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Terms modified by Accessible Selected AbstractsTHE FACE OF MONEY: Currency, Crisis, and Remediation in Post-Suharto IndonesiaCULTURAL ANTHROPOLOGY, Issue 1 2009KAREN STRASSLER ABSTRACT In the period of transition following Suharto's resignation as president of Indonesia in 1998, the image of the 50,000Rp bill bearing his face became a visual shorthand for the corruption and abuse of power that had characterized his regime. Accessible, decentralized consumer technologies enabled people to alter money's appearance, transforming it from a fetish of the state into a malleable surface available for popular reinscription. As the medium of money was "remediated",absorbed into other media, refashioned, and circulated along new pathways,it became a means by which people engaged questions of state power, national integrity, political authenticity, and economic relations opened up by the crisis of Reformasi (Reform). The essay argues that remediations of public forms play a crucial role in times of political transition by enabling people to materialize alternative visions of political authority and authenticity. Moreover, remediated forms have become a characteristic modality of political communication in the post-Suharto period under conditions of democratization and an increasingly diversified media ecology. [source] Life-Satisfaction Is a Momentary Judgment and a Stable Personality Characteristic: The Use of Chronically Accessible and Stable SourcesJOURNAL OF PERSONALITY, Issue 3 2002Ulrich Schimmack ABSTRACT Social cognition research indicates that life-satisfaction judgments are based on a selected set of relevant information that is accessible at the time of the life-satisfaction judgment. Personality research indicates that life-satisfaction judgments are quite stable over extended periods of time and predicted by personality traits. The present article integrates these two research traditions. We propose that people rely on the same sources to form repeated life-satisfaction judgments over time. Some of these sources (e.g., memories of emotional experiences, academic performance) provide stable information that explains the stability in life-satisfaction judgments. Second, we propose that the influence of personality traits on life satisfaction is mediated by the use of chronically accessible sources because traits produce stability of these sources. Most important, the influence of extraversion and neuroticism is mediated by use of memories of past emotional experiences. To test this model, participants repeatedly judged life-satisfaction over the course of a semester. After each assessment, participants reported sources that they used for these judgments. Changes in reported sources were related to changes in life-satisfaction judgments. A path model demonstrated that chronically accessible and stable sources are related to stable individual differences in life-satisfaction. Furthermore, the model supported the hypothesis that personality effects were mediated by chronically accessible and stable sources. In sum, the results are consistent with our theory that life-satisfaction judgments are based on chronically accessible sources. [source] Accessible and Free: Party System Data on JapanASIAN POLITICS AND POLICY, Issue 4 2010Katie Anne Cahill-Rincón No abstract is available for this article. [source] V2Al5Ge5: First Ternary Intermetallic in the V,Al,Ge System Accessible in Liquid Aluminum.CHEMINFORM, Issue 39 2004Xiuni Wu Abstract For Abstract see ChemInform Abstract in Full Text. [source] Extended spatial keyframing for complex character animationCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 3-4 2008Byungkuk Choi Abstract As 3D computer animation becomes more accessible to novice users, it makes it possible for these users to create high-quality animations. This paper introduces a more powerful system to create highly articulated character animations with an intuitive setup then the previous research, Spatial Keyframing (SK). As the main purpose of SK was the rapid generation of primitive animation over quality animation, we propose Extended Spatial Keyframing (ESK) that exploits a global control structure coupled with multiple sets of spatial keyframes, and hierarchical relationship between controllers. The generated structure can be flexibly embedded into the given rigged character, and the system enables the given character to be animated delicately by user performance. During the performance, the movement of the highest ranking controllers across the control hierarchy is recorded in layered style to increase the level of detail for final motions. Copyright © 2008 John Wiley & Sons, Ltd. [source] A web-based tool for control engineering teachingCOMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 3 2006J. Albino Méndez Abstract In this article a new tool for control engineering teaching is presented. The tool was implemented using Java applets and is freely accessible through Web. It allows the analysis and simulation of linear control systems and was created to complement the theoretical lectures in basic control engineering courses. The article is not only centered in the description of the tool but also in the methodology to use it and its evaluation in an electrical engineering degree. Two practical problems are included in the manuscript to illustrate the use of the main functions implemented. The developed web-based tool can be accessed through the