Results for 'outer membrane exchange'

977 found
Order:
  1.  23
    The Fluidity of the Bacterial Outer Membrane Is Species Specific.Pengbo Cao & Daniel Wall - 2020 - Bioessays 42 (8):1900246.
    The outer membrane (OM) is an essential barrier that guards Gram‐negative bacteria from diverse environmental insults. Besides functioning as a chemical gatekeeper, the OM also contributes towards the strength and stiffness of cells and allows them to sustain mechanical stress. Largely influenced by studies of Escherichia coli, the OM is viewed as a rigid barrier where OM proteins and lipopolysaccharides display restricted mobility. Here the discussion is extended to other bacterial species, with a focus on Myxococcus xanthus. In (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  2.  44
    Na-Ca + K exchanger and Ca2+ homeostasis in retinal rod outer segments: Inactivation of the Ca2+ efflux mode and possible involvement of intracellular Ca2+ stores in Ca2+ homeostasis. [REVIEW]Paul P. M. Schnetkamp - 1995 - Behavioral and Brain Sciences 18 (3):488-488.
    Inactivation of the Ca2+ extrusion mode of the retinal rod Na- Ca + K exchanger is suggested to be the mechanism that prevents lowering of cytosolic free Ca2+ to < 1 nM when rod cells are saturated for a prolonged time under bright light conditions. Under these conditions, Ca2+ fluxes across disk membranes can contribute significantly to Ca2+ homeostasis in rods.
    Direct download (5 more)  
     
    Export citation  
     
    Bookmark  
  3.  22
    Tissue repair in myxobacteria: A cooperative strategy to heal cellular damage.Christopher N. Vassallo & Daniel Wall - 2016 - Bioessays 38 (4):306-315.
    Damage repair is a fundamental requirement of all life as organisms find themselves in challenging and fluctuating environments. In particular, damage to the barrier between an organism and its environment (e.g. skin, plasma membrane, bacterial cell envelope) is frequent because these organs/organelles directly interact with the external world. Here, we discuss the general strategies that bacteria use to cope with damage to their cell envelope and their repair limits. We then describe a novel damage‐coping mechanism used by multicellular myxobacteria. (...)
    Direct download (4 more)  
     
