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1

Bogle, Jamie M., David A. Zapala, Robin Criter, and Robert Burkard. "The Effect of Muscle Contraction Level on the Cervical Vestibular Evoked Myogenic Potential (cVEMP): Usefulness of Amplitude Normalization." Journal of the American Academy of Audiology 24, no. 02 (2013): 077–88. http://dx.doi.org/10.3766/jaaa.24.2.2.

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Background: The cervical vestibular evoked myogenic potential (cVEMP) is a reflexive change in sternocleidomastoid (SCM) muscle contraction activity thought to be mediated by a saccular vestibulo-collic reflex. CVEMP amplitude varies with the state of the afferent (vestibular) limb of the vestibulo-collic reflex pathway, as well as with the level of SCM muscle contraction. It follows that in order for cVEMP amplitude to reflect the status of the afferent portion of the reflex pathway, muscle contraction level must be controlled. Historically, this has been accomplished by volitionally controll
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2

ZLATANOV, BOYAN. "Error estimates for approximating best proximity points for cyclic contractive maps." Carpathian Journal of Mathematics 32, no. 2 (2016): 265–70. http://dx.doi.org/10.37193/cjm.2016.02.15.

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We find a priori and a posteriori error estimates of the best proximity point for the Picard iteration associated to a cyclic contraction map, which is defined on a uniformly convex Banach space with modulus of convexity of power type.
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3

Beirão da Veiga, L., C. Canuto, R. H. Nochetto, G. Vacca, and M. Verani. "Adaptive VEM: Stabilization-Free A Posteriori Error Analysis and Contraction Property." SIAM Journal on Numerical Analysis 61, no. 2 (2023): 457–94. http://dx.doi.org/10.1137/21m1458740.

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4

Canuto, Claudio, and Davide Fassino. "Higher-order adaptive virtual element methods with contraction properties." Mathematics in Engineering 5, no. 6 (2023): 1–33. http://dx.doi.org/10.3934/mine.2023101.

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<abstract><p>The realization of a standard Adaptive Finite Element Method (AFEM) preserves the mesh conformity by performing a completion step in the refinement loop: In addition to elements marked for refinement due to their contribution to the global error estimator, other elements are refined. In the new perspective opened by the introduction of Virtual Element Methods (VEM), elements with hanging nodes can be viewed as polygons with aligned edges, carrying virtual functions together with standard polynomial functions. The potential advantage is that all activated degrees of fre
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5

Bokhove, O., A. Kalogirou, and W. Zweers. "From Bore–Soliton–Splash to a New Wave-to-Wire Wave-Energy Model." Water Waves 1, no. 2 (2019): 217–58. http://dx.doi.org/10.1007/s42286-019-00022-9.

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AbstractWe explore extreme nonlinear water-wave amplification in a contraction or, analogously, wave amplification in crossing seas. The latter case can lead to extreme or rogue-wave formation at sea. First, amplification of a solitary-water-wave compound running into a contraction is disseminated experimentally in a wave tank. Maximum amplification in our bore–soliton–splash observed is circa tenfold. Subsequently, we summarise some nonlinear and numerical modelling approaches, validated for amplifying, contracting waves. These amplification phenomena observed have led us to develop a novel w
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6

Waldrop, T. G., and R. W. Stremel. "Muscular contraction stimulates posterior hypothalamic neurons." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 256, no. 2 (1989): R348—R356. http://dx.doi.org/10.1152/ajpregu.1989.256.2.r348.

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Recent studies have suggested that the subthalamic locomotor region (STLR) of the posterior hypothalamus is involved in modulating cardiorespiratory responses to feedback from contracting muscles. The purpose of this study was to determine whether neurons in this hypothalamic region alter their discharge frequency during contraction of hindlimb muscles. Stainless steel electrodes were used to record single-unit activity of STLR neurons during static and rhythmic contractions of hindlimb muscles in anesthetized cats. Recordings were also made from neurons in areas outside but surrounding the su
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7

Zlatanov, Boyan. "On a generalization of tripled fixed or best proximity points for a class of cyclic contractive maps." Filomat 35, no. 9 (2021): 3015–31. http://dx.doi.org/10.2298/fil2109015z.

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We enrich the known results about tripled fixed points and tripled best proximity points. We generalize the notion of ordered pairs of cyclic contraction maps and we obtain sufficient conditions for the existence and uniqueness of fixed (or best proximity) points. We get a priori and a posteriori error estimates for the tripled fixed points and for the tripled best proximity points, provided that the underlying Banach space has modulus of convexity of power type in the case of best proximity points, obtained by sequences of successive iterations. We illustrate the main result with an example.
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8

Khoromskij, Boris, and Sergey Repin. "Rank Structured Approximation Method for Quasi-Periodic Elliptic Problems." Computational Methods in Applied Mathematics 17, no. 3 (2017): 457–77. http://dx.doi.org/10.1515/cmam-2017-0014.

