Brief Overview (brief + overview)

Distribution by Scientific Domains
Distribution within Medical Sciences

Selected Abstracts

Brief Overview of BioMicroNano Technologies

Paul L. Gourley
This paper provides a brief overview of the fields of biological micro-electromechanical systems (bioMEMs) and associated nanobiotechnologies, collectively denoted as BioMicroNano. Although they are developing at a very rapid pace and still redefining themselves, several stabilized areas of research and development can be identified. Six major areas are delineated, and specific examples are discussed and illustrated. Various applications of the technologies are noted, and potential market sizes are compared. [source]

PASSing the provenance challenge

David A. Holland
Abstract Provenance-aware storage systems (PASS) are a new class of storage system treating provenance as a first-class object, providing automatic collection, storage, and management of provenance as well as query capabilities. We developed the first PASS prototype between 2005 and 2006, targeting scientific end users. Prior to undertaking the provenance challenge, we had focused on provenance collection and storage, without much emphasis on a query model or language. The challenge forced us to (quickly) develop a query model and infrastructure implementing this model. We present a brief overview of the PASS prototype and a discussion of the evolution of the query model that we developed for the challenge. Copyright © 2007 John Wiley & Sons, Ltd. [source]

Bowen systems theory and mediation

Wayne Regina
The field of mediation is largely technique- and process-driven. In an effort to develop a more comprehensive theoretical system for mediation, this article applies Bowen Systems Theory to mediation. The article begins with a brief overview of the development of Bowen Systems Theory; it proceeds to define its central concepts, including differentiation, triangulation, and chronic anxiety; finally, the article applies these concepts to mediation and discusses the relationship between theory and technique, using caucusing and co-mediation as examples. The article concludes that Bowen Systems Theory naturally extends to mediation, providing this field with a comprehensive theoretical system. [source]

Computer-related skin diseases

Marjolein Wintzen
The use of computers has increased vastly, occupationally as well as for private use, and in the last decade, a number of reports have been published in which skin problems are ascribed to the (intensive) use of computers. Not only irritant or mechanically induced contact dermatitis has been reported but also allergic contact dermatitis. As this appears to be a new group of occupational dermatoses, we present a brief overview of these cases, and aetiologic factors are discussed. [source]

When business associations and a federal ministry jointly consult civil society: a CSR policy case study on the development of the CSR Austria Guiding Vision

Astrid Konrad
Abstract In 2002, Austrian business organizations and the Austrian Federal Ministry of Economics and Labour decided to raise the awareness of CSR in Austria by formulating a CSR guiding vision for Austrian businesses after consulting a broad variety of stakeholders. This paper describes the development of the ,CSR Austria Guiding Vision' from 2003, and it gives a brief overview of other public CSR initiatives launched in Austria since then. Since the authors were involved drafting the CSR Austria Guiding Vision as consultants, the paper describes success factors, lessons learned and recommendations relevant for other large-scale stakeholder dialogues on CSR from an insider perspective. Overall, we conclude that a clear idea about the structure, the type and the rules of the stakeholder involvement (conceptual issues), in combination with a timely, honest and empathic approach towards stakeholders (procedural issues), are important success factors for any stakeholder dialogue. Copyright © 2007 John Wiley & Sons, Ltd and ERP Environment. [source]

Decision Sciences Research in China: A Critical Review and Research Agenda,Foundations and Overview,

Xiande Zhao
ABSTRACT This article focuses on decision sciences research in China, providing an overview of current research and developing a foundation for future China-based research. China provides a unique research opportunity for decision sciences researchers, owing to its recent history, rapid economic development, and strong national culture. We examine recent economic reforms and their impact on the development of research questions in the decision sciences, as well as discuss characteristics of the diverse regions in China and their potential as sites for various types of research. We provide a brief overview of recent China-based research on decision sciences issues relating to national culture, supply chain management, quality management, production planning and control, operations strategy, and new product development and discuss some of the unique methodological challenges inherent in China-based research. We conclude by looking forward to emerging research opportunities in China. [source]