    Export citation  
     
    Bookmark   2 citations  
  4.  26
    Mitochondrial Outer Membrane Channels: Emerging Diversity in Transport Processes.Thomas Becker & Richard Wagner - 2018 - Bioessays 40 (7):1800013.
    Mitochondrial function and biogenesis depend on the transport of a large variety of proteins, ions, and metabolites across the two surrounding membranes. While several specific transporters are present in the inner membrane, transport processes across the outer membrane are less understood. Recent studies reveal that the number of outer membrane channels and their transport mechanisms are more diverse than originally thought. Four protein‐conducting channels promote transport of distinct sets of precursor proteins across and into the (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  5.  9
    Single‐molecule approaches reveal outer membrane protein biogenesis dynamics.Anna Svirina, Neharika Chamachi & Michael Schlierf - 2022 - Bioessays 44 (12):2200149.
    Outer membrane proteins (OMPs) maintain the viability of Gram‐negative bacteria by functioning as receptors, transporters, ion channels, lipases, and porins. Folding and assembly of OMPs involves synchronized action of chaperones and multi‐protein machineries which escort the highly hydrophobic polypeptides to their target outer membrane in a folding competent state. Previous studies have identified proteins and their involvement along the OMP biogenesis pathway. Yet, the mechanisms of action and the intriguing ability of all these molecular machines to (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  6.  17
    Novel Channels of the Outer Membrane of Mitochondria: Recent Discoveries Change Our View.Vanessa Checchetto & Ildiko Szabo - 2018 - Bioessays 40 (6):1700232.
    Ion channels mediate ion flux across biological membranes and regulate important organellar and cellular tasks. A recent study revealed the presence of four new proteins, the MIM complex (composed by Mim1 and Mim2), Ayr1, OMC7, and OMC8, that are able to form ion‐conducting channels in the outer mitochondria membrane (OMM). These findings strongly indicate that the OMM is endowed with many solute‐specific channels, in addition to porins and known channels mediating protein import into mitochondria. These solute‐specific channels provide (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  7.  37
    Lipoprotein Transport: Greasing the Machines of Outer Membrane Biogenesis.Marcin Grabowicz - 2018 - Bioessays 40 (4):1700187.
    The Gram-negative outer membrane is a potent permeability barrier against antibiotics, limiting clinical options amid mounting rates of resistance. The Lol transport pathway delivers lipoproteins to the OM. All the OM assembly machines require one or more OM lipoprotein to function, making the Lol pathway central for all aspects of OM biogenesis. The Lol pathways of many medically important species clearly deviate from the Escherichia coli paradigm, perhaps with implications for efforts to develop novel antibiotics. Moreover, recent work (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  8.  3
    Targeting and insertion of nuclear‐encoded preproteins into the mitochondrial outer membrane.Katsuyoshi Mihara - 2000 - Bioessays 22 (4):364-371.
    Most mitochondrial proteins are synthesized in the cytosol as preproteins with a cleavable presequence and are delivered to the import receptors on the mitochondria by cytoplasmic import factors. The proteins are then imported to the intramitochondrial compartments by the import systems of the outer and inner membranes, TOM and TIM. Mitochondrial outer membrane proteins are synthesized without a cleavable presequence and most of them contain hydrophobic transmembrane domains, which, in conjunction with the flanking segments, function as the (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  9.  5
    From How Do You Do, Dolores.Yoel Hoffmann & Michael Shkodnikov - 2024 - Common Knowledge 30 (2):213-223.
    Sometimes I think: I'm flying. And why am I flying? Because of the dress. The flesh, I think, is multiplying itself. Here are the children, I think, going away from me and coming to me. If all is one, I think, why this split?My body of thought is likewise made of a womb of wombs. Whatever it begets begets its own body [in this sense I may be said to be multiparous].I am beautiful like a snip of ivory. My face (...)
    No categories
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  10.  1
    The Tom channel in the mitochondrial outer membrane: alive and kicking.Gabrielle Bains & Trevor Lithgow - 1999 - Bioessays 21 (1):1-4.
  11.  39
    B Flach! B Flach!Myroslav Laiuk & Ali Kinsella - 2023 - Common Knowledge 29 (1):1-20.
    Don't tell terrible stories—everyone here has enough of their own. Everyone here has a whole bloody sack of terrible stories, and at the bottom of the sack is a hammer the narrator uses to pound you on the skull the instant you dare not believe your ears. Or to pound you when you do believe. Not long ago I saw a tomboyish girl on Khreshchatyk Street demand money of an elderly woman, threatening to bite her and infect her with syphilis. (...)
    No categories
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  12.  16
    How the Membrane Attack Complex Damages the Bacterial Cell Envelope and Kills Gram‐Negative Bacteria.Dennis J. Doorduijn, Suzan H. M. Rooijakkers & Dani A. C. Heesterbeek - 2019 - Bioessays 41 (10):1900074.
    The human immune system can directly lyse invading micro‐organisms and aberrant host cells by generating pores in the cell envelope, called membrane attack complexes (MACs). Recent studies using single‐particle cryoelectron microscopy have revealed that the MAC is an asymmetric, flexible pore and have provided a structural basis on how the MAC ruptures single lipid membranes. Despite these insights, it remains unclear how the MAC ruptures the composite cell envelope of Gram‐negative bacteria. Recent functional studies on Gram‐negative bacteria elucidate that (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  13.  19
    The dynamics of free cholesterol exchange may be critical for endothelial cell membranes in the brain.Frank D. Mann - 1990 - Perspectives in Biology and Medicine 33 (4):531.
  14.  16
    E.coli hemolysin interactions with prokaryotic and eukaryotic cell membranes.Colin Hughes, Peter Stanley & Vassilis Koronakis - 1992 - Bioessays 14 (8):519-525.
    The hemolysin toxin (HlyA) is secreted across both the cytoplasmic and outer membranes of pathogenic Escherichia coli and forms membrane pores in cells of the host immune system, causing cell dysfunction and death. The processes underlying the interaction of HlyA with the bacterial and mammalian cell membranes are remarkable. Secretion of HlyA occurs without a periplasmic intermediate and is directed by an uncleaved C‐terminal targetting signal and the HlyB and HlyD translocator proteins, the former being a member of (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  15.  16
    High frequency force generation in outer hair cells from the mammalian ear.Matthew Holley - 1991 - Bioessays 13 (3):115-120.
    Mammalian outer hair cells generate mechanical forces at acoustic frequencies and can thus amplify the sound stimulus within the inner ear. The mechanism of force generation depends upon the plasma membrane potential but not upon either calcium or ATP. Forces are generated in the lateral cortex along the full length of the cell. The cortex includes a two‐dimensional cytoskeletal lattice composed of circumferential filaments 6–7 nm thick that are cross‐linked by filaments 3–4 nm thick and 40–60 nm long. (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  16.  26
    Remedying Globalization and Consumerism: Joining the Inner and Outer Journeys in "Perfect Balance".Judith Simmer-Brown - 2002 - Buddhist-Christian Studies 22 (1):31-46.
    In lieu of an abstract, here is a brief excerpt of the content:Buddhist-Christian Studies 22 (2002) 31-46 [Access article in PDF] Remedying Globalization and Consumerism: Joining the Inner and Outer Journeys in "Perfect Balance" Judith Simmer-Brown Naropa University One hundred forty years ago, Abraham Lincoln wrote in a prophetic voice: I see in the near future a crisis approaching that unnerves me and causes me to tremble for the safety of my country.... Corporations have been enthroned and an era (...)
    Direct download (4 more)  
     
