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Inherent Complexity (inherent + complexity)
Selected AbstractsLIVING THE QUESTIONS: RILKE'S CHALLENGE TO OUR QUEST FOR CERTAINTYEDUCATIONAL THEORY, Issue 1 2007Mordechai Gordon The quest for certainty in education refers to our desire to gain a sense of psychological security and more control over a field that is fundamentally indeterminate. This quest implies an unwillingness to live with the inherent complexities and risks of education. After exploring the meaning and import of Rilke's challenge and comparing it to the position of Socrates, Gordon uses Rilke's insight to analyze a specific educational experience and then discusses some of its educational implications for teacher education. [source] Formation and applications of stable 10 nm to 500 nm supramolecular porphyrinic materialsISRAEL JOURNAL OF CHEMISTRY, Issue 3 2005Charles Michael Drain Nanoscaled materials of organic dyes are of interest for a variety of potential applications because of the rich photonic properties that this class of molecules can impart. One mode to form such nanoscaled materials is via self-organization and self-assembly, using reasonably well understood methods in supramolecular chemistry. But there are inherent complexities that arise from the use of organic-based supramolecular materials, including stability toward dioxygen, structural stability, and nanoarchitectures that may change with environmental conditions. Porphyrinoids have rich photonic properties yet are remarkably stable, have a rigid core, are readily functionalized, and metalation of the macrocycle can impart a plethora of optical, electronic, and magnetic properties. While there are many <10 nm porphyrinic assemblies, which may or may not self-organize into crystals, there is a paucity of 10,500 nm porphyrinic materials that can be isolated and stored. A variety of strategies towards the latter nanoscopic porphyrinic materials are discussed in terms of design, construction, and nanoarchitecture. The hierarchical structures include colloids, nanorods, nanotubes, nanorings, and nano-crystalline materials. This prolegomenon emphasizes the supramolecular chemistry, structure-stability, and structure-function relationships. The goal herein is to examine general trends and delineate general principles. [source] Bathing Disability in Community-Living Older Persons: Common, Consequential, and ComplexJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 11 2004Aanand D. Naik MD Objectives: To identify the specific bathing subtasks that are affected in community-living-older persons with bathing disability and to determine the self-reported reasons for bathing disability. Design: Cross-sectional study. Setting: General community of greater New Haven, Connecticut. Participants: A total of 626 community-living persons, aged 73 and older, who completed a comprehensive assessment, including a detailed evaluation of bathing disability. Measurements: Trained research nurses assessed bathing disability (defined as requiring personal assistance or having difficulty washing and drying the whole body), the specific bathing subtasks that were affected, and the main reasons (up to three) for bathing disability. Results: Disability in bathing was present in 195 (31%) participants; of these, 97 required personal assistance (i.e., dependence), and 98 had difficulty bathing. Participants with bathing disability reported a mean±standard deviation of 4.0±2.4 affected subtasks. The prevalence rate of disability for the eight prespecified bathing subtasks ranged from 25% for taking off clothes to 75% for leaving the bathing position. The majority of participants (59%) provided more than one reason for bathing disability. The most common reasons cited by participants for their bathing disability were balance problems (28%), arthritic complaints (26%), and fall or fear of falling (23%). Conclusion: For community-living older persons, disability in bathing is common, involves multiple subtasks, and is attributable to an array of physical and psychological problems. Preventive and restorative interventions for bathing disability will need to account for the inherent complexity of this essential activity of daily living. [source] Functional and molecular MR imaging of angiogenesis: Seeing the target, seeing it workJOURNAL OF CELLULAR BIOCHEMISTRY, Issue S39 2002Michal NeemanArticle first published online: 16 JAN 200 Abstract Intensive research over the last years led to the discovery of multiple molecular pathways and intricate regulatory network controlling the growth and regression of blood vessels in general and angiogenesis in particular. The difficulties in elucidation of the regulation of angiogenesis, stems from the inherent complexity due to participation of many cell types, under a dominant impact of physiological and environmental effects of flow, perfusion, and oxygenation. Major advances were achieved with the use of sophisticated transgenic mice models engineered so as to provide spatially and temporally controlled expression of specific factors alone or in combination. In vivo analysis of these models frequently requires the use of non-invasive imaging modalities for measurement of functional parameters of the vasculature along with dynamic molecular information. Optical methods are extensively applied for the study of angiogenesis [Brown et al., 2001] but provide very limited tissue penetration. MRI offers the advantage of being non-invasive with uniform and relatively high spatial resolution for deep tissues. Multiple MRI approaches for monitoring angiogenesis were developed over the last years, each looking at a particular step in the process. The aim of this paper is to analyze the clinical, pharmaceutical, and biological needs for imaging of angiogenesis, and to critically evaluate the strengths and weaknesses of functional and molecular imaging for monitoring angiogenesis. The inherent problem of validation of different measures of angiogenesis, and the advantages and limitations associated with application of MRI based methods, as surrogates for other measurements of angiogenesis will be discussed. The terms molecular imaging and functional imaging are frequently loosely defined with a significant overlap between the two. For the sake of this paper we will apply a narrower definition of both terms, where molecular imaging will apply to methods directed towards detection of specific biological molecules that participate directly in (regulation of) a physiological process; while functional imaging will be used to describe those methods that aim to detect the physiological response to a defined (molecular) stimulus. J. Cell. Biochem. Suppl. 