{Sp}(2g,ℤ)

, we consider similar problems (we try to estimate the probability with which, after

k

steps, the matrix obtained has a characteristic polynomial with maximal Galois group or has no nonzero squares among its entries) for more general classes of sets: in

\mathrm{GL}(n,A)

, where

A

is a subring of

ℚ

containing

ℤ

that we specify, we perform a random walk on the set of matrices with fixed determinant

D \in A^×

. We also investigate the case where the set involved is any of the two left cosets of the special orthogonal group

\mathrm{SO}(n,m)(ℤ)

with respect to the spinorial kernel

Ω(n,m)(ℤ)

.
Small exotic Stein manifolds
Authors: Akbulut Selman , Yasui Kouichi
Published: May 2010

It is known that the only Stein filling of the standard contact structure on

S^3

is

B^4

. In this paper, we construct pairs of homeomorphic but not diffeomorphic simply connected compact Stein

4

-manifolds, for any Betti number

b_2 ≥ 1

; we do this by enlarging corks and plugs.
Cu speciation and cyanobacterial distribution in harbors subject to anthropogenic Cu inputs
Authors: Moffett James W. , Brand Larry E. , Croot Peter L. , Barbeau Katherine A.
Published: May 2010

Cu speciation was studied in four harbors on the south coast of Cape Cod, Massachusetts, that are exposed to varying degrees of Cu contamination from anthropogenic sources. Copper in waters outside the harbors was complexed by ∼10 nM of very strong chelators, twofold higher than ambient Cu concentrations. In Eel Pond (Woods Hole) and Falmouth Inner Harbor, total dissolved Cu concentrations were 7–10‐fold higher. However, because the strong chelators were saturated in these two harbors, the free Cu increased by 1,000‐fold, from ∼10−13 M to ∼10−10 M. There was no evidence for any enhanced biological production of chelators in response to the elevated Cu concentrations. However, cell densities of cyanobacteria, which have been proposed as a source of strong Cu chelators in seawater, decline drastically in the high Cu harbors. These trends are consistent with culture studies showing that Synechococcus sp., the predominant cyanophyte in these waters, shows a dramatic decrease in growth rates above a free Cu2+ level of 10−11 M. In Great Pond and Waquoit Bay, which showed no significant Cu contamination or saturation of strong ligands, cyanobacterial cell densities showed little or no decrease. Results suggest that significant anthropogenic inputs of Cu may overwhelm processes occurring in seawater that lead Cu and strong chelator concentrations to approach comparable levels.
Nutrient thresholds for bottom‐up control of macroalgal blooms on coral reefs in Jamaica and southeast Florida
Authors: Lapointe Brian E.
Published: May 2010

During the past two decades coral reefs in the greater Caribbean area have been altered by phase shifts away from corals and toward macroalgae or algal turfs. This study tested the hypothesis that because the phase shift on reefs in Jamaica and southeast Florida involved frondose macroalgae, bottom‐up control via nutrient enrichment must be a causal factor. The approach was multifaceted and included measurement of near‐bottom nutrient concentrations, salinity, nutrient enrichment bioassays, alkaline phosphatase assays, tissue C : N : P ratios, and tissue 15N : 14N (δ15N) ratios. In both locations, concentrations of dissolved inorganic nitrogen (DIN) and soluble reactive phosphorus (SRP) exceeded nutrient thresholds (∼1.0 µM DIN, 0.1 µM SRP) noted to sustain macroalgal blooms on Caribbean coral reefs. High seawater DIN : SRP ratios, alkaline phosphatase activity, and tissue C: P and N: P ratios of macroalgae on the carbonate‐rich Jamaican reef suggested SRP limitation of productivity compared to lower values of these variables on siliciclastic reefs in Florida that suggested DIN limitation. This pattern was corroborated experimentally when SRP enrichment increased Pmax (photosynthetic capacity at light saturation) of the chlorophyte Chaetomorpha linum in Jamaica compared to DIN enrichment that increased a (the photosynthetic efficiency under low irradiance) of the deeper growing chlorophyte Codium isthmocladum in southeast Florida. Increased DIN concentrations were associated with reduced salinity on both reefs, indicating submarine groundwater discharge was a significant source of DIN. Elevated δ15N values of C. isthmocladum tissue further pointed to wastewater DIN as a source of nitrogen contributing to the blooms in southeast Florida.
What is a bloom? A commentary
Authors: Smayda Theodore J.
Published: May 2010