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AbstractWe consider an iteration method for solving an elliptic type boundary value problem {\mathcal{A}u=f}, where a positive definite operator {\mathcal{A}} is generated by a quasi-periodic structure with rapidly changing coefficients (a typical period is characterized by a small parameter ϵ). The method is based on using a simpler operator {\mathcal{A}_{0}} (inversion of {\mathcal{A}_{0}} is much simpler than inversion of {\mathcal{A}}), which can be viewed as a preconditioner for {\mathcal{A}}. We prove contraction of the iteration method and establish explicit estimates of the contraction
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9

CASCON, J. MANUEL, RICARDO H. NOCHETTO, and KUNIBERT G. SIEBERT. "DESIGN AND CONVERGENCE OF AFEM IN H(DIV)." Mathematical Models and Methods in Applied Sciences 17, no. 11 (2007): 1849–81. http://dx.doi.org/10.1142/s0218202507002492.

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We design an adaptive finite element method (AFEM) for mixed boundary value problems associated with the differential operator A-∇div in H(div, Ω). For A being a variable coefficient matrix with possible jump discontinuities, we provide a complete a posteriori error analysis which applies to both Raviart–Thomas ℝ𝕋n and Brezzi–Douglas–Marini 𝔹𝔻𝕄n elements of any order n in dimensions d = 2, 3. We prove a strict reduction of the total error between consecutive iterates, namely a contraction property for the sum of energy error and oscillation, the latter being solution-dependent. We present nume
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10

Haberl, Alexander, Dirk Praetorius, Stefan Schimanko, and Martin Vohralík. "Convergence and quasi-optimal cost of adaptive algorithms for nonlinear operators including iterative linearization and algebraic solver." Numerische Mathematik 147, no. 3 (2021): 679–725. http://dx.doi.org/10.1007/s00211-021-01176-w.

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AbstractWe consider a second-order elliptic boundary value problem with strongly monotone and Lipschitz-continuous nonlinearity. We design and study its adaptive numerical approximation interconnecting a finite element discretization, the Banach–Picard linearization, and a contractive linear algebraic solver. In particular, we identify stopping criteria for the algebraic solver that on the one hand do not request an overly tight tolerance but on the other hand are sufficient for the inexact (perturbed) Banach–Picard linearization to remain contractive. Similarly, we identify suitable stopping
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11

Botterman, B. R., G. A. Iwamoto, and W. J. Gonyea. "Classification of motor units in flexor carpi radialis muscle of the cat." Journal of Neurophysiology 54, no. 3 (1985): 676–90. http://dx.doi.org/10.1152/jn.1985.54.3.676.

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Motor units in the cat flexor carpi radialis (FCR) muscle, one of two primary wrist flexors, were classified into three groups: slow twitch, fatigue resistant (S); fast twitch, fatigue resistant (FR); and fast twitch, fatigue sensitive (FF). Classification was based on 1) the ratio of the tension-time area produced by a train of stimuli delivered at 40 pps and the maximum tension-time area (A40/Amax), and 2) the cumulative force index (CFI), calculated from a series of trains (40 pps) delivered intermittently for a period of 4 min. The CFI is defined as the ratio between the force accumulated
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12

Gong, Wei, Zhiyu Tan, and Zhaojie Zhou. "Optimal convergence of finite element approximation to an optimization problem with PDE constraint*." Inverse Problems 38, no. 4 (2022): 045004. http://dx.doi.org/10.1088/1361-6420/ac4f5c.

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Abstract We study in this paper the optimal convergence of finite element approximation to an optimization problem with PDE constraint. Specifically, we consider an elliptic distributed optimal control problem without control constraints, which can also be viewed as a regularized inverse source problem. The main contributions are two-fold. First, we derive a priori and a posteriori error estimates for the optimization problems, under an appropriately chosen norm that allows us to establish an isomorphism between the solution space and its dual. These results yield error estimates with explicit
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13

Okai, Liria Akie, and André Fabio Kohn. "Quantifying the Contributions of the Flexor Digitorum Brevis Muscle on Postural Stability." Motor Control 19, no. 3 (2015): 161–72. http://dx.doi.org/10.1123/mc.2013-0066.