ABSTRACT This module will introduce you to the ethical concepts underlying applied ethical decision-making in the area of research involving human participants. We will also learn what the issues are that people involved in research on research ethics are concerned with. Ethics without an understanding of historical and legal context makes arguably little sense. It is for this reason that this module will begin with a brief history of research ethics and ends with a brief overview of the relevant national and international guidelines pertaining to ethical issues in research involving human participants. [source]

Evolving Themes in Rural Development 1950s-2000s

Frank Ellis
This article provides a brief overview of the major switches in rural development thinking that have occurred over the past half-century or so. Dominant and subsidiary themes are identified, as well as the co-existence of different narratives running in parallel. The continuing success of the long-running ,small-farm efficiency' paradigm is highlighted. The article concludes by asking whether sustainable livelihoods approaches can be interpreted as providing a new or different way forward for rural development in the future. The answer is a cautious ,yes', since these approaches potentially permit the cross-sectoral and multi-occupational character of contemporary rural livelihoods in low-income countries to be placed centre-stage in efforts to reduce rural poverty. [source]

Preconditioning and postconditioning: new strategies for cardioprotection

D. J. Hausenloy
Despite optimal therapy, the morbidity and mortality of coronary heart disease (CHD) remains significant, particularly in patients with diabetes or the metabolic syndrome. New strategies for cardioprotection are therefore required to improve the clinical outcomes in patients with CHD. Ischaemic preconditioning (IPC) as a cardioprotective strategy has not fulfilled it clinical potential, primarily because of the need to intervene before the index ischaemic event, which is impossible to predict in patients presenting with an acute myocardial infarction (AMI). However, emerging studies suggest that IPC-induced protection is mediated in part by signalling transduction pathways recruited at time of myocardial reperfusion, creating the possibility of harnessing its cardioprotective potential by intervening at time of reperfusion. In this regard, the recently described phenomenon of ischaemic postconditioning (IPost) has attracted great interest, particularly as it represents an intervention, which can be applied at time of myocardial reperfusion for patients presenting with an AMI. Interestingly, the signal transduction pathways, which underlie its protection, are similar to those recruited by IPC, creating a potential common cardioprotective pathway, which can be recruited at time of myocardial reperfusion, through the use of appropriate pharmacological agents given as adjuvant therapy to current myocardial reperfusion strategies such as thrombolysis and primary percutaneous coronary intervention for patients presenting with an AMI. This article provides a brief overview of IPC and IPost and describes the common signal transduction pathway they both appear to recruit at time of myocardial reperfusion, the pharmacological manipulation of which has the potential to generate new strategies for cardioprotection. [source]

Procedural learning and dyslexia

DYSLEXIA, Issue 3 2010
R. I. Nicolson
Abstract Three major ,neural systems', specialized for different types of information processing, are the sensory, declarative, and procedural systems. It has been proposed (Trends Neurosci.,30(4), 135,141) that dyslexia may be attributable to impaired function in the procedural system together with intact declarative function. We provide a brief overview of the increasing evidence relating to the hypothesis, noting that the framework involves two main claims: first that ,neural systems' provides a productive level of description avoiding the underspecificity of cognitive descriptions and the overspecificity of brain structural accounts; and second that a distinctive feature of procedural learning is its extended time course, covering from minutes to months. In this article, we focus on the second claim. Three studies,speeded single word reading, long-term response learning, and overnight skill consolidation,are reviewed which together provide clear evidence of difficulties in procedural learning for individuals with dyslexia, even when the tasks are outside the literacy domain. The educational implications of the results are then discussed, and in particular the potential difficulties that impaired overnight procedural consolidation would entail. It is proposed that response to intervention could be better predicted if diagnostic tests on the different forms of learning were first undertaken. Copyright © 2010 John Wiley & Sons, Ltd. [source]