There are at least eight different modes and mechanisms by which harmful phytoplankton species can cause mortality, physiological impairment, or other negative in situ effects. Their distinction from nonharmful phytoplankton taxa is clearly warranted. Increasing use of bloom descriptors such as “exceptional,” “unusual,” “nuisance,” and subjective reference to specific occurrences as blooms reveal widespread confusion concerning: what is a bloom?, how is it to be defined?, what is harmful?, and what distinguishes a harmful bloom from other blooms? Such efforts have been influenced by comparison with perceived spring diatom bloom characteristics. Examples, selected from among harmful bloom events, are presented to support the view that the classical focus on the spring diatom bloom has significant conceptual and operational biases as to what constitutes a bloom. This and the inexact criteria used to define a bloom compromise research on both harmful algal blooms and phytoplankton blooms in general. The subjective, differing, and arbitrary criteria used to define blooms and their presumed ecological consequences need to be replaced by a quantitatively based, ecological classification of the various types of phytoplankton blooms. The issue of what constitutes a bloom is more than simply a biomass issue.
Detection of harmful algal blooms using photopigments and absorption signatures: A case study of the Florida red tide dinoflagellate, Gymnodinium breve
Authors: Millie David F. , Schofield Oscar M. , Kirkpatrick Gary J. , Johnsen Geir , Tester Patricia A. , Vinyard Bryan T.
Published: May 2010

The utility of photopigments and absorption signatures to detect and enumerate the red tide dinoflagellate, Gymnodinium breve, was evaluated in laboratory cultures and in natural assemblages. The carotenoid, gyroxanthindiester, was an adequate biomarker for G. breve biomass; water‐column concentrations corresponded with cell standing crops and chlorophyll a concentrations during bloom events in Sarasota Bay, Florida. Unlike other carotenoids, the relative abundance of gyroxanthin‐diester did not change throughout a range of physiological states in culture and the gyroxanthin‐diester: chlorophyll a ratio exhibited little variability in a natural assemblage during bloom senescence. Stepwise discriminant analysis indicated that wavelengths indicative of in vivo absorption by accessory chlorophylls and carotenoids could correctly discern spectra of the fucoxanthin‐containing G. breve from spectra of peridinin‐containing dinoflagellates, a diatom, a haptophyte, and a prasinophyte. With the use of a similarity algorithm, the increasing contribution of G. breve was discerned in absorption spectra (and corresponding fourth‐derivative plots) for hypothetical mixed assemblages. However, the absorption properties of chlorophyll c‐containing algae vary little among taxa and it is difficult to discern the contribution of accessory chlorophylls and carotenoids caused by cell packaging. Therefore, the use of absorption spectra alone may not identify the contribution of a chlorophyll c‐containing taxon to the composite spectrum of a mixed assemblage. This difficulty in distinguishing among spectra can be minimized by using the similarity algorithm in conjunction with fourth‐derivative analysis.
Adhesion Characteristics of PDMS Surfaces During Repeated Pull‐Off Force Measurements
Authors: Kroner Elmar , Maboudian Roya , Arzt Eduard
Published: May 2010

To mimic the adhesive effects of gecko toes, artificial surfaces have been manufactured recently using polydimethylsiloxanes (PDMS). However, the effects of repeated contacts on the adhesive properties remain largely unexplored. In this paper we report on the effect of repeated pull‐off force measurements on the adhesion behavior of PDMS (polymer kit Sylgard 184, Dow Corning) tested with a borosilicate glass probe. A decrease in pull‐off force with increase in number of test cycles is found until a plateau is reached. The initial value and the rate of change in pull‐off force strongly depend on the sample preparation procedure, including curing time and cross‐linking. It is proposed that the behavior is due to steady coverage of the probe with free oligomers. The results are crucial for developing reusable, durable, and residue‐free bioinspired adhesives.
Bi‐Stable Adhesion of a Surface with a Dimple
Authors: McMeeking Robert M. , Ma Lifeng , Arzt Eduard
Published: May 2010

In this paper, we propose a new adhesive system of dimpled surfaces. The principle is derived from a contact mechanics model. The material is assumed to be linear elastic and isotropic, and attraction between the surfaces of the half‐spaces is modeled via the concept of a specific adhesion energy. It is found that large and small detachments are unstable and will either grow or shrink spontaneously when their sizes are perturbed. It is shown that this phenomenon can lead to a new bi‐stable adhesive system in which weak adhesion can be converted to strong adhesion by the application of pressure.
Deposition of crystalline copper films from tetranuclear copper (II) complexes without application of reducing atmosphere
Authors: Shahid Muhammad , Mazhar Muhammad , Hamid Mazhar , O' Brien Paul , Malik Mohammad A. , Helliwell Madeleine
Published: May 2010

Crystalline copper films were deposited by aerosol‐assisted chemical vapor deposition (AACVD) in the absence of hydrogen from two newly synthesized complexes [Cu(deae)(TFA)]4·1.25THF (1) and [Cu4(OAc)6(bdmap)2(H2O)2]·4H2O (2) [deae = N, N‐diethylaminoethanolate, TFA = trifloroacetate, OAc = acetate and bdmap = 1,3‐bis(dimethylamino)‐2‐propanolato]. These precursors were prepared in high yield using mixed ligands and crystallized in tetragonal and triclinic crystal systems with space groups 141/a and P − 1. Complexes 1 and 2 thermally decomposed at 290 and 250 °C, respectively, to yield copper films which were characterized by SEM/EDX for their morphology and composition and PXRD for their crystallinity and phase. These films have smooth morphologies with particle sizes within the range of 0.3–0.6 µm and may find applications in fabrication of ultralarge‐scale integrated circuits. Copyright © 2010 John Wiley & Sons, Ltd.