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Surprisingly little attention has been devoted to the role played by the intrinsic muscles of the human foot. The aim of this study was to quantify the capabilities of the flexor digitorum brevis (FDB) muscle to contribute to upright postural control. The approaches consisted of analysis of the effects of FDB contraction elicited by external electrical stimulation and quantification of the magnitude of FDB torque generation. The results showed the FDB can produce significant changes in static posture by itself as shown by changes in the center of pressure. Moreover, the FDB contribution to cou
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14

Buffa, Annalisa, and Carlotta Giannelli. "Adaptive isogeometric methods with hierarchical splines: Error estimator and convergence." Mathematical Models and Methods in Applied Sciences 26, no. 01 (2015): 1–25. http://dx.doi.org/10.1142/s0218202516500019.

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The problem of developing an adaptive isogeometric method (AIGM) for solving elliptic second-order partial differential equations with truncated hierarchical B-splines of arbitrary degree and different order of continuity is addressed. The adaptivity analysis holds in any space dimensions. We consider a simple residual-type error estimator for which we provide a posteriori upper and lower bound in terms of local error indicators, taking also into account the critical role of oscillations as in a standard adaptive finite element setting. The error estimates are properly combined with a simple m
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15

Napadow, Vitaly J., Qun Chen, Van J. Wedeen, and Richard J. Gilbert. "Biomechanical basis for lingual muscular deformation during swallowing." American Journal of Physiology-Gastrointestinal and Liver Physiology 277, no. 3 (1999): G695—G701. http://dx.doi.org/10.1152/ajpgi.1999.277.3.g695.

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Our goal was to quantify intramural mechanics in the tongue through an assessment of local strain during the physiological phases of swallowing. Subjects were imaged with an ultrafast gradient echo magnetic resonance imaging (MRI) pulse sequence after the application of supersaturated magnetized bands in the x and y directions. Local strain was defined through deformation of discrete triangular elements defined by these bands and was depicted graphically either as color-coded two-dimensional strain maps or as three-dimensional octahedra whose axes correspond to the principal strains for each e
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16

Wood, C. E. "ACTH, cortisol, and renin responses to arterial hypotension in sheep." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 251, no. 1 (1986): R18—R22. http://dx.doi.org/10.1152/ajpregu.1986.251.1.r18.

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This study was designed to investigate adrenocorticotropin (ACTH), cortisol, and renin responses to nitroprusside-induced hypotension in adult sheep. Five sheep were surgically prepared with carotid arterial skin loops at least 1 yr before these experiments. After catheterization of the carotid arteries and external jugular veins the sheep were infused with nitroprusside intravenously at rates of 0, 10, 15, or 20 micrograms . kg-1 . min-1 for 10 min. Nitroprusside produced significantly dose-related decreases in mean arterial pressure and increases in heart rate, plasma ACTH and cortisol conce
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17

Templeton, G. H., G. B. Seibert, M. Ramanathan, S. S. Cassidy, and R. Johnson. "Left ventricular coordinate systems." American Journal of Physiology-Heart and Circulatory Physiology 257, no. 3 (1989): H1025—H1031. http://dx.doi.org/10.1152/ajpheart.1989.257.3.h1025.

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Three-dimensional kinematics of radiopaque markers in anterior, posterior, septal, and lateral regions of a major equatorial plane were evaluated in anesthetized dogs by biplane fluoroscopy. Stationary coordinate systems measured marker locations recorded during diastole and systole from a contractile origin at the center of contraction at end systole and from a geometric origin at the intersection with the equatorial plane of the ventricular long axis at end diastole. A time-indexed system measured marker locations at end diastole and at end systole, respectively, from the locations of the ge
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18

Call, Jarrod A., Michael D. Eckhoff, Kristen A. Baltgalvis, Gordon L. Warren, and Dawn A. Lowe. "Adaptive strength gains in dystrophic muscle exposed to repeated bouts of eccentric contraction." Journal of Applied Physiology 111, no. 6 (2011): 1768–77. http://dx.doi.org/10.1152/japplphysiol.00942.2011.

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The objective of this study was to determine the functional recovery and adaptation of dystrophic muscle to multiple bouts of contraction-induced injury. Because lengthening (i.e., eccentric) contractions are extremely injurious for dystrophic muscle, it was considered that repeated bouts of such contractions would exacerbate the disease phenotype in mdx mice. Anterior crural muscles (tibialis anterior and extensor digitorum longus) and posterior crural muscles (gastrocnemius, soleus, and plantaris) from mdx mice performed one or five repeated bouts of 100 electrically stimulated eccentric con
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19

Knight, D. R., Y. T. Shen, J. X. Thomas, W. C. Randall, and S. F. Vatner. "Sympathetic activation induces asynchronous contraction in awake dogs with regional denervation." American Journal of Physiology-Heart and Circulatory Physiology 255, no. 2 (1988): H358—H365. http://dx.doi.org/10.1152/ajpheart.1988.255.2.h358.