39: 11,17, 2002. © 2002 Wiley-Liss, Inc. [source] Monte Carlo model of UV-radiation interaction with TiO2 -coated spheresAICHE JOURNAL, Issue 10 2007Gustavo E. Imoberdorf Abstract Photocatalysis is one of the advanced oxidation techniques that are being studied for the treatment of polluted air and water from different sources. From a kinetic point of view, photocatalytic reaction rates are strongly dependent not only on the reactant and product concentrations, but also on the rate of photon absorption. Unfortunately, the local rate of photon absorption is usually difficult to evaluate because of (i) the inherent complexity of the system and (ii) the lack of data concerning the photocatalyst optical properties. The final objective of this project is focused on the development of a complete model of the radiation field; the bed structure, and the flow pattern to describe the operation of a fixed bed photocatalytic reactor. In this article, the interaction between radiative energy and TiO2 -coated fused-silica sphere beds was studied. The proposed model was built applying the Monte Carlo method, taking into account the complex reflection/refraction/absorption interactions between radiation and the packed bed. To obtain experimental measurements, an ad hoc device was designed and built. This device allows us to validate the proposed radiation model, and to obtain the optical parameters of the composite photocatalyst, i.e., the refractive index and the surface rough index of the fused-silica spheres, as well as the refractive index and the optical thickness of the TiO2 films. © 2007 American Institute of Chemical Engineers AIChE J, 2007 [source] Policy implementation: Implications for evaluationNEW DIRECTIONS FOR EVALUATION, Issue 124 2009Amy DeGroff Policy implementation reflects a complex change process where government decisions are transformed into programs, procedures, regulations, or practices aimed at social betterment. Three factors affecting contemporary implementation processes are explored: networked governance, sociopolitical context and the democratic turn, and new public management. This frame of reference invites evaluators to consider challenges present when evaluating macrolevel change processes, such as the inherent complexity of health and social problems, multiple actors with variable degrees of power and influence, and a political environment that emphasizes accountability. The evaluator requires a deep and cogent understanding of the health or social issues involved; strong analysis and facilitation skills to deal with a multiplicity of values, interests, and agendas; and a comprehensive toolbox of evaluation approaches and methods, including network analysis to assess and track the interconnectedness of key champions (and saboteurs) who might affect intervention effects and sustainability. © Wiley Periodicals, Inc., and the American Evaluation Association. [source] Social trajectories and the evolution of social behaviorOIKOS, Issue 2 2002S. Helms Cahan Current research on the evolution of sociality seeks to integrate a wealth of species-specific studies to draw more generalized conclusions. Developing a unified theory of social evolution has been a challenging process, hampered by the inherent complexity of social systems. By viewing a species' social structure as the result of a series, or "trajectory", of decisions individuals make about whether or not to disperse from their natal territory, whether to co-breed or refrain from breeding, and whether or not to provide alloparental care, we can more easily evaluate whether selective factors influencing each social decision are similar across taxa. At the same time, the social trajectory framework highlights the interrelationships among different social decisions, both throughout the life of an individual and over evolutionary time. There are likely to be multiple unifying themes within sociality research; we hope that the simple framework outlined here will promote exchange between researchers across taxonomic disciplines to begin to identify common principles. [source] From proteomics to systems biology of bacterial pathogens: Approaches, tools, and applicationsPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 6 2007Uwe Plikat Dr. Abstract The hallmark of a systems biology approach is the integration of computational tools with experimental data encompassing multiple classes of biomolecules across different functional levels. Equally important as the availability of reasonably comprehensive information at the gene, protein, and metabolite levels is the development of adequate analysis and visualization tools to reduce the inherent complexity to interpretable dimensions. In this paper, we describe the integration of a 2-D gel-based proteome map of Staphylococcus aureus Mu50 with genomic and transcriptomic information through a customized data integration and user interface built on the Ensembl genome browser. We illustrate its application and potential through the analysis of a defined system perturbation caused by a mutation in the formyltransferase gene. We envision that this software package, which we called Insieme, can support the development of novel antibiotics by allowing a systems-based view of the bacterial response pathways. [source] Research Review: Crossing syndrome boundaries in the search for brain endophenotypesTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 6 2009Yonata Levy The inherent imprecision of behavioral phenotyping is the single most important factor contributing to the failure to discover the biological factors that are involved in psychiatric and neurodevelopmental disorders (e.g., Bearden & Freimer, 2006). In this review article we argue that in addition to an appreciation of the inherent complexity at the biological level, a rather urgent task facing behavioral scientists involves a reconsideration of the role that clinical syndromes play in psychological theorizing, as well as in research into the biological basis of cognition and personality. Syndrome heterogeneity, cross-syndrome similarities and syndrome comorbidities question the relevance of syndromes to biological research. It is suggested that the search for brain endophenotypes, intermediate between genes and behavior, should be based on cross-syndrome, trait classification. Cohort selection should rest on behavioral homogeneity, enabling, when necessary, syndrome heterogeneity. [source] Overview of Guidelines for Establishing a Face Transplant Program: A Work in ProgressAMERICAN JOURNAL OF TRANSPLANTATION, Issue 5 2010M. Siemionow Since 2005, nine face transplants have been performed in four countries: France, the United States (US), China and Spain. These encouraging short-term outcomes, with the longest survivor approaching 5 years, have led to an increased interest in establishing face transplant programs worldwide. Therefore, the purpose of this article is to facilitate the dissemination of relevant details as per our experience in an effort to assist those medical centers interested in establishing a face transplant program. In this article, we address the logistical challenges involved with face transplantation; including essential program requirements, protocol details, face transplant team assembly, project funding, the organ procurement organization and the coroner. It must be emphasized that face transplantation is still experimental and its therapeutic value remains to be validated. All surgical teams pursuing this endeavor must dedicate an attention to detail and should accept a responsibility to publish their outcomes in a transparent manner in order to contribute to the international field. However, due to its inherent complexity, facial transplantation should only be performed by university-affiliated medical institutions capable of orchestrating a specialized multidisciplinary team with a long-term commitment to its success. [source] | |||||||||||||||||||