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Sample records for extrinsic forelimb muscles

  1. Representation of individual forelimb muscles in primary motor cortex.

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    Hudson, Heather M; Park, Michael C; Belhaj-Saïf, Abderraouf; Cheney, Paul D

    2017-07-01

    Stimulus-triggered averaging (StTA) of forelimb muscle electromyographic (EMG) activity was used to investigate individual forelimb muscle representation within the primary motor cortex (M1) of rhesus macaques with the objective of determining the extent of intra-areal somatotopic organization. Two monkeys were trained to perform a reach-to-grasp task requiring multijoint coordination of the forelimb. EMG activity was simultaneously recorded from 24 forelimb muscles including 5 shoulder, 7 elbow, 5 wrist, 5 digit, and 2 intrinsic hand muscles. Microstimulation (15 µA at 15 Hz) was delivered throughout the movement task and individual stimuli were used as triggers for generating StTAs of EMG activity. StTAs were used to map the cortical representations of individual forelimb muscles. As reported previously (Park et al. 2001), cortical maps revealed a central core of distal muscle (wrist, digit, and intrinsic hand) representation surrounded by a horseshoe-shaped proximal (shoulder and elbow) muscle representation. In the present study, we found that shoulder and elbow flexor muscles were predominantly represented in the lateral branch of the horseshoe whereas extensors were predominantly represented in the medial branch. Distal muscles were represented within the core distal forelimb representation and showed extensive overlap. For the first time, we also show maps of inhibitory output from motor cortex, which follow many of the same organizational features as the maps of excitatory output.NEW & NOTEWORTHY While the orderly representation of major body parts along the precentral gyrus has been known for decades, questions have been raised about the possible existence of additional more detailed aspects of somatotopy. In this study, we have investigated this question with respect to muscles of the arm and show consistent features of within-arm (intra-areal) somatotopic organization. For the first time we also show maps of how inhibitory output from motor cortex is

  2. Locomotor function of forelimb protractor and retractor muscles of dogs: evidence of strut-like behavior at the shoulder.

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    Carrier, David R; Deban, Stephen M; Fischbein, Timna

    2008-01-01

    The limbs of running mammals are thought to function as inverted struts. When mammals run at constant speed, the ground reaction force vector appears to be directed near the point of rotation of the limb on the body such that there is little or no moment at the joint. If this is true, little or no external work is done at the proximal joints during constant-speed running. This possibility has important implications to the energetics of running and to the coupling of lung ventilation to the locomotor cycle. To test if the forelimb functions as an inverted strut at the shoulder during constant-speed running and to characterize the locomotor function of extrinsic muscles of the forelimb, we monitored changes in the recruitment of six muscles that span the shoulder (the m. pectoralis superficialis descendens, m. pectoralis profundus, m. latissimus dorsi, m. omotransversarius, m. cleidobrachialis and m. trapezius) to controlled manipulations of locomotor forces and moments in trotting dogs (Canis lupus familiaris Linnaeus 1753). Muscle activity was monitored while the dogs trotted at moderate speed (approximately 2 m s(-1)) on a motorized treadmill. Locomotor forces were modified by (1) adding mass to the trunk, (2) inclining the treadmill so that the dogs ran up- and downhill (3) adding mass to the wrists or (4) applying horizontally directed force to the trunk through a leash. When the dogs trotted at constant speed on a level treadmill, the primary protractor muscles of the forelimb exhibited activity during the last part of the ipsilateral support phase and the beginning of swing phase, a pattern that is consistent with the initiation of swing phase but not with active protraction of the limb during the beginning of support phase. Results of the force manipulations were also consistent with the protractor muscles initiating swing phase and contributing to active braking via production of a protractor moment on the forelimb when the dogs decelerate. A similar

  3. Repositioning forelimb superficialis muscles: tendon attachment and muscle activity enable active relocation of functional myofibers.

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    Huang, Alice H; Riordan, Timothy J; Wang, Lingyan; Eyal, Shai; Zelzer, Elazar; Brigande, John V; Schweitzer, Ronen

    2013-09-16

    The muscles that govern hand motion are composed of extrinsic muscles that reside within the forearm and intrinsic muscles that reside within the hand. We find that the extrinsic muscles of the flexor digitorum superficialis (FDS) first differentiate as intrinsic muscles within the hand and then relocate as myofibers to their final position in the arm. This remarkable translocation of differentiated myofibers across a joint is dependent on muscle contraction and muscle-tendon attachment. Interestingly, the intrinsic flexor digitorum brevis (FDB) muscles of the foot are identical to the FDS in tendon pattern and delayed developmental timing but undergo limited muscle translocation, providing strong support for evolutionary homology between the FDS and FDB muscles. We propose that the intrinsic FDB pattern represents the original tetrapod limb and that translocation of the muscles to form the FDS is a mammalian evolutionary addition.

  4. Equine postanesthetic forelimb lameness: intracompartmental muscle pressure changes and biochemical patterns.

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    Lindsay, W A; McDonell, W; Bignell, W

    1980-12-01

    Intracompartmental muscle pressures were recorded from the right and left forelimbs (extensor carpi radialis, triceps brachii) of healthy horses maintained in left lateral recumbency while under deep halothane anesthesia for 180 to 240 minutes. Cardiac output, blood pressure, blood gases, and acid-base status were monitored throughout the anesthesia, and electrolyte levels (Ca2+, P+, K+, Cl-, Na+) and enzyme activities (aspartate aminotransferase (AST), creatine phosphokinase (CPK), and blood lactate) were monitored for 7 days. Postanesthetic forelimb lameness was produced in 5 of the 6 horses with this prolonged anesthetic regime. This lameness was associated with muscle plaque formation and clinical signs which were similar to the forelimb lameness sometimes seen in horses after surgical anesthesia. Plasma protein, serum calcium, plasma sodium, and blood urea nitrogen concentrations did not change, whereas significantly increased hematocrit, plasma potassium, and serum inorganic phosphate values were seen at the end of anesthesia, along with a decrease in plasma chloride values. Blood lactate, serum AST, and serum CPK activities were significantly high in the postanesthetic period, although the sequence of the changes differed. Intracompartmental muscle pressures were higher in the left forelimb adjacent to the floor (contact limb), and in the instance of the triceps of the contact limb, the pressures were sufficiently high (greater than 30 mm of Hg) that they may have compromised capillary blood flow. However, these high intracompartmental muscle pressures did not persist when positional changes of the horses were introduced at the end of the anesthetic period. There was no correlation between the severity of postanesthetic lameness and any of the measured values. The results demonstrate an experimentally induced postanesthetic lameness which was primarily related to the development of a myositis. Although the causative factors of this myositis may be multiple

  5. Extrinsic versus intrinsic hand muscle dominance in finger flexion.

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    Al-Sukaini, A; Singh, H P; Dias, J J

    2016-05-01

    This study aims to identify the patterns of dominance of extrinsic or intrinsic muscles in finger flexion during initiation of finger curl and mid-finger flexion. We recorded 82 hands of healthy individuals (18-74 years) while flexing their fingers and tracked the finger joint angles of the little finger using video motion tracking. A total of 57 hands (69.5%) were classified as extrinsic dominant, where the finger flexion was initiated and maintained at proximal interphalangeal and distal interphalangeal joints. A total of 25 (30.5%) were classified as intrinsic dominant, where the finger flexion was initiated and maintained at the metacarpophalangeal joint. The distribution of age, sex, dominance, handedness and body mass index was similar in the two groups. This knowledge may allow clinicians to develop more efficient rehabilitation regimes, since intrinsic dominant individuals would not initiate extrinsic muscle contraction till later in finger flexion, and might therefore be allowed limited early active motion. For extrinsic dominant individuals, by contrast, initial contraction of extrinsic muscles would place increased stress on the tendon repair site if early motion were permitted. © The Author(s) 2016.

  6. Coordination of intrinsic and extrinsic foot muscles during walking.

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    Zelik, Karl E; La Scaleia, Valentina; Ivanenko, Yuri P; Lacquaniti, Francesco

    2015-04-01

    The human foot undergoes complex deformations during walking due to passive tissues and active muscles. However, based on prior recordings it is unclear if muscles that contribute to flexion/extension of the metatarsophalangeal (MTP) joints are activated synchronously to modulate joint impedance, or sequentially to perform distinct biomechanical functions. We investigated the coordination of MTP flexors and extensors with respect to each other, and to other ankle-foot muscles. We analyzed surface electromyographic (EMG) recordings of intrinsic and extrinsic foot muscles for healthy individuals during level treadmill walking, and also during sideways and tiptoe gaits. We computed stride-averaged EMG envelopes and used the timing of peak muscle activity to assess synchronous vs. sequential coordination. We found that peak MTP flexor activity occurred significantly before peak MTP extensor activity during walking (P walking tended to dissociate during other locomotor tasks. For instance, extensor hallucis brevis and extensor digitorum brevis muscle activation peaks decoupled during sideways gait. The sequential peak activity of MTP flexors followed by MTP extensors suggests that their biomechanical contributions may be largely separable from each other and from other extrinsic foot muscles during walking. Meanwhile, the task-specific coordination of the foot muscles during other modes of locomotion indicates a high-level of specificity in their function and control.

  7. Complete forelimb myology of the basal theropod dinosaur Tawa hallae based on a novel robust muscle reconstruction method.

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    Burch, Sara H

    2014-09-01

    The forelimbs of nonavian theropod dinosaurs have been the subject of considerable study and speculation due to their varied morphology and role in the evolution of flight. Although many studies on the functional morphology of a limb require an understanding of its musculature, comparatively little is known about the forelimb myology of theropods and other bipedal dinosaurs. Previous phylogenetically based myological reconstructions have been limited to the shoulder, restricting their utility in analyses of whole-limb function. The antebrachial and manual musculature in particular have remained largely unstudied due to uncertain muscular homologies in archosaurs. Through analysis of the musculature of extant taxa in a robust statistical framework, this study presents new hypotheses of homology for the distal limb musculature of archosaurs and provides the first complete reconstruction of dinosaurian forelimb musculature, including the antebrachial and intrinsic manual muscles. Data on the forelimb myology of a broad sample of extant birds, crocodylians, lizards, and turtles were analyzed using maximum likelihood ancestral state reconstruction and examined together with the osteology of the early theropod Tawa hallae from the Late Triassic of New Mexico to formulate a complete plesiomorphic myology for the theropod forelimb. Comparisons with previous reconstructions show that the shoulder musculature of basal theropods is more similar to that of basal ornithischians and sauropodomorphs than to that of dromaeosaurids. Greater development of the supracoracoideus and deltoideus musculature in theropods over other bipedal dinosaurs correlates with stronger movements of the forelimb at the shoulder and an emphasis on apprehension of relatively large prey. This emphasis is further supported by the morphology of the antebrachium and the intrinsic manual musculature, which exhibit a high degree of excursion and a robust morphology well-suited for powerful digital flexion

  8. Musculotopic organization of the motor neurons supplying forelimb and shoulder girdle muscles in the mouse.

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    Bácskai, Tímea; Fu, Yuhong; Sengul, Gulgun; Rusznák, Zoltán; Paxinos, George; Watson, Charles

    2013-01-01

    We identified the motor neurons (MNs) supplying the shoulder girdle and forelimb muscles in the C57BL/6J mouse spinal cord using Fluoro-Gold retrograde tracer injections. In spinal cord transverse sections from C2 to T2, we observed two MN columns (medial and lateral) both with ventral and dorsal subdivisions. The dorsolateral column consisted of the biceps brachii, forearm extensors, forearm flexors, and hand MNs, and the ventrolateral column consisted of the latissimus dorsi, trapezius, teres major, deltoid, and triceps MNs. The supraspinatus muscle MNs were located in the dorsomedial column, and pectoralis major and serratus anterior MNs were located in the ventromedial columns. MNs of the dorsolateral column innervated the biceps brachii in mid-C4 to mid-C7, forearm extensors in caudal C4 to mid-T1, forearm flexors in rostral C5 to mid-T1, and hand muscles in mid-C8 to mid-T2 segments. The MNs innervating the trapezius were located in mid-C2 to mid-C4, triceps brachii in mid-C6 to rostral T1, deltoid in rostral C4 to mid-C6, teres major in rostral C5 to mid-C8, and latissimus dorsi in mid-C5 to caudal C8. In addition, MNs innervating the supraspinatus were located from rostral C4 to caudal C8, pectoralis major in mid-C6 to mid-T2, and serratus anterior in rostral C5 to caudal C7/rostral C8 segments. While the musculotopic pattern of MN groups was very similar to that documented for other species, we found differences in the position and cranio-caudal extent of some MN pools compared with previous reports. The identification of mouse forelimb MNs can serve as an anatomical reference for studying degenerative MN diseases, spinal cord injury, and developmental gene expression.

  9. The magnitude of muscular activation of four canine forelimb muscles in dogs performing two agility-specific tasks.

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    Cullen, Kimberley L; Dickey, James P; Brown, Stephen H M; Nykamp, Stephanie G; Bent, Leah R; Thomason, Jeffrey J; Moens, Noël M M

    2017-03-07

    The purpose of this study was to measure the muscular activation in four forelimb muscles while dogs performed agility tasks (i.e., jumping and A-frame) and to provide insight into potential relationships between level of muscular activation and risk of injury. Muscle activation in eight healthy, client-owned agility dogs was measured using ultrasound-guided fine-wire electromyography of four specific forelimb muscles: Biceps Brachii, Supraspinatus, Infraspinatus, and Triceps Brachii - Long Head, while dogs performed a two jump sequence and while dogs ascended and descended an A-frame obstacle at two different competition heights. The peak muscle activations during these agility tasks were between 1.7 and 10.6 fold greater than walking. Jumping required higher levels of muscle activation compared to ascending and descending an A-frame, for all muscles of interest. There was no significant difference in muscle activation between the two A-frame heights. Compared to walking, all of the muscles were activated at high levels during the agility tasks and our findings indicate that jumping is an especially demanding activity for dogs in agility. This information is broadly relevant to understanding the pathophysiology of forelimb injuries related to canine athletic activity.

  10. Influence of Muscle-Tendon Wrapping on Calculations of Joint Reaction Forces in the Equine Distal Forelimb

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    Jonathan S. Merritt

    2008-01-01

    Full Text Available The equine distal forelimb is a common location of injuries related to mechanical overload. In this study, a two-dimensional model of the musculoskeletal system of the region was developed and applied to kinematic and kinetic data from walking and trotting horses. The forces in major tendons and joint reaction forces were calculated. The components of the joint reaction forces caused by wrapping of tendons around sesamoid bones were found to be of similar magnitude to the reaction forces between the long bones at each joint. This finding highlighted the importance of taking into account muscle-tendon wrapping when evaluating joint loading in the equine distal forelimb.

  11. Development of a subset of forelimb muscles and their attachment sites requires the ulnar-mammary syndrome gene Tbx3

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    Mary P. Colasanto

    2016-11-01

    Full Text Available In the vertebrate limb over 40 muscles are arranged in a precise pattern of attachment via muscle connective tissue and tendon to bone and provide an extensive range of motion. How the development of somite-derived muscle is coordinated with the development of lateral plate-derived muscle connective tissue, tendon and bone to assemble a functional limb musculoskeletal system is a long-standing question. Mutations in the T-box transcription factor, TBX3, have previously been identified as the genetic cause of ulnar-mammary syndrome (UMS, characterized by distinctive defects in posterior forelimb bones. Using conditional mutagenesis in mice, we now show that TBX3 has a broader role in limb musculoskeletal development. TBX3 is not only required for development of posterior forelimb bones (ulna and digits 4 and 5, but also for a subset of posterior muscles (lateral triceps and brachialis and their bone eminence attachment sites. TBX3 specification of origin and insertion sites appears to be tightly linked with whether these particular muscles develop and may represent a newly discovered mechanism for specification of anatomical muscles. Re-examination of an individual with UMS reveals similar previously unrecognized muscle and bone eminence defects and indicates a conserved role for TBX3 in regulating musculoskeletal development.

  12. Passive and active mechanical properties of the superficial and deep digital flexor muscles in the forelimbs of anesthetized Thoroughbred horses.

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    Swanstrom, Michael D; Zarucco, Laura; Stover, Susan M; Hubbard, Mont; Hawkins, David A; Driessen, Bernd; Steffey, Eugene P

    2005-03-01

    The superficial (SDF) and deep digital flexor (DDF) muscles are critical for equine forelimb locomotion. Knowledge of their mechanical properties will enhance our understanding of limb biomechanics. Muscle contractile properties derived from architectural-based algorithms may overestimate real forces and underestimate shortening capacity because of simplistic assumptions regarding muscle architecture. Therefore, passive and active (=total - passive) force-length properties of the SDF and DDF muscles were measured directly in vivo. Muscles from the right forelimbs of four Thoroughbred horses were evaluated during general anesthesia. Limbs were fixed to an external frame with the muscle attached to a linear actuator and load cell. Each muscle was stretched from an unloaded state to a range of prefixed lengths, then stimulated while held at that length. The total force did not exceed 4000 N, the limit for the clamping device. The SDF and DDF muscles produced 716+/-192 and 1577+/-203 N maximum active isometric force (F(max)), had ascending force-length ranges (R(asc)) of 5.1+/-0.2 and 9.1+/-0.4 cm, and had passive stiffnesses of 1186+/-104 and 1132+/-51 N/cm, respectively. The values measured for F(max) were much smaller than predicted based on conservative estimates of muscle specific tension and muscle physiological cross-sectional area. R(asc) were much larger than predicted based on muscle fiber length estimates. These data suggest that accurate prediction of the active mechanical behavior of architecturally complex muscles such as the equine DDF and SDF requires more sophisticated algorithms.

  13. Is salamander limb regeneration really perfect? Anatomical and morphogenetic analysis of forelimb muscle regeneration in GFP-transgenic axolotls as a basis for regenerative, developmental, and evolutionary studies.

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    Diogo, R; Nacu, E; Tanaka, E M

    2014-06-01

    The axolotl Ambystoma mexicanum is one of the most commonly used model organisms in developmental and regenerative studies because it can reconstitute what is believed to be a completely normal anatomical and functional forelimb/hindlimb after amputation. However, to date it has not been confirmed whether each regenerated forelimb muscle is really a "perfect" copy of the original muscle. This study describes the regeneration of the arm, forearm, hand, and some pectoral muscles (e.g., coracoradialis) in transgenic axolotls that express green fluorescent protein (GFP) in muscle fibers. The observations found that: (1) there were muscle anomalies in 43% of the regenerated forelimbs; (2) however, on average in each regenerated forelimb there are anomalies in only 2.5% of the total number of muscles examined, and there were no significant differences observed in the specific insertion and origin of the other muscles analyzed; (3) one of the most notable and common anomalies (seen in 35% of the regenerated forelimbs) was the presence of a fleshy coracoradialis at the level of the arm; this is a particularly outstanding configuration because in axolotls and in urodeles in general this muscle only has a thin tendon at the level of the arm, and the additional fleshy belly in the regenerated arms is strikingly similar to the fleshy biceps brachii of amniotes, suggesting a remarkable parallel between a regeneration defect and a major phenotypic change that occurred during tetrapod limb evolution; (4) during forelimb muscle regeneration there was a clear proximo-distal and radio-ulnar morphogenetic gradient, as seen in normal development, but also a ventro-dorsal gradient in the order of regeneration, which was not previously described in the literature. These results have broader implications for regenerative, evolutionary, developmental and morphogenetic studies. Copyright © 2014 Wiley Periodicals, Inc.

  14. Limitations of surface EMG signals of extrinsic muscles in predicting postures of human hand.

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    Vinjamuri, Ramana; Mao, Zhi-Hong; Sclabassi, Robert; Sun, Mingui

    2006-01-01

    This paper explores the limitations of sEMG (surface Electromyography) signals collected from the extrinsic muscles in the forearm in predicting the postures of human hand. Four subjects were asked to try ten extreme postures of hand which need high effort. Two of these four subjects were asked to try ten more normal postures which did not need effort During the experiments, muscle activity and static postures of the hand were measured. The data obtained were analyzed by principal component analysis. The results obtained revealed the limitations of sEMG signals of extrinsic muscles in reproducing the postures of the hand.

  15. Modified forelimb grip strength test detects aging-associated physiological decline in skeletal muscle function in male mice

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    Takeshita, Hikari; Yamamoto, Koichi; Nozato, Satoko; Inagaki, Tadakatsu; Tsuchimochi, Hirotsugu; Shirai, Mikiyasu; Yamamoto, Ryohei; Imaizumi, Yuki; Hongyo, Kazuhiro; Yokoyama, Serina; Takeda, Masao; Oguro, Ryosuke; Takami, Yoichi; Itoh, Norihisa; Takeya, Yasushi; Sugimoto, Ken; Fukada, So-ichiro; Rakugi, Hiromi

    2017-01-01

    The conventional forelimb grip strength test is a widely used method to assess skeletal muscle function in rodents; in this study, we modified this method to improve its variability and consistency. The modified test had lower variability among trials and days than the conventional test in young C57BL6 mice, especially by improving the variabilities in male. The modified test was more sensitive than the conventional test to detect a difference in motor function between female and male mice, or between young and old male mice. When the modified test was performed on male mice during the aging process, reduction of grip strength manifested between 18 and 24 months of age at the group level and at the individual level. The modified test was similar to the conventional test in detecting skeletal muscle dysfunction in young male dystrophic mice. Thus, the modified forelimb grip strength test, with its improved validity and reliability may be an ideal substitute for the conventional method. PMID:28176863

  16. Muscle architecture of the forelimb of the Golden Pheasant (Chrysolophus pictus) (Aves:Phasianidae) and its implications for functional capacity in flight

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    Yan Yang; Huan Wang; Zihui Zhang

    2015-01-01

    Background:Flight is the central avian adaptation in evolution. Wing muscles form an important anatomical basis for avian flight, affecting wing performance and determine modes of flight. However, the roles of distal muscles in adjusting the wing, as well as their functional specializations, remain largely unknown. The importance of muscle fiber architecture has long been recognized. In this study, we provide quantitative anatomical data on the muscle architecture of the forelimb of the Golden Pheasant (Chrysolophus pictus), with an emphasis on brachial, antebrachial and manual segments. Methods:The forelimbs of five Golden Pheasants were dissected and detailed measurements of all muscles were made, including muscle mass, muscle belly length, fascicle length. From these values, muscle volume, physiological cross-sectional area (PCSA) and maximum isometric force were derived. Results:General trends such as the distribution of muscle mass, fascicle length and the ratio of tendon length/belly length are revealed. Comparing PCSAs between antebrachial depressors and elevators and between intrinsics of the alular digit and major digit yielded significant differences (p Conclusions:These observations illustrate the underlying structural basis for the functional capacities of the distal forelimb muscles and may provide additional information useful in further biomechanical and in vivo investigations.