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To determine effects of regional left ventricular (LV) denervation on regional contractile responses to sympathetic activation, dogs with posterior LV wall denervation (posterior wall-denervated group) and dogs with innervated posterior LV walls (intact group) were studied during excitement, exercise, bilateral sympathetic nerve stimulation, and norepinephrine infusion. In intact conscious dogs, all modes of sympathetic activation increased the magnitude and decreased the time of onset of systolic wall thickening (WT) similarly in the anterior and posterior wall. In the denervated group, excit
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20

Cooper, Donald S., Maisie Shindo, Malcolm H. Hast, Uttam Sinha, and Dale H. Rice. "Dynamic Properties of the Posterior Cricoarytenoid Muscle." Annals of Otology, Rhinology & Laryngology 103, no. 12 (1994): 937–44. http://dx.doi.org/10.1177/000348949410301203.

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The aim of this research was to investigate the contractile properties of the posterior cricoarytenoid (PCA) muscle. Simultaneous measurements were made of the isometric force, temperature, and electromyographic activity of the dorsal cricoarytenoid muscle of anesthetized dogs during supramaximal stimulation of the recurrent laryngeal nerve for twitch and tetanic contraction. The conduction delay between stimulation of the recurrent nerve at the level of the larynx and the onset of the muscle action potential averaged 2.0 ± 0.2 milliseconds (ms), and the latent period between the onset of elec
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21

Bauer, R. M., G. A. Iwamoto, and T. G. Waldrop. "Ventrolateral medullary neurons modulate pressor reflex to muscular contraction." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 257, no. 5 (1989): R1154—R1161. http://dx.doi.org/10.1152/ajpregu.1989.257.5.r1154.

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Cardiorespiratory alterations during exercise are mediated through feedback from contracting muscles and descending drive from rostral brain sites such as the posterior hypothalamus. The role of medullary sites, which process this information, was examined in this study. In anesthetized cats, muscular contraction elicited by stimulation of L7 and S1 ventral roots and electrical stimulation of sites in the posterior hypothalamus both evoked increases in arterial pressure, heart rate, and minute ventilation. The reflex increase in arterial pressure produced by muscular contraction was attenuated
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22

Yoganathan, Ajit P., Jack D. Lemmon, Young H. Kim, Peter G. Walker, Robert A. Levine, and Carol C. Vesier. "A Computational Study of a Thin-Walled Three-Dimensional Left Ventricle During Early Systole." Journal of Biomechanical Engineering 116, no. 3 (1994): 307–14. http://dx.doi.org/10.1115/1.2895735.

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A numerical study was conducted to solve the three-dimensional Navier-Stokes equations for time-dependent flow in a compliant thin-walled, anatomically correct left ventricle during early systole. Model parameters were selected so that the simulation results could be compared to clinical data. The results produced endocardial wall motion which was consistent with human heart data, and velocity fields consistent with those occurring in a normally-contracting left ventricle. During isovolumetric contraction the posterior wall moved basally and posteriorly, while the septal wall moved apically an
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23

Cheeney, Gregory, Jose M. Remes-Troche, Ashok Attaluri, and Satish S. C. Rao. "Investigation of anal motor characteristics of the sensorimotor response (SMR) using 3-D anorectal pressure topography." American Journal of Physiology-Gastrointestinal and Liver Physiology 300, no. 2 (2011): G236—G240. http://dx.doi.org/10.1152/ajpgi.00348.2010.

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Desire to defecate is associated with a unique anal contractile response, the sensorimotor response (SMR). However, the precise muscle(s) involved is not known. We aimed to examine the role of external and internal anal sphincter and the puborectalis muscle in the genesis of SMR. Anorectal 3-D pressure topography was performed in 10 healthy subjects during graded rectal balloon distention using a novel high-definition manometry system consisting of a probe with 256 pressure sensors arranged circumferentially. The anal pressure changes before, during, and after the onset of SMR were measured at
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24

Kieser, D. C., E. Savage, and P. Sharplin. "A Positive Quadriceps Active Test, without the Quadriceps Being Active." Case Reports in Orthopedics 2019 (December 28, 2019): 1–4. http://dx.doi.org/10.1155/2019/6135632.

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Case. A 55-year-old male with a chronic isolated grade 3 PCL injury who demonstrates a positive quadriceps active test without activating his quadriceps musculature. Conclusion. Gravity and hamstring contraction posteriorly translate the tibia into a subluxed position. Subsequent gastrocnemius contraction with the knee flexed causes an anterior tibial translation by virtue of the mass enlargement of the gastrocnemius muscular bulk, the string of a bow effect, and the anterior origin of the gastrocnemius in relation to the posterior border of the subluxed tibia aided by the normal posterior tib
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25

Bokhove, Onno, Anna Kalogirou, David Henry, and Gareth P. Thomas. "A novel wave-energy device with enhanced wave amplification and induction actuator." International Marine Energy Journal 3, no. 1 (2020): 37–44. http://dx.doi.org/10.36688/imej.3.37-44.

