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Interacting Components (interacting + component)
Selected AbstractsWhat Is Critical Globalization Studies?INTERNATIONAL STUDIES PERSPECTIVES, Issue 3 2004James H. Mittelman From a critical perspective, precisely what kind of knowledge about globalization is meaningful? The distinctive province of a critical orientation to globalization is coming to be defined by a complex of five interacting components: reflexivity, historicism, decentering, crossovers between social inquiry and other streams of knowledge, and an emphasis on strategic transformations. Critical globalization studies may be employed to identify diverse tendencies in world order, parts of a contradictory whole that coexist, with different logics colliding with one another. These are elements of the old configuration, multilateral globalization; the contemporary structure, militarized globalization; and the potential constellation, democratic globalization. The motor of transformation is not only countervailing power but also alternative knowledge, which should be demystifying and enabling. [source] In Silico Modeling and Simulation of Bone Biology: A ProposalJOURNAL OF BONE AND MINERAL RESEARCH, Issue 7 2005Nadine A Defranoux Abstract Contemporary, computer-based mathematical modeling techniques make it possible to represent complex biological mechanisms in a manner that permits hypothesis testing in silico. This perspective shows how such approaches might be applied to bone remodeling and therapeutic research. Currently, the dominant conceptual model applied in bone research involves the dynamic balance between the continual build-up and breakdown of bone matrix by two cell types, the osteoblasts and osteoclasts, acting together as a coordinated, remodeling unit. This conceptualization has served extraordinarily well as a focal point for understanding how mutations, chemical mediators, and mechanical force, as well as external influences (e.g., drugs, diet) affect bone structure and function. However, the need remains to better understand and predict the consequences of manipulating any single factor, or combination of factors, within the context of this complex system's multiple interacting pathways. Mathematical models are a natural extension of conceptual models, providing dynamic, quantitative descriptions of the relationships among interacting components. This formalization creates the ability to simulate the natural behavior of a system, as well as its modulation by therapeutic or dietetic interventions. A number of mathematical models have been developed to study complex bone functions, but most include only a limited set of biological components needed to address a few specific questions. However, it is possible to develop larger, multiscale models that capture the dynamic interactions of many biological components and relate them to important physiological or pathological outcomes that allow broader study. Examples of such models include Entelos' PhysioLab platforms. These models simulate the dynamic, quantitative interactions among a biological system's biochemicals, cells, tissues, and organs and how they give rise to key physiologic and pathophysiologic outcomes. We propose that a similar predictive, dynamical, multiscale mathematical model of bone remodeling and metabolism would provide a better understanding of the mechanisms governing these phenomena as well as serve as an in silico platform for testing pharmaceutical and clinical interventions on metabolic bone disease. [source] Neuregulin-1 induces acetylcholine receptor transcription in the absence of GABP, phosphorylationJOURNAL OF NEUROSCIENCE RESEARCH, Issue 5 2008Carter A. Herndon Abstract Localization of acetylcholine receptors (AChRs) to the postsynaptic region of muscle is mediated in part by transcriptional mechanisms, because the genes encoding AChR subunits are transcribed selectively in synaptic myofiber nuclei. Neuregulin-1 (NRG-1) is a synaptic signal and induces transcription of AChRs in muscle cells. Signaling by NRG-1 is thought to involve the transcription factor GA-binding protein (GABP), a heterodimer of GABP,, which is a member of the Ets family, and GABP,. Phosphorylation of certain other Ets proteins outside the Ets DNA-binding domain serves to stimulate transcriptional activation in response to extracellular signals. According to previous studies, NRG-1 stimulates phosphorylation of GABP, at threonine 280 in the N-terminal region adjacent to the Ets domain, suggesting that GABP, phosphorylation might contribute to NRG-1 responsiveness. To determine the functional importance of the N-terminal region of GABP, and whether its function is regulated by phosphorylation, we generated muscle cell lines in which the endogenous GABP, gene was deleted and replaced by variants of GABP, mutated in the N-terminal region. We found that NRG-1 can induce transcription in cells with mutated T280 phosphorylation site, indicating that T280 phosphorylation does not contribute to NRG-1 responsiveness. We also found that NRG-1-induced transcription