bluuebunny/crossref_metadata_2025 huggingface dataset:
FliG Subunit Arrangement in the Flagellar Rotor Probed by Targeted Cross-Linking
Authors: Lowder Bryan J. , Duyvesteyn Mark D. , Blair David F.
Published: August 2005

FliG is a component of the switch complex on the rotor of the bacterial flagellum. Each flagellar motor contains about 25 FliG molecules. The protein of
Escherichia coli
has 331 amino acid residues and comprises at least two discrete domains. A C-terminal domain of about 100 residues functions in rotation and includes charged residues that interact with the stator protein MotA. Other parts of the FliG protein are essential for flagellar assembly and interact with the MS ring protein FliF and the switch complex protein FliM. The crystal structure of the middle and C-terminal parts of FliG shows two globular domains joined by an α-helix and a short extended segment that contains two well-conserved glycine residues. Here, we describe targeted cross-linking studies of FliG that reveal features of its organization in the flagellum. Cys residues were introduced at various positions, singly or in pairs, and cross-linking by a maleimide or disulfide-inducing oxidant was examined. FliG molecules with pairs of Cys residues at certain positions in the middle domain formed disulfide-linked dimers and larger multimers with a high yield, showing that the middle domains of adjacent subunits are in fairly close proximity and putting constraints on the relative orientation of the domains. Certain proteins with single Cys replacements in the C-terminal domain formed dimers with moderate yields but not larger multimers. On the basis of the cross-linking results and the data available from mutational and electron microscopic studies, we propose a model for the organization of FliG subunits in the flagellum.
SarA Positively Controls Bap-Dependent Biofilm Formation in
Staphylococcus aureus
Authors: Trotonda María Pilar , Manna Adhar C. , Cheung Ambrose L. , Lasa Iñigo , Penadés José R.
Published: August 2005

The biofilm-associated protein Bap is a staphylococcal surface protein involved in biofilm formation. We investigated the influence of the global regulatory locus
sarA
on
bap
expression and Bap-dependent biofilm formation in three unrelated
Staphylococcus aureus
strains. The results showed that Bap-dependent biofilm formation was diminished in the
sarA
mutants by an
agr
-independent mechanism. Complementation studies using a
sarA
clone confirmed that the defect in biofilm formation was due to the
sarA
mutation. As expected, the diminished capacity to form biofilms in the
sarA
mutants correlated with the decreased presence of Bap in the bacterial surface. Using transcriptional fusion and Northern analysis data, we demonstrated that the
sarA
gene product acts as an activator of
bap
expression. Finally, the
bap
promoter was characterized and the transcriptional start point was mapped by the rapid amplification of cDNA ends technique. As expected, we showed that purified SarA protein binds specifically to the
bap
promoter, as determined by gel shift and DNase I footprinting assays. Based on the previous studies of others as well as our work demonstrating the role for SarA in
icaADBC
and
bap
expression (J. Valle, A. Toledo-Arana, C. Berasain, J. M. Ghigo, B. Amorena, J. R. Penades, and I. Lasa, Mol. Microbiol. 48:1075-1087), we propose that SarA is an essential regulator controlling biofilm formation in
S. aureus
.
The Large First Periplasmic Loop of SecD and SecF Plays an Important Role in SecDF Functioning
Authors: Nouwen Nico , Piwowarek Magdalena , Berrelkamp Greetje , Driessen Arnold J. M.
Published: August 2005

A remarkable feature of proteins of the SecD and SecF family involved in protein translocation is that they possess a very large first periplasmic domain. Here we report that this large first periplasmic domain is not required for the SecD-SecF interaction but that it is important for catalyzing protein translocation.
ESSENTIAL REPRESENTATIONS OF C*-CORRESPONDENCES
Authors: HIRSHBERG ILAN
Published: August 2005

Let E be a C*-correspondence over a C*-algebra [Formula: see text] with non-degenerate faithful left action. We show that E admits sufficiently many essential representations (i.e. representations ψ such that [Formula: see text]) to recover the Cuntz–Pimsner algebra [Formula: see text].
Determining approximate shortest paths on weighted polyhedral surfaces
Authors: Aleksandrov L. , Maheshwari A. , Sack J.-R.
Published: August 2005

In this article, we present an approximation algorithm for solving the single source shortest paths problem on weighted polyhedral surfaces. We consider a polyhedral surface
P
as consisting of
n
triangular faces, where each face has an associated positive weight. The cost of travel through a face is the Euclidean distance traveled, multiplied by the face's weight. For a given parameter ε, 0 <ε < 1, the cost of the computed paths is at most 1 + ε times the cost of corresponding shortest paths. Our algorithm is based on a novel way of discretizing polyhedral surfaces and utilizes a generic greedy approach for computing shortest paths in geometric graphs obtained by such discretization. Its running time is
O(C(P)
n
/√ε log
n
/ε log 1/ε) time, where
C(P)
captures geometric parameters and the weights of the faces of
P
.
Formal interpreters for diagram notations
Authors: Baresi Luciano , Pezzè Mauro
Published: August 2005