    Export citation  
     
    Bookmark  
  17.  21
    Zombie ideas about early endosymbiosis: Which entry mechanisms gave us the “endo” in different endosymbionts?Dave Speijer - 2021 - Bioessays 43 (7):2100069.
    Recently, a review regarding the mechanics and evolution of mitochondrial fission appeared in Nature. Surprisingly, it stated authoritatively that the mitochondrial outer membrane, in contrast with the inner membrane of bacterial descent, was acquired from the host, presumably during uptake. However, it has been known for quite some time that this membrane was also derived from the Gram‐negative, alpha‐proteobacterium related precursor of present‐day mitochondria. The zombie idea of the host membrane still surrounding the endosymbiont is (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark   4 citations  
  18.  31
    Functional Exposed Amino Acids of BauA as Potential Immunogen Against Acinetobacter baumannii.Hadise Bazmara, Abolfazl Jahangiri, Iraj Rasooli & Fatemeh Sefid - 2015 - Acta Biotheoretica 63 (2):129-149.
    Multidrug-resistant Acinetobacter baumannii is recognized to be among the most difficult antimicrobial-resistant gram negative bacilli to control and treat. One of the major challenges that the pathogenic bacteria face in their host is the scarcity of freely available iron. To survive under such conditions, bacteria express new proteins on their outer membrane and also secrete iron chelators called siderophores. Antibodies directed against these proteins associated with iron uptake exert a bacteriostatic or bactericidal effect against A. baumanii in vitro, (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  19.  21
    Genetics of surface protein variation in Neisseria gonorrhoeae.George L. Murphy & Janne G. Cannon - 1988 - Bioessays 9 (1):7-11.
    Neisseria gonorrhoeae, the bacterium that causes the sexually transmitted disease gonorrhea, demonstrates extensive antigenic heterogeneity in its surface components. The organism has the capacity to switch on and off the synthesis of different versions of components such as pili, outer membrane proteins, and lipopolysaccharide. Recent studies have shown that the gonococcus uses novel and complex mechanisms, of types not described previously, to store different versions of genetic information for surface proteins, and to regulate expression of those genes.
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  20.  18
    The secretion pathway of IgA protease‐type proteins in gram‐negative bacteria.Thomas Klauser, Johannes Pohlner & Thomas F. Meyer - 1993 - Bioessays 15 (12):799-805.
    The pathogenic, Gram‐negative bacteria, Neisseria gon‐orrhoeae, Neisseria meningitidis and Haemophilus influenzae, secrete immunoglobulin A1 proteases into their extracellular surroundings. An extraordinary feature in the secretory pathway of these putative virulence factors is a self‐directed outer membrane transport step allowing the proteins to be secreted autonomously, even from foreign Gram‐negative host cells like Escherichia coli. Here we summarize recent achievements in the understanding of IgA protease outer membrane translocation.
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  21.  10
    Becoming a Cyclist.Steen Nepper Larsen - 2010-09-24 - In Fritz Allhoff, Jesús Ilundáin‐Agurruza & Michael W. Austin (eds.), Cycling ‐ Philosophy for Everyone. Wiley‐Blackwell. pp. 27–38.
    This chapter contains sections titled: Phenomenological Reflections on Cycling Extended Embodiment – Cycling Thoughts Campagnolo Ti Amo (I Love You) A Multiple Bombardment of the Senses Settling of Accounts – In the Long Run It Is Impossible to Cheat Cycle Speech A Trembling Experience A Descent – Living Up to Its Reputation A Collective Shiver Notes.
    No categories
    Direct download  
     
