bluuebunny/crossref_metadata_2025 huggingface dataset:
Virulence Gene Regulation in
Escherichia coli
Authors: Mellies Jay L. , Barron Alex M. S.
Published: May 2014

Escherichia coli
causes three types of illnesses in humans: diarrhea, urinary tract infections, and meningitis in newborns. The acquisition of virulence-associated genes and the ability to properly regulate these, often horizontally transferred, loci distinguishes pathogens from the normally harmless commensal
E. coli
found within the human intestine. This review addresses our current understanding of virulence gene regulation in several important diarrhea-causing pathotypes, including enteropathogenic, enterohemorrhagic,enterotoxigenic, and enteroaggregative
E. coli
—EPEC, EHEC, ETEC and EAEC, respectively. The intensely studied regulatory circuitry controlling virulence of uropathogenic
E. coli
, or UPEC, is also reviewed, as is that of MNEC, a common cause of meningitis in neonates. Specific topics covered include the regulation of initial attachment events necessary for infection, environmental cues affecting virulence gene expression, control of attaching and effacing lesionformation, and control of effector molecule expression and secretion via the type III secretion systems by EPEC and EHEC. How phage control virulence and the expression of the Stx toxins of EHEC, phase variation, quorum sensing, and posttranscriptional regulation of virulence determinants are also addressed. A number of important virulence regulators are described, including the AraC-like molecules PerA of EPEC, CfaR and Rns of ETEC, and AggR of EAEC;the Ler protein of EPEC and EHEC;RfaH of UPEC;and the H-NS molecule that acts to silence gene expression. The regulatory circuitry controlling virulence of these greatly varied
E. coli
pathotypes is complex, but common themes offerinsight into the signals and regulators necessary for
E. coli
disease progression.
Virulence Gene Regulation in
Shigella
Authors: Dorman Charles J.
Published: May 2014

Shigella
species are the causative agents of bacillary dysentery in humans, an invasive disease in which the bacteria enter the cells of the epithelial layer of the large intestine, causing extensive tissue damage and inflammation. They rely on a plasmid-encoded type III secretion system (TTSS) to cause disease; this system and its regulation have been investigated intensively at the molecular level for decades. The lessons learned have not only deepened our knowledge of
Shigella
biology but also informed in important ways our understanding of the mechanisms used by other pathogenic bacteria to cause disease and to control virulence gene expression. In addition, the
Shigella
story has played a central role in the development of our appreciation of the contribution of horizontal DNA transfer to pathogen evolution.A 30-kilobase-pair "Entry Region" of the 230-kb virulence plasmid lies at the heart of the
Shigella
pathogenesis system. Here are located the
virB
and
mxiE
regulatory genes and most of the structural genes involved in the expression of the TTSS and its effector proteins. Expression of the virulence genes occurs in response to an array of environmental signals, including temperature, osmolarity, and pH.At the top of the regulatory hierarchy and lying on the plasmid outside the Entry Region is
virF
, encoding an AraC-like transcription factor.Virulence gene expression is also controlled by chromosomal genes,such as those encoding the nucleoid-associated proteins H-NS, IHF, and Fis, the two-component regulators OmpR/EnvZ and CpxR/CpxA, the anaerobic regulator Fnr, the iron-responsive regulator Fur, and the topoisomerases of the cell that modulate DNA supercoiling. Small regulatory RNAs,the RNA chaperone Hfq,and translational modulation also affect the expression of the virulence phenotypetranscriptionally and/orposttranscriptionally.
Identification of a Novel Single-Stranded Circular DNA Virus in Pig Feces
Authors: Cheung Andrew K. , Ng Terry Fei Fan , Lager Kelly M. , Alt David P. , Delwart Eric L. , Pogranichniy Roman M.
Published: May 2014

Porcine stool-associated circular virus 5 (PoSCV5) was detected in the feces of a pig with diarrhea. The complete 3,062-nucleotide genome contains two bidirectionally transcribed open reading frames (ORFs). Phylogenetic analysis of the deduced replication initiator protein (Rep) places PoSCV5 alone on a deep branch among the small circular Rep-encoding single-stranded DNA viruses.
High-Quality Draft Whole-Genome Sequences of 162 Salmonella enterica subsp.
enterica
Serovar Enteritidis Strains Isolated from Diverse Sources in Canada
Authors: Rehman Muhammad A. , Ziebell Kim , Nash John H. E. , Kropinski Andrew M. , Zong Zusheng , Nafziger Emily , Boerlin Patrick , Chui Linda , Devenish John , Bekal Sadjia , Graham Morag , Johnson Roger P.
Published: May 2014

We report the high-quality draft genome sequences of 162 strains of
Salmonella enterica
subsp.
enterica
serovar Enteritidis representing diverse phage types and pulsed-field gel electrophoresis (PFGE) profiles. The analysis of these genomes will enable the identification of markers that are useful for differentiating strains of this highly clonal serovar and will provide insights into the evolution, virulence, and epidemiology of the strains.
Draft Genome Sequence of Mycobacterium mageritense DSM 44476
T
Authors: Croce Olivier , Robert Catherine , Raoult Didier , Drancourt Michel
Published: May 2014