The article proposes an approach for defining extensible and flexible formal interpreters for diagram notations with significant dynamic semantics. More precisely, it addresses semi-formal diagram notations that have precisely-defined syntax, but informally defined (dynamic) semantics. These notations are often flexible to fit the different needs and expectations of users. Flexibility comes from the incompleteness or informality of the original definition and results in different interpretations.The approach defines interpreters by means of a mapping onto a semantic domain. Two sets of rules define the correspondences between the elements of the diagram notation and those of the semantic domain, and between events and states of the semantic domain and visual annotations on the elements of the diagram notation.Flexibility also leads to notation families, that is, sets of notations that share core concepts, but present slightly different interpretations. Existing approaches usually interpret these notations in isolation; the approach presented in this article allows the interpretation of a family as a whole. The feasibility of the approach is demonstrated through a prototype generator that allows users to implement special-purpose interpreters by defining relatively small sets of rules.
Building disappearing computers
Authors: Russell Daniel M. , Streitz Norbert A. , Winograd Terry
Published: August 2005

A trio of systems illustrates the challenges of designing large displays for use in ubiquitous computing environments that are, indeed, unremarkable.
Prototyping
Authors: Holmquist Lars Erik
Published: August 2005

They believe that planes come from paradise---their ancestors sent them. But the white man, a crafty pirate, manages to get his hands on them by attracting them into a big trap of an airport. You build your plane too, and wait with faith. Sooner of later, your ancestors will discover the white man's trap and will guide the planes on your landing strip. Then you will be rich and happy.

---
Narration from the film
Mondo Cane

, 1962
Motion prediction for caching and prefetching in mouse-driven DVE navigation
Authors: Chan Addison , Lau Rynson W. H. , Ng Beatrice
Published: August 2005

A distributed virtual environment (DVE) allows geographically separated users to participate in a shared virtual environment via connected networks. However, when the users are connected by the Internet, bandwidth limitation and network latency may seriously affect the performance and the interactivity of the system. This explains why there are very few DVE applications for the Internet. To address these shortcomings, caching and prefetching techniques are usually employed. Unfortunately, the effectiveness of these techniques depends largely on the accuracy of the prediction method used. Although there are a few methods proposed for predicting 3D motion, most of them are primarily designed for predicting the motion of specific objects by assuming certain object motion behaviors. We notice that in desktop DVE applications, such as virtual walkthrough and network gaming, the 2D mouse is still the most popular device used for navigation input. Through studying the motion behavior of a mouse during 3D navigation, we have developed a hybrid motion model for predicting the mouse motion during such navigation---a linear model for prediction at low-velocity motion and an elliptic model for prediction at high-velocity motion. The predicted mouse motion velocity is then mapped to the 3D environment for predicting the user's 3D motion. We describe how this prediction method can be integrated into the caching and prefetching mechanisms of our DVE prototype. We also demonstrate the effectiveness of the method and the resulting caching and prefetching mechanisms through extensive experiments.
Integrated modeling
Authors: Delen Dursun , Dalal Nikunj P. , Benjamin Perakath C.
Published: August 2005

Current business modeling methods are one-dimensional. Here, an integrated modeling approach helps decision makers study the enterprise as a whole from multiple perspectives.
IT is not for everyone in China
Authors: Quan Jing , Hu Qing , Wang Xinan
Published: August 2005

A 2004 report by consulting firm Gartner Dataquest forecasts that the worldwide market for IT services will top $762.3 billion in 2008, up from $608.1 billion in 2004. The Asia-Pacific region's compound annual growth rate of 9.7% (projected 2003--2008) leads the world. IT services revenue in the region will thus top $43.9 billion in 2008, as China surpasses South Korea to become one of the three largest IT services markets in the region, along with Japan and Australia.The growth of China's enterprise software market in 2003--2004 reflected this broader trend. Sales of enterprise resource planning (ERP) software, according to a 2004 China Computer World (CCW) research survey, totaled 1.19 billion yuan ($144 million U.S.) in the first half of 2004, up 29% over the same period a year earlier. Human resources software posted sales growth of 80.4% for the first half of 2004 over the same period a year earlier. On the other hand, customer relationship management software sales barely crossed the 200-million-yuan mark, up 2.2% over the same period a year earlier. Nonetheless, the CCW survey anticipated a customer relationship software boom in five years when Chinese companies have had enough time to digest their operational-level IT investments and move on to more sophisticated management software. Despite the mixed outcomes in terms of ERP implementation and use in China [4], the CCW survey found that 47% of Chinese enterprises had installed ERP modules, with an annual growth rate of 5% for new installations.
A systematic approach to static access control
Authors: Pottier François , Skalka Christian , Smith Scott
Published: August 2005