Advanced Opportunities for Student Education in Emergency Medicine

Charissa B. Pacella MD
Abstract Many medical students are excited about emergency medicine (EM) following a standard clerkship and seek out additional learning opportunities. An advanced EM elective may accomplish several educational goals, including development of clinical skills in evaluating the undifferentiated patient, broader exploration of the field of EM, and more focused study of one particular aspect of EM. Previously cited examples include pediatric EM, medical toxicology, occupational medicine, sports medicine, and EM research. Numerous other EM specialty courses for senior medical students are emerging, as reflected in the "Undergraduate Rotations" listings on the Society for Academic Emergency Medicine. A few examples drawn from the list include emergency ultrasound, international EM, wilderness medicine, disaster medicine, geriatric EM, and hyperbaric medicine. Educators aspiring to develop, or in the process of developing, an advanced EM elective may benefit from a brief overview of necessary course considerations, including didactic format, the clinical role of the medical student in the emergency department, and involvement with patient procedures. Suggestions are made regarding additional educational opportunities, including follow-up of patients seen in the emergency department and development of an emergency department radiology case file. This article also addresses several related concerns, including suggested prerequisites, administration and cost considerations, appropriate didactic topics, and methods for evaluating students. Several EM subspecialty areas, namely pediatric EM, medical toxicology, and out-of-hospital care, are specifically discussed. Formal advanced cardiac life support training is also often included in an advanced EM elective and is briefly discussed. The overall intent of this article is to provide medical student educators with resources and ideas to assist them in developing a unique advanced EM elective. [source]

A brief overview of mechanisms of mitochondrial toxicity from NRTIs,

James J. Kohler
Abstract Nucleoside reverse transcriptase inhibitors (NRTIs) in combinations with other antiretrovirals (highly active antiretroviral therapy, HAART) are the cornerstones of AIDS therapy, turning HIV infection into a manageable clinical entity. Despite the initial positive impact of NRTIs, therapeutic experience revealed serious side effects that appeared to originate in the mitochondria and which ultimately manifested as dysfunction of that organelle. It may be reasonable to consider that as the AIDS epidemic continues and as survival with HIV infection is prolonged by treatment with HAART, long-term side effects of NRTIs may become increasingly common. This consideration may be underscored in children who are born to HIV-infected mothers who received NRTI therapy in utero during gestation. The long-term effect of that NRTI exposure in utero is not clear yet. This review examines some proposed mechanisms of NRTI mitochondrial toxicity, including genetic predisposition, defects in mitochondria DNA replication, the encompassing "DNA pol-, hypothesis," the relationship between mitochondrial nucleotide and NRTI pools, mitochondrial DNA mutation and dysfunction, and oxidative stresses related to HIV infection and NRTIs. Mechanisms of mitochondrial toxicity are reviewed with respect to key cell biological, pathological, and pharmacological events. Environ. Mol. Mutagen., 2006. © 2006 Wiley-Liss, Inc. [source]

America's Health Care Safety Net Intact or Unraveling?

Lynne D. Richardson MD
Abstract In virtually every community in this nation, the emergency department (ED) is an integral part of the health care safety net, often serving as the only available point of access to the health care system for many vulnerable and disenfranchised individuals. The authors present a brief overview of the March 2000 report released by the Institute of Medicine that described and assessed the current status of the nation's health care safety net. The authors discuss the role of the ED as a safety net provider and as a window onto the status of the rest of the health care system. The authors describe the Andersen behavioral model of health services use and suggest it as a useful theoretical framework for emergency medicine researchers who are interested in studying these issues. [source]