We report the draft genome sequence of
Mycobacterium mageritense
strain DSM 44476
T
(CIP 104973), a nontuberculosis species responsible for various infections. The genome described here is composed of 7,966,608 bp, with a G+C content of 66.95%, and contains 7,675 protein-coding genes and 120 predicted RNA genes.
The Nucleocapsid Domain of Gag Is Dispensable for Actin Incorporation into HIV-1 and for Association of Viral Budding Sites with Cortical F-Actin
Authors: Stauffer Sarah , Rahman Sheikh Abdul , de Marco Alex , Carlson Lars-Anders , Glass Bärbel , Oberwinkler Heike , Herold Nikolas , Briggs John A. G. , Müller Barbara , Grünewald Kay , Kräusslich Hans-Georg
Published: May 2014

Actin and actin-binding proteins are incorporated into HIV-1 particles, and F-actin has been suggested to bind the NC domain in HIV-1 Gag. Furthermore, F-actin has been frequently observed in the vicinity of HIV-1 budding sites by cryo-electron tomography (cET). Filamentous structures emanating from viral buds and suggested to correspond to actin filaments have been observed by atomic force microscopy. To determine whether the NC domain of Gag is required for actin association with viral buds and for actin incorporation into HIV-1, we performed comparative analyses of virus-like particles (VLPs) obtained by expression of wild-type HIV-1 Gag or a Gag variant where the entire NC domain had been replaced by a dimerizing leucine zipper [Gag(LZ)]. The latter protein yielded efficient production of VLPs with near-wild-type assembly kinetics and size and exhibited a regular immature Gag lattice. Typical HIV-1 budding sites were detected by using cET in cells expressing either Gag or Gag(LZ), and no difference was observed regarding the association of buds with the F-actin network. Furthermore, actin was equally incorporated into wild-type HIV-1 and Gag- or Gag(LZ)-derived VLPs, with less actin per particle observed than had been reported previously. Incorporation appeared to correlate with the relative intracellular actin concentration, suggesting an uptake of cytosol rather than a specific recruitment of actin. Thus, the NC domain in HIV-1 Gag does not appear to have a role in actin recruitment or actin incorporation into HIV-1 particles.

IMPORTANCE
HIV-1 particles bud from the plasma membrane, which is lined by a network of actin filaments. Actin was found to interact with the nucleocapsid domain of the viral structural protein Gag and is incorporated in significant amounts into HIV-1 particles, suggesting that it may play an active role in virus release. Using electron microscopy techniques, we previously observed bundles of actin filaments near HIV-1 buds, often seemingly in contact with the Gag layer. Here, we show that this spatial association is observed independently of the proposed actin-binding domain of HIV-1. The absence of this domain also did not affect actin incorporation and had a minor effect on the viral assembly rate. Furthermore, actin was not enriched in the virus compared to the average levels in the respective producing cell. Our data argue against a specific recruitment of actin to HIV-1 budding sites by the nucleocapsid domain of Gag.
Delayed subaponeurotic (subgaleal) fluid collection
Authors: Medows Marsha , Mohammad Nijres Bassel
Published: May 2014

A 14-week-old boy who is known to have a single right kidney presented to our emergency department with history of fever for 1 day. A sepsis work up was performed (complete blood count, blood culture, urine culture and lumbar puncture) in the emergency room. On the second day of admission he developed swelling in the parieto-occipital area. Head CT showed crescent-shaped extra cranial area of homogeneous low attenuation. He remained asymptomatic with a stable haemoglobin and haematocrit. Swelling subsequently resolved within 5 weeks.
“Why do I always see double?” A misdiagnosed case of ocular myasthenia gravis for 10 years
Authors: Mohamed Yousuf Uduman Ali , Yashodhara B M , Thanigasalam Thevi , Ting Heng Siang
Published: May 2014

A 58-year-old man presented with diplopia and partial ptosis for 10 years. It was non-progressive in nature, despite inadequate medical attention the patient received from non-specialists/general practitioners. He did not have fatigability or diurnal variation in weakness and was clinically stable without exacerbations of disease for a decade. He did not have features of Graves's disease, oculopharyngeal dystrophy, cranial nerve paralysis, polymyositis and stroke. The possibility of an atypical presentation of myasthenia gravis (MG) was considered and the patient was evaluated. Ice pack test was negative, Cogan's lid twitch (CLT) test was positive and high titres of acetylcholine receptor antibodies (AChR Ab) suggestive of MG were found. He was treated accordingly with a very good response.
Pulmonary oedema in the emergency room: what is hidden beyond an apparently common presentation
Authors: Patrício Catarina , Silva Filipa Pais da , Brotas Vítor
Published: May 2014