    Export citation  
     
    Bookmark   2 citations  
  22.  22
    Problems And Paradigms: Golgi complex beads and the transition region.Michael Locke - 1990 - Bioessays 12 (10):495-501.
    Secretory proteins and membranes move in transfer vesicles from the rough endoplasmic reticulum through the transitional region to the outer saccule of the Golgi complex. In both arthropod and vertebrate cells, the GC beads are a characteristic structural component of the transitional region. The beads are particles about half the size of ribosomes arranged equidistantly from one another and the smooth face of the ER. In an active GC, the beads are in rings through which the ER membrane (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  23.  16
    How depolymerization can promote polymerization: the case of actin and profilin.Elena G. Yarmola & Michael R. Bubb - 2009 - Bioessays 31 (11):1150-1160.
    Rapid polymerization and depolymerization of actin filaments in response to extracellular stimuli is required for normal cell motility and development. Profilin is one of the most important actin‐binding proteins; it regulates actin polymerization and interacts with many cytoskeletal proteins that link actin to extracellular membrane. The molecular mechanism of profilin has been extensively considered and debated in the literature for over two decades. Here we discuss several accepted hypotheses regarding the mechanism of profilin function as well as new recently (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  24.  68
    Relying on Your Own Voice.Charles L. Griswold Jr - 1999 - Review of Metaphysics 53 (2):283-307.
    PLATO’S Protagoras is composed of three distinct frames. The outer frame consists in Socrates’ brief discussion with an unnamed companion. The remainder of the Protagoras is willingly narrated by Socrates to the companion, from memory of course, and apparently right after the main action. The inner frame consists in Socrates’ dialogue with Hippocrates. Roused before dawn by the impetuous young man, Socrates leads Hippocrates to reflect on the wisdom of his enthusiastic desire to study with Protagoras. This is a (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark   6 citations  
  25.  37
    Structure‐guided insights on the role of NS1 in flavivirus infection.David L. Akey, W. Clay Brown, Joyce Jose, Richard J. Kuhn & Janet L. Smith - 2015 - Bioessays 37 (5):489-494.
    We highlight the various domains of the flavivirus virulence factor NS1 and speculate on potential implications of the NS1 3D structure in understanding its role in flavivirus pathogenesis. Flavivirus non‐structural protein 1 (NS1) is a virulence factor with dual functions in genome replication and immune evasion. Crystal structures of NS1, combined with reconstructions from electron microscopy (EM), provide insight into the architecture of dimeric NS1 on cell membranes and the assembly of a secreted hexameric NS1‐lipid complex found in patient sera. (...)
    Direct download (4 more)  
     
    Export citation  
     
    Bookmark   1 citation  
  26.  28
    Embryo research--why the Cardinal is wrong. Walton - 1990 - Journal of Medical Ethics 16 (4):185-186.
    Reasons are given for suggesting that individuation of the human embryo does not begin until the primitive streak forms at about the fourteenth day after conception; this view, though contested by many, is held by very many committed Christians of all denominations. In the conceptus or pre-embryo, after the formation of a blastocyst at about four-five days after fertilisation, biopsy of a single cell from the outer layer of cells (which later can form the membranes and placenta) can be (...)
    Direct download (7 more)  
     
