Relevant bibliographies by topics / Contraction

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Contraction'

Author: Grafiati
Published: 4 June 2021
Last updated: 30 July 2024

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Journal articles on the topic "Contraction"

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Hogan, Michael C., Erica Ingham, and S. Sadi Kurdak. "Contraction duration affects metabolic energy cost and fatigue in skeletal muscle." American Journal of Physiology-Endocrinology and Metabolism 274, no. 3 (March 1, 1998): E397—E402. http://dx.doi.org/10.1152/ajpendo.1998.274.3.e397.

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It has been suggested that during a skeletal muscle contraction the metabolic energy cost at the onset may be greater than the energy cost related to holding steady-state force. The purpose of the present study was to investigate the effect of contraction duration on the metabolic energy cost and fatigue process in fully perfused contracting muscle in situ. Canine gastrocnemius muscle ( n = 6) was isolated, and two contractile periods (3 min of isometric, tetanic contractions with 45-min rest between) were conducted by each muscle in a balanced order design. The two contractile periods had stimulation patterns that resulted in a 1:3 contraction-to-rest ratio, with the difference in the two contractile periods being in the duration of each contraction: short duration 0.25-s stimulation/0.75-s rest vs. long duration 1-s stimulation/3-s rest. These stimulation patterns resulted in the same total time of stimulation, number of stimulation pulses, and total time in contraction for each 3-min period. Muscle O2 uptake, the fall in developed force (fatigue), the O2 cost of developed force, and the estimated total energy cost (ATP utilization) of developed force were significantly greater ( P < 0.05) with contractions of short duration. Lactate efflux from the working muscle and muscle lactate concentration were significantly greater with contractions of short duration, such that the calculated energy derived from glycolysis was three times greater in this condition. These results demonstrate that contraction duration can significantly affect both the aerobic and anaerobic metabolic energy cost and fatigue in contracting muscle. In addition, it is likely that the greater rate of fatigue with more rapid contractions was a result of elevated glycolytic production of lactic acid.
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Conley, Kevin E., and Stan L. Lindstedt. "Energy-saving mechanisms in muscle: the minimization strategy." Journal of Experimental Biology 205, no. 15 (August 1, 2002): 2175–81. http://dx.doi.org/10.1242/jeb.205.15.2175.

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SUMMARYMany mechanisms reduce the cost of muscle activity. Here, we describe a set of specializations that reduce the cost of contraction in the high-frequency twitches that are used by a wide variety of animals for either sound production or flight. Minimizing the cost of these contractions means that cellular ATP production can meet ATP demand and sustain the high contractile rate. Two classes of specialization are found that minimize the contractile cost. The first class reduces the muscle work required per contraction. Light appendages such as rattles, insect limbs and membranous wings that require little work for movement are used in high-frequency contractions. The second set of specializations involves processes that minimize energy use. High-frequency muscles tend to have a lower cross-bridge content, fewer attached cross-bridges and shorter length changes per contraction. The result is low muscle-specific forces (stress), small length changes (strain) and rapid contraction times that suggest that these muscles push the lower limit of contractile function. The consequence of function at this lower extreme of contraction is to minimize the contractile cost of high-frequency muscles. Thus, specializations that permit rapid contractions at a low rate of ATP use per twitch are the basis of a minimization strategy for energy saving in muscles contracting at high frequency.
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Hogan, Michael C., Bruno Grassi, Michele Samaja, Creed M. Stary, and L. B. Gladden. "Effect of contraction frequency on the contractile and noncontractile phases of muscle venous blood flow." Journal of Applied Physiology 95, no. 3 (September 2003): 1139–44. http://dx.doi.org/10.1152/japplphysiol.00226.2003.

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The purpose of this study was to test the hypothesis that increasing muscle contraction frequency, which alters the duty cycle and metabolic rate, would increase the contribution of the contractile phase to mean venous blood flow in isolated skeletal muscle during rhythmic contractions. Canine gastrocnemius muscle ( n = 5) was isolated, and 3-min stimulation periods of isometric, tetanic contractions were elicited sequentially at rates of 0.25, 0.33, and 0.5 contractions/s. The O2 uptake, tension-time integral, and mean venous blood flow increased significantly ( P < 0.05) with each contraction frequency. Venous blood flow during both the contractile (106 ± 6, 139 ± 8, and 145 ± 8 ml·100 g-1·min-1) and noncontractile phases (64 ± 3, 78 ± 4, and 91 ± 5 ml·100 g-1·min-1) increased with contraction frequency. Although developed force and duration of the contractile phase were never significantly different for a single contraction during the three contraction frequencies, the amount of blood expelled from the muscle during an individual contraction increased significantly with contraction frequency (0.24 ± 0.03, 0.32 ± 0.02, and 0.36 ± 0.03 ml·N-1·min-1, respectively). This increased blood expulsion per contraction, coupled with the decreased time in the noncontractile phase as contraction frequency increased, resulted in the contractile phase contribution to mean venous blood flow becoming significantly greater (21 ± 4, 30 ± 4, and 38 ± 6%) as contraction frequency increased. These results demonstrate that the percent contribution of the muscle contractile phase to mean venous blood flow becomes significantly greater as contraction frequency (and thereby duty cycle and metabolic rate) increases and that this is in part due to increased blood expulsion per contraction.
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Zuo, Li, Leonardo Nogueira, and Michael C. Hogan. "Reactive oxygen species formation during tetanic contractions in single isolated Xenopus myofibers." Journal of Applied Physiology 111, no. 3 (September 2011): 898–904. http://dx.doi.org/10.1152/japplphysiol.00398.2011.

