Weak Trigger Research Articles

The Various Procoagulant Effects of PolyP Require Different Minimal Polymer Lengths.

Introduction: Polyphosphates (polyP) are negatively charged, linear phosphate polymers found throughout biology. PolyP in prokaryotes and unicellular eukaryotes is typically hundreds of phosphate units long, while polyP in dense granules of human platelets is ∼75 phosphates long. PolyP is secreted upon platelet activation, and we recently reported that it is a potent hemostatic regulator, acting at multiple points in the clotting cascade: PolyP triggers the contact pathway, accelerates factor V activation, and abrogates the anticoagulant function of tissue factor pathway inhibitor (TFPI). Our previous experiments utilized relatively heterodisperse polyP preparations. We have now isolated polyP fractions of defined polymer lengths and here report the size dependence of the various procoagulant effects of polyP.Methods: PolyP preparations were carefully size-fractionated by gel electrophoresis (Clark and Wood, Anal. Biochem. 1987, 161:280–290). Clotting assays were performed using pooled normal plasma with or without added recombinant TFPI or 40–50 μM polyP. Clotting was initiated by tissue factor (TF), factor Xa (FXa), or CaCl2 alone (contact pathway).Results: Of the polyP procoagulant activities tested, triggering the contact pathway required the longest polymers: We observed weak triggering of the contact pathway with ∼75mers and increasing procoagulant activity as polymer lengths increased, with maximal contact pathway activation requiring 450mers or longer. On the other hand, the downstream procoagulant effects of polyP required significantly shorter polyP polymers. (When clotting is triggered by either TF or FXa, further shortening of clotting times by polyP is attributed to accelerated factor V activation.) Minimum polymer lengths required to shorten TF or FXa clot times were ∼37mers, with maximal activity requiring 75mers or longer. Finally, the ability of polyP to abrogate TFPI anticoagulant function required the shortest minimum polymer lengths: Detectable anti-TFPI activity was observed with 11mers, with maximal activity requiring 49mers or longer.Conclusions: PolyP exhibited different minimum length requirements for its various procoagulant effects, consistent with the idea that polyP interacts with different proteins at various points in the clotting cascade. Contact pathway activation required very long polymers that were similar in size to those in infectious microorganisms. Therefore, triggering of the contact pathway by polyP may contribute to procoagulant/inflammatory responses to infection. In contrast, acceleration of factor V activation by polyP was maximal with polymers of the size released from human platelets. Even shorter polyP polymers abrogated TFPI function, suggesting that at least some of polyP's anti-TFPI effect may be mediated by mechanisms other than (or in addition to) its ability to accelerate factor V activation.

Two electromagnetically induced transparency windows and an enhanced electromagnetically induced transparency signal in a four-level tripod atomic system

We present the experimental observations and theoretical calculations of two electromagnetically induced transparency (EIT) windows and an enhanced EIT signal in a four-level tripod system of D1 line of 87Rb atoms. The two EIT dips produced by a strong coupling beam and a weak trigger beam were observed in the absorption spectrum of probe field, when the frequency detuning of the trigger beam was different from that of the coupling beam. When the frequency detuning of the trigger beam was near or equal to that of the coupling beam, the total depth of the EIT dip created by the coupling beam clearly became larger. The experimental measurements were in agreement with theoretical calculations.

Weak Triggers in Vowel Harmony

This paper examines vowel harmony initiated by a weak trigger. Height harmony in Veneto Italian dialects, wherein a post-tonic high vowel triggers raising of preceding mid vowels, forms a case study. Veneto presents two variable patterns: stress-targeted harmony, in which harmony propagates to the stressed syllable, and maximal extension harmony, in which raising persists to pretonic vowels. The conditions under which weak vowels trigger and control harmony are examined. It is argued that weak trigger harmony is motivated by perceptual disadvantage: harmony improves exposure of the spreading feature, accomplished either by extending to a stressed position or maximizing duration in the word. The apparent primacy of the vowel quality in weak position in Veneto is accounted for by markedness factors that independently prevent the stressed vowel from overriding it. In regard to positional privilege, it is argued that positional licensing (markedness) drives stress-targeted spreading – positional faithfulness cannot be responsible for strong targets. A weak trigger pattern emerges when licensing constraints operating over perceptually marked structure dominate positional faithfulness. Crosslinguistic applications are also explored.