The Java Security Architecture includes a dynamic mechanism for enforcing access control checks, the so-called
stack inspection
process. While the architecture has several appealing features, access control checks are all implemented via dynamic method calls. This is a highly nondeclarative form of specification that is hard to read, and that leads to additional run-time overhead. This article develops type systems that can statically guarantee the success of these checks. Our systems allow security properties of programs to be clearly expressed within the types themselves, which thus serve as static declarations of the security policy. We develop these systems using a systematic methodology: we show that the security-passing style translation, proposed by Wallach et al. [2000] as a
dynamic
implementation technique, also gives rise to
static
security-aware type systems, by composition with conventional type systems. To define the latter, we use the general HM(
X
) framework, and easily construct several constraint- and unification-based type systems.
Efficient techniques for transition testing
Authors: Liu Xiao , Hsiao Michael S. , Chakravarty Sreejit , Thadikaran Paul J.
Published: August 2005

Scan-based transition tests are added to improve the detection of speed failures in sequential circuits. Empirical data suggests that both data volume and application time will increase dramatically for such transition testing. Techniques to address the above problem for a class of transition tests, called enhanced transition tests, are proposed in this article.The first technique, which combines the proposed transition test chains with the ATE repeat capability, reduces test data volume by 46.5% when compared with transition tests computed by a commercial transition test ATPG tool. However, the test application time may sometimes increase. To address the test time issue, a new DFT technique, Exchange Scan, is proposed. Exchange scan reduces both data volume and application time by 46.5%. These techniques rely on the use of hold-scan cells and highlight the effectiveness of hold-scan design to address test time and test data volume issues. In addition, we address the problem of yield loss due to incidental
overtesting
of functionally-untestable transition faults, and we formulate an efficient adjustment to the algorithm to keep the overtest ratio low. Our experimental results show that up to 14.5% reduction in overtest ratio can be achieved, with an average overtest reduction of 4.68%.
Voices of women in a software engineering course: reflections on collaboration
Authors: Berenson Sarah B. , Slaten Kelli M. , Williams Laurie , Ho Chih-Wei
Published: August 2005

Those science, mathematics, and engineering faculty who are serious about making the education they offer as available to their daughters as to their sons are, we posit, facing the prospect of dismantling a large part of its traditional pedagogical structure, along with the assumptions and practice which support it. [Seymour and Hewett 1997].Prior research indicates that female students can be concerned about the insularity of working alone for long periods of time, as they perceive to be the case with computer science and information technology careers. We studied an advanced undergraduate software engineering course at North Carolina State University to characterize the potential of collaborative learning environments created via pair-programming and agile software development to ameliorate this concern. A collective case study of three representative women in the course revealed that they held the following four themes in common: working with others; productivity; confidence; and interest in IT careers. Three conjectures concerning collaboration emerged from our study, including the importance of face-to-face meetings, an increased confidence among women based on product quality, and a reduction in the amount of time spent on assignments. While our findings are not generalized to early undergraduate courses, the young women we studied were at a critical junction in deciding whether to pursue a career in IT upon their near-term graduation. Additionally, we propose a model for future testing with both males and females that connects these three factors with an increased interest in IT careers.
Business types, e-strategies, and performance
Authors: Lai Vincent S. , Wong Bo K.
Published: August 2005

Of the multitude of dot-coms in existence in the 1990s, only a fraction survived the crash of the e-commerce (EC) market in the summer of 2000. These companies must now rediscover the principles that governed businesses prior to the EC era. Dot-coms must be rebuilt and transformed to face the new economy: not only must they devise innovative e-strategies [1], but they must also restructure around new business models. After such reengineering efforts, some dot-coms have steadily recuperated from the debacle, but many more are still struggling.Little research has compared the performance of companies with different business types, including B2B, B2C, and non-EC, and explored their endeavors to continue after the EC crash. In this article we report the results of our investigation of EC companies in the aftermath of the crash, with particular emphasis on their performance as compared to their counterpart non-EC companies, and in light of their EC operations experience. We also identify e-strategies introduced by different companies and evaluated their effectiveness by correlating them with company performance, and examine whether this strategy-performance relationship is contingent upon business type.Our study adopted a three-stage data collection method. The first stage involved an analysis of the annual reports of 103 companies listed in the Growth Enterprise Market (GEM), which was established by the Stock Exchange of Hong Kong in November 1999. In addition, 16 EC companies with similar histories, reputations, and backgrounds were included. Although GEM imposes no restrictions on the nature of an applicant's business, many of its listed companies come from IT or EC-related fields. Classification of EC and non-EC companies was based on the Dow Jones Internet Index, which classifies firms as EC companies if they derive more than 50% of revenue from EC activities. The latest reports of these 119 companies were thoroughly analyzed to derive financial indices of performance.
The (gradually) changing face of state IT jobs
Authors: Pawlowski Suzanne D. , Datta Pratim , Houston Andrea L.
Published: August 2005