Cardiogenic flash pulmonary oedema is a common and potentially fatal cause of acute respiratory distress. Although it often results from acute decompensated heart failure, abrupt-onset aortic regurgitation can sharply rise cardiac filling pressure and, consequently, pulmonary venous pressure, leading to rapid fluid accumulation in the interstitial and alveolar spaces. We report a case of a 64-year-old woman admitted to the emergency department with a flash pulmonary oedema; a careful clinical investigation subsequently revealed a rare aetiology for this ‘common’ presentation. After a detailed auscultation that unmasked a diastolic cardiac murmur, an acute severe aortic insufficiency was further confirmed by echocardiography, showing inflammation and thickening of the entire aorta wall. The patient was submitted to valve replacement surgery, and histological examination, to our surprise, showed features of aortitis, remarkable for the presence of giant cells. A diagnosis of idiopathic aortitis versus inaugural giant cell arteritis was proposed and treatment started with corticosteroids.
Missed acute appendicitis presenting as necrotising fasciitis of the thigh
Authors: Taif Sawsan , Alrawi Asif
Published: May 2014

Necrotising fasciitis is a rapidly progressive soft tissue infection that leads to diffuse tissue necrosis. It is associated with systemic toxicity and rapid deterioration resulting in high mortality. Rapid diagnosis and prompt treatment are essential to improve the outcome. We report the case of a 26-year-old woman who presented with severe thigh pain and swelling associated with irritability of a few hours’ duration following 2 days history of right abdominal pain. Urgent MRI and CT scan showed features of necrotising fasciitis in the thigh spreading from an inflamed appendix. Emergency surgery was performed which revealed perforated appendix with disseminated infection in the intraperitoneal and retroperitoneal spaces as well as the right thigh. The patient rapidly deteriorated with evidence of sepsis, shock and renal impairment. In spite of surgery and all supportive measures, she succumbed shortly postoperatively. Blood culture revealedStaphylococcus aureusandStreptococci, while tissue culture showed growth ofEscherichia coliand proteus.
Resolution without treatment of granulomatous pneumonitis due to intravesical BCG for bladder cancer
Authors: Venn Robert Michael , Sharma Neel
Published: May 2014

Granulomatous pneumonitis is a well-recognised complication of intravesical BCG therapy. The mechanism is sometimes thought to be ‘hypersensitivity’ rather than infection as in most cases mycobacteria are not cultured. Despite this it is usually treated with antituberculous chemotherapy with or without corticosteroid. We describe a case of bladder cancer treated with intravesical BCG followed by a febrile illness and malaise lasting for months and the development of miliary pulmonary shadowing, which markedly improved in around 1 year without any treatment. The clinical syndrome was less severe than some others described but this case provides evidence that, at least in some cases, no specific treatment may be necessary.
A single injection of intravitreal ranibizumab in the treatment of choroidal neovascularisation secondary to optic nerve head drusen in a child
Authors: Alkin Zeynep , Ozkaya Abdullah , Yilmaz Ihsan , Yazici Ahmet Taylan
Published: May 2014

Optic nerve head drusen are acellular, calcified deposits which may be found in buried or exposed drusen form. Choroidal neovascularisation secondary to optic nerve head drusen is rarely seen in childhood. This case report summarises the clinical and therapeutic outcomes of a 13-year-old girl with unilateral choroidal neovascularisation secondary to optic nerve head drusen. The patient was successfully treated with a single intravitreal ranibizumab injection. After a month from the injection the visual acuity increased dramatically and maintained at the same level during 9 months of follow-up time. There was no complication related to the injection.
Branching laws for small unitary representations ofGL(n, ℂ)
Authors: Möllers Jan , Schwarz Benjamin
Published: May 2014

The unitary principal series representations of G = GL (n, ℂ) induced from a character of the maximal parabolic subgroup P = ( GL (1, ℂ) × GL (n - 1, ℂ)) ⋉ ℂn-1attain the minimal Gelfand–Kirillov dimension among all infinite-dimensional unitary representations of G. We find the explicit branching laws for the restriction of these representations to all reductive subgroups H of G such that (G, H) forms a symmetric pair.
Detecting the work statistics through Ramsey-like interferometry
Authors: Mazzola Laura , De Chiara Gabriele , Paternostro Mauro
Published: May 2014

Out-of-equilibrium statistical mechanics is attracting considerable interest due to the recent advances in the control and manipulations of systems at the quantum level. Recently, an interferometric scheme for the detection of the characteristic function of the work distribution following a time-dependent process has been proposed [L. Mazzola et al., Phys. Rev. Lett.110 (2013) 230602]. There, it was demonstrated that the work statistics of a quantum system undergoing a process can be reconstructed by effectively mapping the characteristic function of work on the state of an ancillary qubit. Here, we expand that work in two important directions. We first apply the protocol to an interesting specific physical example consisting of a superconducting qubit dispersively coupled to the field of a microwave resonator, thus enlarging the class of situations for which our scheme would be key in the task highlighted above. We then account for the interaction of the system with an additional one (which might embody an environment), and generalize the protocol accordingly.
Quantum optical implementation of open quantum walks
Authors: Sinayskiy Ilya , Petruccione Francesco
Published: May 2014