Matthew J. Sullivan
The use of Psychologist Parent Coordinators in child custody cases (called Special Masters in California) is becoming increasingly prevalent across the country. This postdivorce parenting coordination role is a legal/psychological hybrid, demanding knowledge and skill in legal domains (legal procedure, relevant case law, etc.), psychological domains (child development, family systems, etc.), and dispute resolution (mediation and settlement processes). Situated in the interface of legal and psychological paradigms, Parent Coordination may be reviewed by multiple legal and psychological regulatory bodies. Coming from varying perspectives, the practice guidelines and mandates of these legal, ethical, and licensing agencies impose multiple standards of review of Parent Coordination. A brief overview of the legal and psychological review processes applicable to Special Master work in California, as they relate to common issues that confront the Parenting Coordinator across the country, is the focus of this article. They suggest that the current lack of coordination of review processes creates a minefield of professional risk for the psychologist who chooses to practice in this role. [source]

Sociopolitical Activist or Conversational Partner?

FAMILY PROCESS, Issue 1 2003
Collaborative Therapies, Distinguishing the Position of the Therapist in Narrative
In this article, we explore the similarities and differences of two contemporary family therapy approaches: narrative and collaborative therapies. These therapies are contrasted by describing positioning of the narrative practitioner as sociopolitical activist and the collaborative practitioner as conversational partner. The article begins with a brief overview of the two therapies. Subsequently, we outline their epistemological genealogies and the practice similarities that arise from the theoretical assumptions underpinning these therapies. The remainder of the article addresses the theoretical and therapeutic differences in narrative and collaborative approaches reflected in the positioning of therapist as either sociopolitical activist or conversational partner. While narrative and collaborative approaches share more similarities than differences in relation to their emphasis on the constitutive characteristics of language, focus on socio,elational contexts, and critique of singular objective truths, prominence is given to the starker contrasts in narrative and collaborative understandings of politics, power, dialogue, and discourse. It is proposed that by outlining some provocative contrasts between narrative and collaborative approaches, new conversations and generative practices will emerge in the therapy room. [source]

Organically Functionalized Mesoporous Silica by Co-structure-Directing Route

Chuanbo Gao
Abstract This article provides a brief overview of functional mesoporous silica materials synthesized by the co-structure-directing route, which is distinct from conventional synthesis strategies. In these systems, organosilane serves as the co-structure-directing agent (CSDA), which provides critical interactions between the template and organic part of the organosilane to form mesostructures, thus retaining the organic groups on the pore surface after removal of the template by extraction. i) The formation of anionic-surfactant-templated mesoporous silicas (AMSs) has been achieved by the co-structure-directing route, which leads to a variety of mesostructures, porous properties and morphologies. ii) Other co-structure-directing systems for synthesizing mesoporous silicas have also been achieved, including systems using cationic surfactants and non-surfactants, and systems using DNA for constructing nanofibers and DNA,silica liquid crystalline complexes. iii) Evidence for the regular arrangement of functional groups on the pore surface resulted from the co-structure-directing effect has been discussed. Also included is a brief description of the application, future requirements, and trends in the development of mesoporous materials by the co-structure-directing route. [source]

Status of search for supersymmetry

S. Bethke
A brief overview of the current status and of future perspectives of searches for Supersymmetry is given. [source]

Freshwater and marine virioplankton: a brief overview of commonalities and differences