link http://www.controlweb.cyc.ull.es. © 2006 Wiley Periodicals, Inc. Comput Appl Eng Educ 14: 178,187, 2006; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20080 [source] Interactive Web-based package for computer-aided learning of structural behaviorCOMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 3 2002X. F. Yuan Abstract This paper presents an innovative Web-based package named CALSB for computer-aided learning of structural behavior. The package was designed to be widely accessible through the Internet, user-friendly by the automation of many input functions and the extensive use of cursor movements, and dynamically interactive by linking all input and output data to a single graphical display on the screen. The package includes an analysis engine based on the matrix stiffness method, so the response of any two-dimensional skeletal structure can be predicted and graphically displayed. The package thus provides a virtual laboratory environment in which the user can "build and test" two-dimensional skeletal structures of unlimited choices to enhance his understanding of structural behavior. In addition, the package includes two other innovative features, structural games and paradoxes. The structural games in the package represent perhaps the first attempt at intentionally combining the learning of structural behavior with joy and excitement, while the structural paradoxes provide a stimulating environment conducive for the development of creative problem solving skills of the user. © 2002 Wiley Periodicals, Inc. Comput Appl Eng Educ 10: 121,136, 2002; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.10020 [source] NMR chemical shift measurements revisited: High precision measurementsCONCEPTS IN MAGNETIC RESONANCE, Issue 4 2007P. Granger Abstract Accurate chemical shifts are now accessible with high field NMR spectrometers. After the recall of the basic formulae, methods are proposed to measure chemical shifts with a high precision. Using two coaxial rotors at the magic angle, the necessary parameters used for correction are measured. The influence of different factors on the precision of the NMR measurements is discussed. Some proposals are given for MAS experiments used with solid-state samples. © 2007 Wiley Periodicals, Inc. Concepts Magn Reson Part A 30A: 184,193, 2007. [source] Implementation, performance, and science results from a 30.7 TFLOPS IBM BladeCenter clusterCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 2 2010Craig A. Stewart Abstract This paper describes Indiana University's implementation, performance testing, and use of a large high performance computing system. IU's Big Red, a 20.48 TFLOPS IBM e1350 BladeCenter cluster, appeared in the 27th Top500 list as the 23rd fastest supercomputer in the world in June 2006. In spring 2007, this computer was upgraded to 30.72 TFLOPS. The e1350 BladeCenter architecture, including two internal networks accessible to users and user applications and two networks used exclusively for system management, has enabled the system to provide good scalability on many important applications while being well manageable. Implementing a system based on the JS21 Blade and PowerPC 970MP processor within the US TeraGrid presented certain challenges, given that Intel-compatible processors dominate the TeraGrid. However, the particular characteristics of the PowerPC have enabled it to be highly popular among certain application communities, particularly users of molecular dynamics and weather forecasting codes. A critical aspect of Big Red's implementation has been a focus on Science Gateways, which provide graphical interfaces to systems supporting end-to-end scientific workflows. Several Science Gateways have been implemented that access Big Red as a computational resource,some via the TeraGrid, some not affiliated with the TeraGrid. In summary, Big Red has been successfully integrated with the TeraGrid, and is used by many researchers locally at IU via grids and Science Gateways. It has been a success in terms of enabling scientific discoveries at IU and, via the TeraGrid, across the US. Copyright © 2009 John Wiley & Sons, Ltd. [source] Cross-domain authorization for federated virtual organizations using the myVocs collaboration environmentCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 4 2009Jill Gemmill Abstract This paper describes our experiences building and working with the reference implementation of myVocs (my Virtual Organization Collaboration System). myVocs provides a flexible environment for exploring new approaches to security, application development, and access control built from Internet services without a central identity repository. The myVocs framework enables virtual organization (VO) self-management across unrelated security domains for multiple, unrelated VOs. By leveraging the emerging distributed identity management infrastructure. myVocs provides an accessible, secure collaborative environment using standards for federated identity management and open-source software developed through the National Science Foundation Middleware Initiative. The Shibboleth software, an early implementation of the Organization for the Advancement of Structured Information Standards Security Assertion Markup Language standard for browser single sign-on, provides the middleware needed to assert identity and attributes across domains so that access control decisions can be determined at each resource based on local policy. The eduPerson object class