  17. Effects of testosterone on contractile properties of sexually dimorphic forelimb muscles in male bullfrogs (Rana catesbeiana, Shaw 1802

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    Aaron R. Kampe

    2013-07-01

    This study examined the effects of testosterone (T on the contractile properties of two sexually dimorphic forelimb muscles and one non-dimorphic muscle in male bullfrogs (Rana catesbeiana, Shaw 1802. The dimorphic muscles in castrated males with testosterone replacement (T+ achieved higher forces and lower fatigability than did castrated males without replaced testosterone (T0 males, but the magnitude of the differences was low and many of the pair-wise comparisons of each muscle property were not statistically significant. However, when taken as a whole, the means of seven contractile properties varied in the directions expected of masculine values in T+ animals in the sexually dimorphic muscles. Moreover, these data, compared with previous data on male and female bullfrogs, show that values for T+ males are similar to normal males and are significantly different from females. The T0 males tended to be intermediate in character between T+ males and females, generally retaining masculine values. This suggests that the exposure of young males to T in their first breeding season produces a masculinizing effect on the sexually dimorphic muscles that is not reversed between breeding seasons when T levels are low. The relatively minor differences in contractile properties between T+ and T0 males may indicate that as circulating T levels rise during breeding season in normal males, contractile properties can be enhanced rapidly to maximal functional levels for breeding success.

  18. An Analysis of Intrinsic and Extrinsic Hand Muscle EMG for Improved Pattern Recognition Control.

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    Adewuyi, Adenike A; Hargrove, Levi J; Kuiken, Todd A

    2016-04-01

    Pattern recognition control combined with surface electromyography (EMG) from the extrinsic hand muscles has shown great promise for control of multiple prosthetic functions for transradial amputees. There is, however, a need to adapt this control method when implemented for partial-hand amputees, who possess both a functional wrist and information-rich residual intrinsic hand muscles. We demonstrate that combining EMG data from both intrinsic and extrinsic hand muscles to classify hand grasps and finger motions allows up to 19 classes of hand grasps and individual finger motions to be decoded, with an accuracy of 96% for non-amputees and 85% for partial-hand amputees. We evaluated real-time pattern recognition control of three hand motions in seven different wrist positions. We found that a system trained with both intrinsic and extrinsic muscle EMG data, collected while statically and dynamically varying wrist position increased completion rates from 73% to 96% for partial-hand amputees and from 88% to 100% for non-amputees when compared to a system trained with only extrinsic muscle EMG data collected in a neutral wrist position. Our study shows that incorporating intrinsic muscle EMG data and wrist motion can significantly improve the robustness of pattern recognition control for application to partial-hand prosthetic control.

  19. Coordination of intrinsic and extrinsic hand muscle activity as a function of wrist joint angle during two-digit grasping.

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    Johnston, Jamie A; Bobich, Lisa R; Santello, Marco

    2010-04-26

    Fingertip forces result from the activation of muscles that cross the wrist and muscles whose origins and insertions reside within the hand (extrinsic and intrinsic hand muscles, respectively). Thus, tasks that involve changes in wrist angle affect the moment arm and length, hence the force-producing capabilities, of extrinsic muscles only. If a grasping task requires the exertion of constant fingertip forces, the Central Nervous System (CNS) may respond to changes in wrist angle by modulating the neural drive to extrinsic or intrinsic muscles only or by co-activating both sets of muscles. To distinguish between these scenarios, we recorded electromyographic (EMG) activity of intrinsic and extrinsic muscles of the thumb and index finger as a function of wrist angle during a two-digit object hold task. We hypothesized that changes in wrist angle would elicit EMG amplitude modulation of the extrinsic and intrinsic hand muscles. In one experimental condition we asked subjects to exert the same digit forces at each wrist angle, whereas in a second condition subjects could choose digit forces for holding the object. EMG activity was significantly modulated in both extrinsic and intrinsic muscles as a function of wrist angle (both pmuscles. We conclude that the CNS controlled both extrinsic and intrinsic muscles as a muscle synergy. These findings are discussed within the theoretical frameworks of synergies and common neural input across motor nuclei of hand muscles. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  20. Fiber type distribution in the shoulder muscles of the tree shrew, the cotton-top tamarin, and the squirrel monkey related to shoulder movements and forelimb loading.

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    Schmidt, Manuela; Schilling, Nadja

    2007-04-01

    Muscle fiber type composition of intrinsic shoulder muscles was examined in tree shrews, cotton-top tamarins, and squirrel monkeys with respect to their shoulder kinematics and forelimb loading during locomotion. Enzyme- and immunohistochemical techniques were applied to differentiate muscle fiber types on serial cross-sections of the shoulder. In the majority of the shoulder muscles, the proportions of fatigue resistant slow-twitch fibers (SO) and fatigable fast-twitch fibers (FG) were inversely related to each other, whereas the percentage of intermediate FOG-fibers varied independently. A segregation of fatigue resistant SO-fibers into deep muscle regions is indicative of differential activation of histochemically distinct muscle regions in which deep regions stabilize the joint against gravitational loading. In all three species, this antigravity function was demonstrated for both the supraspinatus and the cranial subscapularis muscle, which prevent passive joint flexion during the support phase of the limb. The infraspinatus muscle showed a high content of SO-fibers in the primate species but not in the tree shrew, which demonstrates the "new" role of the infraspinatus muscle in joint stabilization related to the higher degree of humeral protraction in primates. In the tree shrew and the cotton-top tamarin, a greater proportion of the body weight is carried on the forelimb, but the squirrel monkey exhibits a weight shift to the hind limbs. The lower amount of forelimb loading is reflected by an overall lower proportion of fatigue resistant muscle fibers in the shoulder muscles of the squirrel monkey. Several muscles such as the deltoid no longer function as joint stabilizers and allow the humerus to move beyond the scapular plane. These differences among species demonstrate the high plasticity of the internal muscle architecture and physiology which is suggested to be the underlying reason for different muscle activity patterns in homologous muscles

  1. Modulation of forelimb and hindlimb muscle activity during quadrupedal tied-belt and split-belt locomotion in intact cats.

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    Frigon, A; Thibaudier, Y; Hurteau, M-F

    2015-04-02

    The modulation of the neural output to forelimb and hindlimb muscles when the left and right sides step at different speeds from one another in quadrupeds was assessed by obtaining electromyography (EMG) in seven intact adult cats during split-belt locomotion. To determine if changes in EMG during split-belt locomotion were modulated according to the speed of the belt the limb was stepping on, values were compared to those obtained during tied-belt locomotion (equal left-right speeds) at matched speeds. Cats were chronically implanted for EMG, which was obtained from six muscles: biceps brachii, triceps brachii, flexor carpi ulnaris, sartorius, vastus lateralis and medial gastrocnemius. During tied-belt locomotion, cats stepped from 0.4 to 1.0m/s in 0.1m/s increments whereas during split-belt locomotion, cats stepped with left-right speed differences of 0.1 to 0.4m/s in 0.1m/s increments. During tied-belt locomotion, EMG burst durations and mean EMG amplitudes of all muscles respectively decreased and increased with increasing speed. During split-belt locomotion, there was a clear differential modulation of the EMG patterns between flexors and extensors and between the slow and fast sides. Changes in the EMG pattern of some muscles could be explained by the speed of the belt the limb was stepping on, while in other muscles there were clear dissociations from tied-belt values at matched speeds. Therefore, results show that EMG patterns during split-belt locomotion are modulated to meet task requirements partly via signals related to the stepping speed of the homonymous limb and from the other limbs.

  2. Muscle architecture of the forelimb of the Golden Pheasant(Chrysolophus pictus)(Aves: Phasianidae)and its implications for functional capacity in flight

    Institute of Scientific and Technical Information of China (English)

    Yan; Yang; Huan; Wang; Zihui; Zhang

    2015-01-01

    Background: Flight is the central avian adaptation in evolution. Wing muscles form an important anatomical basis for avian flight, affecting wing performance and determine modes of flight. However, the roles of distal muscles in adjusting the wing, as well as their functional specializations, remain largely unknown. The importance of muscle fiber architecture has long been recognized. In this study, we provide quantitative anatomical data on the muscle architecture of the forelimb of the Golden Pheasant(Chrysolophus pictus), with an emphasis on brachial,antebrachial and manual segments.Methods: The forelimbs of five Golden Pheasants were dissected and detailed measurements of all muscles were made, including muscle mass, muscle belly length, fascicle length. From these values, muscle volume, physiological cross-sectional area(PCSA) and maximum isometric force were derived.Results: General trends such as the distribution of muscle mass, fascicle length and the ratio of tendon length/belly length are revealed. Comparing PCSAs between antebrachial depressors and elevators and between intrinsics of the alular digit and major digit yielded significant differences(p < 0.05). Pronounced development of the antebrachial depressors suggests that ventral rotation of the distal half of the wing is a pivotal factor in shape change and orientation modulation. Large PCSAs in tandem with the force generation capability of the major digit intrinsics may help stabilize the digits while enhancing support of the primary feathers. The architectural properties of the alular digit confirm that alular adjustment is essential to rapid adduction and abduction.Conclusions: These observations illustrate the underlying structural basis for the functional capacities of the distal forelimb muscles and may provide additional information useful in further biomechanical and in vivo investigations.

  3. Electrophysiological and histological changes in extrinsic muscles proximal to post burn contractures of hand.

    Science.gov (United States)

    Bhattacharya, V; Purwar, Shammi; Joshi, D; Kumar, M; Mandal, S; Chaudhuri, G R; Bhattacharya, S

    2011-06-01

    Burn scar hand contractures of variable degree are frequently encountered. Although the forearm is apparently spared, it was clinically observed that there was disuse atrophy in the unburnt extrinsic forearm muscles. Usually the clinicians do not give much importance to this fact. The girth at the midforearm was significantly reduced as compared to normal side. The flexion of the hand joints are governed by two components (a) intrinsic and (b) extrinsic muscles. The intrinsic muscles are directly involved in the contracted tissue. Therefore it was thought essential to evaluate the extrinsic group of muscles for their contribution in the final functional recovery following corrective surgery. Thirty patients having unilateral post thermal burn contracture sparing forearm were studied. A detailed clinical evaluation was made including grade of contracture and reduction in the forearm girth. The forearm unburnt muscles were evaluated by preoperative electrophysiological studies. Intraoperative biopsies were taken from these muscles for histopathological examination. On histopathological examination, there were significant abnormal changes in the form of muscle fiber atrophy, fibrolipomatous tissue replacement of atrophic muscle fibers and sarcolemmal changes. These changes were directly proportional to the severity of contractures. The electrophysiological studies showed proportionate changes in the form of reduction in amplitude, duration and interference. This study suggests that if these changes are mild and in reversible stage, they will favourably affect the functional recovery following surgery. However if these changes are of severe grade and irreversible, in spite of adequate surgery, splinting and physiotherapy, the functional recovery may not be complete. Copyright © 2011 Elsevier Ltd and ISBI. All rights reserved.

  4. Finger joint motion generated by individual extrinsic muscles: A cadaveric study

    Directory of Open Access Journals (Sweden)

    Li Zong-Ming

    2008-07-01

    Full Text Available Abstract Background Our understanding of finger functionality associated with the specific muscle is mostly based on the functional anatomy, and the exact motion effect associated with an individual muscle is still unknown. The purpose of this study was to examine phalangeal joints motion of the index finger generated by each extrinsic muscle. Methods Ten (6 female and 4 male fresh-frozen cadaveric hands (age 55.2 ± 5.6 years were minimally dissected to establish baseball sutures at the musculotendinous junctions of the index finger extrinsic muscles. Each tendon was loaded to 10% of its force potential and the motion generated at the metacarpophalangeal (MCP, proximal interphalangeal (PIP, and distal interphalangeal (DIP joints was simultaneously recorded using a marker-based motion capture system. Results The flexor digitorum profundus (FDP generated average flexion of 19.7, 41.8, and 29.4 degrees at the MCP, PIP, and DIP joints, respectively. The flexor digitorum superficialis (FDS generated average flexion of 24.8 and 47.9 degrees at the MCP and PIP joints, respectively, and no motion at the DIP joints. The extensor digitorum communis (EDC and extensor indicis proprius (EIP generated average extension of 18.3, 15.2, 4.0 degrees and 15.4, 13.2, 3.7 degrees at the MCP, PIP and DIP joints, respectively. The FDP generated simultaneous motion at the PIP and DIP joints. However, the motion generated by the FDP and FDS, at the MCP joint lagged the motion generated at the PIP joint. The EDC and EIP generated simultaneous motion at the MCP and PIP joints. Conclusion The results of this study provide novel insights into the kinematic role of individual extrinsic muscles.

  5. Molecular signatures of amyotrophic lateral sclerosis disease progression in hind and forelimb muscles of an SOD1(G93A) mouse model.

    Science.gov (United States)

    Capitanio, Daniele; Vasso, Michele; Ratti, Antonia; Grignaschi, Giuliano; Volta, Manuela; Moriggi, Manuela; Daleno, Cristina; Bendotti, Caterina; Silani, Vincenzo; Gelfi, Cecilia

    2012-11-15

    This study utilized proteomics, biochemical and enzymatic assays, and bioinformatics tools that characterize protein alterations in hindlimb (gastrocnemius) and forelimb (triceps) muscles in an amyotrophic lateral sclerosis (ALS) (SOD1(G93A)) mouse model. The aim of this study was to identify the key molecular signatures involved in disease progression. Both muscle types have in common an early down-regulation of complex I. In the hindlimb, early increases in oxidative metabolism are associated with uncoupling of the respiratory chain, an imbalance of NADH/NAD(+), and an increase in reactive oxygen species (ROS) production. The NADH overflow due to complex I inactivation induces TCA flux perturbations, leading to citrate production, triggering fatty acid synthase (FAS), and lipid peroxidation. These early metabolic changes in the hindlimb followed by sustained and comparatively higher metabolic and cytoskeletal derangements over time precede and may catalyze the progressive muscle wasting in this muscle at the late stage. By contrast, in the forelimb, there is an early down-regulation of complexes I and II that is associated with the reduction of oxidative metabolism, which promotes metabolic homeostasis that is accompanied by a greater cytoskeletal stabilization response. However, these early compensatory systems diminish by a later time point. The identification of potential early- and late-stage disease molecular signatures in an ALS model: muscle albumin, complex I, complex II, citrate synthase, FAS, and phosphoinositide 3-kinase functions as diagnostic markers and peroxisome proliferator-activated receptor γ co-activator 1α (PGC1α), Sema-3A, and Rho-associated protein kinase 1 (ROCK1) play the role of disease progression markers. The differing pattern of cellular metabolism and cytoskeletal derangements in the hind and forelimb identifies the potential dysmetabolism/hypermetabolism molecular signatures associated with disease progression, which may serve as

  6. Common input to motor units of intrinsic and extrinsic hand muscles during two-digit object hold.

    Science.gov (United States)

    Winges, Sara A; Kornatz, Kurt W; Santello, Marco

    2008-03-01

    Anatomical and physiological evidence suggests that common input to motor neurons of hand muscles is an important neural mechanism for hand control. To gain insight into the synaptic input underlying the coordination of hand muscles, significant effort has been devoted to describing the distribution of common input across motor units of extrinsic muscles. Much less is known, however, about the distribution of common input to motor units belonging to different intrinsic muscles and to intrinsic-extrinsic muscle pairs. To address this void in the literature, we quantified the incidence and strength of near-simultaneous discharges of motor units residing in either the same or different intrinsic hand muscles (m. first dorsal, FDI, and m. first palmar interosseus, FPI) during two-digit object hold. To extend the characterization of common input to pairs of extrinsic muscles (previous work) and pairs of intrinsic muscles (present work), we also recorded electromyographic (EMG) activity from an extrinsic thumb muscle (m. flexor pollicis longus, FPL). Motor-unit synchrony across FDI and FPI was weak (common input strength, CIS, mean +/- SE: 0.17 +/- 0.02). Similarly, motor units from extrinsic-intrinsic muscle pairs were characterized by weak synchrony (FPL-FDI: 0.25 +/- 0.02; FPL-FPI: 0.29 +/- 0.03) although stronger than FDI-FPI. Last, CIS from within FDI and FPI was more than three times stronger (0.70 +/- 0.06 and 0.66 +/- 0.06, respectively) than across these muscles. We discuss present and previous findings within the framework of muscle-pair specific distribution of common input to hand muscles based on their functional role in grasping.

  7. Is salamander hindlimb regeneration similar to that of the forelimb? Anatomical and morphogenetic analysis of hindlimb muscle regeneration in GFP-transgenic axolotls as a basis for regenerative and developmental studies

    Science.gov (United States)

    Diogo, R; Murawala, P; Tanaka, E M

    2014-01-01

    The axolotl Ambystoma mexicanum is one of the most used model organisms in developmental and regenerative studies because it is commonly said that it can reconstitute a normal and fully functional forelimb/hindlimb after amputation. However, there is not a publication that has described in detail the regeneration of the axolotl hindlimb muscles. Here we describe and illustrate, for the first time, the regeneration of the thigh, leg and foot muscles in transgenic axolotls that express green fluorescent protein in muscle fibers and compare our results with data obtained by us and by other authors about axolotl forelimb regeneration and about fore-and hindlimb ontogeny in axolotls, frogs and other tetrapods. Our observations and comparisons point out that: (1) there are no muscle anomalies in any regenerated axolotl hindlimbs, in clear contrast to our previous study of axolotl forelimb regeneration, where we found muscle anomalies in 43% of the regenerated forelimbs; (2) during axolotl hindlimb regeneration there is a proximo-distal and a tibio-fibular morphogenetic gradient in the order of muscle regeneration and differentiation, but not a ventro-dorsal gradient, whereas our previous studies showed that in axolotl forelimb muscle regeneration there are proximo-distal, radio-ulnar and ventro-dorsal morphogenetic gradients. We discuss the broader implications of these observations for regenerative, evolutionary, developmental and morphogenetic studies. PMID:24325444

  8. Is salamander hindlimb regeneration similar to that of the forelimb? Anatomical and morphogenetic analysis of hindlimb muscle regeneration in GFP-transgenic axolotls as a basis for regenerative and developmental studies.

    Science.gov (United States)

    Diogo, R; Murawala, P; Tanaka, E M

    2014-04-01

    The axolotl Ambystoma mexicanum is one of the most used model organisms in developmental and regenerative studies because it is commonly said that it can reconstitute a normal and fully functional forelimb/hindlimb after amputation. However, there is not a publication that has described in detail the regeneration of the axolotl hindlimb muscles. Here we describe and illustrate, for the first time, the regeneration of the thigh, leg and foot muscles in transgenic axolotls that express green fluorescent protein in muscle fibers and compare our results with data obtained by us and by other authors about axolotl forelimb regeneration and about fore- and hindlimb ontogeny in axolotls, frogs and other tetrapods. Our observations and comparisons point out that: (1) there are no muscle anomalies in any regenerated axolotl hindlimbs, in clear contrast to our previous study of axolotl forelimb regeneration, where we found muscle anomalies in 43% of the regenerated forelimbs; (2) during axolotl hindlimb regeneration there is a proximo-distal and a tibio-fibular morphogenetic gradient in the order of muscle regeneration and differentiation, but not a ventro-dorsal gradient, whereas our previous studies showed that in axolotl forelimb muscle regeneration there are proximo-distal, radio-ulnar and ventro-dorsal morphogenetic gradients. We discuss the broader implications of these observations for regenerative, evolutionary, developmental and morphogenetic studies. © 2013 Anatomical Society.

  9. Periodic Modulation of Motor-Unit Activity in Extrinsic Hand Muscles During Multidigit Grasping

    Science.gov (United States)

    Johnston, Jamie A.; Winges, Sara A.; Santello, Marco

    2007-01-01

    We recently examined the extent to which motor units of digit flexor muscles receive common input during multidigit grasping. This task elicited moderate to strong motor-unit synchrony (common input strength, CIS) across muscles (flexor digitorum profundus, FDP, and flexor pollicis longus, FPL) and across FDP muscle compartments, although the strength of this common input was not uniform across digit pairs. To further characterize the neural mechanisms underlying the control of multidigit grasping, we analyzed the relationship between firing of single motor units from these hand muscles in the frequency domain by computing coherence. We report three primary findings. First, in contrast to what has been reported in intrinsic hand muscles, motor units belonging to different muscles and muscle compartments of extrinsic digit flexors exhibited significant coherence in the 0- to 5- and 5- to 10-Hz frequency ranges and much weaker coherence in the higher 10–20 Hz range (maximum 0.0025 and 0.0008, respectively, pooled across all FDP compartment pairs). Second, the strength and incidence of coherence differed considerably across digit pairs. Third, contrary to what has been reported in the literature, across-muscle coherence can be stronger and more prevalent than within-muscle coherence, as FPL–FDP2 (thumb-index digit pair) exhibited the strongest and most prevalent coherence in our data (0.010 and 43% at 3 Hz, respectively). The heterogeneous organization of common input to these muscles and muscle compartments is discussed in relation to the functional role of individual digit pairs in the coordination of multiple digit forces in grasping. PMID:15744006

  10. Direct muscle neurotization after end-to end and end-to-side neurorrhaphy: An experimental study in the rat forelimb model.