Summary 1. Viruses are a pervasive component of microbial food webs in both marine and freshwater systems. The abundance of viruses in individual aquatic systems appears to be independent of salinity but related to the biomass of primary and secondary producers as well as seasonal effects. Burst size, virus production rate and the percentage of microbial cells carrying a viral burden also appear to be more closely correlated to trophic status than to salinity. 2. In marine environments, the roles of planktonic viruses as regulators of carbon and nutrient cycling as well as microbial community structure have been a focus of numerous studies, yet the roles of freshwater virioplankton remain much less studied. Nevertheless, a survey of published freshwater studies demonstrates that virioplankton recycle important quantities of growth-limiting nutrients from hosts via generation of dead particulate and dissolved organic matter during cell lysis, and suggests that both the chemical speciation and concentration of these organic compounds and nutrients may have important influences on the microbial community. 3. Parallel observations on the spatial patterns and dynamics of microbial mortality due to viruses or grazing are more advanced in freshwaters than in marine environments. However, the constraints that determine whether virus- or grazer-mediated mortality dominates are not yet understood in either environment. 4. Application of molecular approaches has facilitated the examination of the diversity and ecological dynamics of specific viral populations and entire communities. The depth of detail achieved in marine environments towards characterizing these populations and communities is just beginning to be matched in freshwater systems. The few available data suggest that viruses targeting-related hosts in freshwater and marine systems may be genetically distinct. 5. Although the role of viruses in aquatic systems is complex and remains insufficiently studied, our survey of the literature indicates that, despite some differences, many of the controls on virioplankton activity and diversity are similar in marine and freshwater environments. [source]

The Eastern Congo,a beauty spot, rediscovered from a geological point of view

GEOLOGY TODAY, Issue 2 2010
F.U. Bauer
In East Africa, the feedback between tectonic uplift, erosional denudation and associated possible climate changes is being studied by a multidisciplinary research group, ,Riftlink'. The group's focus is the Albertine Rift, the northern part of the western branch of the East African Rift System, and in particular the rising Rwenzori Mountains that stretch along the border of the D.R. Congo and Uganda. Major questions relate to the timing of the formation of the Rwenzori Mountains, and whether the height of these mountains (> 5000 m) relates to rift movements in Neogene times, or represents an old basement block that formed a topographic high long before. Though, at first, research concentrated on the eastern (Ugandan) part of the Albertine Rift and Rwenzori Mountains, it has now moved further to the west to the D.R. Congo. A first field-campaign, covering the area from northern Lake Edward along the rift shoulder up to the Blue Mountains at Lake Albert, was conducted in summer 2009, in cooperation with the Ruwenzori State University of Butembo. Here, we present a brief overview of the field-campaign, with impressions gathered on the morphology and geology of the study area. [source]

The Mystery of Feilenhauer Torgelow: Fontane's Elusive Social Democrat

Scott Tatchell
As Günter Grass (among others) has highlighted, Theodor Fontane's Der Stechlin is one of the first German novels to feature a social-democratic politician. This article examines the character of Torgelow, who is elected to the Reichstag. Anything we learn about Torgelow is always at one remove, by way of other characters. He never features directly in the narrative, and remains a mysterious figure. After summarising the political backdrop against which the novel is set and providing a brief overview of Fontane's own attitude to the SPD, the article argues that pragmatic concerns and Fontane's burgeoning interest in the party combine to explain Torgelow's inclusion. Subsequently, Torgelow's abstract characterisation is explained as a consequence of Fontane's desire to portray the fear, loathing and ignorance inherent in bourgeois and aristocratic attitudes towards the party. The argument that Torgelow is a mere cipher for the party is rejected. Instead, Torgelow should be seen in the wider context of Fontane's depiction of the SPD as a whole. Overall, the article argues that the character of Torgelow provides a means for Fontane to acknowledge the SPD's rise, to suggest that its predominance will be of finite duration, and to oppose the party's persecution. [source]

N,N -Dimethylformamide as a Reaction Medium for Metal Nanoparticle Synthesis

Isabel Pastoriza-Santos
Abstract The versatility of wet chemical methods has rendered them extremely popular for the preparation of metal nanoparticles with tailored size and shape. This Feature Article reviews the use of N,N -dimethylformamide (DMF) for the reduction of metal salts, mainly Au and Ag, while also acting as a solvent. Apart from describing the ability of DMF to reduce metal salts, the effect of different parameters, such as the concentration of capping agent and metal precursors, the presence of preformed seeds acting as catalysts or their crystalline structure, on particle morphology are analyzed. Published reports on the use of different capping agents are summarized, with particular emphasis on the role of poly(vinylpyrrolidone) to determine the morphology of the particles. Finally, a brief overview is provided on the modulation of the optical response in DMF-based metal nanoparticle colloids with tunable size and shape. [source]

