Chapter 5. The simultaneous lenition of Spanish /ptk/ and /bdɡ/ as a chain shift in progress

2018 ◽  
pp. 95-120
Author(s):  
Christopher D. Eager
Keyword(s):  
A Chain

Observation of Atom Rows in Thorium Pyromellitate Using a Field Emission STEM

1977 ◽  
Vol 35 ◽  
pp. 80-81
Author(s):  
H. Todokoro ◽  
S. Nomura ◽  
T. Komoda
Keyword(s):  
Field Emission ◽  
Amorphous Carbon ◽  
Carbon Film ◽  
Dark Field Image ◽  
Dark Field ◽  
Amorphous Carbon Film ◽  
Atomic Size ◽  
Wide Range ◽  
A Chain

It is interesting to observe polymers at atomic size resolution. Some works have been reported for thorium pyromellitate by using a STEM (1), or a CTEM (2,3). The results showed that this polymer forms a chain in which thorium atoms are arranged. However, the distance between adjacent thorium atoms varies over a wide range (0.4-1.3nm) according to the different authors.The present authors have also observed thorium pyromellitate specimens by means of a field emission STEM, described in reference 4. The specimen was prepared by placing a drop of thorium pyromellitate in 10-3 CH3OH solution onto an amorphous carbon film about 2nm thick. The dark field image is shown in Fig. 1A. Thorium atoms are clearly observed as regular atom rows having a spacing of 0.85nm. This lattice gradually deteriorated by successive observations. The image changed to granular structures, as shown in Fig. 1B, which was taken after four scanning frames.

Time-Resolved Cryo-Electron Microscopy of Oscillating Microtubules

1990 ◽  
Vol 48 (1) ◽  
pp. 502-503
Author(s):  
Eva-Maria Mandelkow ◽  
Ron Milligan
Keyword(s):  
Electron Microscopy ◽  
Dynamic Instability ◽  
Entire Solution ◽  
Reaction Scheme ◽  
Time Resolved ◽  
X Ray ◽  
X Ray Scattering ◽  
A Chain ◽  
Ray Scattering

Microtubules form part of the cytoskeleton of eukaryotic cells. They are hollow libers of about 25 nm diameter made up of 13 protofilaments, each of which consists of a chain of heterodimers of α-and β-tubulin. Microtubules can be assembled in vitro at 37°C in the presence of GTP which is hydrolyzed during the reaction, and they are disassembled at 4°C. In contrast to most other polymers microtubules show the behavior of “dynamic instability”, i.e. they can switch between phases of growth and phases of shrinkage, even at an overall steady state [1]. In certain conditions an entire solution can be synchronized, leading to autonomous oscillations in the degree of assembly which can be observed by X-ray scattering (Fig. 1), light scattering, or electron microscopy [2-5]. In addition such solutions are capable of generating spontaneous spatial patterns [6].In an earlier study we have analyzed the structure of microtubules and their cold-induced disassembly by cryo-EM [7]. One result was that disassembly takes place by loss of protofilament fragments (tubulin oligomers) which fray apart at the microtubule ends. We also looked at microtubule oscillations by time-resolved X-ray scattering and proposed a reaction scheme [4] which involves a cyclic interconversion of tubulin, microtubules, and oligomers (Fig. 2). The present study was undertaken to answer two questions: (a) What is the nature of the oscillations as seen by time-resolved cryo-EM? (b) Do microtubules disassemble by fraying protofilament fragments during oscillations at 37°C?

Do Event-Related Brain Potentials Reflect Mental (Cognitive) Operations?

2002 ◽  
Vol 16 (3) ◽  
pp. 129-149 ◽  
Author(s):  
Boris Kotchoubey
Keyword(s):  
Cognitive Processes ◽  
Point Of View ◽  
Internal Variables ◽  
Brain Potentials ◽  
Cognitive Operations ◽  
External Variables ◽  
Series Of Experiments ◽  
Mental Operations ◽  
A Chain ◽  
Processing Mechanisms

Abstract Most cognitive psychophysiological studies assume (1) that there is a chain of (partially overlapping) cognitive processes (processing stages, mechanisms, operators) leading from stimulus to response, and (2) that components of event-related brain potentials (ERPs) may be regarded as manifestations of these processing stages. What is usually discussed is which particular processing mechanisms are related to some particular component, but not whether such a relationship exists at all. Alternatively, from the point of view of noncognitive (e. g., “naturalistic”) theories of perception ERP components might be conceived of as correlates of extraction of the information from the experimental environment. In a series of experiments, the author attempted to separate these two accounts, i. e., internal variables like mental operations or cognitive parameters versus external variables like information content of stimulation. Whenever this separation could be performed, the latter factor proved to significantly affect ERP amplitudes, whereas the former did not. These data indicate that ERPs cannot be unequivocally linked to processing mechanisms postulated by cognitive models of perception. Therefore, they cannot be regarded as support for these models.