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Contracting skeletal muscle produces reactive oxygen species (ROS) that have been shown to affect muscle function and adaptation. However, real-time measurement of ROS in contracting myofibers has proven to be difficult. We used amphibian ( Xenopus laevis) muscle to test the hypothesis that ROS are formed during contractile activity in isolated single skeletal muscle fibers and that this contraction-induced ROS formation affects fatigue development. Single myofibers were loaded with 5 μM dihydrofluorescein-DA (Hfluor-DA), a fluorescent probe that reacts with ROS and results in the formation of fluorescein (Fluor) to precisely monitor ROS generation within single myofibers in real time using confocal miscroscopy. Three identical periods of maximal tetanic contractions (1 contraction/3 s for 2 min, separated by 60 min of rest) were conducted by each myofiber ( n = 6) at 20°C. Ebselen (an antioxidant) was present in the perfusate (10 μM) during the second contractile period. Force was reduced by ∼30% during each of the three contraction periods, with no significant difference in fatigue development among the three periods. The Fluor signal, indicative of ROS generation, increased significantly above baseline in both the first (42 ± 14%) and third periods (39 ± 10%), with no significant difference in the increase in fluorescence between the first and third periods. There was no increase of Fluor in the presence of ebselen during the second contractile period. These results demonstrated that, in isolated intact Xenopus myofibers, 1) ROS can be measured in real time during tetanic contractions, 2) contractile activity induced a significant increase above resting levels of ROS production, and 3) ebselen treatment reduced ROS generation to baseline levels but had no effect on myofiber contractility and fatigue development.
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Hamann, Jason J., Heidi A. Kluess, John B. Buckwalter, and Philip S. Clifford. "Blood flow response to muscle contractions is more closely related to metabolic rate than contractile work." Journal of Applied Physiology 98, no. 6 (June 2005): 2096–100. http://dx.doi.org/10.1152/japplphysiol.00400.2004.

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The magnitude of the blood flow response to exercise has been linked to both the contractile work performed and the metabolic cost of the activity. Under certain conditions, contractile work and metabolic cost may be dissociated. This study examined the blood flow response to trains of contractions when contraction duration was manipulated under conditions of similar tension-time indexes (isometric analog of work). Previous investigations have shown that trains of short-duration contractions have a greater ATP utilization, which may result from an augmented ion transport required for muscle activation and relaxation. On the basis of these findings, we hypothesized that the blood flow response would be greater to a train of short-duration contractions than a train of long-duration contractions. Canine gastrocnemius-plantaris muscle ( n = 8) was isolated, and blood flow assessed with an ultrasound flow probe placed around the popliteal artery. The sciatic nerve was stimulated to produce two contraction protocols that resulted in similar contraction-to-rest ratios: short duration: 0.25 s/0.75 s vs. long duration: 1 s /3 s. In accord with the design of the experiment, the tension-time indexes were identical for the two contraction protocols (short: 18.6 ± 1.0 vs. long: 18.6 ± 1.0 kN·s). Steady-state oxygen consumption was greater in the short-duration contractions (17.2 ± 0.9 ml·100 g−1·min−1) than in the long-duration contractions (11.7 ± 0.7 ml·100 g−1·min−1). Similarly, the steady-state blood flow was greater in contractions of short duration (125 ± 7 ml/min) compared with long-duration contractions (92 ± 7 ml/min). Contractions of short duration resulted in significantly higher oxygen consumptions and blood flows compared with contractions of long duration despite the same total contractile work. The blood flow response to muscle contraction appears to be more closely associated with muscle metabolism than contractile work performed.
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Meisner, Joshua K., Randolph H. Stewart, Glen A. Laine, and Christopher M. Quick. "Lymphatic vessels transition to state of summation above a critical contraction frequency." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 293, no. 1 (July 2007): R200—R208. http://dx.doi.org/10.1152/ajpregu.00468.2006.

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Although behavior of lymphatic vessels is analogous to that of ventricles, which completely relax between contractions, and blood vessels, which maintain a tonic constriction, the mixture of contractile properties can yield behavior unique to lymphatic vessels. In particular, because of their limited refractory period and slow rate of relaxation, lymphatic vessels lack the contractile properties that minimize summation in ventricles. We, therefore, hypothesized that lymphatic vessels transition to a state of summation when lymphatic vessel contraction frequency exceeds a critical value. We used an isovolumic, controlled-flow preparation to compare the time required for full relaxation with the time available to relax during diastole. We measured transmural pressure and diameter on segments of spontaneously contracting bovine mesenteric lymphatic vessels during 10 isovolumic volume steps. We found that beat-to-beat period (frequency−1) decreased with increases in diameter and that total contraction time was constant or slightly increased with diameter. We further found that the convergence of beat-to-beat period and contraction cycle duration predicted a critical transition value, beyond which the vessel does not have time to fully relax. This incomplete relaxation and resulting mechanical summation significantly increase active tension in diastole. Because this transition occurs within a physiological range, contraction summation may represent a fundamental feature of lymphatic vessel function.
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Kavvampalli Jyothirmayi Rani. "Some Applications via Coupled Fixed Point Theorems for (????, ????)-H-Contraction Mappings in Partial b- Metric Spaces." Communications on Applied Nonlinear Analysis 31, no. 5s (July 18, 2024): 351–71. http://dx.doi.org/10.52783/cana.v31.1055.

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This work establishes unique common coupled fixed point theorems for given mapping in complete partial b-metric spaces with the concept of (α, ϕ)-H-contraction in the context of partial b-metric spaces. (α, ϕ)-H-contraction Furthermore, we show how the results may be used and present applications to integral equations and Homotopy theory. Introduction In previous work, authors have discussed various fixed point theorems on partial b-metric spaces with (ψ, ϕ)-weakly contractive mappings, α−ψ-contractive type, Suzuki type contractions, rational contraction and H-weak contractions. In our work, with the help of (α, ϕ)-H-contraction, we investigated coupled fixed point theorems in partial b-metric spaces. Objectives: Finding the unique common fixed points for a given mapping in partial b-metric spaces via (α, ϕ)-H-contraction Methods with the help of α-admissible mapping, H-rational type, (α, ϕ)−H-contraction we have shown coupled fixed point findings in complete partial b-metric spaces Results: We obtained unique common coupled fixed point results via (α, ϕ)−H-contraction type for the given mapping in complete partial b-metric spaces. Conclusions: This present study uses contractive mappings of the H type in the reference of partial b-metric space to give some fixed point results, appropriate examples that illustrate the main findings, In addition, boundary value problems and homotopy applications are given.
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Siegle, M. L., and H. J. Ehrlein. "Interdigestive contractile patterns of the ileum in dogs." American Journal of Physiology-Gastrointestinal and Liver Physiology 253, no. 4 (October 1, 1987): G452—G460. http://dx.doi.org/10.1152/ajpgi.1987.253.4.g452.