Working for the state once meant long hours, low pay, and lots of red tape. That picture has certainly changed in recent years, as state governments plan to compete with the private sector for top IT talent.
Health care and services delivery systems as complex adaptive systems
Authors: Tan Joseph , Wen H. Joseph , Awad Neveen
Published: August 2005

Alan Turing and John von Neumann pioneered the study of complex systems. In analyzing feedback processes, they were interested in how complex interacting systems can respond to new information. Among other things, they found that some systems with many interactions among highly differentiated parts can produce surprisingly simple, predictable behavior (such as a programmable mechanical routine or process), while others generate behavior that may be impossible to predict, even though these systems feature simple laws and few actors or agents (such as an evolving living organism).
Exchanging intensional XML data
Authors: Milo Tova , Abiteboul Serge , Amann Bernd , Benjelloun Omar , Ngoc Fred Dang
Published: August 2005

XML is becoming the universal format for data exchange between applications. Recently, the emergence of Web services as standard means of publishing and accessing data on the Web introduced a new class of XML documents, which we call
intensional
documents. These are XML documents where some of the data is given explicitly while other parts are defined only intensionally by means of embedded calls to Web services.When such documents are exchanged between applications, one has the choice of whether or not to materialize the intensional data (i.e., to invoke the embedded calls) before the document is sent. This choice may be influenced by various parameters, such as performance and security considerations. This article addresses the problem of guiding this materialization process.We argue that---like for regular XML data---schemas (à la DTD and XML Schema) can be used to control the exchange of intensional data and, in particular, to determine which data should be materialized before sending a document, and which should not. We formalize the problem and provide algorithms to solve it. We also present an implementation that complies with real-life standards for XML data, schemas, and Web services, and is used in the Active XML system. We illustrate the usefulness of this approach through a real-life application for peer-to-peer news exchange.
Trusted paths for browsers
Authors: Ye Zishuang (Eileen) , Smith Sean , Anthony Denise
Published: August 2005

Computer security protocols usually terminate in a computer; however, the human-based services which they support usually terminate in a human. The gap between the human and the computer creates potential for security problems. We examine this gap, as it is manifested in secure Web servers. Felten et al. demonstrated the potential, in 1996, for malicious servers to impersonate honest servers. In this paper, we show how malicious servers can still do this---and can also forge the existence of an SSL session and the contents of the alleged server certificate. We then consider how to systematically
defend
against Web spoofing, by creating a
trusted path
from the browser to the human user. We present potential designs, propose a new one, prototype it in open-source Mozilla, and demonstrate its effectiveness via user studies.
Robot contest as a laboratory for experiential engineering education
Authors: Verner Igor M. , Ahlgren David J.
Published: August 2005

By designing, building, and operating autonomous robots students learn key engineering subjects and develop systems-thinking, problem-solving, and teamwork skills. Such events as the Trinity College Fire-Fighting Home Robot Contest (TCFFHRC) offer rich opportunities for students to apply their skills by requiring design, and implementation of autonomous robots that are tested during competition. Started in 2003, the TCFFHRC Robotics Olympiad offers junior-high and high school students, working alone or in teams, to demonstrate their knowledge by taking a challenging 50-minute written examination in four key areas related to robotics: mechanics, sensors, software, and electronics. The Olympiad comprises a second evaluation medium that supplements a regular contest survey, which has been in place since 1999. The contest survey solicits information about motivation and progress in subject areas from all contest participants--a large and diverse group that includes junior-high and high school students, working engineers, university students, and team supervisors/guides. As a further evaluation step, we have conducted supplementary case studies of courses and curricula at Trinity College and at the Technion. Assessment indicates that the TCFFHRC has achieved its primary goal: to foster and improve robotics education on an international scale.
Is spyware an Internet nuisance or public menace?
Authors: Hu Qing , Dinev Tamara
Published: August 2005

Recent media attention to spyware [2, 5, 7, 8] has brought to light the blunt intrusion into individual privacy and the uncertain hidden cost of free access to Internet sites, along with freeware and shareware. Most spyware programs belong to the more benign category of adware that delivers targeted pop-up ads based on a user's Web surfing habits. The more malicious type of spyware tracks each keystroke of the user and sends that information to its proprietors. Such information could be used for legitimate data mining purposes or it could be abused by others for identity theft and financial crimes.
Web browsing and spyware intrusion
Authors: Shukla Sudhindra , Nah Fiona Fui-Hoon
Published: August 2005