A hypothetical mathematical construct explaining the mechanism of biological amplification in an experimental model utilizing picoTesla (PT) electromagnetic fields

We seek to answer the conundrum: What is the fundamental mechanism by which very weak, low frequency Electromagnetic fields influence biosystems? In considering the hydrophobicity of intramembranous protein (IMP) H-bonds which cross the phospholipid bilayer of plasma membranes, and the necessity for photonic recycling in cell surface interactions after dissipation of energetic states, present models lack structure and thermodynamic properties to maintain (Δ E) sufficient energy sources necessary for amplifications by factors of 10 12. Even though one accepts that the ligand–receptor association alters the conformation of extracellular, extruding portions of IMP’s at the cell surface, and that this change can be transmitted to the cytoplasm by the transmembranous helical segments by nonlinear vibrations of proteins with generation of soliton waves, one is still unable to account for repair and balanced function. Indeed, responses of critical molecules to certain magnetic field signals may include enhanced vibrational amplitudes, increased quanta of thermal energies and order inducing interactions. We may accept that microtrabecular reticulum-receptor is associated with actin filaments and ATP molecules which contribute to the activation of the cyclase enzyme system through piezoelectricity. Magnetic fields will pass through the membrane which sharply attenuates the electric field component of an EM field, due to its high impedance. Furthermore, EM oscillations are converted to mechanical vibrations; i.e., photon–phonon transduction, to induce molecular vibrations of frequencies specifically responsible for bioamplifications of weak triggers at the membrane surface, as well as GAP junctions. The hydrogen bonds of considerable importance are those in proteins (10 12 Hz) and DNA (10 11 Hz) and may be viewed as centers of EM radiation emission in the range from the mm microwaves to the far IR. However, classical electrodynamical theory does not yield a model for biomolecular resonant responses which are integrated over time and account for the connection between the phonon field and photons. Jacobson Resonance does supply an initial physical mechanism, as equivalencies in energy to that of Zeeman Resonance (i.e., zero-order magnetic resonance) and cyclotron resonance may be derived from the DeBroglie wave particle equation. For the first time, we view the introduction of Relativity Theory to biology in the expression, mc 2=BvLq, where m is the mass of a particle in the ‘box’ or ‘string’ (molecule in a biosystem), c is the velocity of electromagnetic field in space, independent of its inertial frame of reference, B is the magnetic flux density, v is the velocity of the carrier or ‘string’ (a one or two dimensional ‘box’) in which the particle exists, L is its dimension (length) and q represents a unit charge q=1 C, by defining electromotive force as energy per unit charge. Equivalencies suggest that qvBL is one of the fundamental expressions of energy of a charged wave-particle in magnetic fields, just as Zeeman and cyclotron resonance energy expressions, gβB and qhB/2π m, and is applicable to all charged particles (molecules in biological systems). There may exist spontaneous, independent and incessant interactions of magnetic vector B and particles in biosystems which exert Lorentz forces. Lorentz forces may be transmitted from EM field to gravitational field as a gravity wave which return to the phonon field as microgravitational fluctuations to therein produce quantum vibrational states that increase quanta of thermal energies integrated over time. This may account for the differential of 10 12 between photonic energy of ELF waves and the Boltzman energy kT. Recent data from in vivo controlled studies are included as empirical support for the various hypotheses presented.

Biological effects of electromagnetic fields.

Life on earth has evolved in a sea of natural electromagnetic (EM) fields. Over the past century, this natural environment has sharply changed with introduction of a vast and growing spectrum of man-made EM fields. From models based on equilibrium thermodynamics and thermal effects, these fields were initially considered too weak to interact with biomolecular systems, and thus incapable of influencing physiological functions. Laboratory studies have tested a spectrum of EM fields for bioeffects at cell and molecular levels, focusing on exposures at athermal levels. A clear emergent conclusion is that many observed interactions are not based on tissue heating. Modulation of cell surface chemical events by weak EM fields indicates a major amplification of initial weak triggers associated with binding of hormones, antibodies, and neurotransmitters to their specific binding sites. Calcium ions play a key role in this amplification. These studies support new concepts of communication between cells across the barriers of cell membranes; and point with increasing certainty to an essential physical organization in living matter, at a far finer level than the structural and functional image defined in the chemistry of molecules. New collaborations between physical and biological scientists define common goals, seeking solutions to the physical nature of matter through a strong focus on biological matter. The evidence indicates mediation by highly nonlinear, nonequilibrium processes at critical steps in signal coupling across cell membranes. There is increasing evidence that these events relate to quantum states and resonant responses in biomolecular systems, and not to equilibrium thermodynamics associated with thermal energy exchanges and tissue heating.

