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Proper Functioning (proper + functioning)
Selected AbstractsAn antibody to synaptotagmin I facilitates synaptic transmissionEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2007Shao-Ying Hua Abstract Proper functioning of the nervous system requires precise control of neurotransmitter release. Synaptotagmin, a synaptic vesicle protein, is crucial for the temporal control of neurotransmitter release. The mechanism of synaptotagmin function is still under debate. To investigate the mechanism by which synaptotagmin controls neurotransmitter release, we injected an antibody of rat synaptotagmin I into a crayfish motor axon. We found that the antibody enhanced synaptic transmission at crayfish neuromuscular junctions by increasing the amplitude of the evoked synaptic response. This effect was antibody-dose dependent. The antibody also reduced the rise time of the synaptic potentials. These effects were accompanied by a reduction in the Hill coefficient for Ca2+ -dependence of synaptic transmission. Our findings support the hypothesis that synaptotagmin inhibits neurotransmitter release in the absence of Ca2+. [source] Acute toxicity of heavy metals to acetate-utilizing mixed cultures of sulfate-reducing bacteria: EC100 and EC50ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2001Vivek P. Utgikar Abstract Acid mine drainage from abandoned mines and acid mine pit lakes is an important environmental concern and usually contains appreciable concentrations of heavy metals. Because sulfate-reducing bacteria (SRB) are involved in the treatment of acid mine drainage, knowledge of acute metal toxicity levels for SRB is essential for the proper functioning of the treatment system for acid mine drainage. Quantification of heavy metal toxicity to mixed cultures of SRB is complicated by the confounding effects of metal hydroxide and sulfide precipitation, biosorption, and complexation with the constituents of the reaction matrix. The objective of this paper was to demonstrate that measurements of dissolved metal concentrations could be used to determine the toxicity parameters for mixed cultures of sulfate-reducing bacteria. The effective concentration, 100% (EC100), the lowest initial dissolved metal concentrations at which no sulfate reduction is observed, and the effective concentration, 50% (EC50), the initial dissolved metal concentrations resulting in a 50% decrease in sulfate reduction, for copper and zinc were determined in the present study by means of nondestructive, rapid physical and chemical analytical techniques. The reaction medium used in the experiments was designed specifically (in terms of pH and chemical composition) to provide the nutrients necessary for the sulfidogenic activity of the SRB and to preclude chemical precipitation of the metals under investigation. The toxicity-mitigating effects of biosorption of dissolved metals were also quantified. Anaerobic Hungate tubes were set up (at least in triplicate) and monitored for sulfate-reduction activity. The onset of SRB activity was detected by the blackening of the reaction mixture because of formation of insoluble ferrous sulfide. The EC100 values were found to be 12 mg/L for copper and 20 mg/L for zinc. The dissolved metal concentration measurements were effective as the indicators of the effect of the heavy metals at concentrations below EC100. The 7-d EC50 values obtained from the difference between the dissolved metal concentrations for the control tubes (tubes not containing copper or zinc) and tubes containing metals were found to be 10.5 mg/L for copper and 16.5 mg/L for zinc. Measurements of the turbidity and pH, bacterial population estimations by means of a most-probable number technique, and metal recovery in the sulfide precipitate were found to have only a limited applicability in these determinations. [source] The European Commission: The Limits of Centralization and the Perils of ParliamentarizationGOVERNANCE, Issue 3 2002Giandomenico MajoneArticle first published online: 17 DEC 200 The idea of an inevitable process of centralization in the European Community (EC)/European Union (EU) is a myth. Also, the metaphor of "creeping competences," with its suggestion of a surreptitious but continuous growth of the powers of the Commission, can be misleading. It is true that the functional scope of EC/EU competences has steadily increased, but the nature of new competences has