Spyware poses serious privacy and security issues to users of e-commerce and m-commerce [3, 5, 8]. Microsoft claims that half of all computer crashes reported by its customers were caused by spyware and its equivalents. Spyware is also responsible for about 12% of all technical support calls and accounts for the biggest category of customer complaints, according to Dell [1].
How university professors teach project management for information systems
Authors: Reif Harry L. , Mitri Michel
Published: August 2005

Determining where project management education fits into the overall curriculum.
Localization of connexin 30 in the luminal membrane of cells in the distal nephron
Authors: McCulloch Fiona , Chambrey Régine , Eladari Dominique , Peti-Peterdi János
Published: August 2005

Several isoforms of the gap junction protein connexin (Cx) have been identified in a variety of tissues that communicate intercellular signals between adjacent cells. In the kidney, Cx37, Cx40, and Cx43 are localized in the vasculature, glomerulus, and tubular segments in a punctuate pattern, typical of classic gap junction channels. We performed immunohistochemistry in the mouse, rat, and rabbit kidney to study the localization of Cx30 protein, a new member of the Cx family. The vasculature, glomerulus, and proximal nephron segments were devoid of staining in all three species. Unexpectedly, Cx30 was found throughout the luminal membrane of select cells in the distal nephron. Expression of Cx30 was highest in the rat, which also showed some diffuse cytosolic labeling, continuous from the medullary thick ascending limb to the collecting duct system, and with the highest level in the distal convoluted tubule. Labeling in the mouse and rabbit was much less, limited to intercalated cells in the connecting segment and cortical collecting duct, where the apical signal was particularly strong. A high-salt-containing diet and culture medium upregulated Cx30 expression in the rat inner medulla and in M1 cells, respectively. The distinct, continuous labeling of the luminal plasma membrane and upregulation by high salt suggest that Cx30 may function as a hemichannel involved in the regulation of salt reabsorption in the distal nephron.
First to Market: Issue Management Pacesetters and the Pharmaceutical Industry Response to AIDS in Africa
Authors: Dawkins Cedric E.
Published: August 2005

Institutional and resource dependency theories are used to develop a conceptual framework that describes how an “issue pacesetter” affects corporate issue management. The pacesetter model is developed in the following steps: changed stakeholder expectations, pacesetter emergence, heightened attention and pressure, decision making under pressure, and implementation and compliance. The model is then applied to analyze the confrontation between the mainline pharmaceutical industry and AIDS activists and stakeholders over access to AIDS medications in Africa. Analysis of this confrontation demonstrates that issue pacesetters increased the effectiveness of stakeholders in placing institutional pressure on the pharmaceutical industry and contributed to the industry changing its regulations regarding access to AIDS drugs.
Web Sites and Corporate Culture: A Research Note
Authors: Overbeeke Marlies , Snizek William E.
Published: August 2005

This research note examines the feasibility of using corporateWeb sites as an indicator of corporate culture. This is done by comparing theWeb sites of 12 multinational companies in two distinct business sectors—food services and pharmaceuticals—across 23 subdimensions of corporate culture. Differences in the corporate cultures of these companies, as observed in theirWeb sites, are then discussed.
Affecting Adolescence: Scrutinizing the Link between Advertising and Segmentation
Authors: Nairn Agnes , Berthon Pierre
Published: August 2005

The ethical credentials of advertising in regard to young people have been questioned for some time. It is thus intriguing that the same scrutiny has never been directed at the concomitant practice of segmentation. Market segments are usually assumed to exist quite independently of the targeting process and are thus not considered within the same agenda as advertising. But what if advertisers influence the formation of segments? In this postulate, firms are not creating a product for a segment but instead are creating a segment for a product. Advertising and segmentation become interlinked and the ethical concerns expressed over advertising must also be applied to segmentation. The article highlights the link between advertising and segmentation and presents empirical evidence that adolescent attitude/value-based segments can be influenced by advertising. If this result can be generalized, the ethical debate on advertising needs to be widened to include the commercial practice of segmentation.
Life cycle inventory analyses for five waste management options for discarded newspaper
Authors: Dahlbo Helena , Koskela Sirkka , Laukka Jari , Myllymaa Tuuli , Jouttijärvi Timo , Melanen Matti , Tenhunen Jyrki
Published: August 2005