    Science.gov (United States)

    Papalia, Igor; Ronchi, Giulia; Muratori, Luisa; Mazzucco, Alessandra; Magaudda, Ludovico; Geuna, Stefano

    2012-10-15

    The need for the continuous research of new tools for improving motor function recovery after nerve injury is justified by the still often unsatisfactory clinical outcome in these patients. It has been previously shown that the combined use of two reconstructive techniques, namely end-to-side neurorrhaphy and direct muscle neurotization in the rat hindlimb model, can lead to good results in terms of skeletal muscle reinnervation. Here we show that, in the rat forelimb model, the combined use of direct muscle neurotization with either end-to-end or end-to-side neurorrhaphy to reinnervate the denervated flexor digitorum muscles, leads to muscle atrophy prevention over a long postoperative time lapse (10 months). By contrast, very little motor recovery (in case of end-to-end neurorrhaphy) and almost no motor recovery (in case of end-to-side neurorrhaphy) were observed in the grasping activity controlled by flexor digitorum muscles. It can thus be concluded that, at least in the rat, direct muscle neurotization after both end-to-end and end-to-side neurorrhaphy represents a good strategy for preventing denervation-related muscle atrophy but not for regaining the lost motor function.

  11. Direct muscle neurotization after end-to-end and end-to-side neurorrhaphy An experimental study in the rat forelimb model

    Institute of Scientific and Technical Information of China (English)

    Igor Papalia; Giulia Ronchi; Luisa Muratori; Alessandra Mazzucco; Ludovico Magaudda; Stefano Geuna

    2012-01-01

    The need for the continuous research of new tools for improving motor function recovery after nerve injury is justified by the still often unsatisfactory clinical outcome in these patients.It has been previously shown that the combined use of two reconstructive techniques,namely end-to-side neurorrhaphy and direct muscle neurotization in the rat hindlimb model,can lead to good results in terms of skeletal muscle reinnervation.Here we show that,in the rat forelimb model,the combined use of direct muscle neurotization with either end-to-end or end-to-side neurorrhaphy to reinnervate the denervated flexor digitorum muscles,leads to muscle atrophy prevention over a long postoperative time lapse (10 months).By contrast,very little motor recovery (in case of end-to-end neurorrhaphy) and almost no motor recovery (in case of end-to-side neurorrhaphy) were observed in the grasping activity controlled by flexor digitorum muscles.It can thus be concluded that,at least in the rat,direct muscle neurotization after both end-to-end and end-to-side neurorrhaphy represents a good strategy for preventing denervation-related muscle atrophy but not for regaining the lost motor function.

  12. Extrinsic finger and thumb muscles command a virtual hand to allow individual finger and grasp control.

    Science.gov (United States)

    Birdwell, J Alexander; Hargrove, Levi J; Weir, Richard F ff; Kuiken, Todd A

    2015-01-01

    Fine-wire intramuscular electrodes were used to obtain electromyogram (EMG) signals from six extrinsic hand muscles associated with the thumb, index, and middle fingers. Subjects' EMG activity was used to control a virtual three-degree-of-freedom (DOF) hand as they conformed the hand to a sequence of hand postures testing two controllers: direct EMG control and pattern recognition control. Subjects tested two conditions using each controller: starting the hand from a predefined neutral posture before each new posture and starting the hand from the previous posture in the sequence. Subjects demonstrated their abilities to simultaneously, yet individually, move all three DOFs during the direct EMG control trials; however, results showed subjects did not often utilize this feature. Performance metrics such as failure rate and completion time showed no significant difference between the two controllers.

  13. Motor cortical plasticity in extrinsic hand muscles is determined by the resting thresholds of overlapping representations.

    Science.gov (United States)

    Mirdamadi, J L; Suzuki, L Y; Meehan, S K

    2016-10-01

    Knowledge of the properties that govern the effectiveness of transcranial magnetic stimulation (TMS) interventions is critical to clinical application. Extrapolation to clinical populations has been limited by high inter-subject variability and a focus on intrinsic muscles of the hand in healthy populations. Therefore, the current study assessed variability of continuous theta burst stimulation (cTBS), a patterned TMS protocol, across an agonist-antagonist pair of extrinsic muscles of the hand. Secondarily, we assessed whether concurrent agonist contraction could enhance the efficacy of cTBS. Motor evoked potentials (MEP) were simultaneously recorded from the agonist flexor (FCR) and antagonist extensor (ECR) carpi radialis before and after cTBS over the FCR hotspot. cTBS was delivered with the FCR relaxed (cTBS-Relax) or during isometric wrist flexion (cTBS-Contract). cTBS-Relax suppressed FCR MEPs evoked from the FCR hotspot. However, the extent of FCR MEP suppression was strongly correlated with the relative difference between FCR and ECR resting motor thresholds. cTBS-Contract decreased FCR suppression but increased suppression of ECR MEPs elicited from the FCR hotspot. The magnitude of ECR MEP suppression following cTBS-Contract was independent of the threshold-amplitude relationships observed with cTBS-Relax. Contraction alone had no effect confirming the effect of cTBS-Contract was driven by the interaction between neuromuscular activity and cTBS. Interactions across muscle representations should be taken into account when predicting cTBS outcomes in healthy and clinical populations. Contraction during cTBS may be a useful means of focusing aftereffects when differences in baseline excitability across overlapping agonist-antagonist cortical representations may mitigate the inhibitory effect of cTBS. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  14. Biochemical organization of single motor units in two multi-tendoned muscles of the cat distal forelimb.

    Science.gov (United States)

    Fritz, N; Schmidt, C; Yamaguchi, T

    1992-01-01

    In anesthetized cats single motor units (MUs) of the extensor carpi ulnaris (ECU) and extensor digitorum communis (EDC) muscles were selectively activated by stimulation of cervical ventral root filaments. The distribution of force developed by single MUs at the four distal tendons of the EDC muscle and at three portions of the distal tendon of the ECU muscle was analysed. In general, single MUs of both muscles distributed force over all tendons in a unimodal pattern, with the maximal force levels generated at one specific tendon which was termed the best-tendon. Distributions of force were quantitatively described by a parameter representing the mean direction of force output (output-index) and a further one representing the dispersion of force over the distal tendons (divergence). Generally, these parameters and the best-tendon remained stable when a MU was stimulated at different frequencies, but varied from MU to MU. Despite the general stability of the force distribution, slight systematic changes were regularly found in EDC MUs, when they developed a higher amount of force due to a higher frequency of stimulation: the relative amount of force at the best-tendon increased; e.g. the MUs got more selective for the best-tendon. These changes were partly due to overcoming mechanical cross-coupling between neighbouring compartments of the EDC muscle. Such changes of force distribution were only found in a part of the ECU MUs; other ECU MUs did not change their force distribution at all or became less selective for the best-tendon. The phenomenon that MUs of multi-tendoned muscles distribute their force output to the distal tendons in specific patterns is probably due to mechanical partitioning of the parent muscles: the localization of spatial territories of MUs within different anatomical muscle compartments should correspond to the best-tendon. Complex mechanisms allowing passive transmission of force from limited territories along the transverse axis of both

  15. Effects of reinnervation of the biarticular shoulder-elbow muscles on joint kinematics and electromyographic patterns of the feline forelimb during downslope walking.

    Science.gov (United States)

    Livingston, Beven P; Nichols, T Richard

    2014-01-01

    Full recovery of the forelimb kinematics during level and upslope walking following reinnervation of the biarticular elbow extensor suggests that the proprioceptive loss is compensated by other sensory sources or altered central drive, yet these findings have not been explored in downslope walking. Kinematics and muscle activity of the shoulder and elbow during downslope locomotion following reinnervation of the feline long head of the triceps brachii (TLo) and biceps brachii (Bi) were evaluated (1) during paralysis and (2) after the motor function was recovered but the proprioceptive feedback was permanently disrupted. The step cycle was examined in three walking conditions: level (0%), -25% grade (-14° downslope) and -50% grade (-26.6° downslope). Measurements were taken prior to and at three time points (2 weeks, and 1 and 12+ months) after transecting and suturing the radial and musculocutaneous nerves. There was an increase in the yield (increased flexion) at the elbow and less extensor activity duration of flexion during stance as the downslope grade increased. There were two notable periods of eccentric contractions (active lengthening) providing an apparent 'braking' action. Paralysis of the TLo and the Bi resulted in uncompensated alterations in shoulder-elbow kinematics and motor activity during the stance phase. However, unlike the case for the level and upslope conditions, during both paralysis and reinnervation, changes in interjoint coordination persisted for the downslope condition. The lack of complete recovery in the long term suggests that the autogenic reflexes contribute importantly to muscle and joint stiffness during active lengthening. © 2015 S. Karger AG, Basel.

  16. Characteristics of leading forelimb movements for obstacle avoidance during locomotion in rats.

    Science.gov (United States)

    Aoki, Sho; Sato, Yamato; Yanagihara, Dai

    2012-10-01

    Walking smoothly and safely often involves stepping over an obstacle. The purpose of this study was to examine forelimb movements and toe trajectories in stepping over an obstacle during overground locomotion in rats. We performed a kinematic analysis of forelimb movements and measured electromyographic (EMG) activities in the biceps and triceps brachii of the forelimbs. We found that mean toe height just above the obstacle was lower in the leading forelimb than in the trailing forelimb. The toe positions of the leading forelimb at maximal elevation over the obstacle (peak toe position) were closer to the upper edge of the obstacle than those of the trailing forelimb. The linear distance between peak toe position and the upper edge of the obstacle was significantly less in the leading forelimb compared to the trailing forelimb. The peak toe position of the leading forelimb spatially corresponds to the transition point from flexion to extension of the elbow joint. This transition appeared to be controlled mainly by an offset of EMG activity of the elbow flexor, the biceps brachii muscle. In contrast, the trailing forelimb appeared to be controlled by the shoulder and wrist joints. These results suggest that the toe trajectory of the leading forelimb is more accurately regulated than that of the trailing forelimb. In addition, the activities of the elbow flexor may in part contribute to the toe trajectory of the leading forelimb. Copyright © 2012 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

  17. Muscle-Pair Specific Distribution and Grip-Type Modulation of Neural Common Input to Extrinsic Digit Flexors

    Science.gov (United States)

    Winges, Sara A.; Johnston, Jamie A.; Santello, Marco

    2007-01-01

    To gain insight into the synergistic control of hand muscles, we have recently quantified the strength of correlated neural activity across motor units from extrinsic digit flexors during a five-digit object-hold task. We found stronger synchrony and coherence across motor units from thumb and index finger flexor muscle compartment than between the thumb flexor and other finger flexor muscle compartments. The present study of two-digit object hold was designed to determine the extent to which such distribution of common input among thumb-finger flexor muscle compartments, revealed by holding an object with five digits, is preserved when varying the functional role of a given digit pair. We recorded normal force exerted by the digits and electrical activity of single motor units from muscle flexor pollicis longus (FPL) and two compartments of the m. flexor digitorum profundus (FDP2 and FDP3; index and middle finger, respectively). Consistent with our previous results from five-digit grasping, synchrony and coherence across motor units from FPL-FDP2 was significantly stronger than in FPL-FDP3 during object hold with two digits [common input strength: 0.49 ± 0.02 and 0.35 ± 0.02 (means ± SE), respectively; peak coherence: 0.0054 and 0.0038, respectively]. This suggests that the distribution of common neural input is muscle-pair specific regardless of grip type. However, the strength of coherence, but not synchrony, was significantly stronger in two- versus five-digit object hold for both muscle combinations, suggesting the periodicity of common input is sensitive to grip type. PMID:16723414

  18. Joint work and power for both the forelimb and hindlimb during trotting in the horse.

    Science.gov (United States)

    Dutto, Darren J; Hoyt, Donald F; Clayton, Hilary M; Cogger, Edward A; Wickler, Steven J

    2006-10-01

    The net work of the limbs during constant speed over level ground should be zero. However, the partitioning of negative and positive work between the fore- and hindlimbs of a quadruped is not likely to be equal because the forelimb produces a net braking force while the hindlimb produces a net propulsive force. It was hypothesized that the forelimb would do net negative work while the hindlimb did net positive work during trotting in the horse. Because vertical and horizontal impulses remain unchanged across speeds it was hypothesized that net work of both limbs would be independent of speed. Additionally because the major mass of limb musculature is located proximally, it was hypothesized that proximal joints would do more work than distal joints. Kinetic and kinematic analysis were combined using inverse dynamics to calculate work and power for each joint of horses trotting at between 2.5 and 5.0 m s(-1). Work done by the hindlimb was indeed positive (consistently 0.34 J kg(-1) across all speeds), but, contrary to our hypothesis, net work by the forelimb was essentially zero (but also independent of trotting speed). The zero net work of the forelimb may be the consequence of our not being able to account, experimentally, for the negative work done by the extrinsic muscles connecting the scapula and the thorax. The distal three joints of both limbs behaved elastically with a period of energy absorption followed by energy return. Proximal forelimb joints (elbow and shoulder) did no net work, because there was very little movement of the elbow and shoulder during the portion of stance when an extensor moment was greatest. Of the two proximal hindlimb joints, the hip did positive work during the stride, generating energy almost throughout stance. The knee did some work, but like the forelimb proximal joints, had little movement during the middle of stance when the flexion moment was the greatest, probably serving to allow the efficient transmission of energy from the

  19. Anatomy of the pectoral and forelimb muscles of wildtype and green fluorescent protein-transgenic axolotls and comparison with other tetrapods including humans: a basis for regenerative, evolutionary and developmental studies

    Science.gov (United States)

    Diogo, R; Tanaka, E M

    2012-01-01

    The axolotl Ambystoma mexicanum is one of the most used model organisms in evolutionary, developmental and regenerative studies, particularly because it can reconstitute a fully functional and complete forelimb/hindlimb. Surprisingly, there is no publication that describes all the pectoral and forelimb muscles of this species or provides a comparative framework between these muscles and those of other model organisms and of modern humans. In the present paper we describe and illustrate all these muscles in A. mexicanum and provide the first report about the myology of adults of a model organism that is based on analyses and dissections of both wildtype animals and transgenic animals that express green fluorescent protein (GFP) in muscle fibers. On the one hand, the inclusion of GFP-transgenic animals allows us to show the muscles as more commonly seen, and thus easier to understand, by current developmental and regenerative biologists. On the other hand, by including wildtype and GFP-transgenic animals and by visualizing these latter animals with and without a simultaneous transmission laser light, we were able to obtain a more complete and clearer understanding of the exact limit of the fleshy and tendinous parts of the muscles and their specific connections with the skeletal elements. This in turn allowed us to settle some controversies in previous anatomical and comparative studies. As most developmental, regenerative and evolutionary biologists are interested in comparing their observations of A. mexicanum with observations in other model organisms, and ultimately in using this information to increase the understanding of human evolution and medicine, we also provide tables showing the homologies between the pectoral and forelimb muscles of axolotls, of model organisms such as mice, frogs and chicken, and of Homo sapiens. An example illustrating the outcomes of using our methodology and of our observations is that they revealed that, contrary to what is often

  20. Anatomy of the pectoral and forelimb muscles of wildtype and green fluorescent protein-transgenic axolotls and comparison with other tetrapods including humans: a basis for regenerative, evolutionary and developmental studies.

    Science.gov (United States)

    Diogo, R; Tanaka, E M

    2012-12-01

    The axolotl Ambystoma mexicanum is one of the most used model organisms in evolutionary, developmental and regenerative studies, particularly because it can reconstitute a fully functional and complete forelimb/hindlimb. Surprisingly, there is no publication that describes all the pectoral and forelimb muscles of this species or provides a comparative framework between these muscles and those of other model organisms and of modern humans. In the present paper we describe and illustrate all these muscles in A. mexicanum and provide the first report about the myology of adults of a model organism that is based on analyses and dissections of both wildtype animals and transgenic animals that express green fluorescent protein (GFP) in muscle fibers. On the one hand, the inclusion of GFP-transgenic animals allows us to show the muscles as more commonly seen, and thus easier to understand, by current developmental and regenerative biologists. On the other hand, by including wildtype and GFP-transgenic animals and by visualizing these latter animals with and without a simultaneous transmission laser light, we were able to obtain a more complete and clearer understanding of the exact limit of the fleshy and tendinous parts of the muscles and their specific connections with the skeletal elements. This in turn allowed us to settle some controversies in previous anatomical and comparative studies. As most developmental, regenerative and evolutionary biologists are interested in comparing their observations of A. mexicanum with observations in other model organisms, and ultimately in using this information to increase the understanding of human evolution and medicine, we also provide tables showing the homologies between the pectoral and forelimb muscles of axolotls, of model organisms such as mice, frogs and chicken, and of Homo sapiens. An example illustrating the outcomes of using our methodology and of our observations is that they revealed that, contrary to what is often

  1. Smooth muscle cell-extrinsic vascular spasm arises from cardiomyocyte degeneration in sarcoglycan-deficient cardiomyopathy.

    Science.gov (United States)

    Wheeler, Matthew T; Allikian, Michael J; Heydemann, Ahlke; Hadhazy, Michele; Zarnegar, Sara; McNally, Elizabeth M

    2004-03-01

    Vascular spasm is a poorly understood but critical biomedical process because it can acutely reduce blood supply and tissue oxygenation. Cardiomyopathy in mice lacking gamma-sarcoglycan or delta-sarcoglycan is characterized by focal damage. In the heart, sarcoglycan gene mutations produce regional defects in membrane permeability and focal degeneration, and it was hypothesized that vascular spasm was responsible for this focal necrosis. Supporting this notion, vascular spasm was noted in coronary arteries, and disruption of the sarcoglycan complex was observed in vascular smooth muscle providing a molecular mechanism for spasm. Using a transgene rescue strategy in the background of sarcoglycan-null mice, we replaced cardiomyocyte sarcoglycan expression. Cardiomyocyte-specific sarcoglycan expression was sufficient to correct cardiac focal degeneration. Intriguingly, successful restoration of the cardiomyocyte sarcoglycan complex also eliminated coronary artery vascular spasm, while restoration of smooth muscle sarcoglycan in the background of sarcoglycan-null alleles did not. This mechanism, whereby tissue damage leads to vascular spasm, can be partially corrected by NO synthase inhibitors. Therefore, we propose that cytokine release from damaged cardiomyocytes can feed back to produce vascular spasm. Moreover, vascular spasm feeds forward to produce additional cardiac damage.

  2. Dexterous control of a prosthetic hand using fine-wire intramuscular electrodes in targeted extrinsic muscles.

    Science.gov (United States)

    Cipriani, Christian; Segil, Jacob L; Birdwell, J Alex; ff Weir, Richard F

    2014-07-01

    Restoring dexterous motor function equivalent to that of the human hand after amputation is one of the major goals in rehabilitation engineering. To achieve this requires the implementation of a effortless human-machine interface that bridges the artificial hand to the sources of volition. Attempts to tap into the neural signals and to use them as control inputs for neuroprostheses range in invasiveness and hierarchical location in the neuromuscular system. Nevertheless today, the primary clinically viable control technique is the electromyogram measured peripherally by surface electrodes. This approach is neither physiologically appropriate nor dexterous because arbitrary finger movements or hand postures cannot be obtained. Here we demonstrate the feasibility of achieving real-time, continuous and simultaneous control of a multi-digit prosthesis directly from forearm muscles signals using intramuscular electrodes on healthy subjects. Subjects contracted physiologically appropriate muscles to control four degrees of freedom of the fingers of a physical robotic hand independently. Subjects described the control as intuitive and showed the ability to drive the hand into 12 postures without explicit training. This is the first study in which peripheral neural correlates were processed in real-time and used to control multiple digits of a physical hand simultaneously in an intuitive and direct way.

  3. Different cerebral plasticity of intrinsic and extrinsic hand muscles after peripheral neurotization in a patient with brachial plexus injury: A TMS and fMRI study.

    Science.gov (United States)

    Li, Tie; Hua, Xu-Yun; Zheng, Mou-Xiong; Wang, Wei-Wei; Xu, Jian-Guang; Gu, Yu-Dong; Xu, Wen-Dong

    2015-09-14

    Contralateral C7 (CC7) neurotization has been an important approach for brachial plexus injury (BPI). Patients can achieve relatively good grasping function driven by the proximal extrinsic hand muscle (flexor digitorum, FD) after CC7 neurotization, whereas the thumb opposition function driven by the distal intrinsic muscle (abductor pollicis brevis, APB) is poor. The present study aimed to investigate the brain reorganization patterns of the recovery processes of intrinsic and extrinsic hand functions after repairing the median nerve by CC7 neurotization. Transcranial magnetic stimulation (TMS) and functional magnetic resonance imaging (fMRI) were used to evaluate the cerebral plasticity in one BPI patient after CC7 neurotization. After the CC7 neurotization, the patient showed improvements in the paralyzed hand. Combination of TMS and fMRI investigations demonstrated different cortical reshaping patterns of APB and FD. It was also found that the activated cortical areas of FD were located in bilateral motor cortices, but the area of APB was only located in ipsilateral motor cortex. The cerebral plasticity procedure appeared to be different in the gross and fine motor function recovery processes. It provided a new perspective into the cerebral plasticity induced by CC7 neurotization. Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  4. Myology of the forelimb of Majungasaurus crenatissimus (Theropoda, Abelisauridae) and the morphological consequences of extreme limb reduction.