changed dramatically, as may be seen from the evolution of the methods of harmonization. The original emphasis on total harmonization, which gives the Community exclusive competence over a given policy area, has been largely replaced by more flexible but less "communitarian" methods such as optional and minimum harmonization, reference to nonbinding technical standards, and mutual recognition. Finally, the treaties of Maastricht and Amsterdam explicitly excluded harmonization for most new competences. Thus, the expansion of the jurisdiction of the EC/EU has not automatically increased the powers of the Commission, but has actually weakened them in several respects. In addition, the progressive parliamentarization of the Commission risks compromising its credibility as an independent regulator, without necessarily enhancing its democratic legitimacy. Since the member states continue to oppose any centralization of regulatory powers, even in areas essential to the functioning of the internal market, the task of implementing Community policies should be entrusted to networks of independent national and European regulators, roughly modeled on the European System of Central Banks. The Commission would coordinate and monitor the activities of these networks in order to ensure the coherence of EC regulatory policies. More generally, it should bring its distinctive competence more clearly into focus by concentrating on the core business of ensuring the development and proper functioning of the single European market. This is a more modest role than that of the kernel of a future government of Europe, but it is essential to the credibility of the integration process and does not overstrain the limited financial and legitimacy resources available to the Commission. [source] Effects of cationic polymer on start-up and granulation in upflow anaerobic sludge blanket reactorsJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 3 2004Ying Wang Abstract The upflow anaerobic sludge blanket (UASB) has been used successfully to treat a variety of industrial wastewaters. It offers a high degree of organics removal, low sludge production and low energy consumption, along with energy production in the form of biogas. However, two major drawbacks are its long start-up period and deficiency of active biogranules for proper functioning of the process. In this study, the influence of a coagulant polymer on start-up, sludge granulation and the associated reactor performance was evaluated in four laboratory-scale UASB reactors. A control reactor (R1) was operated without added polymer, while the other three reactors, designated R2, R3 and R4, were operated with polymer concentrations of 5 mg dm,3, 10 mg dm,3 and 20 mg dm,3, respectively. Adding the polymer at a concentration of 20 mg dm,3 markedly reduced the start-up time. The time required to reach stable treatment at an organic loading rate (OLR) of 4.8 g COD dm,3 d,1 was reduced by more than 36% (R4) as compared with both R1 and R3, and by 46% as compared with R2. R4 was able to handle an OLR of 16 g COD dm,3 d,1 after 93 days of operation, while R1, R2 and R3 achieved the same loading rate only after 116, 116 and 109 days respectively. Compared with the control reactor, the start-up time of R4 was shortened by about 20% at this OLR. Granule characterization indicated that the granules developed in R4 with 20 mg dm,3 polymer exhibited the best settleability and methanogenic activity at all OLRs. The organic loading capacities of the reactors were also increased by the addition of polymer. The maximum organic loading of the control reactor (R1) without added polymer was 19.2 g COD dm,3 d,1, while the three polymer-assisted reactors attained a marked increase in organic loading of 25.6 g COD dm,3 d,1. Adding the cationic polymer could result in shortening of start-up time and enhancement of granulation, which may in turn lead to improvement in the efficiency of organics removal and loading capacity of the UASB system. Copyright © 2004 Society of Chemical Industry [source] The rpf gene of Micrococcus luteus encodes an essential secreted growth factorMOLECULAR MICROBIOLOGY, Issue 3 2002Galina V. Mukamolova Summary Micrococcus luteus secretes a small protein called Rpf, which has autocrine and paracrine signalling functions and is required for the resuscitation of dormant cells. Originally isolated from the supernatant of actively growing cultures, Rpf was also detected on the surface