Right-Hemisphere Specialization for Contour Grouping

2014 ◽  
Vol 61 (5) ◽  
pp. 331-339 ◽  
Author(s):  
Gregor Volberg
Keyword(s):  
Right Hemisphere ◽  
Contour Detection ◽  
Global Processing ◽  
Detection Accuracy ◽  
Frequency Spectra ◽  
Visual Hemifield ◽  
Spatial Frequencies ◽  
A Chain ◽  
The Right ◽  
Hemisphere Specialization

Previous studies often revealed a right-hemisphere specialization for processing the global level of compound visual stimuli. Here we explore whether a similar specialization exists for the detection of intersected contours defined by a chain of local elements. Subjects were presented with arrays of randomly oriented Gabor patches that could contain a global path of collinearly arranged elements in the left or in the right visual hemifield. As expected, the detection accuracy was higher for contours presented to the left visual field/right hemisphere. This difference was absent in two control conditions where the smoothness of the contour was decreased. The results demonstrate that the contour detection, often considered to be driven by lateral coactivation in primary visual cortex, relies on higher-level visual representations that differ between the hemispheres. Furthermore, because contour and non-contour stimuli had the same spatial frequency spectra, the results challenge the view that the right-hemisphere advantage in global processing depends on a specialization for processing low spatial frequencies.

A chain model for chromosomes

1961 ◽  
Vol 58 ◽  
pp. 1072-1077 ◽  
Author(s):  
Frank Stahl
Keyword(s):  
Chain Model ◽  
A Chain

Fibrinogen Montreal

1973 ◽  
Vol 29 (03) ◽  
pp. 536-546 ◽  
Author(s):  
M Lacombe ◽  
J Soria ◽  
C Soria ◽  
G d’Angelo ◽  
R Lavallee ◽  
...  
Keyword(s):  
Optical Density ◽  
Polyacrylamide Gel ◽  
Clotting Time ◽  
Functional Defect ◽  
A Chain ◽  
Fibrin Monomers

SummaryA new case of congenital dysfibrinogenemia characterized by a prolonged thrombin clotting time and a low optical density of the polymerization curve has been discovered in Montreal. The functional defect is due to an abnormal aggregation of fibrin monomers.The characteristics of this abnormal fibrinogen are serum gélification (Paracoagulation) at 37°, 22° and 4° C, a normal immuno-electrophoretic and electrofocusing pattern, a slight increase in the mobility in the α (A) chain by electrophoresis of the dissociated chains in polyacrylamide gel. However, no abnormality was found in the α (A) chain of the disulphide knot.

Observations on a Relationship between Steroid Metabolism and the Concentration of Plasma Fibrinogen

1963 ◽  
Vol 10 (02) ◽  
pp. 400-405 ◽  
Author(s):  
B. A Amundson ◽  
L. O Pilgeram
Keyword(s):  
Blood Coagulation ◽  
Methyl Ether ◽  
Broad Spectrum ◽  
Human Subjects ◽  
Plasma Fibrinogen ◽  
Steroid Metabolism ◽  
Specific Site ◽  
Chain Reaction ◽  
Normal Human ◽  
A Chain

SummaryEnovid (5 mg norethynodrel and 0.075 mg ethynylestradiol-3-methyl ether) therapy in young normal human subjects causes an increase in plasma fibrinogen of 32.4% (P >C 0.001). Consideration of this effect together with other effects of Enovid on the activity of specific blood coagulatory factors suggests that the steroids are exerting their effect at a specific site of the blood coagulation and/or fibrinolytic system. The broad spectrum of changes which are induced by the steroids may be attributed to a combination of a chain reaction and feed-back control.