A quantum optical implementation of the recently proposed open quantum walks (OQWs) is suggested. In the presented quantum optical scheme a two level atom plays the role of the "walker" and the Fock states of the cavity mode correspond to the lattice sites of the OQW. Using the small unitary rotations approach the effective dynamics of the system is shown to be an OQW. The presented scheme allows for a simple physical implementation of the OQW formalism, but it can be extended to create more diverse OQWs.
Reactive transport modelling of iron–bentonite interaction within the KBS-3H disposal concept: the Olkiluoto site as a case study
Authors: Wersin Paul , Birgersson Martin
Published: May 2014

The interaction of steel with bentonite used as buffer material in high-level waste repositories may result in changes to the properties of the buffer. One of the repository designs (KBS-3H) developed by Posiva and SKB foresees the horizontal emplacement of so-called supercontainers, consisting of copper canisters surrounded by compacted bentonite and an outer perforated steel shell. The corrosion of the steel shell and the interaction of iron with the clay may impair the long-term safety functions of the buffer.

The corrosion and iron–clay interaction processes within the KBS-3H concept were assessed with a kinetically based reactive transport model and a comprehensive thermodynamic database. The large uncertainty related to precipitation rates of corrosion products and iron silicates was considered by defining a series of test cases. The results generally indicate a limited effect on the stability of montmorillonite, thus affecting only a few centimetres next to the iron source. Upon complete corrosion only insignificant changes are predicted. These results are explained by (i) the diffusional constraint of mass transfer, (ii) low solubility of corrosion products and (iii) slow transformation kinetics of montmorillonite. Model results further suggest that the largest impact arises from ‘indirect’ processes, such as microbial sulphate reduction, which may lead to a strong increase in pH.
Thermo-hydraulic modelling of the bentonite buffer in deposition hole 6 of the Prototype Repository
Authors: Malmberg D. , Kristensson O.
Published: May 2014

The Prototype Repository is an on-going full-scale trial of a final disposal of spent nuclear fuel designed in close agreement with the Swedish KBS-3V design. It provides an excellent opportunity to test our modelling capabilities and our ability to predict evolution of conditions in the planned repository for nuclear waste in Sweden. Here we describe our current efforts to simulate the experiment and compare results with available measured data. To reduce the computational demand, a modelling strategy was adopted in which large-scale low-resolution models (including the entire experiment and a large volume of surrounding rock) were used to determine boundary conditions for local-scale high-resolution models (including one deposition hole). The results obtained so far generally show reasonably good agreement with measurements available from the field experiment.
Free software developers as an occupational community
Authors: Elliott Margaret S. , Scacchi Walt
Published: May 2014

In this paper, we present results from the study of a free software development virtual organization, the GNU Enterprise (GNUe) project, and how they develop software in a globally distributed free software development project. In particular, examples of how they mitigate and resolve conflict are presented. Conflict arises over the use of a non-free tool to create GNUe graphic, and over the use of a non-free tool for GNUe documentation. The GNUe developers resolve the conflict using internet relay chat (IRC), threaded email discussions, and community digests. We characterize the GNUe developers as an occupational subculture within the occupational community of free/open source software (F/OSS) developers and show how the beliefs in free software and freedom of choice, and values in cooperative work and community assist GNUe contributors in mitigating and resolving conflict. In addition, we show how, despite fluctuating boundaries of membership in a virtual organization, daily discussions on the GNUe IRC serve to build and perpetuate the global community of GNUe contributors as well as F/OSS developers in general.
Exams
Authors: Persson Per
Published: May 2014

While many synchronous computer-mediated communication systems have failed to encourage users to make use of the expressive capabilities of their avatars, asynchronous systems may hold better chance. This paper reports on the design and user study of a message system that allows users to concatenate and annotate avatar animations and send them to peers. During three weeks, a group of 11 17-year-olds exchanged 222 animated messages in their everyday life environment. The interplay between text and animation allowed users to create significantly expressive messages. Many messages told micro-stories about fictitious and real events. Users identified with their avatars and were proud of their embodied representation. The content of messages deepened during the course of the study.
Text chat in action[5] (abstract only)
Authors: O'Neill Jacki , Martin David
Published: May 2014

Synchronous text communication is becoming recognized as a valuable workplace communication medium yet some studies of group text chat indicate that its properties can lead to interactional incoherence. We consider this issue through a detailed analytic examination of text chat transcripts by showing how participants manage their interactions through considering multiple threads, turn taking and topic change. We reveal the routine practices that participants employ to create and manage coherent interaction. These practices arise from the turn taking system in operation, which facilitates straightforward repair of misunderstandings. We conclude by considering the implications of this for design and for the organisation and management of interactions of various forms.
Expectations for a scientific collaboratory
Authors: Sonnenwald Diane H.
Published: May 2014