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The aim of this study is to elucidate the nature of ileal interdigestive contractile patterns by the computerized analysis of the contraction spread and by videofluoroscopy. Conscious dogs equipped with closely spaced strain-gauge force transducers were used. Two patterns of repetitive, phasic contractions were recorded, migrating clusters and phase IIIs; both patterns consisted of repetitive, propagated contractions. Both patterns migrated aborad by sequential movement of contraction waves down the bowel. Consequently, the rate of migration of either of the entire patterns was slower than the propagation velocity of constituent, individual contraction waves. Both patterns differed in several parameters, especially the propagated contractions of the clusters spread over shorter distances (1.47 +/- 0.4 cm) than those of phase III (4.65 +/- 0.99 cm). Compared with these complex patterns, propagating power contractions represented single contractions that propagated aborad at the same velocity as the contraction waves of the complex patterns. All three patterns propelled luminal contents distally.
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Mehta, D., M. F. Wu, and S. J. Gunst. "Role of contractile protein activation in the length-dependent modulation of tracheal smooth muscle force." American Journal of Physiology-Cell Physiology 270, no. 1 (January 1, 1996): C243—C252. http://dx.doi.org/10.1152/ajpcell.1996.270.1.c243.

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The active isometric force developed by a muscle decreases at muscle lengths below an optimal length (Lo). However, when the length of an actively contracting muscle is abruptly decreased, a lower level of isometric force is reached during force redevelopment than when the contraction is initiated at the shorter length. This has been attributed to a deactivation of contractile proteins caused by shortening. In this study, intracellular Ca2+ and myosin light chain (MLC) phosphorylation were measured to assess the mechanisms for the modulation of isometric force caused by changing smooth muscle length before or during isometric contraction. The decline in isometric force between Lo and 0.5Lo was associated with decreases in MLC phosphorylation and intracellular Ca2+ during contractions elicited by acetylcholine or 60 mM KCl. Quick release of the muscle during contraction depressed force redevelopment at the shorter length but not MLC phosphorylation. We conclude that decreases in Ca(2+)-calmodulin-dependent MLC phosphorylation contribute significantly to the decline in isometric force at lengths below Lo, but the depression of contractility associated with the quick release of actively contracted smooth muscle is not caused by a shortening-induced deactivation of contractile proteins.
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Todd, Gabrielle, Janet L. Taylor, Jane E. Butler, Peter G. Martin, Robert B. Gorman, and Simon C. Gandevia. "Use of motor cortex stimulation to measure simultaneously the changes in dynamic muscle properties and voluntary activation in human muscles." Journal of Applied Physiology 102, no. 5 (May 2007): 1756–66. http://dx.doi.org/10.1152/japplphysiol.00962.2006.

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Force responses to transcranial magnetic stimulation of motor cortex (TMS) during exercise provide information about voluntary activation and contractile properties of the muscle. Here, TMS-generated twitches and muscle relaxation during the TMS-evoked silent period were measured in fresh, heated, and fatigued muscle. Subjects performed isometric contractions of elbow flexors in two studies. Torque and EMG were recorded from elbow flexor and extensor muscles. One study ( n = 6) measured muscle contraction times and relaxation rates during brief maximal and submaximal contractions in fresh and fatigued muscle. Another study ( n = 7) aimed to 1) assess the reproducibility of muscle contractile properties during brief voluntary contractions in fresh muscle, 2) validate the technique for contractile properties in passively heated muscle, and 3) apply the technique to study contractile properties during sustained maximal voluntary contractions. In both studies, muscle contractile properties during voluntary contractions were compared with the resting twitch evoked by motor nerve stimulation. Measurement of muscle contractile properties during voluntary contractions is reproducible in fresh muscle and reveals faster and slower muscle relaxation rates in heated and fatigued muscle, respectively. The technique is more sensitive to altered muscle state than the traditional motor nerve resting twitch. Use of TMS during sustained maximal contractions reveals slowing of muscle contraction and relaxation with different time courses and a decline in voluntary activation. Voluntary output from the motor cortex becomes insufficient to maintain complete activation of muscle, although slowing of muscle contraction and relaxation indicates that lower motor unit firing rates are required for fusion of force.
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Dissertations / Theses on the topic "Contraction"

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Murtada, Sae-Il. "Smooth muscle modeling activation and contraction of contractile units in smooth muscle /." Licentiate thesis, Stockholm : Skolan för teknikvetenskap, Kungliga Tekniska högskolan, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11349.

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Sringeri, Vageeswara Abhijit. "Tensor Contraction Optimizations." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1440399261.

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Njoya, Nadine Katia. "Contraction-Expansion Protocols." Digital Commons @ East Tennessee State University, 2008. https://dc.etsu.edu/etd/1971.