This paper presents the results of life cycle inventory (LCI) analyses that were carried out to determine the environmental impacts (emissions, resource extractions and land use) of different newspaper waste management options for the Helsinki Metropolitan Area (HMA). LCI analyses were performed for five product systems, in which discarded newspapers were divided into two streams: separately collected newspapers and newspapers in mixed waste. In all the options, the manufacturing and printing processes of newspaper were kept unchanged. The waste management alternatives included combinations of material recycling, energy recovery and landfilling. These product systems were modelled using the current collection rate of newspaper and four additional collection rates. The LCIs of the product systems showed that the life cycle phase causing the most environmental impacts was the paper mill. When comparing the different waste management systems, the energy recovery options were in general superior to landfilling. The ecological implications of the increased energy recovery and decreased material recycling of newspaper were, however, not yet considered in the study. These aspects were assessed in the life cycle impact assessment (LCIA), which was performed after the LCI phase.
Use of plastic waste (poly-ethylene terephthalate) in asphalt concrete mixture as aggregate replacement
Authors: Hassani Abolfazl , Ganjidoust Hossein , Maghanaki Amir Abedin
Published: August 2005

One of the environmental issues in most regions of Iran is the large number of bottles made from poly-ethylene terephthalate (PET) deposited in domestic wastes and landfills. Due to the high volume of these bottles, more than 1 million m3 landfill space is needed for disposal every year. The purpose of this experimental study was to investigate the possibility of using PET waste in asphalt concrete mixes as aggregate replacement (Plastiphalt) to reduce the environmental effects of PET disposal. For this purpose the mechanical properties of plastiphalt mixes were compared with control samples. This study focused on the parameters of Marshall stability, flow, Marshall quotient (stability-to-flow ratio) and density. The waste PET used in this study was in the form of granules of about 3 mm diameter which would replace (by volume) a portion of the mineral coarse aggregates of an equal size (2.36-4.75 mm). In all prepared mixes the determined 6.6% optimum bitumen content was used. In this investigation, five different percentages of coarse aggregate replacement were used. The results showed that the aggregate replacement of 20% by volume with PET granules would result in a reduction of 2.8% in bulk compacted mix density. The value of flow in the plastiphalt mix was lower than that of the control samples. The results also showed that when PET was used as partial aggregate replacement, the corresponding Marshall stability and Marshall quotient were almost the same as for the control samples. According to most of specification requirement, these results introduce an asphalt mix that has properties that makes it suitable for practical use and furthermore, the recycling of PET for asphalt concrete roads helps alleviate an environmental problem and saves energy.
The Social Organization of a ‘Stone Fight’
Authors: Poveda David , Marcos Teresa
Published: August 2005

This article examines the sequential organization and social meaning of a ‘stone fight’ between a group of Spanish Gitano children and a group of non-Gitano neighbour children. The episode crystallizes an ongoing dispute between neighbours in the community regarding access and use of public spaces and plazas. The authors argue that this occasion and its surrounding history allows Gitano children to reinterpret and redefine the nature of interethnic relations and contact. Also, it may provide resources for these children to cope with structurally based forms of exclusion and ethnic conflict in other social arenas (such as school or work).
Participatory approaches in urban areas: strengthening civil society or reinforcing the status quo?
Authors: Mitlin Diana , Thompson John
Published: August 2005

The paper examines current experiences with the use of participatory methodologies in low-income urban communities. It outlines the nature and development of participatory approaches and describes experiences, prospects and problems related to their use in an urban context. Three case examples from the UK, Sri Lanka, and India and South Africa demonstrate how innovative approaches are being used by different agencies to strengthen and support the activities of community based organizations. Finally, the paper concludes with a number of broad questions about the future application of participatory approaches in low-income urban communities.
Urban social policy and poverty reduction
Authors: Moser Caroline O.N.
Published: August 2005

The paper describes the differences in the ways that social and economic policy perceive poverty and its underlying causes, and thus differences in how they define it, measure it and institute mechanisms to reduce it. It also highlights the many dimensions of poverty that economic policy ignores and considers the constraints that limit the effectiveness of current poverty reduction strategies.
Rental and rent-free housing as coping mechanisms in La Paz, Bolivia
Authors: Beijaard Frans
Published: August 2005

This paper describes how in La Paz, more than a quarter of all households live rent free in a room, apartment or house with the permission of the owner. This form of tenure is called cedida. The paper also compares how household characteristics vary between owner-occupiers, renters and households in cedida in a sample of consolidated lower-and middle-income neighbourhoods within La Paz. This shows how cedida clearly benefits many younger households, by providing them with an opportunity to live in or near the city centre which would be beyond their means as renters or owners.
Parallel activities at Habitat II and the H@bit@t University: a call for takers
Authors: Garau Pietro
Published: August 2005

Habitat II includes not only the official UN Conference on Human Settlements but a great range of other events organized by NGOs, research and professional associations and other UN agencies. These are outlined below, including the H@bit@t University which is the name given to a series of global, informal and open-ended events to be organized as part of the Habitat II Conference.
Civic engagement in creating future cities
Authors: Korten David C.
Published: August 2005