    Science.gov (United States)

    Burch, Sara H

    2017-08-01

    Forelimb reduction occurred independently in multiple lineages of theropod dinosaurs. Although tyrannosaurs are renowned for their tiny, two-fingered forelimbs, the degree of their reduction in length is surpassed by abelisaurids, which possess an unusual morphology distinct from that of other theropods. The forelimbs of abelisaurids are short but robust and exhibit numerous crests, tubercles, and scars that allow for inferences of muscle attachment sites. Phylogenetically based reconstructions of the musculature were used in combination with close examination of the osteology in the Malagasy abelisaurid Majungasaurus to create detailed muscle maps of the forelimbs, and patterns of the muscular and bony morphology were compared with those of extant tetrapods with reduced or vestigial limbs. The lever arms of muscles crossing the glenohumeral joint are shortened relative to the basal condition, reducing the torque of these muscles but increasing the excursion of the humerus. Fusion of the antebrachial muscles into a set of flexors and extensors is common in other tetrapods and occurred to some extent in Majungasaurus. However, the presence of tubercles on the antebrachial and manual elements of abelisaurids indicates that many of the individual distal muscles acting on the wrist and digits were retained. Majungasaurus shows some signs of the advanced stages of forelimb reduction preceding limb loss, while also exhibiting features suggesting that the forelimb was not completely functionless. The conformation of abelisaurid forelimb musculature was unique among theropods and further emphasizes the unusual morphology of the forelimbs in this clade. © 2017 Anatomical Society.

  5. MACROSCOPIC ANATOMY OF THE FORELIMB MUSCULATURE IN THE WHITE FRONTED CAPUCHIN MONKEY (CEBUS ALBIFRONS)

    OpenAIRE

    Cribillero Ch., Nelly; Laboratorio de Anatomía Animal y Fauna Silvestre, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima; Sato S., Alberto; Laboratorio de Anatomía Animal y Fauna Silvestre, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima; Navarrete Z., Miluska; Laboratorio de Anatomía Animal y Fauna Silvestre, Laboratorio de Patología Clínica y Biología Molecular, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima, Perú.

    2012-01-01

    The objective of the present study was to identify and describe the muscular structures of the forelimb of the white fronted capuchin (Cebus albifrons). Four male adult specimens were used. The standard techniques for embalming were used and the dissection of the muscles was made in the lateral and medial side of the forelimb. It is described 42 muscles, of which six muscles were in the shoulder girdle, six muscles in the region of the upper arm, 19 muscles in the region of the forearm where ...

  6. Nomenclatural review of long digital forelimb flexors in carnivores.

    Science.gov (United States)

    Spoor, C F; Badoux, D M

    1986-12-01

    A hitherto-unknown atavistic muscle in the dog initiated a review of the literature on the homologies and nomenclature of the forelimb flexors in carnivores and man. A consequence is that we recommend a revision of the nomenclature in the Nomina Anatomica Veterinaria (Ithaca, New York, 1983) so that it is in agreement with the Nomina Anatomica (Wilkins, Baltimore, 1983). This revision mainly consists of the incorporation of the terms M. palmaris longus and Mm. flexores breves manus.

  7. Contribution of the forelimbs and hindlimbs of the horse to mechanical energy changes in jumping.

    Science.gov (United States)

    Bobbert, Maarten F; Santamaría, Susana

    2005-01-01

    The purpose of the present study was to gain more insight into the contribution of the forelimbs and hindlimbs of the horse to energy changes during the push-off for a jump. For this purpose, we collected kinematic data at 240 Hz from 23 5-year-old Warmbloods (average mass: 595 kg) performing free jumps over a 1.15 m high fence. From these data, we calculated the changes in mechanical energy and the changes in limb length and joint angles. The force carried by the forelimbs and the amount of energy stored was estimated from the distance between elbow and hoof, assuming that this part of the leg behaved as a linear spring. During the forelimb push, the total energy first decreased by 3.2 J kg(-1) and then increased again by 4.2 J kg(-1) to the end of the forelimb push. At the end of the forelimb push, the kinetic energy due to horizontal velocity of the centre of mass was 1.6 J kg(-1) less than at the start, while the effective energy (energy contributing to jump height) was 2.3 J kg(-1) greater. It was investigated to what extent these changes could involve passive spring-like behaviour of the forelimbs. The amount of energy stored and re-utilized in the distal tendons during the forelimb push was estimated to be on average 0.4 J kg(-1) in the trailing forelimb and 0.23 J kg(-1) in the leading forelimb. This means that a considerable amount of energy was first dissipated and subsequently regenerated by muscles, with triceps brachii probably being the most important contributor. During the hindlimb push, the muscles of the leg were primarily producing energy. The total increase in energy was 2.5 J kg(-1) and the peak power output amounted to 71 W kg(-1).

  8. Incomplete swallowing and retracted tongue maneuvers for electromyographic signal normalization of the extrinsic muscles of the larynx.

    Science.gov (United States)

    Balata, Patricia Maria Mendes; Silva, Hilton J; Nascimento, Gerlane Karla O; Moraes, Klyvia Juliana R; Pernambuco, Leandro A; Freitas, Maria Clara R; Lima, Leilane M; Braga, Renata S; Souza, Síntia R; Moraes, Silvia Regina A

    2012-11-01

    To investigate which muscular maneuvers provide larger electric activity (EA) of the suprahyoid (SH) and infrahyoid (IH) muscles to be used as surface electromyography (SEMG) signal normalization reference. The electrical potentials of the SH and IH muscles of 12 subjects were evaluated using six muscular maneuvers, involving the position of the tongue and effort. It was selected as maximum voluntary sustained activity maneuver, the one having the minor coefficient of variation and the smallest value for each muscle group. The EA signal was converted using the root mean square in microvolts. It was considered then the maximum signal of each maneuver as the difference between the mean of three measures and the resting potential. The maneuvers that provided higher mean potentials with minor coefficient of variation and smallest P value were incomplete swallowing (IS) with effort (mean potential equal to 56.73±8.68 with coefficient of variation of 15.30%) in SH group, and tongue retracted with mouth open (TROM, mean potential equal to 46.57±7.83 with coefficient of variation of 16.81%) in IH group. The IS with effort and TROM maneuvers should be considered for signal normalization in these muscles, respectively, and may provide conditions for using the SEMG in voice clinic. The use of normalization standards in researches of SH and IH muscles in the voice area will allow comparisons among future works. Copyright © 2012 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

  9. Neuromuscular anatomy and evolution of the cetacean forelimb.

    Science.gov (United States)

    Cooper, Lisa Noelle; Dawson, Susan D; Reidenberg, Joy S; Berta, Annalisa

    2007-09-01

    The forelimb of cetaceans (whales, dolphins, and porpoises) has been radically modified during the limb-to-flipper transition. Extant cetaceans have a soft tissue flipper encasing the manus and acting as a hydrofoil to generate lift. The neuromuscular anatomy that controls flipper movement, however, is poorly understood. This study documents flipper neuromuscular anatomy and tests the hypothesis that antebrachial muscle robustness is related to body size. Data were gathered during dissections of 22 flippers, representing 15 species (7 odontocetes, 15 mysticetes). Results were compared with published descriptions of both artiodactyls and secondarily aquatic vertebrates. Results indicate muscle robustness is best predicted by taxonomic distribution and is not a function of body size. All cetaceans have atrophied triceps muscles, an immobile cubital joint, and lack most connective tissue structures and manus muscles. Forelimbs retain only three muscle groups: triceps (only the scapular head is functional as the humeral heads are vestigal), and antebrachial extensors and flexors. Well-developed flexor and extensor muscles were found in mysticetes and basal odontocetes (i.e., physeterids, kogiids, and ziphiids), whereas later diverging odontocetes (i.e., monodontids, phocoenids, and delphinids) lack or reduce these muscles. Balaenopterid mysticetes (e.g., fin and minke whales) may actively change flipper curvature, while basal odontocetes (e.g., sperm and beaked whales) probably stiffen the flipper through isometric contraction. Later diverging odontocetes lack musculature supporting digital movements and are unable to manipulate flipper curvature. Cetacean forelimbs are unique in that they have lost agility and several soft tissue structures, but retain sensory innervations.

  10. Functional anatomy of the cheetah (Acinonyx jubatus) forelimb.

    Science.gov (United States)

    Hudson, Penny E; Corr, Sandra A; Payne-Davis, Rachel C; Clancy, Sinead N; Lane, Emily; Wilson, Alan M

    2011-04-01

    Despite the cheetah being the fastest living land mammal, we know remarkably little about how it attains such high top speeds (29 m s(-1)). Here we aim to describe and quantify the musculoskeletal anatomy of the cheetah forelimb and compare it to the racing greyhound, an animal of similar mass, but which can only attain a top speed of 17 m s(-1). Measurements were made of muscle mass, fascicle length and moment arms, enabling calculations of muscle volume, physiological cross-sectional area (PCSA), and estimates of joint torques and rotational velocities. Bone lengths, masses and mid-shaft cross-sectional areas were also measured. Several species differences were observed and have been discussed, such as the long fibred serratus ventralis muscle in the cheetah, which we theorise may translate the scapula along the rib cage (as has been observed in domestic cats), thereby increasing the cheetah's effective limb length. The cheetah's proximal limb contained many large PCSA muscles with long moment arms, suggesting that this limb is resisting large ground reaction force joint torques and therefore is not functioning as a simple strut. Its structure may also reflect a need for control and stabilisation during the high-speed manoeuvring in hunting. The large digital flexors and extensors observed in the cheetah forelimb may be used to dig the digits into the ground, aiding with traction when galloping and manoeuvring. © 2011 The Authors. Journal of Anatomy © 2011 Anatomical Society of Great Britain and Ireland.

  11. Awake behaving electrophysiological correlates of forelimb hyperreflexia, weakness and disrupted muscular synchronization following cervical spinal cord injury in the rat

    Science.gov (United States)

    Ganzer, Patrick Daniel; Meyers, Eric Christopher; Sloan, Andrew Michael; Maliakkal, Reshma; Ruiz, Andrea; Kilgard, Michael Paul; Rennaker, Robert LeMoine

    2016-01-01

    Spinal cord injury usually occurs at the level of the cervical spine and results in profound impairment of forelimb function. In this study, we recorded awake behaving intramuscular electromyography (EMG) from the biceps and triceps muscles of the impaired forelimb during volitional and reflexive forelimb movements before and after unilateral cervical spinal cord injury (cSCI) in rats. C5/C6 hemicontusion reduced volitional forelimb strength by more than 50% despite weekly rehabilitation for one month post-injury. Triceps EMG during volitional strength assessment was reduced by more than 60% following injury, indicating reduced descending drive. Biceps EMG during reflexive withdrawal from a thermal stimulus was increased by 500% following injury, indicating flexor withdrawal hyperreflexia. The reduction in volitional forelimb strength was significantly correlated with volitional and reflexive biceps EMG activity. Our results support the hypothesis that biceps hyperreflexia and descending volitional drive both significantly contribute to forelimb strength deficits after cSCI and provide new insight into dynamic muscular dysfunction after cSCI. The use of multiple automated quantitative measures of forelimb dys-function in the rodent cSCI model will likely aid the search for effective regenerative, pharmacological, and neuroprosthetic treatments for spinal cord injury. PMID:27033345

  12. Functional morphology of the forelimb of living and extinct tree-kangaroos (Marsupialia: Macropodidae).

    Science.gov (United States)

    Warburton, Natalie M; Harvey, Kathryn J; Prideaux, Gavin J; O'Shea, James E

    2011-10-01

    Tree-kangaroos are a unique group of arboreal marsupials that evolved from terrestrial ancestors. The recent discovery of well-preserved specimens of extinct tree-kangaroo species (genus Bohra) within Pleistocene cave deposits of south-central Australia provides a unique opportunity to examine adaptive evolution of tree-kangaroos. Here, we provide the first detailed description of the functional anatomy of the forelimb, a central component of the locomotor complex, in the extant Dendrolagus lumholtzi, and compare its structure and function with representatives of other extant marsupial families. Several features were interpreted as adaptations for coping with a discontinuous, uneven and three-dimensional arboreal substrate through enhanced muscular strength and dexterity for propulsion, grasping, and gripping with the forelimbs. The forelimb musculoskeletal anatomy of Dendrolagus differed from terrestrial kangaroos in the following principal ways: a stronger emphasis on the development of muscles groups responsible for adduction, grasping, and gripping; the enlargement of muscles that retract the humerus; and modified shape of the scapula and bony articulations of the forelimb bones to allow improved mobility. Many of these attributes are convergent with other arboreal marsupials. Tree-kangaroos, however, still retain the characteristic bauplan of their terrestrial ancestors, particularly with regard to skeletal morphology, and the muscular anatomy of the forelimb highlights a basic conservatism within the group. In many instances, the skeletal remains of Bohra have similar features to Dendrolagus that suggest adaptations to an arboreal habit. Despite the irony of their retrieval from deposits of the Nullarbor "Treeless" Plain, forelimb morphology clearly shows that the species of Bohra were well adapted to an arboreal habitat.

  13. Precocial hindlimbs and altricial forelimbs: partitioning ontogenetic strategies in mallards (Anas platyrhynchos).

    Science.gov (United States)

    Dial, Terry R; Carrier, David R

    2012-11-01

    Precocial development, in which juveniles are relatively mature at hatching or birth, is more common among vertebrates than altricial development, and is likely to be the basal condition. Altricial development characterizes many birds and mammals and is generally viewed as an alternate strategy, promoting fast growth rates, short developmental periods and relatively poor locomotor performance prior to attaining adult size. Many aquatic birds such as Anseriformes (ducks, geese and swans), Charadriformes (gulls and terns) and Gruiformes (rails) undergo distinctive developmental trajectories, in that hatchlings are able to run and swim the day they hatch, yet they do not begin to fly until fully grown. We hypothesized that there should be tradeoffs in apportioning bone and muscle mass to the hindlimb and forelimb that could account for these patterns in locomotor behavior within the mallard (Anas platyrhynchos). Growth of the musculoskeletal system in the forelimbs and hindlimbs was measured and compared with maximal aquatic and terrestrial sprint speeds and aerial descent rates throughout the 2-month-long mallard ontogenetic period. At 30 days post hatching, when body mass is 50% of adult values, hindlimb muscle mass averages 90% and forelimb muscle mass averages 10% of adult values; similarly, bone growth (length and width) in the hindlimbs and forelimbs averages 90 and 60% of adult values, respectively. The attainment of mallard locomotor performance parallels the morphological maturation of forelimb and hindlimb morphometrics - hindlimb performance initiates just after hatching at a relatively high level (~50% adult values) and gradually improves throughout the first month of development, while forelimb performance is relatively non-existent at hatching (~10% adult values), experiencing delayed and dramatic improvement in function, and maturing at the time of fledging. This divergence in ontogenetic strategy between locomotor modules could allow developing

  14. Extrinsic Curvature Embedding Diagrams

    CERN Document Server

    Lu, J L

    2003-01-01

    Embedding diagrams have been used extensively to visualize the properties of curved space in Relativity. We introduce a new kind of embedding diagram based on the {\\it extrinsic} curvature (instead of the intrinsic curvature). Such an extrinsic curvature embedding diagram, when used together with the usual kind of intrinsic curvature embedding diagram, carries the information of how a surface is {\\it embedded} in the higher dimensional curved space. Simple examples are given to illustrate the idea.

  15. Muscular reconstruction and functional morphology of the forelimb of early Miocene sloths (Xenarthra, Folivora) of Patagonia.

    Science.gov (United States)

    Toledo, Néstor; Bargo, M Susana; Vizcaíno, Sergio F

    2013-02-01

    Early Miocene sloths are represented by a diversity of forms ranging from 38 to 95 kg, being registered mainly from Santacrucian Age deposits in southern-most shores of Patagonia, Argentina. Their postcranial skeleton differs markedly in shape from those of their closest living relatives (arboreal forms of less than 10 kg), Bradypus and Choloepus. In order to gain insight on functional properties of the Santacrucian sloths forelimb, musculature was reconstructed and a comparative, qualitative morphofunctional analysis was performed, allowing proposing hypotheses about biological role of the limb in substrate preferences, and locomotor strategies. The anatomy of the forelimb of Santacrucian sloths resembles more closely extant anteaters such as Tamandua and Myrmecophaga, due to the robustness of the elements, development of features related to attachment of ligaments and muscles, and conservative, pentadactylous, and strong-clawed manus. The reconstructed forelimb musculature was very well developed and resembles that of extant Pilosa (especially anteaters), although retaining the basic muscular configuration of generalized mammals. This musculature allowed application of powerful forces, especially in adduction of the forelimb, flexion and extension of the antebrachium, and manual prehension. These functional properties are congruent with both climbing and digging activities, and provide support for proposed Santacrucian sloths as good climbing mammals, possibly arboreal or semiarboreal, being also capable diggers. Their climbing strategies were limited, thus these forms relied mainly on great muscular strength and curved claws of the manus to move cautiously on branches.

  16. Cervical intraspinal microstimulation evokes robust forelimb movements before and after injury

    Science.gov (United States)

    Sunshine, Michael D.; Cho, Frances S.; Lockwood, Danielle R.; Fechko, Amber S.; Kasten, Michael R.; Moritz, Chet T.

    2013-06-01

    Objective. Intraspinal microstimulation (ISMS) is a promising method for reanimating paralyzed limbs following neurological injury. ISMS within the cervical and lumbar spinal cord is capable of evoking a variety of highly-functional movements prior to injury, but the ability of ISMS to evoke forelimb movements after cervical spinal cord injury is unknown. Here we examine the forelimb movements and muscles activated by cervical ISMS both before and after contusion injury. Approach. We documented the forelimb muscles activated and movements evoked via systematic stimulation of the rodent cervical spinal cord both before injury and three, six and nine weeks following a moderate C4/C5 lateralized contusion injury. Animals were anesthetized with isoflurane to permit construction of somatotopic maps of evoked movements and quantify evoked muscle synergies between cervical segments C3 and T1. Main results. When ISMS was delivered to the cervical spinal cord, a variety of responses were observed at 68% of locations tested, with a spatial distribution that generally corresponded to the location of motor neuron pools. Stimulus currents required to achieve movement and the number of sites where movements could be evoked were unchanged by spinal cord injury. A transient shift toward extension-dominated movements and restricted muscle synergies were observed at three and six weeks following injury, respectively. By nine weeks after injury, however, ISMS-evoked patterns were similar to spinally-intact animals. Significance. The results demonstrate the potential for cervical ISMS to reanimate hand and arm function following spinal cord injury. Robust forelimb movements can be evoked both before and during the chronic stages of recovery from a clinically relevant and sustained cervical contusion injury.

  17. Elbow joint adductor moment arm as an indicator of forelimb posture in extinct quadrupedal tetrapods.

    Science.gov (United States)

    Fujiwara, Shin-ichi; Hutchinson, John R

    2012-07-07

    Forelimb posture has been a controversial aspect of reconstructing locomotor behaviour in extinct quadrupedal tetrapods. This is partly owing to the qualitative and subjective nature of typical methods, which focus on bony articulations that are often ambiguous and unvalidated postural indicators. Here we outline a new, quantitatively based forelimb posture index that is applicable to a majority of extant tetrapods. By determining the degree of elbow joint adduction/abduction mobility in several tetrapods, the carpal flexor muscles were determined to also play a role as elbow adductors. Such adduction may play a major role during the stance phase in sprawling postures. This role is different from those of upright/sagittal and sloth-like creeping postures, which, respectively, depend more on elbow extensors and flexors. Our measurements of elbow muscle moment arms in 318 extant tetrapod skeletons (Lissamphibia, Synapsida and Reptilia: 33 major clades and 263 genera) revealed that sprawling, sagittal and creeping tetrapods, respectively, emphasize elbow adductor, extensor and flexor muscles. Furthermore, scansorial and non-scansorial taxa, respectively, emphasize flexors and extensors. Thus, forelimb postures of extinct tetrapods can be qualitatively classified based on our quantitative index. Using this method, we find that Triceratops (Ceratopsidae), Anhanguera (Pterosauria) and desmostylian mammals are categorized as upright/sagittally locomoting taxa.

  18. The phylogeny of the red panda (Ailurus fulgens): evidence from the forelimb

    Science.gov (United States)

    Fisher, Rebecca E; Adrian, Brent; Barton, Michael; Holmgren, Jennifer; Tang, Samuel Y

    2009-01-01

    Within the order Carnivora, the phylogeny of the red panda (Ailurus fulgens) is contentious, with morphological and molecular studies supporting a wide range of possible relationships, including close ties to procyonids, ursids, mustelids and mephitids. This study provides additional morphological data, including muscle maps, for the forelimb of Ailurus, based on the dissection of four cadavers from the National Zoological Park, Washington, DC, USA. The red panda forelimb is characterized by a number of primitive features, including the lack of m. rhomboideus profundus, a humeral insertion for m. cleidobrachialis, the presence of mm. brachioradialis, articularis humeri and coracobrachialis, a single muscle belly for m. extensor digitorum lateralis with tendons to digits III–V, four mm. lumbricales, and the presence of mm. flexor digitorum brevis manus, adductores digiti I, II and V, and abductor digiti I and V. Red pandas resemble Ailuropoda, mustelids and some procyonids in possessing a soft tissue origin of m. flexor digitorum superficialis. In addition, red pandas are similar to ursids and procyonids in having a variable presence of m. biceps brachii caput breve. Furthermore, Ailurus and some ursids lack m. rhomboideus capitis. The forelimb muscle maps from this study represent a valuable resource for analyzing the functional anatomy of fossil ailurids and some notes on the Miocene ailurid, Simocyon batalleri, are presented. PMID:19930516

  19. Elbow joint adductor moment arm as an indicator of forelimb posture in extinct quadrupedal tetrapods

    Science.gov (United States)

    Fujiwara, Shin-ichi; Hutchinson, John R.