    Export citation  
     
    Bookmark  
  27.  1
    Phagocytosis by the retinal pigment epithelium: New insights into polarized cell mechanics.Ceniz Zihni - 2025 - Bioessays 47 (1):2300197.
    The retinal pigment epithelium (RPE) is a specialized epithelium at the back of the eye that carries out a variety of functions essential for visual health. Recent studies have advanced our molecular understanding of one of the major functions of the RPE; phagocytosis of spent photoreceptor outer segments (POS). Notably, a mechanical link, formed between apical integrins bound to extracellular POS and the intracellular actomyosin cytoskeleton, is proposed to drive the internalization of POS. The process may involve a “nibbling” (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  28.  28
    Alternating terminal electron-acceptors at the basis of symbiogenesis: How oxygen ignited eukaryotic evolution.Dave Speijer - 2017 - Bioessays 39 (2):1600174.
    What kind of symbiosis between archaeon and bacterium gave rise to their eventual merger at the origin of the eukaryotes? I hypothesize that conditions favouring bacterial uptake were based on exchange of intermediate carbohydrate metabolites required by recurring changes in availability and use of the two different terminal electron chain acceptors, the bacterial one being oxygen. Oxygen won, and definitive loss of the archaeal membrane potential allowed permanent establishment of the bacterial partner as the proto‐mitochondrion, further metabolic integration (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark   11 citations  
  29.  3
    New insights into the mechanism for clearance of apoptotic cells.Udo K. Messmer & Josef Pfeilschifter - 2000 - Bioessays 22 (10):878-881.
    Apoptosis is a physiological mechanism for the removal of unwanted or damaged cells. Apoptotic cells are rarely seen in living tissues, however, because of their rapid and efficient removal by phagocytosis. Phagocytotic cells such as macrophages or dendritic cells recognize apoptotic cells by specific changes of cell surface markers, which usually are not present on normal cells. One such event is the exposure of phosphatidylserine, which moves from the plasma membrane inner leaflet to the outer leaflet in preapoptotic (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark   1 citation  
  30.  19
    Nuclear envelope budding: Getting large macromolecular complexes out of the nucleus.Kevin C. Sule, Mitsutoshi Nakamura & Susan M. Parkhurst - 2024 - Bioessays 46 (2):2300182.
    Transport of macromolecules from the nucleus to the cytoplasm is essential for nearly all cellular and developmental events, and when mis‐regulated, is associated with diseases, tumor formation/growth, and cancer progression. Nuclear Envelope (NE)‐budding is a newly appreciated nuclear export pathway for large macromolecular machineries, including those assembled to allow co‐regulation of functionally related components, that bypasses canonical nuclear export through nuclear pores. In this pathway, large macromolecular complexes are enveloped by the inner nuclear membrane, transverse the perinuclear space, and (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  31.  58
    Support vector machines for predicting apoptosis proteins types.Jing Huang & Feng Shi - 2005 - Acta Biotheoretica 53 (1):39-47.
    Apoptosis proteins have a central role in the development and homeostasis of an organism. These proteins are very important for understanding the mechanism of programmed cell death, and their function is related to their types. According to the classification scheme by Zhou and Doctor (2003), the apoptosis proteins are categorized into the following four types: (1) cytoplasmic protein; (2) plasma membrane-bound protein; (3) mitochondrial inner and outer proteins; (4) other proteins. A powerful learning machine, the Support Vector Machine, (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark   2 citations  
  32.  27
    Recoverin, a calcium-binding protein in photoreceptors.James B. Hurley - 1995 - Behavioral and Brain Sciences 18 (3):497-498.
    Recoverin is a Ca2+-binding protein found primarily in vertebrate photoreceptors. The proposed physiological function of recoverin is based on the finding that recoverin inhibits light-stimulated phosphorylation of rhodopsin. Recoverin interacts with rod outer segment membranes in a Ca2+-dependent manner. This interaction requires N-terminal acylation of recoverin. Four types of fatty acids have been detected on the N-terminus of recoverin, but the functional significance of this heterogeneous acylation is not yet clear.
    Direct download (5 more)  
     