In the past decade, a number of scientific collaboratories have emerged, yet adoption of scientific collaboratories remains limited. Meeting expectations is one factor that influences adoption of innovations, including scientific collaboratories. This paper investigates expectations scientists have with respect to scientific collaboratories. Interviews were conducted with 17 scientists who work in a variety of settings and have a range of experience conducting and managing scientific research. Results indicate that scientists expect a collaboratory to: support their strategic plans; facilitate management of the scientific process; have a positive or neutral impact on scientific outcomes; provide advantages and disadvantages for scientific task execution; and provide personal conveniences when collaborating across distances. These results both confirm existing knowledge and raise new issues for the design and evaluation of collaboratories.
Increasing workplace independence for people with cognitive disabilities by leveraging distributed cognition among caregivers and clients[11] (abstract only)
Authors: Carmien Stefan , DePaula Rogerio , Gorman Andrew , Kintsch Anja
Published: May 2014

In this paper we describe a current group configuration that is used to support people with cognitive disabilities (hereinafter referred to as "clients") in the workplace. A client receiving face-to-face, often one-to-one assistance from a dedicated human job coach is characteristic of this "traditional" model. We compare this traditional model with other group configurations that are used in cooperative and distributed work practices. In so doing, we highlight requirements that are unique to task support for people with cognitive disabilities. A survey of technologies that have been developed to provide clients with greater levels of independence is then presented. These endeavors often attempt to replace human job coaches with computational cognitive aids. We discuss some limitations of such approaches and then present a model and prototype that extends the computational job coach by incorporating human caregivers in a distributed one-to-many support system.
Supporting activity-centric collaboration through peer-to-peer shared objects[13] (abstract only)
Authors: Geyer Werner , Vogel Jürgen , Cheng Li-Te , Muller Michael
Published: May 2014

We describe a new collaborative technology that is mid-way between the informality of email and the formality of shared workspaces. Email and other ad hoc collaboration systems are typically lightweight and flexible, but build up an unmanageable clutter of copied objects. At the other extreme, shared workspaces provide formal, structured collaboration, but are too heavyweight for users to set up. To bridge this gap between the ad hoc and formal, this paper introduces the notion of "object-centric sharing", where users collaborate in a lightweight manner but aggregate and organize different types of shared artifacts into semi-structured activities with dynamic membership, hierarchical object relationships, as well as real-time and asynchronous collaboration. We present a working prototype implemented with a replicated peer-to-peer architecture, which we describe in detail, and demonstrate its performance in synchronous and asynchronous modes.
Why do we ReachOut?
Authors: Jacovi Michal , Soroka Vladimir , Ur Sigalit
Published: May 2014

Collaboration plays a vital role in today's new business environment. Knowledge that resides within people's heads has become an invaluable resource. Many formal tools, such as e-mail or teamrooms, have been introduced to support formal collaboration and have been studied extensively. However, support for informal communication is still in its infancy. Much work has been done to analyze the functions that informal communication plays in the workplace. Recently, several studies have evaluated the roles that instant messaging (IM) plays in similar settings. Research shows that in the workplace, IM is used primarily for work-related purposes and accelerates the completion of important business tasks. Clearly, new tools that combine both formal and informal interaction can bring organizations tremendous rewards. ReachOut is a tool for semi-persistent collaboration and peer support developed by the Collaboration Technologies Group at the IBM Haifa Research Lab. This paper studies the role ReachOut plays in the workplace. We analyzed the collaboration activity of the community of IBM Haifa Labs employees who used ReachOut for a period of two months. As a result, we summarize the important functions played by tools that bridge between formal and informal communication in a workplace-based community.
Improving individual and organizational performance through communities of practice[23] (abstract only)
Authors: Millen David R. , Fontaine Michael A.
Published: May 2014

Organizations have been increasingly providing communities of workers with resources, time, physical space and collaborative technologies to enhance the exchange and flow of knowledge and information. In this paper the results of a multi-organizational survey of four work-based communities is presented. These results offer insights into the resource usage, time use for various work activities, and reported individual, community and organizational benefits. A descriptive model is developed and discussed to show the relationships between community participation, time use, and individual and organizational outcomes.
Owner/user role in computational grid extension by non-dedicated resources[25] (abstract only)
Authors: Martinovic Goran
Published: May 2014

Engagement of non-dedicated machines in the computational grid requires special attention by mapping. In addition to application, platform and mapping parameters, a human as a resource owner plays an extremely important role. The problem is easier for the owner/user who also requires grid services at the same time. The grid can provide a powerful support to CSCW. Resource concession can also be treated as cooperation in the grid extension. The proposed resource extension model is based on meeting scheduling. This model puts a group member into a competitive position, since he becomes responsible for his organizational and infrastructure capabilities. He tends to concede the idle capacity to the grid in order to be able to use services provided by that powerful virtual machine.
Process inheritance and instance modification[26] (abstract only)
Authors: Yang Guangxin
Published: May 2014