    2012-01-01

    Forelimb posture has been a controversial aspect of reconstructing locomotor behaviour in extinct quadrupedal tetrapods. This is partly owing to the qualitative and subjective nature of typical methods, which focus on bony articulations that are often ambiguous and unvalidated postural indicators. Here we outline a new, quantitatively based forelimb posture index that is applicable to a majority of extant tetrapods. By determining the degree of elbow joint adduction/abduction mobility in several tetrapods, the carpal flexor muscles were determined to also play a role as elbow adductors. Such adduction may play a major role during the stance phase in sprawling postures. This role is different from those of upright/sagittal and sloth-like creeping postures, which, respectively, depend more on elbow extensors and flexors. Our measurements of elbow muscle moment arms in 318 extant tetrapod skeletons (Lissamphibia, Synapsida and Reptilia: 33 major clades and 263 genera) revealed that sprawling, sagittal and creeping tetrapods, respectively, emphasize elbow adductor, extensor and flexor muscles. Furthermore, scansorial and non-scansorial taxa, respectively, emphasize flexors and extensors. Thus, forelimb postures of extinct tetrapods can be qualitatively classified based on our quantitative index. Using this method, we find that Triceratops (Ceratopsidae), Anhanguera (Pterosauria) and desmostylian mammals are categorized as upright/sagittally locomoting taxa. PMID:22357261

  20. The forelimb of Tyrannosaurus rex: a pathetic vestigial organ or an integral part of a fearsome predator?

    Science.gov (United States)

    Lee, Scott A.; Thomas, Joshua

    2014-03-01

    The function of the forelimb of Tyrannosaurus rex remains a controversial topic since it was too short to transfer food directly to the mouth. Since Tyrannosaurus rex was bipedal, the forelimb was not involved in locomotion. Suggestions for its possible use include providing an initial push for a laying animal to stand or to hold position during mating. We report numerical calculations performed to determine the moment of inertia of the forearm and the torques generated by the muscles of the arm, based on three-dimensional representations of the forelimb. Our results imply that the forelimb was capable of very high angular accelerations, on the order of 130 radians/s2. This corresponds to a tangential acceleration of the manus on the order of 90 m/s2 or about 9g, indicating that the manus could be moved extremely quickly to control a struggling prey animal immediately before the death blow was delivered by the teeth of Tyrannosaurus rex. Rather than a pathetic vestigial organ, these calculations suggest that the forelimbs were an integral part of the predation tactics of Tyrannosaurus rex.

  1. New, puzzling insights from comparative myological studies on the old and unsolved forelimb/hindlimb enigma.

    Science.gov (United States)

    Diogo, Rui; Linde-Medina, Marta; Abdala, Virginia; Ashley-Ross, Miriam A

    2013-02-01

    Most textbooks and research reports state that the structures of the tetrapod forelimbs and hindlimbs are serial homologues. From this view, the main challenge of evolutionary biologists is not to explain the similarity between tetrapod limbs, but instead to explain why and how they have diverged. However, these statements seem to be related to a confusion between the serial homology of the vertebrate pelvic and pectoral appendages as a whole, and the serial homology of the specific soft- and hard-tissue structures of the tetrapod forelimbs and hindlimbs, leading to an even more crucial and puzzling question being overlooked: why are the skeletal and particularly the muscle structures of the forelimb and hindlimb actually so strikingly similar to each other? Herein we provide an updated discussion of these questions and test two main hypotheses: (i) that the similarity of the limb muscles is due to serial homology; and (ii) that tetrapods that use hindlimbs for a largely exclusive function (e.g. bipedalism in humans) exhibit fewer cases of similarity between forelimbs and hindlimbs than do quadrupedal species. Our review shows that of the 23 arm, forearm and hand muscles/muscle groups of salamanders, 18 (78%) have clear 'topological equivalents' in the hindlimb; in lizards, 14/24 (58%); in rats, 14/35 (40%); and in modern humans, 19/37 (51%). These numbers seem to support the idea that there is a plesiomorphic similarity and subsequent evolutionary divergence, but this tendency actually only applies to the three former quadrupedal taxa. Moreover, if one takes into account the total number of 'correspondences', one comes to a surprising and puzzling conclusion: in modern humans the number of forelimb muscles/muscle groups with clear 'equivalents' in the hindlimb (19) is substantially higher than in quadrupedal mammals such as rats (14), lizards (14) and even salamanders (18). These data contradict the hypothesis that divergent functions lead to divergent

  2. Extrinsic and intrinsic regulation of DOR/TP53INP2 expression in mice: effects of dietary fat content, tissue type and sex in adipose and muscle tissues.

    Science.gov (United States)

    Fromm-Dornieden, Carolin; Lytovchenko, Oleksandr; von der Heyde, Silvia; Behnke, Nina; Hogl, Sebastian; Berghoff, Janina; Köpper, Frederik; Opitz, Lennart; Renne, Ulla; Hoeflich, Andreas; Beissbarth, Tim; Brenig, Bertram; Baumgartner, Bernhard G

    2012-09-21

    DOR/TP53INP2 acts both at the chromosomal level as a nuclear co-factor e.g. for the thyroid hormone receptor and at the extrachromosomal level as an organizing factor of the autophagosome. In a previous study, DOR was shown to be down-regulated in skeletal muscle of obese diabetic Zucker fa/fa rats. To identify sites of differential DOR expression in metabolically active tissues, we measured differences in DOR expression in white adipose tissue (WAT), brown adipose tissue (BAT), skeletal muscle (SM) and heart muscle (HM) by qPCR. To assess whether DOR expression is influenced in the short term by nutritional factors, NMRI mice were fed different fat rich diets (fat diet, FD: 18% or high fat diet, HFD: 80% fat) for one week and DOR expression was compared to NMRI mice fed a control diet (normal diet, ND: 3.3% fat). Additionally, DOR expression was measured in young (45 days old) and adult (100 days old) genetically obese (DU6/DU6i) mice and compared to control (DUKs/DUKsi) animals. ANOVA results demonstrate a significant influence of diet, tissue type and sex on DOR expression in adipose and muscle tissues of FD and HFD mice. In SM, DOR expression was higher in HFD than in FD male mice. In WAT, DOR expression was increased compared to BAT in male FD and HFD mice. In contrast, expression levels in female mice were higher in BAT for both dietary conditions.DOR expression levels in all tissues of 100 days old genetically obese animals were mainly influenced by sex. In HM, DOR expression was higher in male than female animals. DOR expression varies under the influence of dietary fat content, tissue type and sex. We identified target tissues for further studies to analyze the specific function of DOR in obesity. DOR might be part of a defense mechanism against fat storage in high fat diets or obesity.

  3. Extrinsic allergic alveolitis.

    Science.gov (United States)

    Ismail, Tengku; McSharry, Charles; Boyd, Gavin

    2006-05-01

    Extrinsic allergic alveolitis (also known as hypersensitivity pneumonitis) is caused by repeated inhalation of mainly organic antigens by sensitized subjects. This induces a hypersensitivity response in the distal bronchioles and alveoli and subjects may present clinically with a variety of symptoms. The aims of this review are to describe the current concepts of the immunological response, the diverse clinical presentation of this disease, the relevant investigations and management, and areas for future studies.

  4. Phylogeny and forelimb disparity in waterbirds.

    Science.gov (United States)

    Wang, Xia; Clarke, Julia A

    2014-10-01

    Previous work has shown that the relative proportions of wing components (i.e., humerus, ulna, carpometacarpus) in birds are related to function and ecology, but these have rarely been investigated in a phylogenetic context. Waterbirds including "Pelecaniformes," Ciconiiformes, Procellariiformes, Sphenisciformes, and Gaviiformes form a highly supported clade and developed a great diversity of wing forms and foraging ecologies. In this study, forelimb disparity in the waterbird clade was assessed in a phylogenetic context. Phylogenetic signal was assessed via Pagel's lambda, Blomberg's K, and permutation tests. We find that different waterbird clades are clearly separated based on forelimb component proportions, which are significantly correlated with phylogeny but not with flight style. Most of the traditional contents of "Pelecaniformes" (e.g., pelicans, cormorants, and boobies) cluster with Ciconiiformes (herons and storks) and occupy a reduced morphospace. These taxa are closely related phylogenetically but exhibit a wide range of ecologies and flight styles. Procellariiformes (e.g., petrels, albatross, and shearwaters) occupy a wide range of morphospace, characterized primarily by variation in the relative length of carpometacarpus and ulna. Gaviiformes (loons) surprisingly occupy a wing morphospace closest to diving petrels and penguins. Whether this result may reflect wing proportions plesiomorphic for the waterbird clade or a functional signal is unclear. A Bayesian approach detecting significant rate shifts across phylogeny recovered two such shifts. At the base of the two sister clades Sphenisciformes + Procellariiformes, a shift to an increase evolutionary rate of change is inferred for the ulna and carpometacarpus. Thus, changes in wing shape begin prior to the loss of flight in the wing-propelled diving clade. Several shifts to slower rate of change are recovered within stem penguins. © 2014 The Author(s). Evolution © 2014 The Society for the Study of

  5. Forelimb Myology of Carnivorous Marsupials (Marsupialia: Dasyuridae): Implications for the Ancestral Body Plan of the Australidelphia.

    Science.gov (United States)

    Warburton, Natalie M; Marchal, Charlie-Rose

    2017-09-01

    Carnivorous marsupials of the family Dasyuridae represent a more generalized anatomical condition of both craniodental and postcranial features in comparison to other groups of Australidelphian marsupials. Plesiomorphic characters include polyprotodont dentition, didactylous (rather than syndactylous) pedal morphology, the retention of clavicles and epipubic bones, and an unossified patelloid. In light of the anatomy of the postcranial skeleton, we hypothesized that the muscular anatomy of the Dasyuridae would likely display a range of plesiomorphic traits. We performed gross anatomical dissection on the forelimbs of four species of dasyurid marsupials to produce anatomical descriptions and muscle origin and insertion maps for Dasyurus geoffroii, D. hallucatus, and Phascogale tapoatafa, together with comparative notes for Antechinus flavipes. These new descriptions were then compared with those of other marsupials from the published literature in order to establish the principal patterns in forelimb muscular anatomy. In nearly all aspects of anatomy, we found that the arrangement of the muscular origins and insertions, and the relative degree of separation between muscle bellies among dasyurids, provide a natural starting point from which the anatomies of other Australidelphian marsupial groups can be derived. Anat Rec, 300:1589-1608, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  6. A series of rat segmental forelimb ectopic implantation models.

    Science.gov (United States)

    Zhou, Xianyu; Luo, Xusong; Gao, Bowen; Liu, Fei; Gu, Chuan; Yu, Qingxiong; Li, Qingfeng; Zhu, Hainan

    2017-05-09

    Temporary ectopic implantation has been performed in clinical practice to salvage devascularized amputated tissues for delayed replantation purpose. In this study, we established a series of segmental forelimb ectopic implantation models in rats, including forelimb, forearm, forepaw, digit, and double forelimbs, to mimic the clinical context. Time of amputated limbs harvesting in donors and ectopic implantation process in recipients were recorded. Survival time and mortalities of recipients were also recorded. Sixty days after ectopic implantation, a full-field laser perfusion imager (FLPI) was used to detect the blood flow of amputated limbs and micro-CT imaging was used to examine bone morphological changes. Histological sections of amputated limbs were stained with hematoxylin and eosin to evaluate pathological changes. Implanted amputated limbs in all models achieved long term survival and there were no obvious morphological and histological changes were found according to results of micro-CT and histology study. Thus, a series of rat segmental forelimb temporary ectopic implantation models have been well established. To our knowledge, this is the first rodent animal model related to forelimb temporary ectopic implantation. These models might facilitate further research related to salvage, reconstruction and better aesthetic and functional outcome of upper extremity/digit in temporary ectopic implantation scenario.

  7. Peripheral neuropathy of a forelimb in horses: 27 cases (2000-2013).

    Science.gov (United States)

    Emond, Anne-Laure; Bertoni, Lélia; Seignour, Maeva; Coudry, Virginie; Denoix, Jean-Marie

    2016-11-15

    OBJECTIVE To describe the clinical features, diagnostic procedures, management, and outcome of horses with peripheral neuropathy of a forelimb. DESIGN Retrospective case series. ANIMALS 27 horses. PROCEDURES Records from 2000 to 2013 were reviewed to identify horses with peripheral neuropathy of a forelimb. Horses were grouped as having predominant lesions of a suprascapular nerve, axillary nerve, or radial nerve (alone or in association with other brachial plexus nerves) on the basis of physical examination and diagnostic imaging findings. Treatments were primarily conservative. Signalment, history, lameness characteristics, diagnostic imaging features, case management, and outcomes were evaluated. RESULTS Predominant lesions of a suprascapular nerve, axillary nerve, and radial nerve were identified in 11, 2, and 14 horses, respectively. Eight horses with predominant suprascapular nerve injury and 9 with injury to a radial nerve alone or in association with other nerves returned to their previous activity level or intended use after mean recovery periods of 9.3 and 13.3 months, respectively; 2 horses with a predominant axillary nerve injury had this outcome after a mean 3.5-month recovery period. Ultrasonography was useful for evaluation of muscle atrophy and other injuries during the initial examination (in 27 horses) and the rehabilitation period (in 7 horses). CONCLUSIONS AND CLINICAL RELEVANCE Most horses with peripheral neuropathy of a forelimb returned to athletic soundness following an adequate period of rest. Horses with lesions of a radial nerve alone or in association with other nerves typically required longer recovery times than did those with predominant injuries of a suprascapular nerve.

  8. Therapeutic intraspinal microstimulation improves forelimb function after cervical contusion injury

    Science.gov (United States)

    Kasten, M. R.; Sunshine, M. D.; Secrist, E. S.; Horner, P. J.; Moritz, C. T.

    2013-08-01

    Objective. Intraspinal microstimulation (ISMS) is a promising method for activating the spinal cord distal to an injury. The objectives of this study were to examine the ability of chronically implanted stimulating wires within the cervical spinal cord to (1) directly produce forelimb movements, and (2) assess whether ISMS stimulation could improve subsequent volitional control of paretic extremities following injury. Approach. We developed a technique for implanting intraspinal stimulating electrodes within the cervical spinal cord segments C6-T1 of Long-Evans rats. Beginning 4 weeks after a severe cervical contusion injury at C4-C5, animals in the treatment condition received therapeutic ISMS 7 hours/day, 5 days/week for the following 12 weeks. Main results. Over 12 weeks of therapeutic ISMS, stimulus-evoked forelimb movements were relatively stable. We also explored whether therapeutic ISMS promoted recovery of forelimb reaching movements. Animals receiving daily therapeutic ISMS performed significantly better than unstimulated animals during behavioural tests conducted without stimulation. Quantitative video analysis of forelimb movements showed that stimulated animals performed better in the movements reinforced by stimulation, including extending the elbow to advance the forelimb and opening the digits. While threshold current to elicit forelimb movement gradually increased over time, no differences were observed between chronically stimulated and unstimulated electrodes suggesting that no additional tissue damage was produced by the electrical stimulation. Significance. The results indicate that therapeutic intraspinal stimulation delivered via chronic microwire implants within the cervical spinal cord confers benefits extending beyond the period of stimulation, suggesting future strategies for neural devices to promote sustained recovery after injury.

  9. Carpal myxosarcoma and forelimb amputation in a ferret

    NARCIS (Netherlands)

    van Zeeland, Y.R.A.; Hernandez-Divers, S.J.; Blasier, M.W.; Vila-Garcia, G.; Delong, D.; Stedman, N.L.

    2006-01-01

    Vet Rec. 2006 Dec 2;159(23):782-5. Carpal myxosarcoma and forelimb amputation in a ferret (Mustela putorius furo). van Zeeland YR, Hernandez-Divers SJ, Blasier MW, Vila-Garcia G, Delong D, Stedman NL. Department of Small Animal Medicine, Faculty of Veterinary Medicine, University of Utrecht, Utrecht

  10. Carpal myxosarcoma and forelimb amputation in a ferret

    NARCIS (Netherlands)

    van Zeeland, Y.R.A.; Hernandez-Divers, S.J.; Blasier, M.W.; Vila-Garcia, G.; Delong, D.; Stedman, N.L.

    2006-01-01

    Vet Rec. 2006 Dec 2;159(23):782-5. Carpal myxosarcoma and forelimb amputation in a ferret (Mustela putorius furo). van Zeeland YR, Hernandez-Divers SJ, Blasier MW, Vila-Garcia G, Delong D, Stedman NL. Department of Small Animal Medicine, Faculty of Veterinary Medicine, University of Utrecht, Utrecht

  11. Forelimb-hindlimb developmental timing changes across tetrapod phylogeny

    Directory of Open Access Journals (Sweden)

    Selwood Lynne

    2007-10-01

    Full Text Available Abstract Background Tetrapods exhibit great diversity in limb structures among species and also between forelimbs and hindlimbs within species, diversity which frequently correlates with locomotor modes and life history. We aim to examine the potential relation of changes in developmental timing (heterochrony to the origin of limb morphological diversity in an explicit comparative and quantitative framework. In particular, we studied the relative time sequence of development of the forelimbs versus the hindlimbs in 138 embryos of 14 tetrapod species spanning a diverse taxonomic, ecomorphological and life-history breadth. Whole-mounts and histological sections were used to code the appearance of 10 developmental events comprising landmarks of development from the early bud stage to late chondrogenesis in the forelimb and the corresponding serial homologues in the hindlimb. Results An overall pattern of change across tetrapods can be discerned and appears to be relatively clade-specific. In the primitive condition, as seen in Chondrichthyes and Osteichthyes, the forelimb/pectoral fin develops earlier than the hindlimb/pelvic fin. This pattern is either retained or re-evolved in eulipotyphlan insectivores (= shrews, moles, hedgehogs, and solenodons and taken to its extreme in marsupials. Although exceptions are known, the two anurans we examined reversed the pattern and displayed a significant advance in hindlimb development. All other species examined, including a bat with its greatly enlarged forelimbs modified as wings in the adult, showed near synchrony in the development of the fore and hindlimbs. Conclusion Major heterochronic changes in early limb development and chondrogenesis were absent within major clades except Lissamphibia, and their presence across vertebrate phylogeny are not easily correlated with adaptive phenomena related to morphological differences in the adult fore- and hindlimbs. The apparently conservative nature of this

  12. Extrinsic electromagnetic chirality in metamaterials

    OpenAIRE

    Plum, E.; Fedotov, V. A.; Zheludev, N. I.

    2009-01-01

    Three- and two-dimensional chirality arising from the mutual orientation of non-chiral planar metamaterial structures and the incident electromagnetic wave (extrinsic chirality) lead to pronounced optical activity, circular dichroism and asymmetric transmission indistinguishable from those seen in media consisting of three- and two-dimensionally chiral molecules (intrinsic chirality).

  13. Population coding of forelimb joint kinematics by peripheral afferents in monkeys.

    Directory of Open Access Journals (Sweden)

    Tatsuya Umeda

    Full Text Available Various peripheral receptors provide information concerning position and movement to the central nervous system to achieve complex and dexterous movements of forelimbs in primates. The response properties of single afferent receptors to movements at a single joint have been examined in detail, but the population coding of peripheral afferents remains poorly defined. In this study, we obtained multichannel recordings from dorsal root ganglion (DRG neurons in cervical segments of monkeys. We applied the sparse linear regression (SLiR algorithm to the recordings, which selects useful input signals to reconstruct movement kinematics. Multichannel recordings of peripheral afferents were performed by inserting multi-electrode arrays into the DRGs of lower cervical segments in two anesthetized monkeys. A total of 112 and 92 units were responsive to the passive joint movements or the skin stimulation with a painting brush in Monkey 1 and Monkey 2, respectively. Using the SLiR algorithm, we reconstructed the temporal changes of joint angle, angular velocity, and acceleration at the elbow, wrist, and finger joints from temporal firing patterns of the DRG neurons. By automatically selecting a subset of recorded units, the SLiR achieved superior generalization performance compared with a regularized linear regression algorithm. The SLiR selected not only putative muscle units that were responsive to only the passive movements, but also a number of putative cutaneous units responsive to the skin stimulation. These results suggested that an ensemble of peripheral primary afferents that contains both putative muscle and cutaneous units encode forelimb joint kinematics of non-human primates.

  14. Extrinsic incentives and tax compliance

    OpenAIRE

    Sour, Laura; Gutiérrez Andrade, Miguel Ángel

    2011-01-01

    This paper models the impact of extrinsic incentives in a tax compliance model. It also provides experimental evidence that confirms the existence of a positive relationship between rewards and tax compliance. If individuals are audited, rewards for honest taxpayers are effective in increasing the level of tax compliance. These results are particularly relevant in countries where there is little respect for tax law since rewards can contribute to crowding in the intrinsic motivation to comply.

  15. Extrinsic incentives and tax compliance

    OpenAIRE

    Sour, Laura; Gutiérrez Andrade, Miguel Ángel

    2011-01-01

    This paper models the impact of extrinsic incentives in a tax compliance model. It also provides experimental evidence that confirms the existence of a positive relationship between rewards and tax compliance. If individuals are audited, rewards for honest taxpayers are effective in increasing the level of tax compliance. These results are particularly relevant in countries where there is little respect for tax law since rewards can contribute to crowding in the intrinsic motivation to comply.

  16. Wide Bandgap Extrinsic Photoconductive Switches

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, James S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2013-07-03

    Semi-insulating Gallium Nitride, 4H and 6H Silicon Carbide are attractive materials for compact, high voltage, extrinsic, photoconductive switches due to their wide bandgap, high dark resistance, high critical electric field strength and high electron saturation velocity. These wide bandgap semiconductors are made semi-insulating by the addition of vanadium (4H and 6HSiC) and iron (2H-GaN) impurities that form deep acceptors. These deep acceptors trap electrons donated from shallow donor impurities. The electrons can be optically excited from these deep acceptor levels into the conduction band to transition the wide bandgap semiconductor materials from a semi-insulating to a conducting state. Extrinsic photoconductive switches with opposing electrodes have been constructed using vanadium compensated 6H-SiC and iron compensated 2H-GaN. These extrinsic photoconductive switches were tested at high voltage and high power to determine if they could be successfully used as the closing switch in compact medical accelerators.