    Export citation  
     
    Bookmark  
  33.  23
    Does cholesterol use the mitochondrial contact site as a conduit to the steroidogenic pathway?Murray Thomson - 2003 - Bioessays 25 (3):252-258.
    The first and rate‐limiting step of steroidogenesis is the transfer of cholesterol from the outer mitochondrial membrane to the inner membrane where it is converted to pregnenolone by cytochrome P450 side‐chain cleavage (P450scc). This reaction is modulated in the gonads and adrenals by the steroidogenic acute regulatory protein (StAR), however, the mechanism used by StAR is not understood. The outer and inner mitochondrial membranes are joined at contact sites that are thought to be held in place (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  34.  25
    Synthetic cells and organelles: compartmentalization strategies.Renée Roodbeen & Jan C. M. van Hest - 2009 - Bioessays 31 (12):1299-1308.
    The recent development of RNA replicating protocells and capsules that enclose complex biosynthetic cascade reactions are encouraging signs that we are gradually getting better at mastering the complexity of biological systems. The road to truly cellular compartments is still very long, but concrete progress is being made. Compartmentalization is a crucial natural methodology to enable control over biological processes occurring within the living cell. In fact, compartmentalization has been considered by some theories to be instrumental in the creation of life. (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark   1 citation  
  35. Competing ways of life and ring-composition in NE x 6-8.Thornton Lockwood - 2014 - In Ronald Polansky (ed.), The Cambridge Companion to Aristotle's Nicomachean Ethics. New York, New York: Cambridge University Press. pp. 350-369.
    The closing chapters of Aristotle’s Nicomachean Ethics x are regularly described as “puzzling,” “extremely abrupt,” “awkward,” or “surprising” to readers. Whereas the previous nine books described—sometimes in lavish detail—the multifold ethical virtues of an embodied person situated within communities of family, friends, and fellow-citizens, NE x 6-8 extol the rarified, god-like and solitary existence of a sophos or sage (1179a32). The ethical virtues that take up approximately the first half of the Ethics describe moral exempla who experience fear fighting for (...)
    Direct download  
     
    Export citation  
     
    Bookmark   2 citations  
  36. Haack’s foundherentism is a foundationalism.Peter Tramel - 2008 - Synthese 160 (2):215-228.
    Susan Haack has always maintained that her unquestionably important foundherentist theory of epistemic justification is not a foundationalism. In a 1997 "Synthese" exchange, Laurence BonJour questioned her right to this claim, and she dug in and defended it. What was at stake is of timeless importance to epistemology: it goes directly to the question, "What is foundationalism?" I inquire with greater care than either Haack or BonJour took in 1997, and I find decisively in favor of the view that (...)
    Direct download (4 more)  
     
    Export citation  
     
    Bookmark   4 citations  
  37.  79
    Möbius transformation and conformal relativity.Reijo Piirainen - 1996 - Foundations of Physics 26 (2):223-242.
    The Möbius transformation (MT) was analyzed as a coordinate transformation in the Minkowski form. The transformation function contains three separate light cones. The Weyl spheres were interpreted as basic constituents of local light cones. These cones are related to the denominators of the MT and its inverse, and their apexes define an axis with the top of the global light cone as the centerpoint. That axis represents the local part of the world-line of a moving frame of reference. On the (...)
    Direct download (3 more)  
     
    Export citation  
     
    Bookmark   1 citation  
  38.  41
    Cybersemiotic Pragmaticism and Constructivism.S. Brier - 2009 - Constructivist Foundations 5 (1):19 - 39.
    Context: Radical constructivism claims that we have no final truth criteria for establishing one ontology over another. This leaves us with the question of how we can come to know anything in a viable manner. According to von Glasersfeld, radical constructivism is a theory of knowledge rather than a philosophy of the world in itself because we do not have access to a human-independent world. He considers knowledge as the ordering of experience to cope with situations in a satisfactory way. (...)
    Direct download  
     