occurs in cells missing the entire N-terminal region of GABP,. Because NRG-1 signaling is not expected to alter the function of the C-terminal region, which remains in these cells, these results suggest that GABP,, or other interacting components, rather than GABP, directly, is targeted by NRG-1 signaling. © 2007 Wiley-Liss, Inc. [source] Two- and three-dimensional hydrated coordination polymers of diaqualanthanum(3+) ions with 2-hydroxypropanedioate, oxalate and acetate anions as bridging ligandsACTA CRYSTALLOGRAPHICA SECTION C, Issue 4 2009Rajesh Koner The title compounds, poly[[tetraaquadi-,-2-hydroxypropanedioato-,-oxalato-dilanthanum(III)] tetrahydrate], {[La2(C2O4)(C3H2O5)2(H2O)4]·4H2O}n, (I), and poly[[tetra-,-acetato-tetraaqua-,-oxalato-dilanthanum(III)] dihydrate], {[La2(C2O4)(C2H3O2)4(H2O)4]·2H2O}n, (II), represent crystalline hydrates of coordination polymers of diaqualanthanum(3+) ions with different combinations of bridging carboxylate ligands, viz. 2-hydroxypropanedioate and oxalate in a 2:2:1 ratio in (I), and acetate and oxalate in a 2:4:1 ratio in (II). While the acetate component was one of the reactants used, the other ligands were obtained in situ by aerial oxidation of the dihydroxyfumaric acid present in the reactions. The crystal structure of (I) consists of two-dimensional polymeric arrays with water molecules intercalated between and hydrogen bonded to the arrays. The oxalate components are located on inversion centres. The crystal structure of (II) reveals an open three-dimensional polymeric connectivity between the interacting components, with the solvent water molecules incorporated within the intralattice voids and hydrogen bonded to the polymeric framework. The LaIII ion and the noncoordinated water molecules are located on axes of twofold symmetry. The oxalate group is centred at the 222 symmetry site, the intersection of the three rotation axes. The coordination number of the LaIII ion in the two structures is 10. The significance of this study lies mainly in the characterization of two new coordination polymers, as well as in the confirmation that dihydroxyfumaric acid tends to rearrange to form smaller components in standard laboratory procedures, and should be considered a poor reagent for formulating hybrid coordination polymers with metal ions. [source] Understanding Consciousness Using Systems Approaches and Lexical UniversalsANTHROPOLOGY OF CONSCIOUSNESS, Issue 2 2004Michael Winkelman Ph.D. The numerous perspectives offered on consciousness reflect a multifaceted phenomenon that results from a system of relations. An etymological approach identifies linguistic roots of the meanings of consciousness and illustrates their concern with self-referenced informational relationships of an organism with its environment, a "knowing system" formed in the epistemological relations between knower and known. Common elements of contemporary models suggest that consciousness involves interacting components of a system, including: attention-awareness; phenomenal experiences; self reference; action-behavior, including representations and learning; use of information; interpretation of meaning; goal-directed behavior; and systems of social reference. It is suggested that manifestations of consciousness through the physical properties of the brain are universally represented in language. A preliminary systems model of consciousness is outlined with widespread lexical roots proposed as a culture-neutral framework for constructing theories of consciousness and identifying cognitive constructs which reveal the epistemological roots of consciousness within Indo-European traditions. [source] Hydrogen-Bond-Guided Self-Assembly of Nucleotides on a Receptor-Array SurfaceCHEMISTRY - A EUROPEAN JOURNAL, Issue 34 2010Dr. Dmitry Abstract The hydrogen-bond-guided self-assembly of 5,-ribonucleotides bearing adenine(A), cytosine (C), uracil (U), or guanine (G) bases from aqueous solution on a lipid-like surface decorated with synthetic bis(ZnII,cyclen) (cyclen=1,4,7,10-tetraazacyclodododecane) metal,complex receptor sites is described. The process was studied by using surface plasmon resonance spectroscopy. The data show that the mechanism of nucleotide binding to the 2D template is influenced by the chemistry of the bases and the pH,value of the solution. In a neutral solution of pH,7.5, the process is cooperative and selective with respect to Watson,Crick pairs (A,U and C,G), which form stable double planes in accordance with the Chargaff rule. In a more acidic solution at pH,6.0, the interactions between complementary partners become non-cooperative and the surface also stabilizes mismatched and wobble pairs due to the pH-induced changes in the receptor coordination state. The results suggest that hydrogen bonding plays a key role in the self-assembly of complementary nucleotides at the lipid-like interface, and the cooperative character of the process stems from the ideal matching of the orientation and chemistry of all the interacting components with respect to each other in neutral solution. [source] | |||||||||||||