Process technologies play an increasingly important role as the world is being digitalized in nearly every corner. The major obstacles to their massive deployment include reusability and adaptivity. This paper addresses the two crucial problems with one single solution: process inheritance. We discuss what process inheritance is, what mechanisms are needed to support it, and how it can be used to handle exceptions effectively. The ideas and mechanisms are implemented in the runtime system of a process language named P.
Awareness support in a groupware widget toolkit[29] (abstract only)
Authors: Hill Jason , Gutwin Carl
Published: May 2014

Group awareness is an important part of synchronous collaboration, and support for group awareness can greatly improve groupware usability. However, it is still difficult to build groupware that supports group awareness. To address this problem, we have developed the MAUI toolkit, a Java toolkit with a broad suite of awareness-enhanced UI components. The toolkit contains both extensions of standard Swing widgets, and groupware-specific components such as telepointers. All components have added functionality for collecting, distributing, and visualizing group awareness information. The toolkit packages components as JavaBeans, allowing wide code reuse, easy integration with IDEs, and drag-and-drop creation of working group-aware interfaces. The toolkit provides the first ever set of UI widgets that are truly collaboration-aware, and provides them in a way that greatly simplifies the construction and testing of rich groupware interfaces.
Shaping technology across social worlds
Authors: Mark Gloria , Poltrock Steven
Published: May 2014

In this paper, we draw on theory about social worlds to analyze how different organizational contexts affect groupware adoption. We report on a study of the adoption of data conferencing in a large distributed organization. Our data show that the diffusion process, which was driven by the users, was a result of communication and transformation of the technology across differnet social worlds. We also discovered that membership in multiple social worlds in an organization creates a tension for the potential adopter who is in a distributed team. To function effectively, team members must uniformly adopt the technology, yet some may face resistance at their organizational homes. Our case study showed that adoption was affected by organizational sites having conflicting views of the value of collaboration. different amounts and needs for resources, and different acceptance of technology standards. Potential technology adopters on distributed teams are faced with conflicting loyalties, constraints, and requirements between their distributed collaborations and organizational homes.
Introduction to the special issue
Authors: Klamma Ralf , Rohde Markus , Stahl Gerry
Published: May 2014

This very special (and final) issue of the
ACM SIGGROUP Bulletin
presents products of a workshop on
Community-Based Learning: Explorations into Theoretical Groundings, Empirical Findings and Computer Support
that was held at the International Conference of the Learning Sciences (ICLS 2004).
Us, ourselves, and we
Authors: Rohde Markus , Shaffer David Williamson
Published: May 2014

In a recent Workshop on community-based learning at the 6th International Conference on Learning Sciences (ICLS 2004), one persistent theme was the variety of terms used to describe collections of people (group, community, network, collective) and components of interaction (culture, identity, collaboration, cooperation) in group learning activities. Here, we describe some of the thinking that emerged in those discussions, not as a comprehensive literature review or completely elaborated socio-cultural theory, but rather as an invitation to further discussion. We suggest that a
group
is the most generic and general social category: all of the analytical units in the literature on collective learning - teams, social networks, and communities - are groups. We argue that these other terms have additional structural characteristics that make them distinct subsets of the generic term
group.
For example, a
team
is a group with a common task, a
network
is a group with strong social ties, and a
community
is a group with a shared culture. We propose a two-dimensional space of social organizations characterized by
shared culture
and
shared interaction
, and suggest both individuals and collectives show a developmental history through the space of collectives, moving from loose group affiliation to increasing identification with, development of, and participation in shared interactions within a shared culture. This analysis suggests, we argue, that: (a) tools to support "collaboration" may need different affordances for different kinds of collectives; (b) understanding different kinds of collectives requires different methodologies; and (c) culture plays a prominent role in the space of collectives we describe, and thus, we argue, should play a significant role in the analysis of any community. We hope that this brief discussion will lead to further work on the social entities within which group learning takes place, on the processes of learning in such settings, and on the technologies that can support such processes.
Re-presenting collective learning
Authors: Forsyth Lachlan , Schaverien Lynette
Published: May 2014

Professional development is increasingly conceived as a sustained group or community process, often supported by online technologies. Yet despite the enthusiasm for online communities of practice [40], and the innovative educational contexts being developed to support them, the reality of developing and maintaining a critical mass of teacher engagement is proving to be challenging (for example, the Inquiry Learning Forum (ILF) [4]; the Hawaii Networked Learning Communities (HNLC) [37]). Teacher educators and designers of technological learning environments continually strive to maximize the value of teacher engagement in such contexts, yet the conditions under which social learning and collaboration become an appropriate strategy for teachers remain unclear [4; 19]. Furthermore, contemporary research from evolutionary psychology [27] and modeling of cultural transmission [5] suggests the likelihood that professional development in sustained groups would involve subtle yet influential
social
learning strategies. For example, decisions regarding the adequacy of a particular concept or professional behavior may be influenced by the status of the group member advocating it, the frequency of the behavior in the group, or even which idea or behavior was offered to the group first [1].
Communities of reflection-practice and clash of communities
Authors: Strobel Johannes
Published: May 2014