This paper describes how most global U.N. Conferences have failed to address the causes of the problems they are discussing -especially the inappropriate institutional framework where the imperatives of the “money world” take precedence over the living world of people and where control over productive resources is increasaingly wrested away from local people and communities (and governments) by large and generally unaccountable corporations. It also describes the routes to a more just and sustainable society, and how civic society must reclaim the power it is losing to the money world. This includes the ways in which the United Nations Habitat II Conference can and should align itself with this process.
Our city, our future: towards sustainable development in European cities
Authors: Mega Voula
Published: August 2005

This paper looks at the trends in the urban Euroscape and puts in perspective some innovative projects identified in Europe conducive to (and necessary for) sustainable cities. Most of the projects come from a European overview of urban innovations(1) undertaken by the European Foundation for the Improvement of Living and Working Conditions.((2)The overview focused on projects with a collective purpose, with significance for a city, projects resisting time and favouring local democracy and participation at the conception, decision and executive phases, projects introducing new ecological materials, techniques, methods and conditions and, last but not least, projects that produce culture and are cultural products.(3)
Urban poverty and the informal economy in South Africa's economic heartland
Authors: Rogerson Christian M.
Published: August 2005

The paper describes urban poverty and the informal economy in the economic hub of South Africa, the Pretoria-Witwatersrand-Vereeniging region (which includes Johannesburg). Its findings show the limited possibilities for using the informal economy as a means of resolving pressing issues of poverty in South Africa's cities. After an introduction about the post-apartheid government's Reconstruction and Development Programme, the paper describes the scale and nature of urban poverty and the causes of its growth and the growth and changing complexion of the informal economy, including the rapid growth of “survivalist” enterprises and the links between the formal and informal economy. This includes a consideration of what constrains the informal economy and the links between supporting the informal economy and addressing poverty.
Tunis city in transition
Authors: Stambouli Fredj
Published: August 2005

This paper describes the transformation of the city of Tunis during the last 50 years, indicating in particular how the city has moved from an ex-colonial and rather provincial city into a large metropolis that is open to and influenced by the financial flows of international capitalism and that is seeking further integration into the world economy. It also describes how housing has evolved during this same period, especially housing for low-income groups which is considered a key test for understanding the social and political dimensions of this transformation. By considering the housing problems and the difficulties of integrating the low-income majority of the population we can identify the deep changes in the context and profile of the city population as well as the rupture that has occurred in the urban fabric in terms of its form and structure.
Inequality and health in the metropolitan area of Buenos Aires
Authors: Arrossi Silvina
Published: August 2005

This paper describes differences in unsatisfied basic needs and in mortality rates by age group for the 20 districts which make up the Metropolitan Area of Buenos Aires. It also describes differences in causes of death by age group between the central city (Capital Federal) and the inner and outer ring of municipalities that surround it. The paper ends with a discussion of why it is important to develop a more detailed statistical picture of health differences between districts in cities and examines also the difficulties in doing so.
Social and economic imbalances in the metropolitan area of Monterrey
Authors: Garza Gustavo
Published: August 2005

The paper describes social and economic differences between Monterrey’s eight municipalities, including housing conditions and basic service provision, and how these changed between 1970 and 1990. It also describes the social and economic differences for 1990 between the 710 micro-areas into which Monterrey was divided, which allows a more precise and detailed picture of intra-urban inequalities. It also reveals the limitations of an intra-urban analysis based on municipal boundaries by showing many clusters of micro-areas with very low levels of socio-economic development in some of the better off municipalities.
Urban inequalities in mental health: the case of São Paulo, Brazil
Authors: Blue Ilona
Published: August 2005

This paper describes how the number of people suffering from mental ill-health has been under-estimated in urban areas in Africa, Asia and Latin America. It also explains how the complex range of factors that contribute to mental ill-health, and the ways in which they interact, remain poorly understood. It then describes the findings from research on mental health in three sub-districts of São Paulo City: one with relatively poor quality housing and low-income households, one predominantly middle-class with better housing and one with high-class housing and high average incomes.
A decision support system for architects based on participatory tools for community design
Authors: Dasgupta Shubhagato
Published: August 2005

Many participatory tools and methods have focused on rural development but few have considered aspects of settlement in rural areas. This paper explores a number of such tools designed for Indian professionals working in the field of housing. The author first discusses a number of elements related to the effective participation of local residents and then describes the tools themselves.
The environmental impacts and public costs of unguided informal settlement; the case of Montego Bay
Authors: Ferguson Bruce
Published: August 2005