    Export citation  
     
    Bookmark   20 citations  
  39.  20
    Late endosomal and lysosomal trafficking during integrin‐mediated cell migration and invasion.Elena Rainero & Jim C. Norman - 2013 - Bioessays 35 (6):523-532.
    Recently it has become clear that trafficking of integrins to late endosomes is key to the regulation of integrin expression and function during cell migration. Here we discuss the molecular machinery that dictates whether integrins are sorted to recycling endosomes or are targeted to late endosomes and lysosomes. Integrins and other receptors that are sorted to late endosomes are not necessarily degraded and, under certain circumstances, can be spared destruction and returned to the cell surface to drive cell migration and (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  40.  15
    The molecular and cell biology of anion transport by bacteria.Peter C. Maloney - 1992 - Bioessays 14 (11):757-762.
    This article summarizes the study of anion exchange mechanisms in bacteria. Along with defining at least two different families of anion exchange, an examination of such carrier‐mediated antiport reactions has led to techniques that considerably broaden the scope of biochemical methods for examining membrane proteins. Such advances have been exploited to show that anion exchange itself forms the mechanistic base of an entirely new kind of proton pump, one which may shed light on a variety of (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark   1 citation  
  41.  59
    Beliefs about evolution, mind, nature, and society: Excerpts from an interview with Ervin Laszlo.Joseph H. Schaeffer - 1988 - Zygon 23 (2):171-192.
    Fundamental questions arise in every age, questions such as those concerning the individual in society, social order, labor and exchange, meaning and ethics, and spiritual life and values. In addressing these questions Ervin Laszlo emphasizes insight and understanding, the mutability and flexibility of knowledge, cultural diversity and organizational interdependence, and harmony in nature. General Systems Theory and a theory of general evolution provide the framework for his thinking. He asks that as human beings we assume responsibility for creative, reasoned, (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  42.  15
    Abelard's Historia Calamitatum and Letters: Self as Search and Struggle.Eileen Sweeney - 2007 - Poetics Today 28 (2):303-336.
    In this essay, I offer an interpretation of Abelard's Historia Calamitatum and letters exchanged with Heloise, arguing that both are informed by the attempt to look below the surfaces of language, self, and action to a reality beneath and to achieve authenticity, by which I mean coherence between surface and depth. This reading shows an emerging sense of self and self-knowledge based on the relationship between external act and internal intention. While using traditional medieval narrative forms, I argue, Abelard gives (...)
    Direct download  
     
    Export citation  
     
    Bookmark  
  43.  13
    Enviro-Friendly Hydrogen Generation From Steel Mill-Scale via Metal-Steam Reforming.Sathees Kesavan & Abdul-Majeed Azad - 2006 - Bulletin of Science, Technology and Society 26 (4):305-313.
    An economically viable and environmental friendly method of generating hydrogen for fuel cells is by the reaction of certain metals with steam, called metalsteam reforming (MSR). This technique does not generate any toxic by-products nor contributes to the undesirable greenhouse effect. From the standpoint of favorable thermodynamics, total environmental benignity, and attractive economics, iron appears to be the metal of choice for such a process. An inexpensive source of iron for the MSR is the steel industry's mill-scale waste via hydrogen (...)
    No categories
    Direct download  
     
    Export citation  
     
    Bookmark  
  44.  42
    Apologii︠a︡ Sofistov: Reli︠a︡tivizm Kak Ontologicheskai︠a︡ Sistema.Igorʹ Nikolaevich Rassokha - 2009 - Kharʹkov: Kharkivsʹka Nat͡sionalʹna Akademii͡a Misʹkoho Hospodarstva.
    Sophists’ apologia. -/- Sophists were the first paid teachers ever. These ancient Greek enlighteners taught wisdom. Protagoras, Antiphon, Prodicus, Hippias, Lykophron are most famous ones. Sophists views and concerns made a unified encyclopedic system aimed at teaching common wisdom, virtue, management and public speaking. Of the contemporary “enlighters”, Deil Carnegy’s educational work seems to be the most similar to sophism. Sophists were the first intellectuals – their trade was to sell knowledge. They introduced a new type of teacher-student relationship – (...)
    No categories
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  45.  52
    Modelling of the coupling between brain electrical activity and metabolism.Agnès Aubert, Robert Costalat & Romain Valabrègue - 2001 - Acta Biotheoretica 49 (4):301-326.
    In order to make an attempt at grouping the various aspects of brain functional imaging (fMRI, MRS, EEG-MEG, ...) within a coherent frame, we implemented a model consisting of a system of differential equations, that includes: (1) sodium membrane transport, (2) Na/K ATPase, (3) neuronal energy metabolism (i.e. glycolysis, buffering effect of phosphocreatine, and mitochondrial respiration), (4) blood-brain barrier exchanges and (5) brain hemodynamics, all the processes which are involved in the activation of brain areas. We assumed that the (...)
    Direct download  
     