for lightweight directory access protocol (LDAP) provides standardized naming, format, and semantics for a global identifier. We have found that a Shibboleth deployment supporting VOs requires the addition of a new VO service component allowing VOs to manage their own membership and control access to their distributed resources. The myVocs system can be integrated with Grid authentication and authorization using GridShib. Copyright © 2008 John Wiley & Sons, Ltd. [source] CCLRC Portal infrastructure to support research facilitiesCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 6 2007Asif Akram Abstract The emergence of portal technology is providing benefits in developing portlet interfaces to applications to meet the current and future requirements of CCLRC facilities support. Portlets can be reused by different projects, e.g. the high-profile Integrative Biology project (with the University of Oxford), and in different Java Specification Request 168 Portlet Specification (JSR 168) compliant portal frameworks. Deployment and maintenance of applications developed as portlets becomes easier and manageable. A community process is already beginning and many portal frameworks come with free-to-use useful portlets. As rendering is carried out in the framework, applications can be easily accessible and internationalized. Portlets are compatible with J2EE, thus providing additional capabilities required in the service-oriented architecture (SOA). We also describe how Web service gateways can be used to provide many of the functionalities encapsulated in a portal server in a way to support Grid applications. Portals used as a rich client can allow users to customize or personalize their user interfaces and even their workflow and application access. CCLRC facilities will be able to leverage the work so far carried out on the National Grid Service (NGS) and e-HTPX portals, as they are fully functional and have received detailed user feedback. This demonstrates the usefulness of providing advanced capabilities for e-Research and having the associated business logic in a SOA loosely coupled from the presentation layer for an Integrated e-Science Environment. Copyright © 2006 John Wiley & Sons, Ltd. [source] Task Pool Teams: a hybrid programming environment for irregular algorithms on SMP clustersCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 12 2006Judith Hippold Abstract Clusters of symmetric multiprocessors (SMPs) are popular platforms for parallel programming since they provide large computational power for a reasonable price. For irregular application programs with dynamically changing computation and data access behavior, a flexible programming model is needed to achieve efficiency. In this paper we propose Task Pool Teams as a hybrid parallel programming environment to realize irregular algorithms on clusters of SMPs. Task Pool Teams combine task pools on single cluster nodes by an explicit message passing layer. They offer load balance together with multi-threaded, asynchronous communication. Appropriate communication protocols and task pool implementations are provided and accessible by an easy-to-use application programmer interface. As application examples we present a branch and bound algorithm and the hierarchical radiosity algorithm. Copyright © 2006 John Wiley & Sons, Ltd. [source] Refactoring service-based systems: how to avoid trusting a workflow serviceCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 10 2006Howard Chivers Abstract Grid systems span multiple organizations, so their workflow processes have security requirements, such as restricting access to data or ensuring that process constraints are observed. These requirements are often managed by the workflow component, because of the close association between this sub-system and the processes it enacts. However, high-quality security mechanisms and complex functionality are difficult to combine, so designers and users of workflow systems are faced with a tradeoff between security and functionality, which is unlikely to provide confidence in the security implementation. This paper resolves that tension by showing that process security can be enforced outside the workflow component. Separating security and process functionality in this way improves the quality of security protection, because it is implemented by standard system mechanisms; it also allows the workflow component to be deployed as a standard service, rather than a privileged system component. To make this change of design philosophy accessible outside the security community it is documented as a collection of refactorings, which include problem templates that identify suspect design practice, and target patterns that provide solutions. Worked examples show that these patterns can be used in practice to implement practical applications, with both traditional workflow security concerns, and Grid requirements. Copyright © 2005 John Wiley & Sons, Ltd. [source] Security Maintenance Mediation: a technology for preventing unintended security breachesCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 1 2004Roger (Buzz) KingArticle first published online: 4 DEC 200 Abstract Web-resident information is becoming ,smarter', in the sense that emerging technology will support the annotation of it with ontological terms, which will be used to locate and reuse information. This will pose a great security risk in the form of unintended breaches (as distinct from deliberate invasions). Web-resident