E-commerce, Transportation, and Economic Geography

William P. Anderson
ABSTRACT This paper explores possible ways in which growth in Internet retailing (e-retailing) may affect the spatial distribution of economic activities. After a brief overview of e-retailing, a categorization of possible spatial impacts is introduced. These include impacts on the retail industry, such as substitution of e-retail for brick-and-mortar retail, impacts on transportation, such as substitution of freight transportation for personal transportation in goods delivery, and pervasive impacts that affect the whole economy. The latter category includes uniform delivered pricing, spatial leveling of accessibility, and marketing strategies that target individuals rather than regions. The question of whether e-retailing and brick-and-mortar retailing are truly substitutes is taken up in the next section, along with potential implications of multi-channel retailing. The final section of the paper defines some critical research directions. [source]

Local Electrochemical Functionality in Energy Storage Materials and Devices by Scanning Probe Microscopies: Status and Perspectives

Sergei V. Kalinin
Abstract Energy storage and conversion systems are an integral component of emerging green technologies, including mobile electronic devices, automotive, and storage components of solar and wind energy economics. Despite the rapidly expanding manufacturing capabilities and wealth of phenomenological information on the macroscopic device behaviors, the microscopic mechanisms underpinning battery and fuel cell operations in the nanometer,micrometer range are virtually unknown. This lack of information is due to the dearth of experimental techniques capable of addressing elementary mechanisms involved in battery operation, including electronic and ion transport, vacancy injection, and interfacial reactions, on the nanometer scale. In this article, a brief overview of scanning probe microscopy (SPM) methods addressing nanoscale electrochemical functionalities is provided and compared with macroscopic electrochemical methods. Future applications of emergent SPM methods, including near field optical, electromechanical, microwave, and thermal probes and combined SPM-(S)TEM (scanning transmission electron microscopy) methods in energy storage and conversion materials are discussed. [source]

Recent Progress on Silica Coating of Nanoparticles and Related Nanomaterials

Andrés Guerrero-Martínez
Abstract In recent years, new strategies for silica coating of inorganic nanoparticles and organic nanomaterials, which differ from the classical methodologies, have emerged at the forefront of materials science. Silica as a coating material promises an unparalleled opportunity for enhancement of colloidal properties and functions by using core,shell rational designs and profiting from its synthetic versatility. This contribution provides a brief overview of recent progress in the synthesis of silica-coated nanomaterials and their significant impact in different areas such as spectroscopy, magnetism, catalysis, and biology. [source]

The Historiography of the English State during ,the Long Eighteenth Century': Part I , Decentralized Perspectives

Simon Devereaux
This article reviews the four most prominent themes in the historiography of the modern English state during the last six decades, with a particular focus on ,the long eighteenth century' (1660,1837). The first is the vision of an expansive and centralized administrative state in Victorian England most famously set forth in the work of the late Oliver MacDonagh. Second is the notion of the state as an information-gathering entity that has recently been forcefully stated by Edward Higgs. Third is the vision of an unexpectedly powerful, substantially centralized ,fiscal-military' state during the eighteenth century, powerfully evoked in the work of John Brewer. Finally, a brief overview is given of the prodigious historical literature that has arisen in recent years surrounding the notion of the state as abstract entity capable of commanding the loyalties of those people over whom it rules. The article concludes by suggesting how a more fully integrated vision of the English state in history might be achieved through a deeper, more dynamic interrelation of changing political-administrative structures and shifting social-cultural forces. [source]