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A novel wave-energy device is presented. Both a preliminary proof-of-principle of a working, scaled laboratory version of the energy device is shown as well as the derivation and analysis of a comprehensive mathematical and numerical model of the new device. The wave-energy device includes a convergence in which the waves are amplified, a constrained wave buoy with a (curved) mast and direct energy conversion of the buoy motion into electrical power via an electro-magnetic generator. The device is designed for use in breakwaters and it is possible to be taken out of action during severe weathe
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26

Clark, Robert A., and Joseph L. Demer. "Functional morphometry demonstrates extraocular muscle compartmental contraction during vertical gaze changes." Journal of Neurophysiology 115, no. 1 (2016): 370–78. http://dx.doi.org/10.1152/jn.00825.2015.

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Anatomical studies demonstrate selective compartmental innervation of most human extraocular muscles (EOMs), suggesting the potential for differential compartmental control. This was supported by magnetic resonance imaging (MRI) demonstrating differential lateral rectus (LR) compartmental contraction during ocular counterrolling, differential medial rectus (MR) compartmental contraction during asymmetric convergence, and differential LR, inferior rectus (IR), and superior oblique (SO) compartmental contraction during vertical vergence. To ascertain possible differential compartmental EOM contr
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27

Sasada, Syusaku, Toshiki Tazoe, Tsuyoshi Nakajima, E. Paul Zehr, and Tomoyoshi Komiyama. "Effects of Leg Pedaling on Early Latency Cutaneous Reflexes in Upper Limb Muscles." Journal of Neurophysiology 104, no. 1 (2010): 210–17. http://dx.doi.org/10.1152/jn.00774.2009.

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The functional coupling of neural circuits between the upper and lower limbs involving rhythmic movements is of interest to both motor control research and rehabilitation science. This coupling can be detected by examining the effect of remote rhythmic limb movement on the modulation of reflex amplitude in stationary limbs. The present study investigated the extent to which rhythmic leg pedaling modulates the amplitude of an early latency (peak 30–70 ms) cutaneous reflex (ELCR) in the upper limb muscles. Thirteen neurologically intact volunteers performed leg pedaling (60 or 90 rpm) while simu
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28

Conrad, P. A., K. A. Giuliano, G. Fisher, K. Collins, P. T. Matsudaira, and D. L. Taylor. "Relative distribution of actin, myosin I, and myosin II during the wound healing response of fibroblasts." Journal of Cell Biology 120, no. 6 (1993): 1381–91. http://dx.doi.org/10.1083/jcb.120.6.1381.

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Myosin I is present in Swiss 3T3 fibroblasts and its localization reflects a possible involvement in the extension and/or retraction of protrusions at the leading edge of locomoting cells and the transport of vesicles, but not in the contraction of stress fibers or transverse fibers. An affinity-purified polyclonal antibody to brush border myosin I colocalizes with a polypeptide of 120 kD in fibroblast extracts. Within initial protrusions of polarized, migrating fibroblasts, myosin I exhibits a punctate distribution, whereas actin is diffuse and myosin II is absent. Myosin I also exists in lin
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29

Tanoi, Chiharu, Yoshio Suzuki, Masato Shibuya, Kenichiro Sugita, Kaoru Masuzawa, and Masahisa Asano. "Mechanism of the Enhanced Vasoconstrictor Responses to Endothelin-1 in Canine Cerebral Arteries." Journal of Cerebral Blood Flow & Metabolism 11, no. 3 (1991): 371–79. http://dx.doi.org/10.1038/jcbfm.1991.77.

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Vasoconstrictor effects of endothelin-1 (ET) were investigated in endothelium-denuded strips of cerebral (basilar and posterior cerebral) and mesenteric arteries of the dog. ET produced a concentration-dependent contraction in these arteries. Contractile responses to lower concentrations (below 3 × 10−10 M) of ET were significantly greater in the cerebral arteries than in the mesenteric artery. Inhibition by nifedipine of the contractile responses to ET was greater in the basilar artery than in the mesenteric artery. After the inhibition by 10−7 M nifedipine, the remaining responses to ET were
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30

Morano, Alexander A., Ilzat Ali, and Jeffrey D. Dvorin. "Elucidating the Spatio-Temporal dynamics of the Plasmodium falciparum basal complex." PLOS Pathogens 20, no. 6 (2024): e1012265. http://dx.doi.org/10.1371/journal.ppat.1012265.