information will be far more readily available and relevant, thus causing inadvertent releases of secure information to potentially cause it to be diffusely spread across the Internet. Then as this information is iteratively transformed and integrated with other information, it will become irretrievable and potentially used in a myriad of unpredictable ways. The problem is that ontological annotations, while making information more understandable in its original form, do not provide a means for easily capturing the complex semantics of information that has been transformed via abstraction, aggregation, and integration. This demands the development of a semantically rich way of specifying ,views' of Web information, to which security controls can be attached. Also needed is a way for users of secure information to easily and voluntarily blend,and thereby propagate,security controls as information is transformed. Information mediators designed by collaborative teams of experts are proposed as the vehicle for wrapping information, so that at each step of reuse, high-level views and their corresponding integrity controls can be made easily accessible to trusted users who will then be able to ensure their proper maintenance. Copyright © 2004 John Wiley & Sons, Ltd. [source] Synergistic Effects of Subsistence Hunting and Habitat Fragmentation on Amazonian Forest VertebratesCONSERVATION BIOLOGY, Issue 6 2001Carlos A. Peres These effects are likely to be considerably aggravated by forest fragmentation because fragments are more accessible to hunters, allow no (or very low rates of ,) recolonization from nonharvested source populations, and may provide a lower-quality resource base for the frugivore-granivore vertebrate fauna. I examined the likelihood of midsized to large-bodied bird and mammal populations persisting in Amazonian forest fragments of variable sizes whenever they continue to be harvested by subsistence hunters in the aftermath of isolation. I used data from a comprehensive compilation of game-harvest studies throughout Neotropical forests to estimate the degree to which different species and populations have been overharvested and then calculated the range of minimum forest areas required to maintain a sustainable harvest. The size distribution of 5564 Amazonian forest fragments,estimated from Landsat images of six regions of southern and eastern Brazilian Amazonia,clearly shows that these are predominantly small and rarely exceed 10 ha, suggesting that persistent overhunting is likely to drive most midsized to large vertebrate populations to local extinction in fragmented forest landscapes. Although experimental studies on this negative synergism remain largely unavailable, the prospect that increasingly fragmented Neotropical forest regions can retain their full assemblages of avian and mammalian species is unlikely. Resumen: La cacería de subsistencia tiene efectos negativos profundos sobre la diversidad de especies, la biomasa y estructura de las comunidades de vertebrados en bosques de la Amazonía que de otra forma están poco perturbadas. Estos efectos se agravan considerablemente por la fragmentación del bosque porque los fragmentos son más accesibles a los cazadores, no permiten la recolonización por poblaciones no cazadas o disminuyen las tasas de recolonizacíon y pueden proporcionar una base de recursos de menor calidad para la fauna de vertebrados frugívoro-granívoros. Examiné la posibilidad de persistencia de poblaciones de aves y mamíferos medianos a grandes en fragmentos de bosque de tamaño variable si continúan sujetos a la cacería de subsistencia como una consecuencia del aislamiento. Utilicé datos de una compilación extensiva de estudios de cacería en bosques neotropicales para estimar el grado en que diferentes especies y poblaciones han sido sobre explotadas y calculé el área de bosque minima requerida para mantener una cosecha sostensible. La distribucíon de tamaños de 5564 fragmentos de bosque amazónica, estimado a partir de imágues de Landsat de seis regiones del sur y del esté de la Amazonía brasileña indica claramente que estos fragmentós son principalmente pegueños y que rara vez exceden las lolta, lo que sugiere que la sobre cacería persistente probablemente lleve a la extincíon local de poblaciones de vertebrados de tamaño mediano a grande en paisajes boscosos fragmentados. Aunque estudios experimentales de este sinergismo negativo no están disponibles, la perspectiva de que las regiones neotropicales cada vez más fragmentadas, puedan retener las comunidades completas de aves y mamíferos poco es probable. [source] Particle in Cell Simulation of Low Temperature Laboratory PlasmasCONTRIBUTIONS TO PLASMA PHYSICS, Issue 8-9 2007K. Matyash Abstract Several applications of PIC simulations for understanding basic physics phenomena in low-temperature plasmas are presented: capacitive radiofrequency discharges in Oxygen, dusty plasmas and negative ion sources for heating of fusion plasmas. The analysis of these systems based on their microscopic properties as accessible with PIC gives improved insight into their complex behavior. These studies are results of joint efforts over about one decade of research groups from Greifswald University, Germany; Bari University, Italy; Keio University, Japan and Innsbruck University, Austria. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Mechanisms of transjunctional transport of NaCl and water in proximal tubules of mammalian kidneysACTA PHYSIOLOGICA, Issue 1 2002F. KIILArticle first published online: 30 APR 200 ABSTRACT Tight junctions and the intercellular space of proximal tubules are not accessible to direct measurements of fluid composition and transport rates, but morphological and functional data permit analysis of diffusion and osmosis causing transjunctional NaCl and water transport. In the S2 segment NaCl diffuses through tight junctions along a chloride gradient, but against a sodium gradient. Calculation in terms of modified Nernst,Fick diffusion equation after eliminating electrical terms shows that transport rates (300,500 pmol min,1 mm,1 tubule length) and transepithelial voltage of +2 mV are in agreement with observations. Diffusion coefficients are Dtj=1500 ,m2 s,1 in the S1 segment, and Dtj=90,100 ,m2 s,1 in the S2 segment where apical intercellular NaCl concentration is 132 mM, 1 mM below complete stop (Dtj=0 and Donnan equilibrium). Tight junctions with gap distance 6 Å are impermeable to mannitol (effective molecular radius 4 Å); reflection coefficients are ,=0.92 for NaHCO3 and ,=0.28 for NaCl, because of difference in anion size. The osmotic force is provided by a difference in effective transjunctional osmolality of 10 mOsm kg,1 in the S1 segment and 30 mOsm kg,1 in the S2 segment, where differences in transjunctional concentration contribute with 21 mOsm kg,1 for NaHCO3 and ,4 mOsm kg,1 for NaCl. Transjunctional difference of 30 mOsm kg,1 causes a volume flow of 2 nL min,1 mm,1 tubule length. Luminal mannitol concentration of 30 mM stops all volume flow and diffusive and convective transport of NaCl. In conclusion, transjunctional diffusion and osmosis along gradients generated by transcellular transport of other solutes account for all NaCl transport in proximal tubules. [source] Paper Versus Electronic Medical Records: The Effects of Access on Physicians' Decisions to Use Complex Information Technologies,DECISION SCIENCES, Issue 2 2009Virginia Ilie ABSTRACT This study examines physicians' responses to complex information technologies (IT) in the health care supply chain. We extend individual-level IT adoption models by incorporating a new construct: system accessibility. The main premise of the study is, when faced with a decision between alternate IT systems, individual users tend to select and make use of the technology or system that is most readily accessible. We discuss both physical and logical dimensions of accessibility as they relate to adoption of electronic medical records (EMR). Physical accessibility refers to the availability of computers that can be used to access EMR, while logical accessibility refers to the ease or difficulty of logging into the system. Using data from a survey of 199 physicians practicing in a large U.S. hospital, we show that, when deciding between the paper chart and EMR, accessibility is an important consideration in a physician's decision to use the system. Both dimensions of accessibility act as barriers to EMR use intentions through their indirect effect on physicians' perceptions of EMR usefulness and ease of use. Logical access also has a direct effect on EMR use intentions. We conclude that accessibility is an important factor that limits acceptance of complex IT such as EMR. [source] The apparent volumes of distribution of H1 receptor antagonistsDERMATOLOGIC THERAPY, Issue 4 2000Jean-Paul Tillement ABSTRACT: The apparent volume of distribution (VD) of a drug estimates its distribution into the body. Referring to the volume of exchangeable water (0.6 L/kg body weight), it indicates if tissue distribution is extensive when VD is greater than 0.6 L/kg or poor if VD is less than 0.6 L/kg. Its interest in the selection of an appropriate drug is found after comparing the map of selected targets (mainly receptors) to be reached by the drug, the accessibility of these targets by the drug, and the VD necessary and sufficient to reach them. This analysis is here applied to H1 receptor antagonists, a pharmacologic class, where target cells, endothelial cells such as eosinophils, mastocytes, basophils, and smooth fibers have receptors on the external side of cell membranes and thus are more readily accessible from blood than toxic sites located inside cells (heart, brain, liver). Of the H1 receptor antagonists marketed today, cetirizine has the lowest VD, 0.4 L/kg, enough to reach selected targets without extensive distribution in organs where it would be useless. These characteristics are related to its chemical amphoteric structure. [source] OVERCOMING BARRIERS TO PAIN RELIEF IN THE CARIBBEANDEVELOPING WORLD BIOETHICS, Issue 3 2009CHERYL MACPHERSON ABSTRACT This paper examines pain and pain relief in the Caribbean, where pain is widely perceived as an unavoidable part of life, and where unnecessary suffering results from untreated and under treated pain. Barriers to pain relief in the Caribbean include patient and family attitudes, inadequate knowledge among health professionals and unduly restrictive regulations on the medical use of opioids. Similar barriers exist all over the world. This paper urges medical, nursing and public health professionals, and educators to examine attitudes towards pain and pain relief and to work towards making effective pain relief and palliation more accessible. It recommends that i) health professionals and officials be better educated about pain, palliation and opioids, ii) regulatory restrictions be updated in light of clinical and scientific evidence, iii) opioid