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An approach to a new class of compounds known as bridgehead dienone is described. The route is based on a tandem contraction-expansion event in which the contraction triggers the expansion. The two steps involved are a palladium-catalyzed Favorskii contraction and a cis-divinyl cyclopropanone rearrangement. Progress towards these goals is reported.
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Wang, Wei 1972 Oct 17. "Contraction and partial contraction : a study of synchronization in nonlinear networks." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/30343.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2005.
Includes bibliographical references (p. 121-128).
This thesis focuses on the study of collective dynamic behaviors, especially the spontaneous synchronization behavior, of nonlinear networked systems. We derives a body of new results, based on contraction and partial contraction analysis. Contraction is a property regarding the convergence between two arbitrary system trajectories. A nonlinear dynamic system is called contracting if initial conditions or temporary disturbances are forgotten exponentially fast. Partial contraction, introduced in this thesis, is a straightforward but more general application of contraction. It extends contraction analysis to include convergence to behaviors or to specific properties (such as equality of state components, or convergence to a manifold). Contraction and partial contraction provide powerful analysis tools to investigate the stability of large-scale complex systems. For diffusively coupled nonlinear systems, for instance, a general synchronization condition can be derived which connects synchronization rate to net- work structure explicitly. The results are applied to construct flocking or schooling models by extending to coupled networks with switching topology. We further study the networked systems with different kinds of group leaders, one specifying global orientation (power leader), another holding target dynamics (knowledge leader). In a knowledge-based leader-followers network, the followers obtain dynamics information from the leader through adaptive learning. We also study distributed networks with non-negligible time-delays by using simplified wave variables and other contraction-oriented analysis. Conditions for contraction to be preserved regardless of the explicit values of the time-delays are derived.
(cont.) Synchronization behavior is shown to be robust if the protocol is linear. Finally, we study the construction of spike-based neural network models, and the development of simple mechanisms for fast inhibition and de-synchronization.
by Wei Wang.
Ph.D.
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Corin, Karolina A. (Karolina Ann) 1981. "Inhibition of myofibroblast contraction." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/32381.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2005.
Includes bibliographical references (p. 46-49).
Although current medical procedures cannot restore complete function of a transected nerve, inserting both of its ends in a tube helps it regenerate. The regenerate is inferior to the uninjured nerve: it has a smaller diameter and poorer electrical conduction. Layers of contractile cells known as myofibroblasts have been observed around regenerated nerve portions. An inverse relationship between the layer thickness and the quality of the regenerate has also been observed. These findings suggest that the cells are exerting contractile forces which prevent the regenerating nerve from fully developing. Inhibiting this contraction should thus improve the quality of nerve regeneration. Alpha smooth muscle actin ([alpha]-SMA) is a critical contractile protein. Its expression can be upregulated by the growth factor TGF-[beta]1, and blocked by the pharmacological agent PP2. To investigate whether blocking SMA expression alone can inhibit myofibroblast contraction, NR6 wild type fibroblasts were seeded into short cylindrical collagen-GAG matrices, and administered either media alone, media with TGF-[beta]1 (3ng/ml), or media with TGF-[beta]1 and PP2 (10 [mu]M). Non-seeded matrix samples were also prepared. The matrix diameters were measured every day for 12 days, after which the matrices were digested and the number of adhered cells were counted. The daily change in matrix diameter was calculated. The results showed that the cells contracted the matrices. TGF-[beta]1 increased cell contractility, while PP2 inhibited it..
(cont.) Normalizing the Day 12 diameter change measurements to cell number and the original matrix diameter showed that TGF-[beta] increased the strain generated by each cell ... relative to ... for untreated cells), and that PP2 counteracted this effect (...). Using the linear elastic constitutive relations, the average force exerted per cell was calculated for the untreated cells (...), TGF-[beta]1 stimulated cells (...), and TGF-[beta] + PP2 stimulated cells (...). The cell counts after Day 12 indicate that PP2 interferes with cell adhesion to the matrices. After 6 hours in culture, 21% of untreated cells, 25% percent of cells treated with TGF-[beta] 1, and 25% of cells treated with TGF-[beta]1 and PP2 had adhered. By Day 12, only 12% of the seeded untreated cells, 14% of cells treated with TGF-[beta] I, and 3.2% of cells treated with both TGF-[beta]1 and PP2 remained adhered. This study thus indicates that PP2 inhibits cellular contraction, possibly by preventing cell-substrate adhesion
by Karolina A. Corin.
S.M.
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Reis, Maurício Duarte Luís. "On theory multiple contraction." Doctoral thesis, Universidade da Madeira, 2011. http://hdl.handle.net/10400.13/255.

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The one which is considered the standard model of theory change was presented in [AGM85] and is known as the AGM model. In particular, that paper introduced the class of partial meet contractions. In subsequent works several alternative constructive models for that same class of functions were presented, e.g.: safe/kernel contractions ([AM85, Han94]), system of spheres-based contractions ([Gro88]) and epistemic entrenchment-based contractions ([G ar88, GM88]). Besides, several generalizations of such model were investigated. In that regard we emphasise the presentation of models which accounted for contractions by sets of sentences rather than only by a single sentence, i.e. multiple contractions. However, until now, only two of the above mentioned models have been generalized in the sense of addressing the case of contractions by sets of sentences: The partial meet multiple contractions were presented in [Han89, FH94], while the kernel multiple contractions were introduced in [FSS03]. In this thesis we propose two new constructive models of multiple contraction functions, namely the system of spheres-based and the epistemic entrenchment-based multiple contractions which generalize the models of system of spheres-based and of epistemic entrenchment-based contractions, respectively, to the case of contractions (of theories) by sets of sentences. Furthermore, analogously to what is the case in what concerns the corresponding classes of contraction functions by one single sentence, those two classes are identical and constitute a subclass of the class of partial meet multiple contractions. Additionally, and as the rst step of the procedure that is here followed to obtain an adequate de nition for the system of spheres-based multiple contractions, we present a possible worlds semantics for the partial meet multiple contractions analogous to the one proposed in [Gro88] for the partial meet contractions (by one single sentence). Finally, we present yet an axiomatic characterization for the new class(es) of multiple contraction functions that are here introduced.
Eduardo Fermé
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Makur, Anuran. "Information contraction and decomposition." Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/122692.