The Experimental Appraisal Instrument: A brief overview

Ash M. Genaidy
Background Recently, there has been a great influx in experimental research to assess the health effects of nanoparticles/materials/fibers. Currently, there is no structured methodology to assess the methodological quality of the reported studies. Objective This article reports an experimental appraisal instrument with the goal to critically assess experimental studies. Methods A search of electronic databases was conducted to examine prior work on the subject and to extract the components of such an instrument. Results The electronic search revealed no major instrument designed to evaluate experimental strategies on health effects of nanoparticles/materials/fibers. An experimental appraisal instrument was developed and was patterned after the Epidemiological Appraisal Instrument reported by Genaidy and LeMasters (2006). Conclusions The validity and reliability of such an instrument will be reported in future work. © 2008 Wiley Periodicals, Inc. [source]

Testing Community Empowerment Strategies in Zimbabwe: Examples from Nutrition Supplementation, and Water Supply and Sanitation Programmes

IDS BULLETIN, Issue 1 2000
Mungai Lenneiye
Summary This article provides a brief overview and examples of how communities were involved in feeding programmes during years of drought in Zimbabwe, and in the management of rural water supply and sanitation programmes throughout the 1980s. The balance between political and technical demands in the implementation of these programmes indicates that they started off with community interests at the centre, but gradually gave way to the needs of the bureaucracy (both political and administrative). The main lessons to be learnt from these programmes is that information on entitlements and obligations (on the part of communities and external agencies) is a prerequisite for successful community development projects. Furthermore, the extent of accountability to communities is directly proportional to progress made towards the devolution of power to democratic development structures, be they directly or indirectly elected. [source]

One-Dimensional Conducting Polymer Nanostructures: Bulk Synthesis and Applications

ADVANCED MATERIALS, Issue 14-15 2009
Henry D. Tran
Abstract This Progress Report provides a brief overview of current research activities in the field of one-dimensional (1D) conducting polymer nanostructures. The synthesis, properties, and applications of these materials are outlined with a strong emphasis on recent literature examples. Chemical methods that can produce 1D nanostructures in bulk quantities are discussed in the context of two different strategies: 1) procedures that rely on a nanoscale template or additive not inherent to the polymer and 2) those that do not. The different sub-classifications of these two strategies are delineated and the virtues and vices of each area are discussed. Following this discussion is an outline of the properties and applications of 1D conducting polymer nanostructures. This section focuses on applications in which nanostructured conducting polymers are clearly advantageous over their conventional counterparts. We conclude with our perspective on the main challenges and future research directions for this new class of nanomaterials. This Progress Report is not intended as a comprehensive review of the field, but rather a summary of select contributions that we feel will provide the reader with a strong basis for further investigation into this fast emerging field. [source]

Bifurcation and instability modelling by a multimechanism elasto-plastic model

Kamel Hamadi
Abstract The bifurcation and instability conditions in geomechanics are closely related to the elasto-plastic behaviour. In this paper the potential of a multimechanism elasto-plastic model to predict various modes of failure is examined. First, a brief overview for the essential aspects of the constitutive model and the development of the elasto-plastic constitutive matrix for this model are presented. Then, numerical simulations of different drained and undrained paths in the axisymmetric and plane-strain conditions for the Hostun sand are illustrated. These examples confirm the capacity of the model to reproduce instability and strain localization phenomena. The obtained response is in agreement with experimental observations, theoretical developments and numerical analyses existing in the literature. Copyright © 2007 John Wiley & Sons, Ltd. [source]

Elicited imitation:a brief overview

Thora Vinther
This article considers the key concepts of elicited imitation (EI), with the aim of contributing to the understanding of this technique for language testing. EI has been widely debated and often criticized, but there seems now to be an agreement as to its usefulness, as long as it is applied with great care. The article reviews the literature on EI and suggests some issues for discussion, such as the process of imitating, the length and structure of the stimulus, contextual support, whether the test evaluates comprehension or production skills, whether it assesses imitative or spontaneous language capacity, and how scoring is carried out. Although the focus is on foreign language acquisition (FLA), studies about EI within other areas have been included where this is considered useful for the understanding of the technique. [source]