  17. Lesion in the lateral cerebellum specifically produces overshooting of the toe trajectory in leading forelimb during obstacle avoidance in the rat.

    Science.gov (United States)

    Aoki, Sho; Sato, Yamato; Yanagihara, Dai

    2013-10-01

    During locomotion, stepping over an obstacle under visual guidance is crucial to continuous safe walking. Studies of the role of the central nervous system in stepping movements have focused on cerebral cortical areas such as the primary motor cortex and posterior parietal cortex. There is speculation that the lateral cerebellum, which has strong anatomical connections with the cerebral cortex, also plays a key role in stepping movements over an obstacle, although this function of the lateral cerebellum has not yet been elucidated. Here we investigated the role of the lateral cerebellum during obstacle avoidance locomotion in rats with a lateral cerebellar lesion. A unilateral lesion in the lateral cerebellum did not affect limb movements during overground locomotion. Importantly, however, the lesioned animals showed overshooting of the toe trajectory specific to the leading forelimb ipsilateral to the lesion when stepping over an obstacle, and the peak toe position, in which the toe is maximally raised during stepping, shifted away from the upper edge of the obstacle. Recordings of EMG activity from elbow flexor and extensor muscles suggested that the overshooting toe trajectory in the ipsilateral leading forelimb possibly resulted from sustained elbow flexion and delayed elbow extension following prolonged activity of the biceps brachii. These results suggest that the lateral cerebellum specifically contributes to generating appropriate toe trajectories in the ipsilateral leading forelimb and to controlling related muscle activities in stepping over an obstacle, especially when accurate control of the distal extremity is achieved under visual guidance.

  18. A Stringy (Holographic) Pomeron with Extrinsic Curvature

    CERN Document Server

    Qian, Yachao

    2014-01-01

    We model the soft pomeron in QCD using a scalar Polyakov string with extrinsic curvature in the bottom-up approach of holographic QCD. The overall dipole-dipole scattering amplitude in the soft pomeron kinematics is shown to be sensitive to the extrinsic curvature of the string for finite momentum transfer. The characteristics of the diffractive peak in the differential elastic $pp$ scattering are affected by a small extrinsic curvature of the string.

  19. Computer Simulations Imply Forelimb-Dominated Underwater Flight in Plesiosaurs.

    Directory of Open Access Journals (Sweden)

    Shiqiu Liu

    2015-12-01

    Full Text Available Plesiosaurians are an extinct group of highly derived Mesozoic marine reptiles with a global distribution that spans 135 million years from the Early Jurassic to the Late Cretaceous. During their long evolutionary history they maintained a unique body plan with two pairs of large wing-like flippers, but their locomotion has been a topic of debate for almost 200 years. Key areas of controversy have concerned the most efficient biologically possible limb stroke, e.g. whether it consisted of rowing, underwater flight, or modified underwater flight, and how the four limbs moved in relation to each other: did they move in or out of phase? Previous studies have investigated plesiosaur swimming using a variety of methods, including skeletal analysis, human swimmers, and robotics. We adopt a novel approach using a digital, three-dimensional, articulated, free-swimming plesiosaur in a simulated fluid. We generated a large number of simulations under various joint degrees of freedom to investigate how the locomotory repertoire changes under different parameters. Within the biologically possible range of limb motion, the simulated plesiosaur swims primarily with its forelimbs using an unmodified underwater flight stroke, essentially the same as turtles and penguins. In contrast, the hindlimbs provide relatively weak thrust in all simulations. We conclude that plesiosaurs were forelimb-dominated swimmers that used their hind limbs mainly for maneuverability and stability.

  20. Development of forelimb bones in indigenous sheep fetuses

    Directory of Open Access Journals (Sweden)

    N. S. Ahmed

    2008-01-01

    Full Text Available The study included detection of the sites of ossification centers and their sequence of appearance in the forelimb bones of indigenous sheep fetuses by using double staining method with younger specimens and radiography or maceration methods with old specimens, as well as, histological study with some ages. The results showed that the primary ossification centers of the forelimb in indigenous sheep fetuses appeared firstly in the diaphyses of radius and ulna, humerus, scapula, metacarpus, phalanges and lastly in the carpal bone at an estimated age of 43, 45, 46, 47, 49 - 56 and 90-118 days old respectively. The results of statistical analysis of the total lengths of scapula, humerus, radius, ulna and metacarpus with the lengths of their ossified parts through the 7th – 15th weeks of fetus age, showed presence of significant differences in the average of these measurements among most of studied weeks. Also there was a significant differences in the average of relative increase in the total length and length of ossified part of diaphysis of studied bones during the 7th week in comparison to the same average in the other studied weeks (8th-15th week of indigenous sheep fetuses age.

  1. Body-weight distribution on forelimbs in rat tail-suspension model.

    Science.gov (United States)

    Sun, Lian-Wen; Wang, Chao; Xie, Tian; Pu, Fang; Sun, Yao; Fan, Yu-Bo

    2010-01-01

    To understand the tail-suspension model to simulate weightlessness better, this study was to investigate the relationship of the amount of body weight supported by forelimbs between the tilt angles of rat in the model. Normal rat had at least two basic postures. One was standing or walking, in which the forelimbs bear 44.6% of the body weight; the other one was resting, in which 23.9% of body weight was placed on the forelimbs. As for tail-suspended rat, body-weight distribution on forelimbs was linearly related to tilt angle. The linear relationship was y = -0.7423x + 70.849, R2 = 0.9269. The tilt angle should be approximately 35 degrees if normal standing load of 44.6% body weight was placed on the forelimbs. On the other hand, it should be approximately 63 degrees if normal resting load of 23.9% of body weight was placed on forelimbs. Furthermore, the body load on forelimbs in tail-suspension model became much larger if the period of different postures was considered. Therefore, it should be careful if forelimbs are used to be as convenient internal control in tail-suspended rats.

  2. Mechanisms of rotator cuff tendinopathy: intrinsic, extrinsic, or both?

    Science.gov (United States)

    Seitz, Amee L; McClure, Philip W; Finucane, Sheryl; Boardman, N Douglas; Michener, Lori A

    2011-01-01

    The etiology of rotator cuff tendinopathy is multi-factorial, and has been attributed to both extrinsic and intrinsic mechanisms. Extrinsic factors that encroach upon the subacromial space and contribute to bursal side compression of the rotator cuff tendons include anatomical variants of the acromion, alterations in scapular or humeral kinematics, postural abnormalities, rotator cuff and scapular muscle performance deficits, and decreased extensibility of pectoralis minor or posterior shoulder. A unique extrinsic mechanism, internal impingement, is attributed to compression of the posterior articular surface of the tendons between the humeral head and glenoid and is not related to subacromial space narrowing. Intrinsic factors that contribute to rotator cuff tendon degradation with tensile/shear overload include alterations in biology, mechanical properties, morphology, and vascularity. The varied nature of these mechanisms indicates that rotator cuff tendinopathy is not a homogenous entity, and thus may require different treatment interventions. Treatment aimed at addressing mechanistic factors appears to be beneficial for patients with rotator cuff tendinopathy, however, not for all patients. Classification of rotator cuff tendinopathy into subgroups based on underlying mechanism may improve treatment outcomes.

  3. Forelimb EMG-based trigger to control an electronic spinal bridge to enable hindlimb stepping after a complete spinal cord lesion in rats

    Directory of Open Access Journals (Sweden)

    Gad Parag

    2012-06-01

    Full Text Available Abstract Background A complete spinal cord transection results in loss of all supraspinal motor control below the level of the injury. The neural circuitry in the lumbosacral spinal cord, however, can generate locomotor patterns in the hindlimbs of rats and cats with the aid of motor training, epidural stimulation and/or administration of monoaminergic agonists. We hypothesized that there are patterns of EMG signals from the forelimbs during quadrupedal locomotion that uniquely represent a signal for the “intent” to step with the hindlimbs. These observations led us to determine whether this type of “indirect” volitional control of stepping can be achieved after a complete spinal cord injury. The objective of this study was to develop an electronic bridge across the lesion of the spinal cord to facilitate hindlimb stepping after a complete mid-thoracic spinal cord injury in adult rats. Methods We developed an electronic spinal bridge that can detect specific patterns of EMG activity from the forelimb muscles to initiate electrical-enabling motor control (eEmc of the lumbosacral spinal cord to enable quadrupedal stepping after a complete spinal cord transection in rats. A moving window detection algorithm was implemented in a small microprocessor to detect biceps brachii EMG activity bilaterally that then was used to initiate and terminate epidural stimulation in the lumbosacral spinal cord. We found dominant frequencies of 180–220 Hz in the EMG of the forelimb muscles during active periods, whereas these frequencies were between 0–10 Hz when the muscles were inactive. Results and conclusions Once the algorithm was validated to represent kinematically appropriate quadrupedal stepping, we observed that the algorithm could reliably detect, initiate, and facilitate stepping under different pharmacological conditions and at various treadmill speeds.

  4. Fitness, Extrinsic Complexity and Informing Science

    Directory of Open Access Journals (Sweden)

    Grandon Gill

    2017-03-01

    We raise concerns about society’s continuing investment in academic research that discounts the extrinsic complexity of the domains under study. Future Research We highlight a need for research to operationalize the concepts of fitness and complexity in practice.

  5. Forelimb preferences in human beings and other species: multiple models for testing hypotheses on lateralization

    Directory of Open Access Journals (Sweden)

    Elisabetta eVersace

    2015-03-01

    Full Text Available Consistent preferences in the use of right/left forelimbs are not exclusively present in humans. Functional asymmetries in forelimb use have been widely documented in a variety of vertebrate and invertebrate species. A matter of debate is whether non-human species exhibit a degree and consistency of functional forelimb asymmetries comparable to human handedness. The comparison is made difficult by the variability in hand use in humans and the few comparable studies conducted on other species. In spite of this, interesting continuities appear in functions such as feeding, object manipulation and communicative gestures. Studies on invertebrates show how widespread forelimb preferences are among animals, and the importance of experience for the development of forelimb asymmetries. Vertebrate species have been extensively investigated to clarify the origins of forelimb functional asymmetries: comparative evidence shows that selective pressures for different functions have likely driven the evolution of human handedness. Evidence of a complex genetic architecture of human handedness is in line with the idea of multiple evolutionary origins of this trait.

  6. Forelimbs of Tyrannosaurus Rex: A pathetic vestigial organ or an integral part of a fearsome predator?

    Science.gov (United States)

    Lee, Scott A.; Thomas, Joshua D.

    2014-12-01

    In this paper, we examine a first-year torque and angular acceleration problem to address a possible use of the forelimbs of Tyrannosaurus rex. A 1/40th-scale model (see Fig. 1) is brought to the classroom to introduce the students to the quandary: given that the forelimbs of T. rex were too short to reach its mouth, what function did the forelimbs serve? This issue crosses several scientific disciplines including paleontology, ecology, and physics, making it a great starting point for thinking "outside the box." Noted paleontologist Kenneth Carpenter has suggested that the forelimbs of T. rex were an integral part of its predatory behavior. Given the large teeth of T. rex, it is assumed that they killed with their teeth. Lipkin and Carpenter1 have suggested that the forelimbs were used to hold a struggling victim (which had not been dispatched with the first bite) while the final, lethal bite was applied. If that is the case, then the forelimbs must be capable of large angular accelerations α in order to grab the animal attempting to escape. The concepts of the typical first-year physics course are sufficient to test this hypothesis by solving α =τ /I . Naturally, students love solving any problem related to Tyrannosaurus rex!

  7. Comparative anatomy, homologies and evolution of the pectoral and forelimb musculature of tetrapods with special attention to extant limbed amphibians and reptiles.

    Science.gov (United States)

    Abdala, Virginia; Diogo, Rui

    2010-11-01

    The main aim of the present work is to synthesize the information obtained from our dissections of the pectoral and forelimb muscles of representative members of the major extant taxa of limbed amphibians and reptiles and from our review of the literature, in order to provide an account of the comparative anatomy, homologies and evolution of these muscles in the Tetrapoda. The pectoral and forelimb musculature of all these major taxa conform to a general pattern that seems to have been acquired very early in the evolutionary history of tetrapods. Although some muscles are missing in certain taxa, and a clear departure from this general pattern is obviously present in derived groups such as birds, the same overall configuration is easily distinguishable in these taxa. Among the most notable anatomical differences between the groups, one that seems to have relevant evolutionary and functional implications, concerns the distal insertion points of the forearm musculature. In tetrapods, the muscles of the radial and ulnar complexes of the forearm are pleisomorphically mainly inserted onto the radius/ulna or onto the more proximal carpal bones, but in mammals some of these muscles insert more distally onto bones such as the metacarpals. Interestingly, a similar trend towards a more distal insertion of these muscles is also found in some non-mammalian tetrapod taxa, such as some anurans (e.g. Phyllomedusa). This may be correlated with the acquisition of more subtle digital movement abilities in these latter taxa. © 2010 The Authors. Journal of Anatomy © 2010 Anatomical Society of Great Britain and Ireland.

  8. Muscle architecture of the common chimpanzee (Pan troglodytes): perspectives for investigating chimpanzee behavior.

    Science.gov (United States)

    Carlson, Kristian J

    2006-07-01

    Thorpe et al. (Am J Phys Anthropol 110:179-199, 1999) quantified chimpanzee (Pan troglodytes) muscle architecture and joint moment arms to determine whether they functionally compensated for structural differences between chimpanzees and humans. They observed enough distinction to conclude that musculoskeletal properties were not compensatory and suggested that chimpanzees and humans do not exhibit dynamically similar movements. These investigators based their assessment on unilateral limb musculatures from three male chimpanzees, of which they called one non-adult representative. Factors such as age, sex, and behavioral lateralization may be responsible for variation in chimpanzee muscle architecture, but this is presently unknown. While the full extent of variation in chimpanzee muscle architecture due to such factors cannot be evaluated with data presently available, the present study expands the chimpanzee dataset and provides a preliminary glimpse of the potential relevance of these factors. Thirty-seven forelimb and 36 hind limb muscles were assessed in two chimpanzee cadavers: one unilaterally (right limbs), and one bilaterally. Mass, fiber length, and physiological cross-sectional area (PCSA) are reported for individual muscles and muscle groups. The musculature of an adult female is more similar in architectural patterns to a young male chimpanzee than to humans, particularly when comparing muscle groups. Age- and sex-related intraspecific differences do not obscure chimpanzee-human interspecific differences. Side asymmetry in one chimpanzee, despite consistent forelimb directional asymmetry, also does not exceed the magnitude of chimpanzee-human differences. Left forelimb muscles, on average, usually had higher masses and longer fiber lengths than right, while right forelimb muscles, on average, usually had greater PCSAs than left. Most muscle groups from the left forelimb exhibited greater masses than right groups, but group asymmetry was significant

  9. Bimanual motor coordination controlled by cooperative interactions in intrinsic and extrinsic coordinates.

    Science.gov (United States)

    Sakurada, Takeshi; Ito, Koji; Gomi, Hiroaki

    2016-01-01

    Although strong motor coordination in intrinsic muscle coordinates has frequently been reported for bimanual movements, coordination in extrinsic visual coordinates is also crucial in various bimanual tasks. To explore the bimanual coordination mechanisms in terms of the frame of reference, here we characterized implicit bilateral interactions in visuomotor tasks. Visual perturbations (finger-cursor gain change) were applied while participants performed a rhythmic tracking task with both index fingers under an in-phase or anti-phase relationship in extrinsic coordinates. When they corrected the right finger's amplitude, the left finger's amplitude unintentionally also changed [motor interference (MI)], despite the instruction to keep its amplitude constant. Notably, we observed two specificities: one was large MI and low relative-phase variability (PV) under the intrinsic in-phase condition, and the other was large MI and high PV under the extrinsic in-phase condition. Additionally, using a multiple-interaction model, we successfully decomposed MI into intrinsic components caused by motor correction and extrinsic components caused by visual-cursor mismatch of the right finger's movements. This analysis revealed that the central nervous system facilitates MI by combining intrinsic and extrinsic components in the condition with in-phases in both intrinsic and extrinsic coordinates, and that under-additivity of the effects is explained by the brain's preference for the intrinsic interaction over extrinsic interaction. In contrast, the PV was significantly correlated with the intrinsic component, suggesting that the intrinsic interaction dominantly contributed to bimanual movement stabilization. The inconsistent features of MI and PV suggest that the central nervous system regulates multiple levels of bilateral interactions for various bimanual tasks.

  10. Cortical field potentials preceding self-paced forelimb movements and influences of cerebellectomy upon them in rats.

    Science.gov (United States)

    Ohishi, Hiroko; Ichikawa, Jun; Matsuzaki, Ryuichi; Kyuhou, Shin ichi; Matsuura-Nakao, Kazuko; Seki, Tomomi; Gemba, Hisae

    2003-11-27

    Seven rats were well trained to move lever to the left by right forelimb at self-pace (self-paced forelimb movements). Cortical field potentials associated with self-paced forelimb movements were recorded by electrodes implanted chronically on the surface and at a 2.0 mm depth in the forelimb motor cortex on the left side. A surface-negative, depth-positive potential starting about 1.0 s prior to the movement was recorded in the rostral part of the forelimb motor cortex. Further we found that the premovement potential was eliminated by the cerebellar hemispherectomy on the right side. This suggests the participation of the cerebellar hemisphere in preparing the activity of the motor cortex before self-paced forelimb movements in rats, by cerebello-thalamo-cortical projections.

  11. Facial Mechanosensory Influence on Forelimb Movement in Newborn Opossums, Monodelphis domestica.

    Directory of Open Access Journals (Sweden)

    Marie-Josée Desmarais

    Full Text Available The opossum, Monodelphis domestica, is born very immature but crawls, unaided, with its forelimbs (FL from the mother's birth canal to a nipple where it attaches to pursue its development. What sensory cues guide the newborn to the nipple and trigger its attachment to it? Previous experiments showed that low intensity electrical stimulation of the trigeminal ganglion induces FL movement in in vitro preparations and that trigeminal innervation of the facial skin is well developed in the newborn. The skin does not contain Vater-Pacini or Meissner touch corpuscles at this age, but it contains cells which appear to be Merkel cells (MC. We sought to determine if touch perceived by MC could exert an influence on FL movements. Application of the fluorescent dye AM1-43, which labels sensory cells such as MC, revealed the presence of a large number of labeled cells in the facial epidermis, especially in the snout skin, in newborn opossums. Moreover, calibrated pressure applied to the snout induced bilateral and simultaneous electromyographic responses of the triceps muscle in in vitro preparations of the neuraxis and FL from newborn. These responses increase with stimulation intensity and tend to decrease over time. Removing the facial skin nearly abolished these responses. Metabotropic glutamate 1 receptors being involved in MC neurotransmission, an antagonist of these receptors was applied to the bath, which decreased the EMG responses in a reversible manner. Likewise, bath application of the purinergic type 2 receptors, used by AM1-43 to penetrate sensory cells, also decreased the triceps EMG responses. The combined results support a strong influence of facial mechanosensation on FL movement in newborn opossums, and suggest that this influence could be exerted via MC.

  12. Encoding of Forelimb Forcesby Corticospinal Tract Activity in the Rat

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    Yi eGuo

    2014-05-01

    Full Text Available In search of a solution to the long standing problems encountered in traditional brain computer interfaces (BCI, the lateral descending tracts of the spinal cord present an alternative site for taping into the volitional motor signals. Due to the convergence of the cortical outputs into a final common pathway in the descending tracts of the spinal cord, neural interfaces with the spinal cord can potentially acquire signals richer with volitional information in a smaller anatomical region. The main objective of this study was to evaluate the feasibility of extracting motor control signals from the corticospinal tract (CST of the rat spinal cord. Flexible substrate, multi-electrode arrays (MEA were implanted in the CST of rats trained for a lever pressing task. This novel use of flexible substrate MEAs allowed recording of CST activity in behaving animals for up to three weeks with the current implantation technique. Time-frequency and principal component analyses (PCA were applied to the neural signals to reconstruct isometric forelimb forces. Computed regression coefficients were then used to predict isometric forces in additional trials. The correlation between measured and predicted forces in the vertical direction averaged across six animals was 0.67 and R-squared value was 0.44. Force regression in the horizontal directions was less successful, possibly due to the small amplitude of forces. Neural signals above and near the high gamma band made the largest contributions to prediction of forces. The results of this study support the feasibility of a spinal cord computer interface (SCCI for generation of command signals in paralyzed individuals.

  13. Extrinsic curvature induced 2-d gravity

    CERN Document Server

    Viswanathan, K S

    1993-01-01

    Abtract: 2-dimensional fermions are coupled to extrinsic geometry of a conformally immersed surface in ${\\bf R}^3$ through gauge coupling. By integrating out the fermions, we obtain a WZNW action involving extrinsic curvature of the surface. Restricting the resulting effective action to surfaces of $h\\sqrt g=1$, an explicit form of the action invariant under Virasaro symmetry is obtained. This action is a sum of the geometric action for the Virasaro group and the light-cone action of 2-d gravity plus an interaction term. The central charges of the theory in both the left and right sectors are calculated.

  14. Intrinsic and Extrinsic Motivation among Collegiate Instrumentalists

    Science.gov (United States)

    Diaz, Frank M.

    2010-01-01

    The purpose of this study was to gather and compare information on measures of intrinsic and extrinsic motivation among instrumentalists enrolled in collegiate ensembles. A survey instrument was developed to gather information concerning demographic data and responses to questions on motivational preference. Participants were undergraduate and…

  15. Intrinsic and Extrinsic Motivation among Collegiate Instrumentalists

    Science.gov (United States)

    Diaz, Frank M.