of actively growing bacteria. Most molecules may be sequestered non-productively at the cell surface, as a truncated form of the protein, encompassing only the ,Rpf domain' is fully active. The C-terminal LysM module, which probably mediates binding to the cell envelope, is not required for biological activity. Rpf was essential for growth of M. luteus. Washed cells, inoculated at low density into a minimal medium, could not grow in its absence. Moreover, the incorporation of anti-Rpf antibodies into the culture medium at the time of inoculation also prevented bacterial growth. We were unable to inactivate rpf using a disrupted form of the gene, in which most of the coding sequence was replaced with a selectable thiostrepton resistance marker. Gene disruption was possible in the presence of a second, functional, plasmid-located copy of rpf, but not in the presence of a rpf derivative whose protein product lacked the secretory signal sequence. As far as we are aware, Rpf is the first example of a truly secreted protein that is essential for bacterial growth. If the Rpf-like proteins elaborated by Mycobacterium tuberculosis and other mycobacteria prove similarly essential, interference with their proper functioning may offer novel opportunities for protecting against, and treating, tuberculosis and other mycobacterial disease. [source] Teaching & Learning Guide for: Moral Realism and Moral NonnaturalismPHILOSOPHY COMPASS (ELECTRONIC), Issue 3 2008Stephen Finlay Authors' Introduction Metaethics is a perennially popular subject, but one that can be challenging to study and teach. As it consists in an array of questions about ethics, it is really a mix of (at least) applied metaphysics, epistemology, philosophy of language, and mind. The seminal texts therefore arise out of, and often assume competence with, a variety of different literatures. It can be taught thematically, but this sample syllabus offers a dialectical approach, focused on metaphysical debate over moral realism, which spans the century of debate launched and framed by G. E. Moore's Principia Ethica. The territory and literature are, however, vast. So, this syllabus is highly selective. A thorough metaethics course might also include more topical examination of moral supervenience, moral motivation, moral epistemology, and the rational authority of morality. Authors Recommend: Alexander Miller, An Introduction to Contemporary Metaethics (Cambridge: Polity Press, 2003). This is one of the few clear, accessible, and comprehensive surveys of the subject, written by someone sympathetic with moral naturalism. David Brink, Moral Realism and the Foundations of Ethics (Cambridge: Cambridge University Press, 1989). Brink rehabilitates naturalism about moral facts by employing a causal semantics and natural kinds model of moral thought and discourse. Michael Smith, The Moral Problem (Oxford: Blackwell, 1994). Smith's book frames the debate as driven by a tension between the objectivity of morality and its practical role, offering a solution in terms of a response-dependent account of practical rationality. Gilbert Harman and Judith Jarvis Thomson, Moral Relativism & Moral Objectivity (Cambridge, MA: Blackwell, 1996). Harman argues against the objectivity of moral value, while Thomson defends it. Each then responds to the other. Frank Jackson, From Metaphysics to Ethics (Oxford: Clarendon Press, 1998). Jackson argues that reductive conceptual analysis is possible in ethics, offering a unique naturalistic account of moral properties and facts. Mark Timmons, Morality without Foundations (Oxford: Oxford University Press, 1999). Timmons distinguishes moral cognitivism from moral realism, interpreting moral judgments as beliefs that have cognitive content but do not describe moral reality. He also provides a particularly illuminating discussion of nonanalytic naturalism. Philippa Foot, Natural Goodness (New York, NY: Oxford University Press, 2001). A Neo-Aristotelian perspective: moral facts are natural facts about the proper functioning of human beings. Russ Shafer-Landau, Moral Realism: A Defence (New York, NY: Oxford University Press, 2003). In this recent defense of a Moorean, nonnaturalist position, Shafer-Landau engages rival positions in a remarkably thorough manner. Terence Cuneo, The Normative Web (New York, NY: Oxford University Press, 2007). Cuneo argues for a robust version of moral realism, developing a parity argument based on the similarities