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Asexual replication of Plasmodium falciparum occurs via schizogony, wherein 16–36 daughter cells are produced within the parasite during one semi-synchronized cytokinetic event. Schizogony requires a divergent contractile ring structure known as the basal complex. Our lab has previously identified PfMyoJ (PF3D7_1229800) and PfSLACR (PF3D7_0214700) as basal complex proteins recruited midway through segmentation. Using ultrastructure expansion microscopy, we localized both proteins to a novel basal complex subcompartment. While both colocalize with the basal complex protein PfCINCH upon recruitm
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31

Campanelli, J. T., and R. H. Scheller. "Histidine-rich basic peptide: a cardioactive neuropeptide from Aplysia neurons R3-14." Journal of Neurophysiology 57, no. 4 (1987): 1201–9. http://dx.doi.org/10.1152/jn.1987.57.4.1201.

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We have previously demonstrated that neurons R3-14 of the Aplysia abdominal ganglia specifically express a gene encoding a 108-amino acid neuropeptide precursor. This precursor is postranslationally processed by cleavage of a signal sequence and two internal dibasic residues resulting in three peptides. The peptide products are colocalized in dense core granules throughout the R3-14 processes that innervate the efferent vein of the gill and the auricle. Gel filtration and reverse phase high-pressure liquid chromatography (rpHPLC) were used to purify a 4.9-kDa peptide produced by the R3-14 neur
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32

Lafleur, J., D. Zytnicki, G. Horcholle-Bossavit, and L. Jami. "Declining inhibition elicited in cat lumbar motoneurons by repetitive stimulation of group II muscle afferents." Journal of Neurophysiology 70, no. 5 (1993): 1805–10. http://dx.doi.org/10.1152/jn.1993.70.5.1805.

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1. The aim of the present experiments was to verify whether group II inputs from gastrocnemius medialis (GM) muscle could elicit declining inhibitions similar to those observed during GM contractions in a variety of lumbar motoneurons of the cat spinal cord. Motoneurons were recorded intracellularly in chloralose- or pentobarbitone-anesthetized preparations during electrical stimulation of GM nerve with repetitive trains. 2. With strengths in the group I range, repetitive stimulation evoked the usual Ia excitation in homonymous motoneurons and excitatory postsynaptic potential (EPSP) amplitude
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33

Kambhampati, Srinivas B. S., and Bharat Guthikonda. "The pushed quadriceps active test – A modification of the quadriceps active test to diagnose PCL deficiency." Journal of Arthroscopic Surgery and Sports Medicine 2 (June 30, 2021): 128–30. http://dx.doi.org/10.25259/jassm_9_2021.

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Quadriceps active (QA) test has been described and well known for the diagnosis of posterior cruciate ligament (PCL) deficiency. We describe a modification of the QA test to diagnose PCL deficiency. Pushed QA test consists of two components where the examiner pushes the proximal tibia posteriorly with the knee flexed <90° in the first part of the test translating the tibia posteriorly like in the posterior drawer test while the patient reduces the translation actively by contracting the quadriceps in the second part like in the QA test.
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34

Martin, Adam C., Michael Gelbart, Rodrigo Fernandez-Gonzalez, Matthias Kaschube, and Eric F. Wieschaus. "Integration of contractile forces during tissue invagination." Journal of Cell Biology 188, no. 5 (2010): 735–49. http://dx.doi.org/10.1083/jcb.200910099.

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Contractile forces generated by the actomyosin cytoskeleton within individual cells collectively generate tissue-level force during epithelial morphogenesis. During Drosophila mesoderm invagination, pulsed actomyosin meshwork contractions and a ratchet-like stabilization of cell shape drive apical constriction. Here, we investigate how contractile forces are integrated across the tissue. Reducing adherens junction (AJ) levels or ablating actomyosin meshworks causes tissue-wide epithelial tears, which release tension that is predominantly oriented along the anterior–posterior (a-p) embryonic ax
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Ramirez-Estudillo, Abel, Karla Torres-Navarro, Sergio Rojas-Juárez, Ximena Ramirez-Galicia, Berenice Palafox-Cornejo, and Adriana Galicia-Castillo. "Case Report: Fibroglial Retinal Tissue in Contractile Morning Glory Disc Anomaly." Case Reports in Ophthalmology 12, no. 2 (2021): 525–30. http://dx.doi.org/10.1159/000510958.