Human Prothrombin Activation: Determination of Plasma and Serum Levels of Prothrombin Fragment 3 by Radioimmunoassay

1979 ◽  
Author(s):  
Daniel Walz ◽  
Thomas Brown
Keyword(s):  
Blood Clotting ◽  
Factor Xa ◽  
Heart Association ◽  
Serum Levels ◽  
Cross Reactivity ◽  
Assay Procedure ◽  
A Chain ◽  
Prothrombin Activation ◽  
Theoretical Amount

Human prothrombin activation is unique in that, in addition to the release of fragment 1.2 (FI.2) from the NH-terminus of prothrombin by factor Xa during the generation of thrombin, an additional 13 residue polypeptide, fragment 3 (F3), is autocatalytically removed from the amino-terminus of the thrombin A chain. We have developed a rapid radioimmunoassay for human F3 which incorporates short incubation times and the use of a preprecipitated second antibody; the assay can be performed in three hours. Specificity studies in buffer systems show prothrombin and prethrombin 1 cross-reacting at a level of 0.001; purified thrombin does not cross-react. In the presence of 5% BSA, prothrombin displays considerably less cross-reactivity. No immunoreactive material to F3 antibodies could be detected in 400 μL of plasma. Serum, obtained from whole blood clotting, contained measurable quantities of F3 (40-100 ng/mL). This amount in serum represents only 5-10% of the theoretical amount available should all of the fragment be hydrolytically cleaved during the conversion of prothrombin to thrombin. This assay procedure is currently being utilized to monitor the activation of purified human prothrombin in the absence and presence of selected plasma inhibitors. (Supported in part by NIH 05384-17 and the Michigan Heart Association).

Persuasion: Fellow Creatures

2017 ◽  
Author(s):  
Pam Morris
Keyword(s):  
The Self ◽  
The Novel ◽  
Class Relations ◽  
Narrative Perspective ◽  
Class Hierarchies ◽  
A Chain ◽  
Porous Boundaries

Persuasion overtly foregrounds the self as embodied: physical accidents and sickness are recurrent. Sir Walter Eliot’s belief in the time-defying bodily grace of nobility is subject to Austen’s harshest irony. The transition from vertically ordered place to horizontal space in Persuasion is more extreme than in any other of the completed novels. Anne Elliot’s movement from social exclusiveness to socially inclusive possibility allows Austen to challenge gender and class hierarchies traditionally held to be inborn. Her writerly experimentation expands the possibilities of narrative perspective to encompass the porous boundaries of the physical, the emotional and the rational that constitute any moment of consciousness. Her focalisation techniques in the text look directly towards Woolf’s stylist innovations. A chain of references to guns and shooting gathers into the novel contentious contemporary discursive networks on class relations, notions of masculinity and the nature of creaturely life.

Through the Lens of the Adam Narrative: A Re-consideration of Sūrat al-Baqara

2015 ◽  
Vol 17 (2) ◽  
pp. 24-46 ◽  
Author(s):  
M.O. Klar
Keyword(s):  
Present Article ◽  
Dominant Theme ◽  
Starting Point ◽  
Lexical Items ◽  
A Chain

The thesis of a single pillar or axis around which the longer Medinan suras are structured has been highly influential in the field of sura unity, and scholarship on the structure and coherence of Sūrat al-Baqara has tended to work towards charting the progress of a dominant theme throughout the textual blocks that make up the sura. In order to achieve this, scholars have divided the sura into discrete blocks; many have posited a chain of lexical and thematic links from one block to the next; some have concentrated solely on the hinges and borders between these suggested textual blocks. The present article argues that such methods, while often in themselves illuminating, are by their very nature reductive. As such they can result in the oversight of important elements of the sura. From a starting point of the Adam pericope provided in Q. 2:30–9, this study will focus on the recurrence of a number of its lexical items throughout Sūrat al-Baqara. By methodically tracing the passage of repeated, loosely Fall-related, vocabulary, it will attempt to widen the contextual lens through which the sura's textual blocks are viewed, and establish a broader perspective on its coherence. Via a discussion of the themes of ‘gardens’, ‘parable’, ‘prostration’, ‘covenant’, ‘wrongdoing’ and finally ‘blindness’, this article will posit ‘garments’, not as a structural pillar, but as a pivot around which many of the repeated lexical items of the sura rotate.

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