between epistemic and moral facts. Mark Schroeder, Slaves of the Passions (New York, NY: Oxford University Press, 2007). Schroeder defends a reductive form of naturalism in the tradition of Hume, identifying moral and normative facts with natural facts about agents' desires. Online Materials: PEA Soup: http://peasoup.typepad.com A blog devoted to philosophy, ethics, and academia. Its contributors include many active and prominent metaethicists, who regularly post about the moral realism and naturalism debates. Metaethics Bibliography: http://www.lenmanethicsbibliography.group.shef.ac.uk/Bib.htm Maintained by James Lenman, professor of philosophy at the University of Sheffield, this online resource provides a selective list of published research in metaethics. Stanford Encyclopedia of Philosophy: http://plato.stanford.edu See especially the entries under ,metaethics'. Sample Syllabus: Topics for Lecture & Discussion Note: unless indicated otherwise, all the readings are found in R. Shafer-Landau and T. Cuneo, eds., Foundations of Ethics: An Anthology (Malden: Blackwell, 2007). (FE) Week 1: Realism I (Classic Nonnaturalism) G. E. Moore, Principia Ethica, 2nd ed. (FE ch. 35). W. K. Frankena, ,The Naturalistic Fallacy,'Mind 48 (1939): 464,77. S. Finlay, ,Four Faces of Moral Realism', Philosophy Compass 2/6 (2007): 820,49 [DOI: 10.1111/j.1747-9991.2007.00100.x]. Week 2: Antirealism I (Classic Expressivism) A. J. Ayer, ,Critique of Ethics and Theology' (1952) (FE ch. 3). C. Stevenson, ,The Nature of Ethical Disagreement' (1963) (FE ch. 28). Week 3: Antirealism II (Error Theory) J. L. Mackie, ,The Subjectivity of Values' (1977) (FE ch. 1). R. Joyce, Excerpt from The Myth of Morality (2001) (FE ch. 2). Week 4: Realism II (Nonanalytic Naturalism) R. Boyd, ,How to be a Moral Realist' (1988) (FE ch. 13). P. Railton, ,Moral Realism' (1986) (FE ch. 14). T. Horgan and M. Timmons, ,New Wave Moral Realism Meets Moral Twin Earth' (1991) (FE ch. 38). Week 5: Antirealism III (Contemporary Expressivism) A. Gibbard, ,The Reasons of a Living Being' (2002) (FE ch. 6). S. Blackburn, ,How To Be an Ethical Anti-Realist' (1993) (FE ch. 4). T. Horgan and M. Timmons, ,Nondescriptivist Cognitivism' (2000) (FE ch. 5). W. Sinnott-Armstrong, ,Expressivism and Embedding' (2000) (FE ch. 37). Week 6: Realism III (Sensibility Theory) J. McDowell, ,Values and Secondary Qualities' (1985) (FE ch. 11). D. Wiggins, ,A Sensible Subjectivism' (1991) (FE ch. 12). Week 7: Realism IV (Subjectivism) & Antirealism IV (Constructivism) R. Firth, ,Ethical Absolutism and the Ideal Observer' (1952) (FE ch. 9). G. Harman, ,Moral Relativism Defended' (1975) (FE ch. 7). C. Korsgaard, ,The Authority of Reflection' (1996) (FE ch. 8). Week 8: Realism V (Contemporary Nonnaturalism) R. Shafer-Landau, ,Ethics as Philosophy' (2006) (FE ch. 16). T. M. Scanlon, What We Owe to Each Other (Cambridge, MA: Harvard University Press, 1998), ch. 1. T, Cuneo, ,Recent Faces of Moral Nonnaturalism', Philosophy Compass 2/6 (2007): 850,79 [DOI: 10.1111/j.1747-9991.2007.00102.x]. [source] Network board continuity and effectiveness of open innovation in Swedish strategic small-firm networksR & D MANAGEMENT, Issue 1 2009Joakim Wincent Increasing adoption of open innovation as an alternative route to research and development necessitates the development of new ways to organize innovation, as well as reassessment of existing ways. Much like traditional corporations that subscribe to the closed innovation paradigm, novel organizational arrangements targeting open innovation, such as small-firm networks, employ boards to effectively manage joint research-and-development activities. These boards are similar yet different from traditional corporate boards; as such, they may have different requirements for proper functioning. We use 5-year longitudinal data on 53 Swedish strategic small-firm networks to investigate how the boards should be organized to help improve the innovative status of network participants. We expand the set of tools available for effective organization of the boards' operations and emphasize the effects of network board continuity (rates of renewal) on network members' innovative performance. We argue that the relationship is curvilinear (U-shaped) and demonstrate that it is more pronounced in larger networks. [source] Natural and human dimensions of environmental change in the proximal reaches of Botswana's Okavango DeltaTHE GEOGRAPHICAL JOURNAL, Issue 1 2010HAMISAI