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The purpose of the present case is to describe a patient with tractional retinal detachment (RD) associated with contractile morning glory: a 17-year-old female, with a history of failed surgery for RD when she was 2 years old in her right eye (OD), nystagmus, and a limited visual acuity in the left eye (OS). The slit lamp examination showed phthisis bulbi in OD and the anterior segment was unremarkable in OS. Dilated fundus examination revealed a tractional RD in the posterior pole and peripapillary and preretinal fibrosis without evidence of intravitreal dispersion of retinal pigment epithel
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Esbaugh, A. J., M. Hazel, and D. P. Toews. "Aspects of lymph-heart function in Rana catesbeiana." Canadian Journal of Zoology 80, no. 12 (2002): 2125–30. http://dx.doi.org/10.1139/z02-210.

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The effect of voluntary dives on the posterior lymph heart rate of the bullfrog, Rana catesbeiana, was tested and compared with the blood-heart rate (n = 6). This was performed by cannulating the posterior lymph heart and femoral artery simultaneously. Blood-heart rates during submergence were significantly lower (α = 0.05) then pre-submergence rates at all sampling times. In contrast, the lymph hearts showed significantly lower rates only during the first and last submergence intervals. It is believed that the lymph-heart bradycardia found during these intervals is due in part to the physiolo
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Lentle, R. G., G. W. Reynolds, C. M. Hulls, and J. P. Chambers. "Advanced spatiotemporal mapping methods give new insights into the coordination of contractile activity in the stomach of the rat." American Journal of Physiology-Gastrointestinal and Liver Physiology 311, no. 6 (2016): G1064—G1075. http://dx.doi.org/10.1152/ajpgi.00308.2016.

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We used spatiotemporal mapping of strain rate to determine the direction of propagation and amplitudes of the longitudinal and circumferential components of antrocorporal (AC) contractions and fundal contractions in the rat stomach maintained ex vivo and containing a volume of fluid that was within its normal functional capacity. In the region of the greater curvature the longitudinal and circular components of AC contractions propagated synchronously at right angles to the arciform geometric axis of the stomach. However, the configuration of AC contractions was U shaped, neither the circular
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Devost, Dominic, and Hans H. Zingg. "Novel in vitro system for functional assessment of oxytocin action." American Journal of Physiology-Endocrinology and Metabolism 292, no. 1 (2007): E1—E6. http://dx.doi.org/10.1152/ajpendo.00529.2005.

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One of the classical biological actions mediated by the posterior pituitary hormone oxytocin (OT) is contraction of the uterus at parturition. Moreover, premature activation of the OT system is thought to contribute to preterm labor, a major clinical problem in obstetrical practice. However, the molecular mechanisms linking activation of the OT receptor (OTR) to myometrial contractions are not fully understood. Here, we describe an in vitro system that should serve as a useful tool to study this question at a cellular level. The system consists of a collagen lattice contraction assay and two d
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Wagner, Jamie, Erik Allman, Ashley Taylor, et al. "A calcineurin homologous protein is required for sodium-proton exchange events in the C. elegans intestine." American Journal of Physiology-Cell Physiology 301, no. 6 (2011): C1389—C1403. http://dx.doi.org/10.1152/ajpcell.00139.2011.

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Caenorhabditis elegans defecation is a rhythmic behavior, composed of three sequential muscle contractions, with a 50-s periodicity. The motor program is driven by oscillatory calcium signaling in the intestine. Proton fluxes, which require sodium-proton exchangers at the apical and basolateral intestinal membranes, parallel the intestinal calcium flux. These proton shifts are critical for defecation-associated muscle contraction, nutrient uptake, and longevity. How sodium-proton exchangers are activated in time with intestinal calcium oscillation is not known. The posterior body defecation co
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Lloyd, R., L. Jugé, and L. Bilston. "O043 Investigating Upper-Airway Mechanics with Computational Tongue Models." Sleep Advances 4, Supplement_1 (2023): A16—A17. http://dx.doi.org/10.1093/sleepadvances/zpad035.043.

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Abstract With the use of computational models of the oral cavity, we aim to understand how changes in the morphology of the oral cavity and changes the stiffness of the tongue affect the movement of the posterior surface of the tongue. Anatomical and diffusion weighted imaging from 20 healthy individuals (10M:10F, Age: 22-54years, BMI: 17-30kg/m²), were used to develop 3D models of the tongue including the fibre orientations of the tongue muscles. All models were aligned and scaled to match the volume of the average subject's mandible, so that only differences in shape were modelled. The muscl
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Mørk, Halvor K., Ivar Sjaastad, Ole M. Sejersted, and William E. Louch. "Slowing of cardiomyocyte Ca2+ release and contraction during heart failure progression in postinfarction mice." American Journal of Physiology-Heart and Circulatory Physiology 296, no. 4 (2009): H1069—H1079. http://dx.doi.org/10.1152/ajpheart.01009.2008.