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This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Thesis: Sc. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2019
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 327-350).
Information contraction is one of the most fundamental concepts in information theory as evidenced by the numerous classical converse theorems that utilize it. In this dissertation, we study several problems aimed at better understanding this notion, broadly construed, within the intertwined realms of information theory, statistics, and discrete probability theory. In information theory, the contraction of f-divergences, such as Kullback-Leibler (KL) divergence, X²-divergence, and total variation (TV) distance, through channels (or the contraction of mutual f-information along Markov chains) is quantitatively captured by the well-known data processing inequalities.
These inequalities can be tightened to produce "strong" data processing inequalities (SDPIs), which are obtained by introducing appropriate channel-dependent or source-channel-dependent "contraction coefficients." We first prove various properties of contraction coefficients of source-channel pairs, and derive linear bounds on specific classes of such contraction coefficients in terms of the contraction coefficient for X²-divergence (or the Hirschfeld-Gebelein-Rényi maximal correlation). Then, we extend the notion of an SDPI for KL divergence by analyzing when a q-ary symmetric channel dominates a given channel in the "less noisy" sense. Specifically, we develop sufficient conditions for less noisy domination using ideas of degradation and majorization, and strengthen these conditions for additive noise channels over finite Abelian groups.
Furthermore, we also establish equivalent characterizations of the less noisy preorder over channels using non-linear operator convex f-divergences, and illustrate the relationship between less noisy domination and important functional inequalities such as logarithmic Sobolev inequalities. Next, adopting a more statistical and machine learning perspective, we elucidate the elegant geometry of SDPIs for X²-divergence by developing modal decompositions of bivariate distributions based on singular value decompositions of conditional expectation operators. In particular, we demonstrate that maximal correlation functions meaningfully decompose the information contained in categorical bivariate data in a local information geometric sense and serve as suitable embeddings of this data into Euclidean spaces.
Moreover, we propose an extension of the well-known alternating conditional expectations algorithm to estimate maximal correlation functions from training data for the purposes of feature extraction and dimensionality reduction. We then analyze the sample complexity of this algorithm using basic matrix perturbation theory and standard concentration of measure inequalities. On a related but tangential front, we also define and study the information capacity of permutation channels. Finally, we consider the discrete probability problem of broadcasting on bounded indegree directed acyclic graphs (DAGs), which corresponds to examining the contraction of TV distance in Bayesian networks whose vertices combine their noisy input signals using Boolean processing functions.
This generalizes the classical problem of broadcasting on trees and Ising models, and is closely related to results on reliable computation using noisy circuits, probabilistic cellular automata, and information flow in biological networks. Specifically, we establish phase transition phenomena for random DAGs which imply (via the probabilistic method) the existence of DAGs with logarithmic layer size where broadcasting is possible. We also construct deterministic DAGs where broadcasting is possible using expander graphs in deterministic quasi-polynomial or randomized polylogarithmic time in the depth. Lastly, we show that broadcasting is impossible for certain two-dimensional regular grids using techniques from percolation theory and coding theory.
by Anuran Makur.
Sc. D.
Sc.D. Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science
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Corona, Benjamin T. "Junctophilin Damage Contributes to Early Force Deficits and Excitation-Contraction Coupling Failure after Performing Eccentric Contractions." Digital Archive @ GSU, 2009. http://digitalarchive.gsu.edu/kin_health_diss/4.

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Junctophilins (JP1 & JP2) are expressed in skeletal muscle and are the primary proteins involved in transverse (T)-tubule and sarcoplasmic reticulum (SR) membrane apposition. During the performance of eccentric contractions, the apposition of T-tubule and SR membranes may be disrupted, resulting in excitation-contraction (EC) coupling failure and thus reduced force-producing capacity. In this study, we made three primary observations: 1) Through the first three days after the performance of 50 eccentric contractions in vivo by the left hindlimb anterior crural muscles of female mice, both JP1 and JP2 were significantly reduced by ~50 and 35%, respectively, while no reductions were observed after the performance of non-fatiguing concentric contractions; 2) following the performance of a repeated bout 50 eccentric contractions in vivo, only JP1 was immediately reduced (~30%) but recovered by 3d post-injury in tandem with the recovery of strength and EC coupling; and 3) following the performance of 10 eccentric contractions at either 15 or 35˚C by isolated mouse EDL muscle, isometric force, EC coupling, and JP1 and JP2 were only reduced after the 35˚C eccentric contractions. Regression analysis of JP1 and JP2 content in TA and EDL muscles from each set of experiments indicated that JP damage is significantly associated with early (0 – 3d) strength deficits after performing eccentric contractions (R = 0.49; P < 0.001). As a whole, the results of this study indicate that JP damage plays in role in early force deficits due to EC coupling failure following the performance of eccentric contractions.
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Lohmiller, Winfried Stefan 1971. "Contraction analysis of nonlinear systems." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/9793.

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Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1999.
Includes bibliographical references (leaves 87-90).
This thesis derives new results in nonlinear system analysis using methods inspired from fluid mechanics and differential geometry. Based on a differential analysis of convergence, these results may be viewed as generalizing the classical Krasovskii the­orem, as well as linear eigenvalue analysis. A central feature is that convergence and limit behavior are in a sense treated separately, leading to significant conceptual simplifications. We establish new combination properties of nonlinear dynamic systems and use them to derive simple controller and observer designs for mechanical systems such as aircraft, underwater vehicles, and robots. The method is also applied to chemical chain reactions and mixture processes. The relative simplicity of these designs stems from their effective exploitation of the systems' structural specificities. Next, we analyze and quantify the global stability properties of physical partial differential equations such as the heat equation, or the Schroedinger equation. Lyapunov exponents are not coordinate-invariant, and thus their exact physical meaning is somewhat questionable. As an alternative, we suggest an extension of linear eigenvalue analysis to nonlinear dynamic systems. Finally, the thesis derives new controller and observer designs for general nonlinear dynamic systems. In particular, an extension of feedback linearization is proposed when the corresponding integrability conditions are violated.
by Winfried Stefan Lohmiller.
Ph.D.
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Novel, Maxence. "Contraction de cônes complexes multidimensionnels." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS263/document.

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L'objet de cette thèse est l'introduction, l'étude et l'utilisation des cônes complexes multidimensionnels. Dans un premier temps, nous étudions la grassmannienne des espaces de Banach. Nous définissons une notion de bonne décomposition pour les espaces de dimension p et nous démontronsl'équivalence entre la distance de Hausdorff sur la grassmannienne et la distance fournie par une norme sur l'algèbre extérieure.Dans un deuxième temps, nous définissons les cônes complexes p-dimensionnels ainsi qu'une jauge sur les sous-espaces de dimension p de ces cônes. Nous montrons alors un principe de contraction pour cette jauge. Cela nous permet de prouver, pour un opérateur contractant un tel cône, l'existence d'un trou spectral séparant les p valeurs propres dominantes du reste du spectre. Nous utilisons cette théorie pourdémontrer un théorème de régularité analytique pour les exposants de Lyapunov d'un produit aléatoire d'opérateurs contractant un même cône.Nous donnons également une comparaison entre la distance de Hausdorff entre espaces vectoriels et notre jauge.Enfin, nous introduisons une notion de cône dual pour les cônes p-dimensionnels. Dans ce cadre, nous prouvons que les propriétéstopologiques d'un cône se traduisent en propriétés topologiques sur son dual, et réciproquement. Nous complétons le théorème de régularitéprécédent en démontrant l'existence et la régularité d'une décomposition de l'espace en "espace lent" et "espace rapide"
The subject of this thesis is the introduction, the study and the applications of multidimensional complex cones. First, we study the grassmannian of Banach space. We define a notion of right decomposition for p-dimensional spaces and we prove the equivalence between theHausdorff distance on the grassmannian and the distance given by a norm on the exterior algebra.Then, we define p-dimensional complex cones and a gauge on the subspaces of dimension p of these cones. We show a contraction principle for thisgauge. This allows us to prove, for an operator contracting such a cone, the existence of a spectral gap which isolate the p leading eigenvaluesfrom the rest of the spectrum. We use this theory to prove a theorem of analytic regularity for Lyapunov exponents of a random product ofoperators contracting a cone. We also give a comparison between the Hausdorff distance for vector spaces and our gauge.Finally, we introduce a notion of dual cone for p-dimensional cones. In this setting, we prove that the topological properties of a cone translateinto topological properties for its dual and conversely. We complete the previous regularity theorem by proving the existence and the regularity ofa dominated splitting of the space into a "fast space" and a "slow space"
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Books on the topic "Contraction"