    2010-01-01

    The purpose of this study was to gather and compare information on measures of intrinsic and extrinsic motivation among instrumentalists enrolled in collegiate ensembles. A survey instrument was developed to gather information concerning demographic data and responses to questions on motivational preference. Participants were undergraduate and…

  16. Encouraging Classroom Participation with Empty Extrinsic Rewards

    Science.gov (United States)

    Guinee, William

    2012-01-01

    In this article, the author talks about how to encourage classroom participation with empty extrinsic rewards. He uses "bonus points" in awarding students for particularly interesting or well thought-out contributions to the class discussion. These bonus points have absolutely no effect on the student's course grade. But the students respond…

  17. Intrinsic and extrinsic factors influencing large African herbivore movements

    NARCIS (Netherlands)

    Venter, J.A.; Prins, H.H.T.; Mashanova, A.; Boer, de W.F.; Slotow, R.

    2015-01-01

    Understanding environmental as well as anthropogenic factors that influence large herbivore ecological patterns and processes should underpin their conservation and management. We assessed the influence of intrinsic, extrinsic environmental and extrinsic anthropogenic factors on movement behaviour o

  18. Effects of Extrinsic Rewards on Intrinsic Motivation in the Classroom.

    Science.gov (United States)

    Workman, Edward A.; Williams, Robert L.

    1980-01-01

    Reviews classroom behavior management studies to see if extrinsic rewards affect intrinsic reinforcement value of appropriate classroom behaviors. Conclusion indicates extrinsic rewards are useful. Teachers need not avoid the use of rewards in fear of undermining intrinsic interest. (LAB)

  19. Effects of Extrinsic Rewards on Intrinsic Motivation in the Classroom.

    Science.gov (United States)

    Workman, Edward A.; Williams, Robert L.

    1980-01-01

    Reviews classroom behavior management studies to see if extrinsic rewards affect intrinsic reinforcement value of appropriate classroom behaviors. Conclusion indicates extrinsic rewards are useful. Teachers need not avoid the use of rewards in fear of undermining intrinsic interest. (LAB)

  20. Sensory feedback alters spontaneous limb movements in newborn rats: effects of unilateral forelimb weighting.

    Science.gov (United States)

    Brumley, Michele R; Robinson, Scott R

    2013-05-01

    Perinatal mammals show spontaneous movements that often appear random and uncoordinated. Here, we examined if spontaneous limb movements are responsive to a proprioceptive manipulation by applying a weight unilaterally to a forelimb of postnatal day 0 (P0; day of birth) and P1 rats. Weights were calibrated to approximate 0%, 25%, 50%, or 100% of the average mass of a forelimb, and were attached at the wrist. P0 and P1 pups showed different levels of activity during the period of limb weighting, in response to weight removal, and during the period after weighting. Pups exposed to 50% and 100% weights showed proportionately more activity in the nonweighted forelimb during the period of weighting, suggesting a threshold for evoking proprioceptive changes. Findings suggest that newborn rats use movement-related feedback to modulate spontaneous motor activity, and corroborate studies of human infants that have suggested a role for proprioception during early motor development.

  1. Distinguishing subtypes of extrinsic motivation among people with mild to borderline intellectual disability : Distinguishing subtypes of extrinsic motivation

    NARCIS (Netherlands)

    Frielink, N.; Schuengel, C.; Embregts, P.J.C.M.

    Background According to self-determination theory, motivation is ordered in types, including amotivation, extrinsic motivation and intrinsic motivation. Self-determination theory defines four subtypes of extrinsic motivation: external motivation, introjected motivation, identified motivation and

  2. Early onset of forced impaired forelimb use causes recovery of forelimb skilled motor function but no effect on gross sensory-motor function after capsular hemorrhage in rats.

    Science.gov (United States)

    Ishida, Akimasa; Tamakoshi, Keigo; Hamakawa, Michiru; Shimada, Haruka; Nakashima, Hiroki; Masuda, Tadashi; Hida, Hideki; Ishida, Kazuto

    2011-11-20

    Intensive use of the impaired forelimb promotes behavioral recovery and induces plastic changes of the central nervous system after stroke. However, the optimal onset of intensive use treatment after stroke is controversial. In this study, we investigated whether early forced impaired limb use (FLU) initiated 24h after intracerebral hemorrhage (ICH) of the internal capsule affected behavioral recovery and histological damage. Rats were subjected to ICH via low-dose collagenase infusion or sham stroke. One day after surgery, the ipsilateral forelimbs of half of the ICH and sham rats were casted for a week to induce the use of their contralateral forelimbs. Behavioral assessments were performed on days 10-12 and 26-28 after the surgery and followed by histological assessments. Improvements in skilled reaching and coordinated stepping function were found in the FLU-treated group in comparison with the untreated group after ICH. Additionally, FLU-treated ICH animals showed more normal and precise reaching and stepping movements as compared with ICH control animals. In contrast, FLU did not have a significant impact on gross sensory-motor functions such as the motor deficit score, contact placing response and spontaneous usage of the impaired paw. The volume of tissue lost and the number of spared corticospinal neurons in lesioned motor cortex were not affected by early FLU after ICH. These findings demonstrate the efficacy of early focused use of an impaired limb after internal capsule hemorrhage.

  3. Extrinsic and intrinsic curvatures in thermodynamic geometry

    Energy Technology Data Exchange (ETDEWEB)

    Hosseini Mansoori, Seyed Ali, E-mail: shossein@bu.edu [Department of Physics, Boston University, 590 Commonwealth Ave., Boston, MA 02215 (United States); Department of Physics, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Mirza, Behrouz, E-mail: b.mirza@cc.iut.ac.ir [Department of Physics, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Sharifian, Elham, E-mail: e.sharifian@ph.iut.ac.ir [Department of Physics, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of)

    2016-08-10

    We investigate the intrinsic and extrinsic curvatures of a certain hypersurface in thermodynamic geometry of a physical system and show that they contain useful thermodynamic information. For an anti-Reissner–Nordström-(A)de Sitter black hole (Phantom), the extrinsic curvature of a constant Q hypersurface has the same sign as the heat capacity around the phase transition points. The intrinsic curvature of the hypersurface can also be divergent at the critical points but has no information about the sign of the heat capacity. Our study explains the consistent relationship holding between the thermodynamic geometry of the KN-AdS black holes and those of the RN (J-zero hypersurface) and Kerr black holes (Q-zero hypersurface) ones [1]. This approach can easily be generalized to an arbitrary thermodynamic system.

  4. Extrinsic allergic alveolitis in Scottish maltworkers.

    Science.gov (United States)

    Grant, I W; Blackadder, E S; Greenberg, M; Blyth, W

    1976-01-01

    In a survey of respiratory disease in the Scottish malting industry 5.2% of employees were found to have symptoms of extrinsic allergic alveolitis. In most cases the disease was mild and not associated with any serious respiratory disability. It was significantly less common where modern mechanical methods of malting were used. Mycological and serological studies suggested that it was usually caused by a type 3 allergic reaction to Aspergillus clavatus. PMID:1252813

  5. Intrinsic-extrinsic factors in sport motivation.

    Science.gov (United States)

    Pedersen, Darhl M

    2002-10-01

    Participants were 83 students (36 men and 47 women). 10 intrinsic-extrinsic factors involved in sport motivation were obtained. The factors were generated from items obtained from the participants rather than items from the experimenter. This was done to avoid the possible influence of preconceptions on the part of the experimenter regarding what the final dimensions may be. Obtained motivational factors were Social Reinforcement, Fringe Benefits, Fame and Fortune, External Forces, Proving Oneself, Social Benefits, Mental Enrichment, Expression of Self, Sense of Accomplishment, and Self-enhancement. Each factor was referred to an intrinsic-extrinsic dimension to describe its relative position on that dimension. The order of the factors as listed indicates increasing intrinsic motivation. i.e., the first four factors were rated in the extrinsic range, whereas the remaining six were rated to be in the intrinsic range. Next, the participants rated the extent to which each of the various factors was involved in their decision to participate in sport activities. The pattern of use of the motivational factors was the same for both sexes except that men indicated greater use of the Fringe Benefits factor. Overall, the more intrinsic a sport motivation factor was rated, the more likely it was to be rated as a factor in actual sport participation.

  6. Kinetics of the forelimb in horses circling on different ground surfaces at the trot.

    Science.gov (United States)

    Chateau, Henry; Camus, Mathieu; Holden-Douilly, Laurène; Falala, Sylvain; Ravary, Bérangère; Vergari, Claudio; Lepley, Justine; Denoix, Jean-Marie; Pourcelot, Philippe; Crevier-Denoix, Nathalie

    2013-12-01

    Circling increases the expression of distal forelimb lameness in the horse, depending on rein, diameter and surface properties of the circle. However, there is limited information about the kinetics of horses trotting on circles. The aim of this study was to quantify ground reaction force (GRF) and moments in the inside and outside forelimb of horses trotting on circles and to compare the results obtained on different ground surfaces. The right front hoof of six horses was equipped with a dynamometric horseshoe, allowing the measurement of 3-dimensional GRF, moments and trajectory of the centre of pressure. The horses were lunged at slow trot (3 m/s) on right and left 4 m radius circles on asphalt and on a fibre sand surface. During circling, the inside forelimb produced a smaller peak vertical force and the stance phase was longer in comparison with the outside forelimb. Both right and left circling produced a substantial transversal force directed outwards. On a soft surface (sand fibre), the peak transversal force and moments around the longitudinal and vertical axes of the hoof were significantly decreased in comparison with a hard surface (asphalt). Sinking of the lateral or medial part of the hoof in a more compliant surface enables reallocation of part of the transversal force into a proximo-distal force, aligned with the limb axis, thus limiting extrasagittal stress on the joints.

  7. Rapid functional reorganization of the forelimb cortical representation after thoracic spinal cord injury in adult rats.

    Science.gov (United States)

    Sydekum, Esther; Ghosh, Arko; Gullo, Miriam; Baltes, Christof; Schwab, Martin; Rudin, Markus

    2014-02-15

    Thoracic spinal cord injured rats rely largely on forelimbs to walk, as their hindlimbs are dysfunctional. This increased limb use is accompanied by expansion of the cortical forelimb sensory representation. It is unclear how quickly the representational changes occur and whether they are at all related to the behavioral adaptation. Using blood oxygenation level dependent functional mangetic resonance imaging (BOLD-fMRI) we show that major plastic changes of the somato-sensory map can occur as early as one day after injury. The extent of map increase was variable between animals, and some animals showed a reduction in map size. However, at three or seven days after injury a significant enhancement of the forelimb representation was evident in all the animals. In a behavioral test for precise limb control, crossing of a horizontal ladder, the injured rats relied almost entirely on their forelimbs; they initially made more mistakes than at 7 days post injury. Remarkably, in the individual animals the behavioral performance seen at seven days was proportional to the physiological change present at one day after injury. The rapid increase in cortical representation of the injury-spared body part may provide the additional neural substrate necessary for high level behavioral adaptation.

  8. Hox C6 expression during development and regeneration of forelimbs in larval Notophthalmus viridescens.

    Science.gov (United States)

    Khan, P A; Tsilfidis, C; Liversage, R A

    1999-06-01

    A central theme concerning the epimorphic regenerative potential of urodele amphibian appendages is that limb regeneration in the adult parallels larval limb development. Results of previous research have led to the suggestion that homeobox containing genes are "re-expressed" during the epimorphic regeneration of forelimbs of adult Notophthalmus viridescens in patterns which retrace larval limb development. However, to date no literature exists concerning expression patterns of any homeobox containing genes during larval development of this species. The lack of such information has been a hindrance in exploring the similarities as well as differences which exist between limb regeneration in adults and limb development in larvae. Here we report the first such results of the localization of Hox C6 (formerly, NvHBox-1) in developing and regenerating forelimbs of N. viridescens larvae as demonstrated by whole-mount in situ hybridization. Inasmuch as the pattern of Hox C6 expression is similar in developing forelimb buds of larvae and epimorphically regenerating forelimb blastemata of both adults and larvae, our results support the paradigm that epimorphic regeneration in adult newts parallels larval forelimb development. However, in contrast with observations which document the presence of Hox C6 in both intact, as well as regenerating hindlimbs and tails of adult newts, our results reveal no such Hox C6 expression during larval development of hindlimbs or the tail. As such, our findings indicate that critical differences in larval hindlimb and tail development versus adult expression patterns of this gene in these two appendages may be due primarily to differences in gene regulation as opposed to gene function. Thus, the apparent ability of urodeles to regulate genes in such a highly co-ordinated fashion so as to replace lost, differentiated, appendicular structures in adult animals may assist, at least in part, in better elucidating the phenomenon of epimorphic

  9. Three-dimensional visualisation of the internal anatomy of the sparrowhawk (Accipiter nisus) forelimb using contrast-enhanced micro-computed tomography.

    Science.gov (United States)

    Bribiesca-Contreras, Fernanda; Sellers, William I

    2017-01-01

    Gross dissection is a widespread method for studying animal anatomy, despite being highly destructive and time-consuming. X-ray computed tomography (CT) has been shown to be a non-destructive alternative for studying anatomical structures. However, in the past it has been limited to only being able to visualise mineralised tissues. In recent years, morphologists have started to use traditional X-ray contrast agents to allow the visualisation of soft tissue elements in the CT context. The aim of this project is to assess the ability of contrast-enhanced micro-CT (μCT) to construct a three-dimensional (3D) model of the musculoskeletal system of the bird wing and to quantify muscle geometry and any systematic changes due to shrinkage. We expect that this reconstruction can be used as an anatomical guide to the sparrowhawk wing musculature and form the basis of further biomechanical analysis of flight. A 3% iodine-buffered formalin solution with a 25-day staining period was used to visualise the wing myology of the sparrowhawk (Accipiter nisus). μCT scans of the wing were taken over the staining period until full penetration of the forelimb musculature by iodine was reached. A 3D model was reconstructed by manually segmenting out the individual elements of the avian wing using 3D visualisation software. Different patterns of contrast were observed over the duration of the staining treatment with the best results occurring after 25 days of staining. Staining made it possible to visualise and identify different elements of the soft tissue of the wing. Finally, a 3D reconstruction of the musculoskeletal system of the sparrowhawk wing is presented and numerical data of muscle geometry is compared to values obtained by dissection. Contrast-enhanced μCT allows the visualisation and identification of the wing myology of birds, including the smaller muscles in the hand, and provides a non-destructive way for quantifying muscle volume with an accuracy of 96.2%. By combining

  10. Three-dimensional visualisation of the internal anatomy of the sparrowhawk (Accipiter nisus forelimb using contrast-enhanced micro-computed tomography

    Directory of Open Access Journals (Sweden)

    Fernanda Bribiesca-Contreras

    2017-03-01

    Full Text Available Background Gross dissection is a widespread method for studying animal anatomy, despite being highly destructive and time-consuming. X-ray computed tomography (CT has been shown to be a non-destructive alternative for studying anatomical structures. However, in the past it has been limited to only being able to visualise mineralised tissues. In recent years, morphologists have started to use traditional X-ray contrast agents to allow the visualisation of soft tissue elements in the CT context. The aim of this project is to assess the ability of contrast-enhanced micro-CT (μCT to construct a three-dimensional (3D model of the musculoskeletal system of the bird wing and to quantify muscle geometry and any systematic changes due to shrinkage. We expect that this reconstruction can be used as an anatomical guide to the sparrowhawk wing musculature and form the basis of further biomechanical analysis of flight. Methods A 3% iodine-buffered formalin solution with a 25-day staining period was used to visualise the wing myology of the sparrowhawk (Accipiter nisus. μCT scans of the wing were taken over the staining period until full penetration of the forelimb musculature by iodine was reached. A 3D model was reconstructed by manually segmenting out the individual elements of the avian wing using 3D visualisation software. Results Different patterns of contrast were observed over the duration of the staining treatment with the best results occurring after 25 days of staining. Staining made it possible to visualise and identify different elements of the soft tissue of the wing. Finally, a 3D reconstruction of the musculoskeletal system of the sparrowhawk wing is presented and numerical data of muscle geometry is compared to values obtained by dissection. Discussion Contrast-enhanced μCT allows the visualisation and identification of the wing myology of birds, including the smaller muscles in the hand, and provides a non-destructive way for quantifying

  11. Forelimb Kinematics of Rats Using XROMM, with Implications for Small Eutherians and Their Fossil Relatives.

    Directory of Open Access Journals (Sweden)

    Matthew F Bonnan

    Full Text Available The earliest eutherian mammals were small-bodied locomotor generalists with a forelimb morphology that strongly resembles that of extant rats. Understanding the kinematics of the humerus, radius, and ulna of extant rats can inform and constrain hypotheses concerning typical posture and mobility in early eutherian forelimbs. The locomotion of Rattus norvegicus has been extensively studied, but the three-dimensional kinematics of the bones themselves remains under-explored. Here, for the first time, we use markerless XROMM (Scientific Rotoscoping to explore the three-dimensional long bone movements in Rattus norvegicus during a normal, symmetrical gait (walking. Our data show a basic kinematic profile that agrees with previous studies on rats and other small therians: rats maintain a crouched forelimb posture throughout the step cycle, and the ulna is confined to flexion/extension in a parasagittal plane. However, our three-dimensional data illuminate long-axis rotation (LAR movements for both the humerus and the radius for the first time. Medial LAR of the humerus throughout stance maintains an adducted elbow with a caudally-facing olecranon process, which in turn maintains a cranially-directed manus orientation (pronation. The radius also shows significant LAR correlated with manus pronation and supination. Moreover, we report that elbow flexion and manus orientation are correlated in R. norvegicus: as the elbow angle becomes more acute, manus supination increases. Our data also suggest that manus pronation and orientation in R. norvegicus rely on a divided system of labor between the ulna and radius. Given that the radius follows the flexion and extension trajectory of the ulna, it must rotate at the elbow (on the capitulum so that during the stance phase its distal end lies medial to ulna, ensuring that the manus remains pronated while the forelimb is supporting the body. We suggest that forelimb posture and kinematics in Juramaia, Eomaia, and

  12. Forelimb preferences in quadrupedal marsupials and their implications for laterality evolution in mammals.

    Science.gov (United States)

    Giljov, Andrey; Karenina, Karina; Malashichev, Yegor

    2013-03-06

    Acquisition of upright posture in evolution has been argued to facilitate manual laterality in primates. Owing to the high variety of postural habits marsupials can serve as a suitable model to test whether the species-typical body posture shapes forelimb preferences in non-primates or this phenomenon emerged only in the course of primate evolution. In the present study we aimed to explore manual laterality in marsupial quadrupeds and compare them with the results in the previously studied bipedal species. Forelimb preferences were assessed in captive grey short-tailed opossum (Monodelphis domestica) and sugar glider (Petaurus breviceps) in four different types of unimanual behaviour per species, which was not artificially evoked. We examined the possible effects of sex, age and task, because these factors have been reported to affect motor laterality in placental mammals. In both species the direction of forelimb preferences was strongly sex-related. Male grey short-tailed opossums showed right-forelimb preference in most of the observed unimanual behaviours, while male sugar gliders displayed only a slight, not significant rightward tendency. In contrast, females in both species exhibited consistent group-level preference of the left forelimb. We failed to reveal significant differences in manual preferences between tasks of potentially differing complexity: reaching a stable food item and catching live insects, as well as between the body support and food manipulation. No influence of subjects' age on limb preferences was found. The direction of sex-related differences in the manual preferences found in quadrupedal marsupials seems to be not typical for placental mammals. We suggest that the alternative way of interhemispheric connection in absence of corpus callosum may result in a fundamentally distinct mechanism of sex effect on limb preferences in marsupials compared to placentals. Our data confirm the idea that non-primate mammals differ from primates in

  13. [Recent advances in extrinsic allergic alveolitis].

    Science.gov (United States)

    Sennekamp, J; Joest, M

    2008-01-01

    Extrinsic allergic alveolitis (hypersensitivity pneumonitis), especially humidifier lung, has been more frequently diagnosed over the last decades, whereas farmer's lung has decreased over the same time period. Today two types of the chronic course of extrinsic allergic alveolitis can be distinguished. The recurrent chronic course with a good prognosis may be differentiated from the insidious course with a poor prognosis by means of different histological patterns (UIP, NSIP, BOOP pattern). The characteristic neutrophilic infiltration of the lung in the insidious course cannot be detected by bronchoalveolar lavage (BAL) methods. Furthermore, lymphocytosis in the BAL can be absent or present at a low level. The CD4/CD8 ratio is not always decreased and may be normal or even increased in these insidious cases with a poor prognosis. Granulomas in the lung tissue, however, point to a good prognosis. In the diagnostic work-up of machine operator's and humidifier lung, it is advisable not only to look for serum antibodies against bacteria and molds but also for rapid growing mycobacteria in a sample of machine or humidifier water. IgM and IgG rheumatoid factors occur frequently in allergic alveolitis, especially in humidifier lung. The patients, however, do not suffer from arthritis. The IgM rheumatoid factor may simulate IgM antibodies against numerous infectious agents (e. g., Bordetella pertussis or Mycoplasma pneumoniae). Taking this phenomenon into account may improve the current differential diagnosis of allergic alveolitis.

  14. Evolving extrinsic curvature and the cosmological constant problem

    Science.gov (United States)

    Capistrano, Abraão J. S.; Cabral, Luis A.

    2016-10-01

    The concept of smooth deformation of Riemannian manifolds associated with the extrinsic curvature is explained and applied to the Friedmann-Lemaître-Robertson-Walker cosmology. We show that such deformation can be derived from the Einstein-Hilbert-like dynamical principle may produce an observable effect in the sense of Noether. As a result, we show how the extrinsic curvature compensates both quantitative and qualitative differences between the cosmological constant Λ and the vacuum energy {ρ }{vac} obtaining the observed upper bound for the cosmological constant problem at electroweak scale. The topological characteristics of the extrinsic curvature are discussed showing that the produced extrinsic scalar curvature is an evolving dynamical quantity.