The development of squatter and other informal settlements in Montego Bay (Jamaica) helps individual low-income households (although not the poorest) solve their shelter problem. However, informal settlement also exacts tremendous costs to neighbourhoods and the city as a whole, largely in the form of environmental problems that threaten household health and the region’s main economic base, the tourist trade. These environmental costs come in the form of inadequate or no provision for paved roads, piped water, sanitation, and garbage for a high proportion of those living in informal settlements. When these costs are taken into account, informal settlement is no less expensive than formal-sector development. The paper quantifies the costs of providing infrastructure to unguided informal settlement (squatter upgrading) and shows them as comparable to those for government-produced serviced sites and privately produced moderate-income projects - and the infrastructure is often of poorer quality and with less possibility for cost recovery. The paper ends with a discussion of policies that can help solve this problem. Instead of reacting to land invasions, governments should get ahead of low-income housing demand by guiding the development of informal settlements and by lowering the cost of formalsector production. This strategy promises higher quality housing and infrastructure, lower costs and fewer environmental problems.
On popular participation in a culture of patronage; patrons and grassroots organization in a sites and services project in Hyderabad, Pakistan
Authors: van der Linden Jan
Published: August 2005

This paper begins by discussing the ways in which patronage inhibits housing solutions for low-income groups and the conditions under which it has greatest scope for operating. There follows a discussion of what factors diminish the power of patronage within the context of a government-run site and service programme in Hyderabad (Pakistan). Here, reducing scarcity (in this case affordable land sites) and the distance between people and government were important in reducing (although not removing) the role of patrons. The paper ends with some suggestions as to how the role of patrons can be reduced in government projects - and how low-income households' direct access to land and basic services without the involvement of a patron are among the best forms of “participation”.

“If you live in the river, it is better to stay friends with the crocodile” (Pakistani proverb).
Community participation in the management of the urban environment in Rufisque (Senegal)
Authors: Gaye Malick , Diallo Fodé
Published: August 2005

This paper describes how problems of inadequate provision for water, sanitation, drainage and the collection and disposal of garbage were tackled in nine low-income communities in Rufisque, Senegal. This was done largely by the inhabitants themselves but in partnership with an NGO (ENDA-Tiers Monde), with local authorities and with support from other agencies. The paper emphasizes how the approach taken - with local problems addressed by local groups working together with technologies they control and with environmental goals integrated from the outset - is one that is far more appropriate to Africa's urban problems. The paper also discusses how these works were funded including how the need for external funding was kept down and the role of a revolving fund.
Low-income rental housing: are South African cities different?
Authors: Gilbert Alan , Mabin Alan , Mc Carthy Malcolm , Watson Vanessa
Published: August 2005

A significant proportion of the black urban population in South Africa rent accommodation. Surveys conducted in two low-income settlements in Cape Town and Johannesburg show that the rental housing scene is in many ways similar to that found in other Third World cities. Landlords are older than their tenants, many are female, their families are larger, their homes have more space and better services. Few landlords make any money and landlord-tenant relationships are not generally conflictive. At the same time, rental conditions in the survey settlements appear to be very different from those found in most other poor cities. Most significant is that few South African landlords build accommodation; the majority merely offer space to tenants who build their own shacks. The poor quality of accommodation helps keep rents low which in turn accentuates the feeling that is it not worth investing in rental accommodation. Few landlords actively seek out tenants, most grant space in the backyard only out of compassion. Further research is investigating whether more typical forms of rental housing exist in Cape Town and Johannesburg. The project also seeks to persuade the South African government that it should develop some kind of rental housing policy.
Developing financial services for the urban poor: the Sharan experience
Authors: Titus Mathew
Published: August 2005

Mobilizing, promoting and operating self-help groups that provide financial services is a difficult and costly learning cycle for each NGO. These early difficulties are, however, resources for skills, methods and insights that are intrinsic to both working with communities of the poor and providing financial services. Transforming the experience into a systematic training process for newer entrants into the arena is an important constituent of attempting to reduce learning time and costs. This document from the field looks closely at some of the issues as experienced by Sharan, an NGO based in Delhi of developing community based financial services for the urban poor.
Spaces for the children of the urban poor: experiences with participatory action research (PAR)
Authors: Nieuwenhuys Olga
Published: August 2005

This paper explains why participatory action research (PAR) could be so important in helping the children of the urban poor, and those who work with them, generate relevant insights into their specific needs and priorities and help them influence decisions that are taken about their lives. The paper begins by discussing the problems facing children in urban areas of the South and why more participatory research approaches which work with children have come to the fore. It then describes what participatory action research is (and is not) and why researchers and the institutions that fund them have difficulty in supporting such a research approach, especially in relation to children. The paper then addresses the three main implications for researchers who want to use PAR with children: taking responsibility for the children’s needs and priorities within the research; balancing participation and mediation; and ensuring the research helps to negotiate more spaces for children in their environment and more power in their relationship with the state and society.