1

Kelly. Contraction. Summerland, BC, Canada: The author, 2003.

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Bers, Donald M. Excitation-Contraction Coupling and Cardiac Contractile Force. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-017-1512-6.

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Bers, Donald M. Excitation-Contraction Coupling and Cardiac Contractile Force. Dordrecht: Springer Netherlands, 2001. http://dx.doi.org/10.1007/978-94-010-0658-3.

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Bagshaw, Clive R. Muscle Contraction. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-015-6839-5.

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1938-, Simmons Robert M., and Physiological Society (Great Britain), eds. Muscular contraction. Cambridge: Cambridge University Press, 1992.

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Needham, Duncan, and Anthony Hotson, eds. Expansionary Fiscal Contraction. Cambridge: Cambridge University Press, 2014. http://dx.doi.org/10.1017/cbo9781107337626.

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Friedman, Milton. The great contraction. Princeton: Princeton University Press, 2009.

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Rüegg, Johann Caspar. Calcium in Muscle Contraction. Berlin, Heidelberg: Springer Berlin Heidelberg, 1992. http://dx.doi.org/10.1007/978-3-642-77560-4.

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Rall, Jack A. Mechanism of Muscular Contraction. New York, NY: Springer New York, 2014. http://dx.doi.org/10.1007/978-1-4939-2007-5.

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Unit, Leicestershire Health Authority Mental Health Services. Expansion and contraction plan. [Leicester]: [Leicestershire Health Authority, 1990.

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Book chapters on the topic "Contraction"

1

Gooch, Jan W. "Contraction." In Encyclopedic Dictionary of Polymers, 169. New York, NY: Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4419-6247-8_2877.

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Taber, Larry A. "Contraction." In Continuum Modeling in Mechanobiology, 209–52. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-43209-6_5.

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Hansson, Sven Ove. "Contraction." In Descriptor Revision, 151–62. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-53061-1_10.

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Bers, Donald M. "Excitation-Contraction Coupling." In Excitation-Contraction Coupling and Cardiac Contractile Force, 203–44. Dordrecht: Springer Netherlands, 2001. http://dx.doi.org/10.1007/978-94-010-0658-3_8.

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Bers, Donald M. "Excitation-Contraction Coupling." In Excitation-Contraction Coupling and Cardiac Contractile Force, 119–48. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-017-1512-6_7.

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Hansson, Sven Ove. "Theory Contraction and Base Contraction Unified." In Readings in Formal Epistemology, 219–45. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-20451-2_14.

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Smith, C. A., and E. J. Wood. "Muscle contraction." In Cell Biology, 391–422. Boston, MA: Springer US, 1996. http://dx.doi.org/10.1007/978-1-4613-0441-8_13.

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Gooch, Jan W. "Contraction Allowance." In Encyclopedic Dictionary of Polymers, 169. New York, NY: Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4419-6247-8_2878.

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Holmes, K. C. "Muscle Contraction." In Novartis Foundation Symposium 213 - The Limits of Reductionism in Biology, 76–92. Chichester, UK: John Wiley & Sons, Ltd., 2007. http://dx.doi.org/10.1002/9780470515488.ch6.

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Cygan, Marek. "Randomized Contraction." In Encyclopedia of Algorithms, 1738–41. New York, NY: Springer New York, 2016. http://dx.doi.org/10.1007/978-1-4939-2864-4_764.

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Conference papers on the topic "Contraction"

1

Chaves, Juliana N., Hani C. Yehia, and Henrique R. Martins. "Development of a portable labor-contraction monitor based on mechanomyography." In Simpósio Brasileiro de Computação Aplicada à Saúde. Sociedade Brasileira de Computação (SBC), 2022. http://dx.doi.org/10.5753/sbcas_estendido.2022.222422.

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Mechanomyography is a technique that measures the mechanical signal observed from the muscle surface during the contraction. It is expected to be a promising tool to evaluate uterine dynamics even though the uterus contraction is known to be involuntary. This study aimed to describe the development of a portable device based on mechanomyography to monitor uterine contraction. To assess the system was performed isometric contractions of the rectus femoris muscle with varying loads. The acquired data showed that the system could identify each contraction's onset, offset, and amplitude. The sensors and the system architecture proved to be a promising tool for the desired application.
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Eschen, Kevin, and Julianna Abel. "Effect of Geometric Design Parameters on Contractile SMA Knitted Actuator Performance." In ASME 2017 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/smasis2017-3926.