Grounded in constructivist instructional philosophy [5] and a view that the purpose of schooling is to prepare students for a changing workplace [7; Partnership for 21
st
Century Skills, www.21stcenturyskills.org], learning scientists turned to communities of practice (CoPs) to get inspiration for the design of learning activities in classrooms that resemble the 'authentic' and 'real-world' situations found in CoPs outside of schools. For domains that are naturally close to the workforce, like domains in the sciences, technology, engineering, math, and others, it seems a perfect match and classroom environments are transformed to resemble CoPs [4; 6; 9].
Supporting communication and knowledge creation in digitally networked communities in the humanities
Authors: Klamma Ralf , Spaniol Marc
Published: May 2014

Scholarly communication in the humanities heavily depends on the discursive nature of knowledge creation and the media that is in use. This communication has changed over the centuries due to the evolution of media, altering not only the communicational culture of scholars regarding their archives and text production strategies but also the communication situation in society, leading to scientific, artistic, and societal revolutions. The change from scroll to book in the edition of the Babylonian Talmud is a good example of such a medium revolution. The interdisciplinary collaborative research center "Media and cultural communication"
1
was founded in 1999 to research the nature and impact of media on the discourses in cultural communication. Historically, and by creating new interdisciplinary workplaces for scientists in the 21st century, our subproject analyzes the impact of networked information systems on cooperation and knowledge organization in scientific communities and public debates.
Student communities in a distance-learning environment
Authors: Isckia Thierry , Delalonde Charles
Published: May 2014

Distance Education (DE) is becoming increasingly important as its rapid growth rates demonstrate. However, recent statistics on DE show low retention rates and a poor return on investment (ROI) in various programs. We need a better understanding of what are the critical success factors for DE environments for all constituencies (students, instructors, and institutions). We still misinterpret the reality of this kind of practice, both from the teacher's and the learner's point of view [1]. In this article, we focus on the collective dimension of the learning environments. In fact, entering a virtual learning community appears as a rational choice for the students to retrieve information more rapidly [3] and examine with available peers the actual content. But, students occasionally express a natural anxiety about sharing their difficulties with strangers, which partially explains the barriers in establishing trusting and caring learning communities [2]. Well-sequenced pedagogical courses and frequent contacts with the professor seem to strengthen the cohesion and integration of the students in a group. Consequently, educational choices and the global architecture of the course, by influencing the formation of these groups, try to compensate --- at least partially --- for the deficiencies of DE. The goal of this paper is to propose solutions to overcome low retention rates and ROI in order to deploy an efficient DE program using the key solution of a web-based course in an American public university.
Building learning communities by enhancing social presence
Authors: Hung Woei
Published: May 2014

Lewis, Snow, Farris, et al. stated in the National Center for Education Statistics that "distance education appears to have become a common feature of many postsecondary education institutions and...it will become only more common in the future" [3]. In the wave of migration to new instructional delivery modes, it is necessary for us to critically examine some issues that have arisen, in order to reach an optimal solution for both the students and the instructors. One of the inevitable tradeoffs in an online learning environment is a decrease in the quality of social interaction. Social interaction is innate in traditional face-to-face classrooms. It is not only a critical element in helping the learners to develop a sense of belongingness within a learning community, but also determines the dynamics of the learning community, which greatly influence the students' learning outcomes. Among the essential components of a community, interaction between the members is deemed to be the one crucial factor that makes a community alive. Researchers agree that helping students develop a sense of community is an important aspect in promoting positive learning experiences and better learning outcomes in distance learning environments [7].
A framework to support collaboration in heterogeneous environments
Authors: Bharadwaj Vijayanand , Reddy Y. V. Ramana
Published: May 2014

We recognize that a variety of tools and groupware used by distributed teams can strongly influence the manner in which team members can obtain awareness of the project. Considering that is often a necessity and even advantageous to use a variety of applications as well as the fact that project awareness is most essential, we propose an "Awareness Framework" that seeks to bind heterogeneous tools and groupware. This research discusses the architecture of the framework as well as a process that is necessary to manage it and project awareness.
Web-based collaboration in flexible engineering education
Authors: Nguyen Anh-Vu , Gillet Denis
Published: May 2014

This paper presents an innovative approach to sustain collaborative hands-on activities in flexible engineering education. The paper presents our research context, our objectives as well as some preliminary results. The main issues addressed include (i) object-oriented model for collaboration in Web-based learning environment for engineering education (ii) continuity of interaction in flexible engineering education (iii) awareness in Web-based learning environment, and (iv) evaluation methods and metrics. This doctoral research work is currently performed at the School of Engineering, EPFL.
Distance education in a global age
Authors: Amant Kirk St.
Published: May 2014