procurement policies be adjusted to facilitate increased medical use, iv) medical charts and records be modified to routinely elicit and document patients levels of pain, and v) educational campaigns be developed to inform the public that moderate and severe pain can be safely relieved at the end of life and other stages of life. The professional, respectful, and beneficent response to patients in pain is to provide rapid and aggressive pain relief or to urgently consult a pain or palliative specialist. When a health system hinders such efforts the ethical response is to identify, facilitate and advocate for overcoming barriers to improvement. [source] Cnidarians and the evolutionary origin of the nervous systemDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 3 2009Hiroshi Watanabe Cnidarians are widely regarded as one of the first organisms in animal evolution possessing a nervous system. Conventional histological and electrophysiological studies have revealed a considerable degree of complexity of the cnidarian nervous system. Thanks to expressed sequence tags and genome projects and the availability of functional assay systems in cnidarians, this simple nervous system is now genetically accessible and becomes particularly valuable for understanding the origin and evolution of the genetic control mechanisms underlying its development. In the present review, the anatomical and physiological features of the cnidarian nervous system and the interesting parallels in neurodevelopmental mechanisms between Cnidaria and Bilateria are discussed. [source] Dietary Implications of Supermarket Development: A Global PerspectiveDEVELOPMENT POLICY REVIEW, Issue 6 2008Corinna Hawkes Five decisions by supermarket operators have important dietary implications: the location of their outlets; the foods they sell; the prices they charge; the promotional strategies they use; and the nutrition-related activities they implement. These decisions influence food accessibility, availability, prices and desirability, which in turn influence the decisions consumers make about food. Based on a comprehensive literature review, this article finds that the dietary implications are both positive , supermarkets can make a more diverse diet available and accessible to more people , and negative , supermarkets can reduce the ability of marginalised populations to purchase a high-quality diet, and encourage the consumption of energy-dense, nutrient-poor highly-processed foods. Overall, the most universally applicable dietary implication is that supermarkets encourage consumers to eat more, whatever the food. [source] Adult bone marrow,derived stem cells for organ regeneration and repairDEVELOPMENTAL DYNAMICS, Issue 12 2007Florian Tögel Abstract Stem cells have been recognized as a potential tool for the development of innovative therapeutic strategies. There are in general two types of stem cells, embryonic and adult stem cells. While embryonic stem cell therapy has been riddled with problems of allogeneic rejection and ethical concerns, adult stem cells have long been used in the treatment of hematological malignancies. With the recognition of additional, potentially therapeutic characteristics, bone marrow,derived stem cells have become a tool in regenerative medicine. The bone marrow is an ideal source of stem cells because it is easily accessible and harbors two types of stem cells. Hematopoietic stem cells give rise to all blood cell types and have been shown to exhibit plasticity, while multipotent marrow stromal cells are the source of osteocytes, chondrocytes, and fat cells and have been shown to support and generate a large number of different cell types. This review describes the general characteristics of these stem cell populations and their current and potential future applications in regenerative medicine. Developmental Dynamics 236:3321,3331, 2007. © 2007 Wiley-Liss, Inc. [source] Chick limbs with mouse teeth: An effective in vivo culture system for tooth germ development and analysisDEVELOPMENTAL DYNAMICS, Issue 1 2003Eiki Koyama Abstract Mouse tooth germ development is currently studied by three main approaches: in wild-type and mutant mouse lines, after transplantation of tooth germs to ectopic sites, and in organ culture. The in vivo approaches are the most physiological but do not provide accessibility to tooth germs for further experimental manipulation. Organ cultures, although readily accessible, do not sustain full tooth germ development and are appropriate for short-term analysis. Thus, we sought to establish a new approach that would combine experimental accessibility with sustained development. We implanted fragments of embryonic day 12 mouse embryo first branchial arch containing early bud stage tooth germs into the lateral mesenchyme of day 4,5 chick embryo wing buds in ovo. Eggs were reincubated, and implanted tissues were examined by histochemistry and in situ hybridization over time. The tooth germs underwent seemingly normal growth, differentiation, and morphogenesis. They reached the cap, bell, and crown stages in approximately 3, 6, and 10 days, respectively, mimicking in a striking manner native temporal patterns. To examine mechanisms regulating tooth germ development, we first implanted tooth germ fragments, microinjected them with neutralizing antibodies to the key signaling molecule Sonic hedgehog (Shh), and examined them over time. Tooth germ development was markedly delayed, as revealed by poor morphogenesis and lack