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Shape memory alloy (SMA) knitted actuators are a type of functional fabric that uses shape memory alloy wire as an active fiber within a knitted textile. Through intentional design of the SMA knitted actuator geometry, various two- and three-dimensional actuation motions, such as scrolling and contraction [1], can be accomplished. Contractile SMA knitted actuators leverage the unique thermo-mechanical properties of SMA wires by integrating them within the hierarchical knitted structure to achieve large distributed uniaxial contractions and variable stiffness behavior upon thermal actuation. During the knit manufacturing process, the SMA wire is bent into a network of interlacing adjacent loops, storing potential energy within the contractile SMA knitted actuator. Thermal actuation above the wire-specific austenite finish temperature leads to a partial recovery of the bending deformations, resulting in large distributed uniaxial contraction (15–40% actuation contraction observed) of the SMA knitted actuator. The achievable load capacity and %-actuation contraction are dependent on the geometric loop parameters of the contractile SMA knitted actuator. While exact descriptions of the geometric loop parameters exist, a reduction of the geometric complexity is advantageous for high-level contractile SMA knitted actuator design procedures. This paper defines a simple geometric measure, the non-dimensional knit density, and experimentally correlates the contractile SMA knitted actuator performance to this measure. The experimentally demonstrated dependency of relevant actuator metrics on the knit density and the wire diameter, suggests the usability of the simplified geometry definition for a high-level contractile SMA knitted actuator design.
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Haldimann, Jonas Philipp, Gabriele Kern-Isberner, and Christoph Beierle. "Syntax Splitting for Iterated Contractions." In 17th International Conference on Principles of Knowledge Representation and Reasoning {KR-2020}. California: International Joint Conferences on Artificial Intelligence Organization, 2020. http://dx.doi.org/10.24963/kr.2020/47.

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Parikh developed the notion of syntax splitting to describe belief sets with independent parts. He also formulated a postulate demanding that belief revisions respect syntax splittings in belief sets. The concept of syntax splitting was later transferred to epistemic states with total preorders and ranking functions by Kern-Isberner and Brewka along with corresponding postulates for belief revisions. Besides revision, contraction is also a central operation in the field of general belief change. In this paper, we analyse belief contractions with respect to syntax splitting. Based on the work on syntax splitting for revision, we develop syntax splitting postulates for contractions on ranking functions, on epistemic states with total preorder, and on belief sets. Finally, we evaluate different contractions from the literature, namely moderate contraction, natural contraction, lexicographic contraction, and c-contractions with respect to the newly developed contraction postulates.
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Garapa, Marco, Eduardo Fermé, and Maurício D. L. Reis. "Shielded Base Contraction (Extended Abstract)." In Twenty-Eighth International Joint Conference on Artificial Intelligence {IJCAI-19}. California: International Joint Conferences on Artificial Intelligence Organization, 2019. http://dx.doi.org/10.24963/ijcai.2019/889.

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In this paper we study a kind of non-prioritized contraction operator on belief bases -known as shielded base contractions. We propose twenty different classes of shielded base contractions and obtain axiomatic characterizations for each one of them. Additionally we thoroughly investigate the interrelations (in the sense of inclusion) among all those classes.
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Mercado, Alejandro J., Daniel Grimaldi, and Ricardo O. Rodriguez. "Weak-Ensconcement for Shielded Base Contraction." In 20th International Conference on Principles of Knowledge Representation and Reasoning {KR-2023}. California: International Joint Conferences on Artificial Intelligence Organization, 2023. http://dx.doi.org/10.24963/kr.2023/51.

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In this article, we provide the weak version of ensconcement which characterizes an interesting family of Shielded base contractions. In turn, this characterization induces a class of AGM contractions satisfying certain postulates that we reveal here. Finally, we show a connection among the class of contractions given by our weak ensconcement and other kinds of base contraction operators. In doing so, we also point out a flaw in the original theorems that link the epistemic entrenchment with ensconcement (which are well established in the literature), and then we provide two possible solutions.
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Van Diest, M. J., T. J. Verbeuren, and A. G. Herman. "RELAXATIONS INDUCED BY LIPOXYGENASE METABOLITES OF ARACHI-DONIC ACID IN SPLENIC ARTERIES OF THE DOG." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643796.

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The lipoxygenase metabolites of arachidonic acid, 15 hydroperoxyeicosatetraenoic acid (15HPETE) and its hydroxy derivative (15HETE) evoke contractions in a variety of isolated blood vessels. We recently were able to show that thromboxane A2 (TXA2)-receptor antagonists BM13177 and BM13505 suppress the contractions induced by lipoxygenase metabolites in canine splenic arteries, and that these compounds also inhibit the contractile effects of PGF2α and of the TXA2-mimetic U46619. We also reported that 15HETE and 15HPETE cause relaxations of isolated dog arteries when the tissues are contracted with prostaglandin F2α (PGF2α) or with U46619 and suggested that lipoxygenase metabolites may act as endogenous antagonists towards prostaglandin receptors. The present study was designed to investigate the effects of lipoxygenase metabolites of arachidonic acid in isolated splenic arteries in which the tone is raised by various agonists.Segments of canine splenic arteries with or without endothelium were placed in organ chambers filled with Krebs-Ringer solution at 37°C for isometric tension recording. Responses to 15HPETE were obtained in segments which were contracted with serotonin, K+, PGF2α or noradrenaline (the latter with or without BM13505); concentrations causing comparable levels of contraction were selected. HPETE evoked relaxations in segments with and without endothelium, during the contractions evoked by K+, PGF2α and noradrenaline (with or without BM13505). At higher concentrations, 15HPETE caused relaxations only during contractions induced by PGF2α and noradrenaline with BM13505. Our results suggest that 15HPETE can cause relaxations by two different mechanisms :(1) 15HPETE may act as an antagonist to PGF2α, which causes its contraction via the TXA2-receptor and,(2) in presence of BM13505, it suppresses the contractions to noradrenaline via an endothelium independent mechanism.
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Ribeiro, Jandson S. "Kernel Contraction and the Order of Relevance." In 19th International Conference on Principles of Knowledge Representation and Reasoning {KR-2022}. California: International Joint Conferences on Artificial Intelligence Organization, 2022. http://dx.doi.org/10.24963/kr.2022/30.

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The postulate of relevance provides a suitable and general notion of minimal change for belief contraction. Relevance is tightly connected to smooth kernel contractions when an agent's epistemic state is represented as a logically closed set of formulae. This connection, however, breaks down when an agent's epistemic state is represented as a set of formulae not necessarily logically closed. We investigate the cause behind this schism, and we reconnect relevance with smooth kernel contractions by constraining the behaviour of their choice mechanisms and epistemic preference relations. Our first representation theorem connects smooth kernel contractions with a novel class of epistemic preference relations. For our second representation theorem, we introduce the principle of symmetry of removal that relates relevance to epistemic choices. For the last theorem, we devise a novel class of smooth kernel contractions, that satisfy relevance, which are based on epistemic preference relations that capture the principle of symmetry of removal.
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Philips, C. A. "Parallel graph contraction." In the first annual ACM symposium. New York, New York, USA: ACM Press, 1989. http://dx.doi.org/10.1145/72935.72952.