Cell membranes: The electromagnetic environment and cancer promotion

Use of weak electromagnetic fields to study the sequence and energetics of events that couple humoral stimuli from surface receptor sites to the cell interior has identified cell membranes as a primary site of interaction with these low frequency fields. Field modulation of cell surface chemical events indicates a major amplification of initial weak triggers associated with binding of hormones, antibodies and neurotransmitters to their specific binding sites. Calcium ions play a key role in this stimulus amplification, probably through highly cooperative alterations in binding to surface glycoproteins, with spreading waves of altered calcium binding across the membrane surface. Protein particles spanning the cell membrane form pathways for signaling and energy transfer. Fields millions of times weaker than the membrane potential gradient of 10(5) V/cm modulate cell responses to surface stimulating molecules. The evidence supports nonlinear, nonequilibrium processes at critical steps in transmembrane signal coupling. Powerful cancer-promoting phorbol esters act at cell membranes to stimulate ornithine decarboxylase which is essential for cell growth and DNA synthesis. This response is enhanced by weak microwave fields, also acting at cell membranes.

Characterization of the interaction of human eosinophils and neutrophils with opsonized particles.

The interaction of human eosinophils with opsonized particles was compared with that of human neutrophils. When eosinophils are stimulated with serum-opsonized zymosan particles, the lag time in H2O2 production is twice as long as found with neutrophils. Moreover, the concentration of these IgG + C3-coated particles required for optimal stimulation is about four times as high for eosinophils as for neutrophils. Under these conditions, the two cell types generate similar amounts of H2O2. However, eosinophils produce twice as much H2O2 as do neutrophils when stimulated with the soluble agent phorbol myristate acetate. Thus, although the oxidase capacity of eosinophils is larger than that of neutrophils, opsonized zymosan is a weak trigger for this activity in eosinophils. This phenomenon may be due to differences between the two cell types in the plasma membrane receptors or in the receptor oxidase transducing signal. The following are indications for the first possibility. i) IgG interacts poorly with the Fc gamma receptors on the eosinophil surface compared with those on neutrophils. This was shown by the inability of IgG-coated zymosan or IgG-coated latex to trigger any substantial H2O2 production by eosinophils unless brought into close contact with these cells by centrifugation. In contrast, neutrophils are stimulated by these particles both in suspension and in a pellet. The dissimilarity of the Fc gamma receptors on eosinophils and neutrophils was also shown with respect to antigenicity, determined by the monoclonal antibodies 3G8 and CLB-FcR-1. ii) Eosinophils contain about half as many receptors for C3b and C3bi on their surface as do neutrophils, also detected with monoclonal antibodies. The interaction of IgG subclasses with functional Fc gamma receptors on eosinophils and neutrophils showed that eosinophils release twice as much H2O2 as do neutrophils upon interaction with IgG1-, IgG2-, or IgG3-coated Sepharose beads, but this difference becomes fivefold with IgG4-coated Sepharose. This might be of relevance to the situation of chronic antigenic stimulation, e.g., in chronic schistosomiasis, in which eosinophil numbers and IgG4 antibody levels are elevated.

Trigger delay in whistler precursors

Detailed dispersion analysis of about thirty precursor events showed that the associated long whistlers traveled in the plasmasphere, at L ∼ 2.5–3.8, and probably in the same duct as their precursors. Measurement of the f, t trigger points of the precursors showed that the time of triggering (t) was generally more than halfway between the initiating lightning flashes and the associated two-hop whistlers by an amount (Δt) that generally decreased with trigger frequency (f). Because of apparent objections to triggering by hybrid whistlers, three alternative eplanations are investigated. Since all these are subject to serious objections, the hybrid explanation is re-examined. It is shown that the hybrid signal is expected to be quite weak (and hence rarely, if ever, observed) and that weak trigger signals should give, according to R. A. Helliwell's 1967 theory, both a delay and a frequency shift that account for the observed trigger points quite well.

Political Protest Songs and Actual Protest Values: Analysis of Fela’s “Sorrow, Tears & Blood” and Bob Marley’s “Stand up, Get up”

Political protest and songs have had inseparable relationship from time immemorial, but the Actual Protest Value of songs, that is, the exact aspects where songs exert their greatest influence in protest, are yet to attract high scholarly attention. This is what the current paper tries to locate through Fela Anikulapo Kuti's Sorrow, Tears and Blood and Bob Marley’s Stand up, Get up, using in-depth analysis of the songs' lyrics plus opinion survey of their listeners. Finding is that the actual protest values of the two songs are high in meditation upon protest problem and sustenance of ongoing protests, but very low in igniting protests on their own. Most people who listen to the two musicians' songs are mere fans of their music, not adherents of their lyrics. The analysis is used to explain the inability of Fela and Marley to ignite mass uprising in Africa through their many protest songs. The conclusion is that song is a weak trigger of protest, but it plays a very big role in sustaining resistance. Key words: Songs, Music, Protest, Actual Protest Value, Politics, Protest Songs.