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Deterioration of cardiac contractility during congestive heart failure (CHF) is believed to involve decreased function of individual cardiomyocytes and may include reductions in contraction magnitude and/or kinetics. We examined the progression of in vivo and in vitro alterations in contractile function in CHF mice and investigated underlying alterations in Ca2+ homeostasis. Following induction of myocardial infarction (MI), mice with CHF were examined at early (1 wk post-MI) and chronic (10 wk post-MI) stages of disease development. Sham-operated mice served as controls. Global and local left
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Padda, Bikram S., Sung-Ae Jung, Dolores Pretorius, Charles W. Nager, Debbie Den-Boer, and Ravinder K. Mittal. "Effects of pelvic floor muscle contraction on anal canal pressure." American Journal of Physiology-Gastrointestinal and Liver Physiology 292, no. 2 (2007): G565—G571. http://dx.doi.org/10.1152/ajpgi.00250.2006.

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The role of pelvic floor muscle contraction in the genesis of anal canal pressure is not clear. Recent studies have suggested that vaginal distension increases pelvic floor muscle contraction. We studied the effects of vaginal distension on anal canal pressure in 15 nullipara asymptomatic women. Anal pressure, rest, and squeeze were measured using station pull-through manometry techniques with no vaginal probe, a 10-mm vaginal probe, and a 25-mm vaginal probe in place. Rest and squeeze vaginal pressures were significantly higher when measured with the 25-mm probe compared with the 10-mm probe,
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Towse, Theodore F., Jill M. Slade, and Ronald A. Meyer. "Effect of physical activity on MRI-measured blood oxygen level-dependent transients in skeletal muscle after brief contractions." Journal of Applied Physiology 99, no. 2 (2005): 715–22. http://dx.doi.org/10.1152/japplphysiol.00272.2005.

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The signal intensity (SI) in gradient-echo, echo-planar magnetic resonance images (repetition time/echo time = 1,000/40) of anterior tibialis muscle in active [estimated energy expenditure 42.4 ± 3.7 (SD), n = 8] vs. sedentary (32.3 ± 0.6 kcal·kg−1·day−1, n = 8) young adult (18–34 yr old) human subjects was measured after single, 1-s-duration maximum voluntary ankle dorsiflexion contractions. There was no difference between groups in anterior tibial muscle cross-sectional area or peak force. In both groups there was a transient increase in anterior tibialis muscle SI, which peaked 5–7 s after
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Xu, Liang, Xi Wei Xie, and Jost B. Jonas. "Posterior Vitreous Contraction After Cerebral Sinus Thrombosis." Ophthalmic Surgery, Lasers, and Imaging 40, no. 6 (2009): 600–601. http://dx.doi.org/10.3928/15428877-20091030-13.

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van der Pas, Stéphanie, Botond Szabó, and Aad van der Vaart. "Adaptive posterior contraction rates for the horseshoe." Electronic Journal of Statistics 11, no. 2 (2017): 3196–225. http://dx.doi.org/10.1214/17-ejs1316.

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Reiß, Markus, and Johannes Schmidt-Hieber. "Posterior contraction rates for support boundary recovery." Stochastic Processes and their Applications 130, no. 11 (2020): 6638–56. http://dx.doi.org/10.1016/j.spa.2020.06.005.

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Gao, Chao, and Harrison H. Zhou. "Rate-optimal posterior contraction for sparse PCA." Annals of Statistics 43, no. 2 (2015): 785–818. http://dx.doi.org/10.1214/14-aos1268.

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Shen, Weining, and Subhashis Ghosal. "Posterior Contraction Rates of Density Derivative Estimation." Sankhya A 79, no. 2 (2017): 336–54. http://dx.doi.org/10.1007/s13171-017-0105-7.

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Ghosh, Prasenjit, Debdeep Pati, and Anirban Bhattacharya. "Posterior Contraction Rates for Stochastic Block Models." Sankhya A 82, no. 2 (2019): 448–76. http://dx.doi.org/10.1007/s13171-019-00180-5.

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Hartley, Olan, Tanvi Shanbhag, Derek Smith, et al. "The Effect of Stacking on the Accuracy of 3D-Printed Full-Arch Dental Models." Polymers 14, no. 24 (2022): 5465. http://dx.doi.org/10.3390/polym14245465.

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The objective of this study was to assess the effect of stacking on the dimensional and full-arch accuracy of 3D-printed models, utilising a standardised assessment methodology. A previously validated methodology involving a standard tessellation language image (STL) reference model, comprising seven spheres on a horseshoe base resembling a dental arch, was used. Six 3D-designed STL models were prepared, optimised, and stacked horizontally using 3D Sprint software. The stacking file was transferred to the NextDent 5100 printer to build the physical models. To assess accuracy, a coordinate meas
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