As global online access grows, so does the prospect that online classes will contain students from various cultures and countries. Within this educational environment, cultural differences can affect how students share ideas, comprehend concepts, and access course-related materials. Effective instruction in international online classes therefore requires instructors to address those cultural differences that could most greatly affect learning in such environments. This essay provides an overview of some of the more problematic factors related to international online classes. In examining these factors, the essay also presents strategies for mitigating related problems. The essay then concludes with an annotated list of free online resources educators can use to learn more about cultural factors that could affect learning in online classrooms.
Design and evaluation of an online learning community
Authors: Alem Leila , Kravis Simon
Published: May 2014

An important aspect of online learning community development is to evaluate whether or not a particular online learning community is successful. This paper presents preliminary findings in developing and evaluating an online learning community using Preece's framework for designing and evaluating the success of online communities. The community consisted of CSIRO staff interested in what constitutes values in water use in Australia and how to account for such values. About 400 staff participated in the discussion, that was limited to two weeks. Daily observations of the content and participation were made, and participants were surveyed after the discussion had closed. A total of about 17,000 words of discussion data have been analyzed using purpose-built software. Initial findings using Preece's criteria indicate that the online learning community was successful from a sociability perspective. We found that the number of participants was higher than expected, the volume of emails was high, participants referred to each other quite regularly, the discussion stayed on topic most of the time, the participants saw value in the discussion (even the lurkers), and participants were satisfied with the social interaction within the community.
Learning to fly in persistent digital worlds
Authors: Papargyris Anthony , Poulymenakou Angeliki
Published: May 2014

This paper discusses virtual communities' formation and skill development through the process of participation in collective practices in on-line role-playing game environments. The study that follows is mainly based on the participant observation of players acting in two popular Massively Multiplayer Online Role Playing Games. Data have been collected through participation and observation of players and their unfolding practices in forming and maintaining such communities. The objective was to document these practices and to study virtual game environments in order to understand learning opportunities within and among these communities, and to identify design elements of the game that cultivate community building. The primary unit of analysis is the in-game communities known as 'guilds'. Research findings indicate that in such multicultural and anonymous environments, many learning processes are evolving that affect both players' understanding of the game's state, and their social interaction and communication skills.
Do culture and technology interact?
Authors: Zorn Isabel
Published: May 2014

The following article aims at providing reflections on electronic interculturality and at investigating areas on action for conceptualizing and maintaining international communities. The main question investigated will be: What is specific about intercultural communication in a virtual community and where does this need to be considered? Relevant aspects and categories of virtual intercultural communication will be pointed out from both a software engineering and a communication perspective. The paper will look at opportunities and challenges of virtual communities for intercultural communication with the objective to enable barrier free communication, equal access opportunities and mutual exchange. Areas to be considered when designed the electronic media for the communities are identified.
MOO
Authors: Che Haoyang , Zhang Qiangfeng
Published: May 2014

A MOO is a text-based, multi-participant, user-extensible, object-oriented virtual environment in which users can interact with each other via the Internet polysynchronously (in synchronous and asynchronous time) and build meaningful artifacts. MOO technology provides us a single, low-cost, highly supportive venue for online activities. However, it is one of, the forgotten, virtual community border technologies. This paper gives an introduction to MOOs, presents the advantages and disadvantages of MOOs, and discusses the future potentialities of the MOO platform. Will MOOs experience a rebirth, or will they continue to stagnate as a legacy technology?
Reflexivity in e-science
Authors: Hunsinger Jeremy
Published: May 2014

The social and policy aspects of e-science are becoming more important as the social and technical infrastructure for it progresses. This essay presents the idea that we should pursue a reflexive perspective in its development, keeping in mind that e-science has the capacity to radically restructure current power relations in research institutions. However, it probably will not cause radical change, as much as exacerbate the already difficult situations that the virtual communities of researchers face in the entrepreneurial university.
CSCL report: human computer interaction and educational tools (HCI-ET) conference report: May 18–27, 1997 Sozopol, Bulgaria
Authors: McManus Margaret M.
Published: May 2014

HCI-ET, a working conference of the IFIP WG 3.3, addressed the technologies and issues of Human Computer Interaction (HCI) regarding educational tools. The managerial and procedural operations of the conference were handled electronically through e-mail and the World Wide Web, two of the most common technologies of groupware. The conference Web site bttp://www-it.fmi.uni-sofia.bg/HCIET/describes the goals of the conference as well as abstracts of the papers, and serves as the primary resource for the material in this report.This report focuses on the topics which concern Computer-Supported Collaborative Learning (CSCL), especially Web-based education and training, and computer-supported collaborative skills. Additional articles on other issues in HCI were presented. The full articles will be published in book format.