of mature ameloblasts and odontoblasts displaying characteristic traits such as an elongated cell shape, nuclear relocalization, and amelogenin gene expression. These phenotypic changes began to be reversed upon further incubation. The data show that the limb bud represents an effective, experimentally accessible as well as economical system for growth and analysis of developing tooth germs. The inhibitory effects of Shh neutralizing antibody treatment are discussed in relation to roles of this signaling pathway proposed by this and other groups previously. © 2002 Wiley-Liss, Inc. [source] Integration and differentiation of human embryonic stem cells transplanted to the chick embryoDEVELOPMENTAL DYNAMICS, Issue 1 2002Ronald S. Goldstein Abstract Human embryonic stem (ES) cells are pluripotent cells that can differentiate into a large array of cell types and, thus, hold promise for advancing our understanding of human embryology and for contributing to transplantation medicine. In this study, differentiation of human ES cells was examined in vivo by in ovo transplantation to organogenesis-stage embryos. Colonies of human ES cells were grafted into or in place of epithelial-stage somites of chick embryos of 1.5 to 2 days of development. The grafted human ES cells survived in the chick host and were identified by vital staining with carboxyfluorescein diacetate or use of a green fluorescent protein,expressing cells. Histologic analysis showed that human ES cells are easily distinguished from host cells by their larger, more intensely staining nuclei. Some grafted cells differentiated en masse into epithelia, whereas others migrated and mingled with host tissues, including the dorsal root ganglion. Colonies grafted directly adjacent to the host neural tube produced primarily structures with the morphology and molecular characteristics of neural rosettes. These structures contain differentiated neurons as shown by ,-3-tubulin and neurofilament expression in axons and cell bodies. Axons derived from the grafted cells penetrate the host nervous system, and host axons enter the structures derived from the graft. Our results show that human ES cells transplanted in ovo survive, divide, differentiate, and integrate with host tissues and that the host embryonic environment may modulate their differentiation. The chick embryo, therefore, may serve as an accessible and unique experimental system for the study of in vivo development of human ES cells. © 2002 Wiley-Liss, Inc. [source] Methanol exposure interferes with morphological cell movements in the Drosophila embryo and causes increased apoptosis in the CNSDEVELOPMENTAL NEUROBIOLOGY, Issue 3 2004Dervla M. Mellerick Abstract Despite the significant contributions of tissue culture and bacterial models to toxicology, whole animal models for developmental neurotoxins are limited in availability and ease of experimentation. Because Drosophila is a well understood model for embryonic development that is highly accessible, we asked whether it could be used to study methanol developmental neurotoxicity. In the presence of 4% methanol, approximately 35% of embryos die and methanol exposure leads to severe CNS defects in about half those embryos, where the longitudinal connectives are dorsally displaced and commissure formation is severely reduced. In addition, a range of morphological defects in other germ layers is seen, and cell movement is adversely affected by methanol exposure. Although we did not find any evidence to suggest that methanol exposure affects the capacity of neuroblasts to divide or induces inappropriate apoptosis in these cells, in the CNS of germ band retracted embryos, the number of apoptotic nuclei is significantly increased in methanol-exposed embryos in comparison to controls, particularly in and adjacent to the ventral midline. Apoptosis contributes significantly to methanol neurotoxicity because embryos lacking the cell death genes grim, hid, and reaper have milder CNS defects resulting from methanol exposure than wild-type embryos. Our data suggest that when neurons and glia are severely adversely affected by methanol exposure, the damaged cells are cleared by apoptosis, leading to embryonic death. Thus, the Drosophila embryo may prove useful in identifying and unraveling mechanistic aspects of developmental neurotoxicity, specifically in relation to methanol toxicity. © 2004 Wiley Periodicals, Inc. J Neurobiol 60: 308,318, 2004 [source] Prescription drug misuse: Is technology friend or foe?DRUG AND ALCOHOL REVIEW, Issue 1 2009SUZANNE NIELSEN Abstract Introduction and Aims. Prescription drug misuse and related harms have been increasing considerably over the past decade. At the same time, there has also been rapid growth in the use of online and Internet technologies. Thus, it is important that we understand the role online and Internet technologies play in prescription drug misuse. Design and Methods. Published work addressing the role of technology in prescription drug misuse is explored. Topics include: Internet supply, online monitoring of prescription drug use trends and electronic prescription monitoring. Results. Little is known about the prevalence of acquiring prescription drugs from online pharmacies. Prescription drugs are easily accessible through vendor websites, and ,rogue' no-prescription websites have proven difficult to control. There has so far been limited application of real-time monitoring to prevent overuse of prescription medications. Online monitoring of drug use trends may also prove to be a useful and timely source of information about new methods of ,off-label' prescription drug use. Discussion and Conclusions. Technology has the potential to play a more prominent role in facilitating drug acquisition, while also enhancing the monitoring and prevention of prescription drug misuse. As technology becomes more ubiquitous in everyday life, the continued investigation of its relationship with prescription drug misuse becomes even more important.