    Export citation  
     
    Bookmark   2 citations  
  46.  30
    Signaling, mitogenesis and the cytoskeleton: Where the action is.Kermit L. Carraway & Coralie A. Carothers Carraway - 1995 - Bioessays 17 (2):171-175.
    Stimulation of mitogenesis by the epidermal growth factor (EGF) operates through a pathway involving the receptor, the small G‐protein Ras and protein kinases of the MAP kinase cascade. It is proposed that two of the critical steps of that pathway utilize localization of components to the plasma membrane where Ras is located: recruitment of the nucleotide exchange protein Sos to the phosphorylated EGF receptor via a complex with the SH2/SH3‐containing protein Grb2 and recruitment of the protein kinase Raf (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark   3 citations  
  47.  43
    An introduction to Neopoetics.Heather Raikes - 2012 - Technoetic Arts 9 (2-3):285-292.
    Neopoetics is a matrix for dynamic perceptual convergences between material and immaterial systems. The deep foundational ground for Neopoetics is the Poetics of Aristotle and its relation to the ancient Greek theatre as a practical systemic ideology for the mythic Greek drama. As Aristotle’s Poetics posits six basic components for the construction of drama (plot, character, thought, diction, song and spectacle) the neopoetic system has six constituent aspects: expanded embodiment, experiential metaphor, matrix architecture, perceptual resonance, the rheomode and neopoetic mythos. (...)
    Direct download (5 more)  
     
    Export citation  
     
    Bookmark  
  48. McDowell's germans: Response to 'on Pippin's postscript'.Robert B. Pippin - 2007 - European Journal of Philosophy 15 (3):411–434.
    As McDowell makes clear in ‘On Pippin’s Postscript’ and in many other works, the interpretive question at issue in this exchange—how to understand the relation between Kant and Hegel, especially as that concerns Kant’s central ‘Deduction’ argument in the Critique of Pure Reason1—brings into the foreground an even larger problem on which all the others depend: the right way to understand at the highest level of generality the relation between active or spontaneous thought and our receptive and corporeal sensibility (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark   4 citations  
  49.  15
    Dynamic organisation of intermediate filaments and associated proteins during the cell cycle.Roland Foisner - 1997 - Bioessays 19 (4):297-305.
    Intermediate filaments, which form the structural framework of both the cytoskeleton and the nuclear lamina in most eukaryotic cells, have been found to be highly dynamic structures. A continuous exchange of subunit proteins at the filament surface and a stabilisation of soluble subunits by chaperone‐type proteins may modulate filament structure and plasticity. Recent studies on the cell cycle‐dependent interaction of intermediate filaments with associated proteins, and a detailed analysis of intermediate filament phosphorylation in defined subcellular locations at various stages (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
  50.  17
    Cell fate transitions during stomatal development.Laura Serna - 2009 - Bioessays 31 (8):865-873.
    Stomata, the most influential components in gas exchange with the atmosphere, represent a revealing system for studying cell fate determination. Studies in Arabidopsis thaliana have demonstrated that many of the components, functioning in a signaling cascade, guide numerous cell fate transitions that occur during stomatal development. The signaling cascade is initiated at the cell surface through the activation of the membrane receptors TOO MANY MOUTHS (TMM) and/or ERECTA (ER) family members by the secretory peptide EPIDERMAL PATTERNING FACTOR1 (EPF1) (...)
    Direct download (2 more)  
     
    Export citation  
     
    Bookmark  
1 — 50 / 977