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Costa, Horacio Arló, and Hailin Liu. "Value-based contraction." In hte 13th Conference. New York, New York, USA: ACM Press, 2011. http://dx.doi.org/10.1145/2000378.2000385.

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Deshpande, A., K. Ramisetty, F. W. Chambers, M. E. McNally, and R. M. Hoffman. "Effect of a Symmetric Contraction on the Concentration Profiles of a Particle-Laden Slurry." In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-62809.

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In-line measurements and sample stream withdrawals for on-line and/or at-line measurements of slurries flowing in horizontal pipes can be complicated by nonuniform slurry profiles. More uniform profiles would improve measurements. Area contractions are a common means used to produce more uniform velocity fields for single phase flows. For example, contractions are used to condition the flow entering wind tunnel test sections and make velocity profiles more uniform at venturi throats. It was desired to determine whether area contractions could be used to make slurry concentration profiles more uniform in horizontal pipe flows. An ASME flow nozzle with a contraction diameter ratio of 0.5 was chosen as a well defined geometry to consider in a Computational Fluid Dynamic (CFD) study of the effects of a contraction on slurry concentration profiles. The pipe was 2.8 m long with a 50.8 mm diameter. The entrance of the contraction was placed at 35 pipe diameters from the inlet in fully developed flow. A length of 20 diameters followed the contraction. The slurry had a xylene liquid phase and an ADP solid phase with a density ratio of 1.7. The simulations were performed at primary phase velocities of 2 m/s and 4 m/s, corresponding to Reynolds numbers of 1.4E05 and 2.8E05. Spherical particle diameters of 38, 75, and 150 μm were used at concentrations of 0.05, 0.2, and 0.3. ANSYS FLUENT 12 software was used with the standard k-ε turbulence model and standard wall function. The mixture multi-phase model was used for the two-phase flow. An unstructured tetrahedral meshing scheme was used with 1.4 million elements. The grid was adjusted until the condition 30 < y+ <60 for the mesh point nearest the wall was satisfied. A grid refinement study was performed to insure grid independence. The computational scheme first was validated by comparing pipe flow velocity and concentration profiles to results in the literature. The computations performed with the contraction showed that in all cases the concentration profiles of the solid particles displayed greater uniformity than the profiles in the pipe upstream of the contraction. The effect of the contraction was more pronounced for the larger particles. As in the case of single phase flows, the contraction caused the axial turbulence intensity to decrease. The greater uniformity of the concentration profiles at the exit plane of the nozzle, suggest that the contraction can provide better conditions for performing measurements of a particle-laden slurry.
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Reports on the topic "Contraction"

1

Phillips, Cynthia A. Parallel Graph Contraction. Fort Belvoir, VA: Defense Technical Information Center, May 1989. http://dx.doi.org/10.21236/ada211916.

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Westerlind, Kim. Muscle Contraction Arrests Tumor Growth. Fort Belvoir, VA: Defense Technical Information Center, September 2006. http://dx.doi.org/10.21236/ada572645.

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Kedem, Benjamin, and Sidney Yakowitz. On the Contraction Mapping Method for Frequency Detection. Fort Belvoir, VA: Defense Technical Information Center, June 1991. http://dx.doi.org/10.21236/ada454953.

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Bordo, Michael, Ehsan Choudhri, and Anna Schwartz. Could Stable Money Have Averted The Great Contraction? Cambridge, MA: National Bureau of Economic Research, October 1993. http://dx.doi.org/10.3386/w4481.

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Kim, Sei-Wan, Donghyun Park, and Shu Tian. How Does Inflation in Advanced Economies Affect Emerging Market Bond Yields? Empirical Evidence from Two Channels. Asian Development Bank, September 2023. http://dx.doi.org/10.22617/wps230372-2.

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This study uses multivariable smooth transition autoregressive–vector autoregressive (STAR–VAR), a novel model to explore how inflation in advanced economies affects emerging market bond yields. Results reveal two key findings. First, advanced economy inflation has a significant effect on emerging market bond yields. Second, the short-run effect of advanced economy inflation on the bond yields of emerging markets is asymmetric between the expansion and contraction regimes. The effect is mostly positive in both regimes but stronger in a bond yield’s contraction regime.
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Li, Ta-Hsin, Benjamin Kedem, and Sid Yakowitz. Asymptotic Normality of the Contraction Mapping Estimator for Frequency Estimation. Fort Belvoir, VA: Defense Technical Information Center, September 1991. http://dx.doi.org/10.21236/ada453892.

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Li, Ta-hsin, and Benjamin Kedem. Strong Consistency of the Contraction Mapping Method for Frequency Estimation. Fort Belvoir, VA: Defense Technical Information Center, June 1991. http://dx.doi.org/10.21236/ada454944.

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Solomonik, Edgar, Devin Matthews, Jeff R. Hammond, John F. Stanton, and James Demmel. A Massively Parallel Tensor Contraction Framework for Coupled-Cluster Computations. Fort Belvoir, VA: Defense Technical Information Center, August 2014. http://dx.doi.org/10.21236/ada614387.

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Rockoff, Hugh. Deflation, Silent Runs, and Bank Holidays, in the Great Contraction. Cambridge, MA: National Bureau of Economic Research, March 2003. http://dx.doi.org/10.3386/w9522.

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Levy Yeyati, Eduardo, and Ugo Panizza. The Elusive Costs of Sovereign Defaults. Inter-American Development Bank, November 2006. http://dx.doi.org/10.18235/0010862.

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Few would dispute that sovereign defaults entail significant economic costs, including, most notably, important output losses. However, most of the evidence supporting this conventional wisdom, based on annual observations, suffers from serious measurement and identification problems. To address these drawbacks, we examine the impact of default on growth by looking at quarterly data for emerging economies. We find that, contrary to what is typically assumed, output contractions precede defaults. Moreover, we find that the trough of the contraction coincides with the quarter of default, and that output starts to grow thereafter, indicating that default episode seems to mark the beginning of the economic recovery rather than a further decline. This suggests that, whatever negative effects a default may have on output, those effects result from anticipation of a default rather than the default itself.
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