[Nielsen S, Barratt MJ. Prescription drug misuse: Is technology friend or foe? Drug Alcohol Rev 2009;28:81,86] [source] The role of remote community stores in reducing the harm resulting from tobacco to Aboriginal peopleDRUG AND ALCOHOL REVIEW, Issue 3 2006ROWENA G. IVERS Abstract The objective of this study was to assess the potential for reducing the harm resulting from tobacco use through health promotion programmes run in community stores in remote Aboriginal communities. The Tobacco Project utilised data from 111 stakeholder interviews (72 at baseline and 71 at follow-up after 12 months) assessing presence of sales to minors, tobacco advertising, labelling and pricing. It also involved the assessment of observational data from community stores and comments obtained from 29 tobacco vendors derived from community surveys. Sales of tobacco to minors were not reported in community stores and all stores complied with requirements to display the legislated signage. However, tobacco was accessible to minors through a vending machine and through independent vendors. Only one store displayed tobacco advertising; all stores had displayed anti-tobacco health promotion posters or pamphlets. Pricing policies in two stores may have meant that food items effectively subsidised the cost of tobacco. All stores had unofficial no-smoking policies in accessible parts of the store. Remote community stores complied with existing legislation, aside from allowing access of minors to vending machines. There may still be potential for proactive tobacco education campaigns run through community stores and for a trial assessing the effect of changes in tobacco prices on tobacco consumption. [source] Microanatomical diversity of the humerus and lifestyle in lissamphibiansACTA ZOOLOGICA, Issue 2 2009Aurore Canoville Abstract A study of body size and the compactness profile parameters of the humerus of 37 species of lissamphibians demonstrates a relationship between lifestyle (aquatic, amphibious or terrestrial) and bone microstructure. Multiple linear regressions and variance partitioning with Phylogenetic eigenVector Regressions reveal an ecological and a phylogenetic signal in some body size and compactness profile parameters. Linear discriminant analyses segregate the various lifestyles (aquatic vs. amphibious or terrestrial) with a success rate of up to 89.2%. The models built from data on the humerus discriminate aquatic taxa relatively well from the other taxa. However, like previous models built from data on the radius of amniotes or on the femur of lissamphibians, the new models do not discriminate amphibious taxa from terrestrial taxa on the basis of body size or compactness profile data. To make our inference method accessible, spreadsheets (see supplementary material on the website), which allow anyone to infer a lissamphibian lifestyle solely from body size and bone compactness parameters, were produced. No such easy implementation of habitat inference models is found in earlier papers on this topic. [source] Patterns and correlates of substance use amongst juvenile detainees in New South Wales 1989,99DRUG AND ALCOHOL REVIEW, Issue 1 2003JAN COPELAND Abstract In the decade 1989,99 there have been significant changes in the patterns of substance use in the Australian community. Juvenile offenders have been a sentinel population of these emerging trends. The social and personal costs associated with adolescent substance use, especially where it leads to increased criminal offending requires urgent attention. This study was a replication of the 1989 and 1994 surveys of young people in detention in New South Wales, Australia. The 300 voluntary participants from nine detention centres had a similar demographic profile to participants of the previous surveys. They were predominantly male (90%) with a mean age of 16.5 years and an over-representation of Aboriginal and Torres Straits Islander peoples. The patterns of lifetime alcohol and tobacco use were stable over the decade, with particular increases in amphetamine, opioid and cocaine use since 1994. The more concerning pattern of at least weekly substance use revealed significant increases in cannabis, opioid and cocaine use since 1994, but a significant decrease in the frequent use of alcohol. This study also reports on high levels of negative health and psychosocial consequences of substance use, including overdose, among this group. High levels of self-reported depression and suicidal behaviours, family and gender issues are also discussed. Encouragingly, there was a relatively high level of self-recognized treatment need for substance use and mental health problems among the sample. This highlights further the growing need for the development and dissemination of novel interventions that harness this willingness and actively engage, motivate and maintain these young people in accessible, appropriate and effective interventions. [source] | |||||||||||||||||||||||||||||||||||||||||||