HAMANDAWANA Though wetlands are vital for the proper functioning of terrestrial ecosystems and provisioning of a wide range of goods and services, their sustainability is being threatened by inappropriate human resource use practices due to our limited understanding of how these systems operate and lack of appropriately informed interventions. We attempt to address these limitations by using historical CORONA photographs of 1967, Landsat imagery of 1989, 1994 and 2001 and information from the literature to investigate the role of natural and human factors in influencing the direction of environmental change in the proximal reaches of Botswana's Okavango Delta. Results of this investigation point to fragmentation of natural habitats, localised degradation of areas close to perennial water supplies, significant increase in woody cover, significant decrease in open grassland, increase in scrub and shrubs, deterioration in the quality of grazing and depletion of specific woody species. With the direction of change pointing to persistent decrease in the environment's supporting potentials, there is urgent need to adopt intervention strategies potentially capable of enhancing sustainable utilisation of natural resources in this sub-region. [source] Physicochemical properties of thiol proteinase inhibitor isolated from goat pancreasBIOPOLYMERS, Issue 8 2010Medha Priyadarshini Abstract Thiol proteinase inhibitors are crucial to proper functioning of all living tissues consequent to their cathepsin regulatory and myriad important biologic properties. Equilibrium denaturation of dimeric goat pancreas thiol proteinase inhibitor (PTPI), a cystatin superfamily variant has been studied by monitoring changes in the protein's spectroscopic and functional characteristics. Denaturation of PTPI in guanidine hydrochloride and urea resulted in altered intrinsic fluorescence emission spectrum, diminished negative circular dichroism, and loss of its papain inhibitory potential. Native like spectroscopic properties and inhibitory activity are only partially restored when denaturant is diluted from guanidine hydrochloride unfolded samples demonstrating that process is partially reversible. Coincidence of transition curves and dependence of transition midpoint (3.2M) on protein concentration in guanidine hydrochloride-induced denaturation are consistent with a two-state model involving a native like dimer and denatured monomer. On the contrary, urea-induced unfolding of PTPI is a multiphasic process with indiscernible intermediates. The studies demonstrate that functional conformation and stability are governed by both ionic and hydrophobic interactions. © 2010 Wiley Periodicals, Inc. Biopolymers 93: 708,717, 2010. This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com [source] Molecular facets of sphingolipids: Mediators of diseasesBIOTECHNOLOGY JOURNAL, Issue 7 2009Fatma Betul Kavun Ozbayraktar Abstract Sphingolipids constitute a biologically active lipid class that is significantly important from both structural and regulatory aspects. The manipulation of sphingolipid metabolism is currently being studied as a novel strategy for cancer therapy. The basics of this therapeutic approach lie in the regulation property of sphingolipids on cellular processes, which are important in a cell's fate, such as cell proliferation, apoptosis, cell cycle arrest, senescence, and inflammation. Furthermore, the mutations in the enzymes catalyzing some specific reactions in the sphingolipid metabolism cause mortal lysosomal storage diseases like Fabry, Gaucher, Niemann-Pick, Farber, Krabbe, and Metachromatic Leukodystrophy. Therefore, the alteration of the sphingolipid metabolic pathway determines the choice between life and death. Understanding the sphingolipid metabolism and regulation is significant for the development of new therapeutic approaches for all sphingolipid-related diseases, as well as for cancer. An important feature of the sphingolipid metabolic pathway is the compartmentalization into endoplasmic reticulum, the Golgi apparatus, lysosome and plasma membrane, and this compartmentalization makes the transport of sphingolipids critical for proper functioning. This paper focuses on the structures, metabolic pathways, localization, transport mechanisms, and diseases of sphingolipids in Saccharomyces cerevisiae and humans, and provides the latest comprehensive information on sphingolipid research. [source] | ||||||||||||||||