  15. Is the left forelimb preference indicative of a stressful situation in horses?

    Science.gov (United States)

    Siniscalchi, M; Padalino, B; Lusito, R; Quaranta, A

    2014-09-01

    Evidence for behavioural and brain lateralisation is now widespread among the animal kingdom; lateralisation of limb use (pawedness) occurs in several mammals including both feral and domestic horses. We investigated limb preferences in 14 Quarter Horse during different motor tasks (walking, stepping on and off a step, truck loading and unloading). Population lateralisation was observed in two tasks: horses preferentially used their left forelimb during truck loading and stepping off a step. The results also revealed that horses showed higher scores for anxious behaviours during truck loading suggesting that the use of the left forelimb in this task may reflect the main role of the right hemisphere in control of behaviour during stressful situation.

  16. The transformation suppressor gene Reck is required for postaxial patterning in mouse forelimbs

    Directory of Open Access Journals (Sweden)

    Mako Yamamoto

    2012-03-01

    The membrane-anchored metalloproteinase-regulator RECK has been characterized as a tumor suppressor. Here we report that mice with reduced Reck-expression show limb abnormalities including right-dominant, forelimb-specific defects in postaxial skeletal elements. The forelimb buds of low-Reck mutants have an altered dorsal ectoderm with reduced Wnt7a and Igf2 expression, and hypotrophy in two signaling centers (i.e., ZPA and AER that are essential for limb outgrowth and patterning. Reck is abundantly expressed in the anterior mesenchyme in normal limb buds; mesenchyme-specific Reck inactivation recapitulates the low-Reck phenotype; and some teratogens downregulate Reck in mesenchymal cells. Our findings illustrate a role for Reck in the mesenchymal-epithelial interactions essential for mammalian development.

  17. A robotic platform to assess, guide and perturb rat forelimb movements

    OpenAIRE

    Vigaru, Bogdan C; Lambercy, Olivier; Schubring-Giese, Maximilian; Hosp, Jonas A; Schneider, Melanie; Osei-Atiemo, Clement; Andreas R. Luft; Gassert, Roger

    2013-01-01

    Animal models are widely used to explore the mechanisms underlying sensorimotor control and learning. However, current experimental paradigms allow only limited control over task difficulty and cannot provide detailed information on forelimb kinematics and dynamics. Here we propose a novel robotic device for use in motor learning investigations with rats. The compact, highly transparent, three degree-of-freedom manipulandum is capable of rendering nominal forces of 2 N to guide or perturb rat...

  18. Cineradiographic study of forelimb movements during quadrupedal walking in the brown lemur (Eulemur fulvus, Primates: Lemuridae).

    Science.gov (United States)

    Schmidt, M; Fischer, M S

    2000-02-01

    Movements of forelimb joints and segments during walking in the brown lemur (Eulemur fulvus) were analyzed using cineradiography (150 frames/sec). Metric gait parameters, forelimb kinematics, and intralimb coordination are described. Calculation of contribution of segment displacements to stance propulsion shows that scapular retroversion in a fulcrum near the vertebral border causes more than 60% of propulsion. The contribution by the shoulder joint is 30%, elbow joint 5%, and wrist joint 1%. Correlation analysis was applied to reveal the interdependency between metric and kinematic parameters. Only the effective angular movement of the elbow joint during stance is speed-dependent. Movements of all other forelimb joints and segments are independent of speed and influence, mainly, linear gait parameters (stride length, stance length). Perhaps the most important result is the hitherto unknown and unexpected degree of scapular mobility. Scapular movements consist of ante-/retroversion, adduction/abduction, and scapular rotation about the longitudinal axis. Inside rotation of the scapula (60 degrees -70 degrees ), together with flexion in the shoulder joint, mediates abduction of the humerus, which is not achieved in the shoulder joint, and is therefore strikingly different from humeral abduction in man. Movements of the shoulder joint are restricted to flexion and extension. At touch down, the shoulder joint of the brown lemur is more extended compared to that of other small mammals. The relatively long humerus and forearm, characteristic for primates, are thus effectively converted into stride length. Observed asymmetries in metric and kinematic behavior of the left and right forelimb are caused by an unequal lateral bending of the spinal column.

  19. Angiographic aspect of the distal forelimb in donkeys (Equus asinus used for animal traction

    Directory of Open Access Journals (Sweden)

    Maria Angélica Miglino

    2009-12-01

    Full Text Available The asinine species was originated thousands of years ago from the same branch of domestic equine. Asinines have been undergoing a great adaptation resulting in different characteristics observed in their populations around the world. In the northeastern region of Brazil, they play an essential role in the economy of local families. Due to a large number of locomotor disorders and a lack of professional care for these animals, a radiographic study of the distal forelimb region of the asinine was carried out in order to gather information for the improvement of clinical and surgical practices in this species, and to explain their low susceptibility to locomotor disorders compared to that of the domestic equine. The angiographic examination revealed the main arterial vessels committed to the blood supply of the forelimbs in these animals, providing evidence of the vascular pattern of the median and palmar common digital arteries, which originated a great number of collateral branches, mainly to the distal phalanx. The distal forelimbs in donkeys have shown great vascular anastomosis, promoting additional blood supply to the deep endosteum and periosteum regions, probably as a response to the physical activity developed by these animals.

  20. In vivo optogenetic tracing of functional corticocortical connections between motor forelimb areas

    Directory of Open Access Journals (Sweden)

    Riichiro eHira

    2013-04-01

    Full Text Available Interactions between distinct motor cortical areas are essential for coordinated motor behaviors. In rodents, the motor cortical forelimb areas are divided into at least two distinct areas: the rostral forelimb area (RFA and the caudal forelimb area (CFA. The RFA is thought to be an equivalent of the premotor cortex in primates, whereas the CFA is believed to be an equivalent of the primary motor cortex. Although reciprocal connections between the RFA and the CFA have been anatomically identified in rats, it is unknown whether there are functional connections between these areas that can induce postsynaptic spikes. In this study, we used an in vivo Channelrhodopsin-2 photostimulation method to trace the functional connections between the mouse RFA and CFA. Simultaneous electrical recordings were utilized to detect spiking activities induced by synaptic inputs originating from photostimulated areas. This method, in combination with anatomical tracing, demonstrated that the RFA receives strong functional projections from layer 2/3 and/or layer 5a, but not from layer 5b, of the CFA. Further, the CFA receives strong projections from layer 5b neurons of the RFA. The onset latency of electrical responses evoked in remote areas upon photostimulation of the other areas was approximately 10 ms, which is consistent with the synaptic connectivity between these areas. Our results suggest that neuronal activities in the RFA and the CFA during movements are formed through asymmetric reciprocal connections.

  1. Extrinsic allergic alveolitis caused by misting fountains.

    Science.gov (United States)

    Koschel, Dirk; Stark, Wolfram; Karmann, Fritz; Sennekamp, Jochen; Müller-Wening, Dietrich

    2005-08-01

    Recently, an increasing number of patients were presented to our clinics with febrile and respiratory symptoms associated with exposure to a new type of domestic ultrasonic humidifier. We report on 11 patients who developed recurrent episodes of fever, cough and dyspnea after repeated exposure to ultrasonic misting fountains at home. A diagnosis of extrinsic allergic alveolitis (EAA) or toxic alveolitis was made on the basis of the history and the clinical, radiological, laboratory and immunological findings. Eight patients were subjected to inhalative challenge tests with their own ultrasonic misting fountains, and all of them exhibited positive reactions. Nine patients were diagnosed with an EAA (humidifier lung) and two patients with a toxic alveolitis (humidifier fever). This study demonstrates the potential for ultrasonic misting fountains to cause illness in the home. In view of the increasing popularity of these devices, humidifier lung and humidifier fever should be considered in the differential diagnosis of patients with unexplained pulmonary or flu-like illnesses with fever.

  2. [Extrinsic allergic alveolitis--rarely diagnosed disease].

    Science.gov (United States)

    Lauková, D; Marget, I; Plutinský, J

    2009-05-01

    Extrinsic allergic alveolitis (EAA), known as hypersensitive pneumonitis, causes interstitial lung involvement by inhaled antigen. The clinical presentation of the disease has been defined as acute, subacute and chronic. The most often symptoms of the acute form of the disease are flu-like symptoms, dyspnoe and cough. The progressive dyspnoe in particullary is characterized for the chronic form of EAA. Dyspnoe is worsed, if the disease is combinied with usual respiratory infection or reexposition of inhaled antigen. It seems the diagnostic definition of EAA should be easy and prevalence of EAA relative high. The disease belongs to the group of interstitial lung diseases and it is underestimated as a matter of fact. The clinic, radiographic, laboratory and histologic abnormalities are results of inhaled antigen contact and support the diagnosis of EAA. Specific IgG antibodies against the offending antigen along with them are consedered to be detected (established) of EAA.

  3. Extrinsic and intrinsic determinants of nerve regeneration

    Directory of Open Access Journals (Sweden)

    Toby A. Ferguson

    2011-01-01

    Full Text Available After central nervous system (CNS injury axons fail to regenerate often leading to persistent neurologic deficit although injured peripheral nervous system (PNS axons mount a robust regenerative response that may lead to functional recovery. Some of the failures of CNS regeneration arise from the many glial-based inhibitory molecules found in the injured CNS, whereas the intrinsic regenerative potential of some CNS neurons is actively curtailed during CNS maturation and limited after injury. In this review, the molecular basis for extrinsic and intrinsic modulation of axon regeneration within the nervous system is evaluated. A more complete understanding of the factors limiting axonal regeneration will provide a rational basis, which is used to develop improved treatments for nervous system injury.

  4. Intrinsic and Extrinsic Motivation for Stereotypic and Repetitive Behavior

    Science.gov (United States)

    Joosten, Annette V.; Bundy, Anita C.; Einfeld, Stewart L.

    2009-01-01

    This study provides evidence for intrinsic and extrinsic motivators for stereotypical and repetitive behavior in children with autism and intellectual disability and children with intellectual disability alone. We modified the Motivation Assessment Scale (MAS) (1988b); dividing it into intrinsic and extrinsic measures and adding items to assess…

  5. A prototype empirical framework of intrinsic and extrinsic EERQI indicators

    NARCIS (Netherlands)

    Mooij, Ton

    2012-01-01

    The research question is: What do statistical analyses show us about the relationships between intrinsic and extrinsic indicators of quality and what does this mean when constructing a prototype EERQI framework? The pilot study involved the scoring on both intrinsic and extrinsic indica-tors for 177

  6. Extrinsic Isoperimetric Analysis on Submanifolds with Curvatures bounded from below

    DEFF Research Database (Denmark)

    Markvorsen, Steen; Palmer, Vicente

    2010-01-01

    within the extrinsic ball from a given starting point before they hit the boundary of the extrinsic ball. In those cases, where we may extend our analysis to hold all the way to infinity, we apply a capacity comparison technique to obtain a sufficient condition for the submanifolds to be parabolic, i...

  7. Recruiter-Applicant Differences in Perceptions of Extrinsic Rewards.

    Science.gov (United States)

    David, Kermit R., Jr.; And Others

    1991-01-01

    Examined how accurate recruiters would be in estimating relative preferences of college seniors for important category of extrinsic rewards. Compared preferences of 602 graduating college seniors for 11 extrinsic rewards with preference estimates of 486 recruiters. Recruiters underestimated importance of medical and life insurance, pension plans,…

  8. Extrinsic Rewards Are Education's Past, Not Its Future.

    Science.gov (United States)

    Schaps, Eric; Lewis, Catherine

    1991-01-01

    Robert Slavin's position--that extrinsic rewards promote student motivation and learning--may be valid within the context of a "facts-and-skills" curriculum. However, extrinsic rewards are unnecessary when schools offer engaging learning activities; programs addressing social, ethical, and cognitive development; and a supportive…

  9. Simultaneous bilateral contracture of the infraspinatus muscle.

    Science.gov (United States)

    Franch, J; Bertran, J; Remolins, G; Fontecha, P; Díaz-Bertrana, M C; Durall, I

    2009-01-01

    A case of bilateral fibrotic contracture of the infraspinatus muscles in a five-year-old Belgian Shepherd dog is described. The dog was presented with progressive forelimb lameness with postural and gait abnormalities three months after an episode of overexertion. When walking, the lower part of both forelimbs swung in a lateral arc causing a circumduction movement and in the standing position, the dog showed elbow adduction with external rotation of the distal part of both front limbs. Orthopaedic examination revealed bilateral atrophy of both infraspinatus and supraspinatus muscles and restriction in the range of motion of both shoulders, especially when attempting abduction and flexion. No specific findings were observed in the shoulder or elbow radiographs but hyperechogenic areas were evident in the ultrasonographic examination of both infraspinatus muscles. A diagnosis of fibrotic contracture of both infraspinatus muscles was established and bilateral tenectomy of the insertion tendons of the infraspinatus muscles was performed. Complete recovery of the animal was achieved after the surgery, which was confirmed in a long-term follow-up (10 months). In conclusion, physical examination and ultrasonography allowed a proper diagnosis of the condition, and tenectomy of the infraspinatus muscles resulted in a complete recovery of the patient even with bilateral involvement.

  10. How forelimb and hindlimb function changes with incline and perch diameter in the green anole, Anolis carolinensis.

    Science.gov (United States)

    Foster, Kathleen L; Higham, Timothy E

    2012-07-01

    The range of inclines and perch diameters in arboreal habitats poses a number of functional challenges for locomotion. To effectively overcome these challenges, arboreal lizards execute complex locomotor behaviors involving both the forelimbs and the hindlimbs. However, few studies have examined the role of forelimbs in lizard locomotion. To characterize how the forelimbs and hindlimbs differentially respond to changes in substrate diameter and incline, we obtained three-dimensional high-speed video of green anoles (Anolis carolinensis) running on flat (9 cm wide) and narrow (1.3 cm) perches inclined at 0, 45 and 90 deg. Changes in perch diameter had a greater effect on kinematics than changes in incline, and proximal limb variables were primarily responsible for these kinematic changes. In addition, a number of joint angles exhibited greater excursions on the 45 deg incline compared with the other inclines. Anolis carolinensis adopted strategies to maintain stability similar to those of other arboreal vertebrates, increasing limb flexion, stride frequency and duty factor. However, the humerus and femur exhibited several opposite kinematic trends with changes in perch diameter. Further, the humerus exhibited a greater range of motion than the femur. A combination of anatomy and behavior resulted in differential kinematics between the forelimb and the hindlimb, and also a potential shift in the propulsive mechanism with changes in external demand. This suggests that a better understanding of single limb function comes from an assessment of both forelimbs and hindlimbs. Characterizing forelimb and hindlimb movements may reveal interesting functional differences between Anolis ecomorphs. Investigations into the physiological mechanisms underlying the functional differences between the forelimb and the hindlimb are needed to fully understand how arboreal animals move in complex habitats.

  11. Free Radicals and Extrinsic Skin Aging

    Directory of Open Access Journals (Sweden)

    Borut Poljšak

    2012-01-01

    Full Text Available Human skin is constantly directly exposed to the air, solar radiation, environmental pollutants, or other mechanical and chemical insults, which are capable of inducing the generation of free radicals as well as reactive oxygen species (ROS of our own metabolism. Extrinsic skin damage develops due to several factors: ionizing radiation, severe physical and psychological stress, alcohol intake, poor nutrition, overeating, environmental pollution, and exposure to UV radiation (UVR. It is estimated that among all these environmental factors, UVR contributes up to 80%. UV-induced generation of ROS in the skin develops oxidative stress, when their formation exceeds the antioxidant defence ability of the target cell. The primary mechanism by which UVR initiates molecular responses in human skin is via photochemical generation of ROS mainly formation of superoxide anion (O2−•, hydrogen peroxide (H2O2, hydroxyl radical (OH•, and singlet oxygen (1O2. The only protection of our skin is in its endogenous protection (melanin and enzymatic antioxidants and antioxidants we consume from the food (vitamin A, C, E, etc.. The most important strategy to reduce the risk of sun UVR damage is to avoid the sun exposure and the use of sunscreens. The next step is the use of exogenous antioxidants orally or by topical application and interventions in preventing oxidative stress and in enhanced DNA repair.

  12. Plasma opening switch with extrinsic magnetic field

    CERN Document Server

    Dolgachev, G; Maslennikov, D

    2001-01-01

    Summary form only given, as follows. We have demonstrated in series of experiments that plasma opening switch (POS) switching voltage (UPOS) is defined by energy density (w) deposited in the POS plasma. If we then consider a plasma erosion mainly responsible for the effect of POS switching (the erosion effect could be described by Hall or Child-Langmuir models) the energy density (w) could be measured as a function of a system "macro-parameter" such as the initial charging voltage of the capacity storage system (the Marx pulsed voltage generator) UMarx. The POS voltage in this case could be given by UPOS"aw=aUMarx4/7, where a is a constant. This report demonstrates that for the high-impedance POS which has limited charge density transferred through the POS plasma a"2.5 (MV3/7) with no external magnetic field applied. The use of the extrinsic magnetic field allows to increase a up to 3.6 (MV3/7) and to achieve higher voltages at the opening phase - UPOS=3.6UMarx4/7. To verify this approach set of experimental ...

  13. Twisting Fluorescence through Extrinsic Chiral Antennas.

    Science.gov (United States)

    Yan, Chen; Wang, Xiaolong; Raziman, T V; Martin, Olivier J F

    2017-03-22

    Plasmonic antennas and planar structures have been undergoing intensive developments in order to control the scattering and absorption of light. One specific class, extrinsic chiral surfaces, that does not possess 2-fold rotational symmetry exhibits strong asymmetric transmission for different circular polarizations under obliquely incident illumination. In this work, we show that the design of those surfaces can be optimized with complex multipolar resonances in order to twist the fluorescence emission from nearby molecules. While this emission is usually dipolar and linearly polarized, the interaction with these resonances twists it into a multipolar radiation pattern with opposite helicity in different directions. The proposed structure maximizes this effect and provides control over the polarization of light. Splitting of left- and right-handed circularly polarized light is experimentally obtained in the backward direction. These results highlight the intricate interplay between the near-field absorption and the far-field scattering of a plasmonic nanostructure and are further used for modifying the emission of incoherent quantum sources. Our finding can potentially lead to the development of polarization- and angle-resolved ultracompact optical devices.

  14. The HRCT features of extrinsic allergic alveolitis.

    Science.gov (United States)

    Hartman, Thomas E

    2003-08-01

    Exposure to organic dusts can produce an immune-mediated inflammatory response in sensitized individuals. The pulmonary disease caused by this response has been called extrinsic allergic alveolitis (EAA) or hypersensitivity pneumonitis. The clinical phases associated with this process have been termed acute, subacute, and chronic. There are corresponding imaging findings that are characteristic of each of these phases, although there is some overlap between the phases. The acute phase is characterized by confluent opacities that may mimic infection or edema. The subacute phase is characterized by centrilobular nodules, areas of ground-glass attenuation, a mosaic perfusion pattern, and air trapping on expiratory imaging. The chronic phase is characterized by subpleural irregular linear opacities with associated architectural distortion. Honeycombing may sometimes also be present. In the acute and subacute phases, the disease is predominantly in the lower lungs, whereas in chronic EAA the findings are predominant in the mid to upper lungs. Although the high-resolution computed tomography findings individually are nonspecific, the combination of the findings coupled with the distribution of the findings can often narrow the differential or allow a presumptive diagnosis of EAA to be made.

  15. The effect of induced forelimb lameness on thoracolumbar kinematics during treadmill locomotion.

    Science.gov (United States)

    Gómez Alvarez, C B; Wennerstrand, J; Bobbert, M F; Lamers, L; Johnston, C; Back, W; van Weeren, P R

    2007-05-01

    Lameness has often been suggested to result in altered movement of the back, but there are no detailed studies describing such a relationship in quantitative terms. To quantify the effect of induced subtle forelimb lameness on thoracolumbar kinematics in the horse. Kinematics of 6 riding horses was measured at walk and at trot on a treadmill before and after the induction of reversible forelimb lameness grade 2 (AAEP scale 1-5). Ground reaction forces (GRF) for individual limbs were calculated from kinematics. The horses significantly unloaded the painful limb by 11.5% at trot, while unloading at walk was not significant. The overall flexion-extension range of back motion decreased on average by 0.2 degrees at walk and increased by 3.3 degrees at trot (P<0.05). Changes in angular motion patterns of vertebral joints were noted only at trot, with an increase in flexion of 0.9 degrees at T10 (i.e. angle between T6, T10 and T13) during the stance phase of the sound diagonal and an increase in extension of the thoracolumbar area during stance of the lame diagonal (0.7degrees at T13, 0.8 degres at T17, 0.5 degres at L1, 0.4 degrees at L3 and 0.3 degrees at L5) (P<0.05). Lameness further caused a lateral bending of the cranial thoracic vertebral column towards the lame side (1.3 degrees at T10 and 0.9 degrees at T13) (P<0.05) during stance of the lame diagonal. Both range of motion and vertebral angular motion patterns are affected by subtle forelimb lameness. At walk, the effect is minimal, at trot the horses increased the vertebral range of motion and changed the pattern of thoracolumbar motion in the sagittal and horizontal planes, presumably in an attempt to move the centre of gravity away from the lame side and reduce the force on the affected limb. Subtle forelimb lameness affects thoracolumbar kinematics. Future studies should aim at elucidating whether the altered movement patterns lead to back and/or neck dysfunction in the case of chronic lameness.

  16. An exploratory investigation into the role of extrinsic factors in ...

    African Journals Online (AJOL)

    Seugnet

    extrinsic factors in consumer decision-making for interior soft ... buy, in a passive manner, what retailers have to offer. Instead, they .... one's self-concept: the consumption of interior prod- .... important influencing variable in consumer decision-.

  17. The effects of extrinsic rewards on children's intrinsic motivation

    OpenAIRE

    大槻, 千秋

    1981-01-01

    An experiment was conducted with preschool children to test whether a person's intrinsic motivation in an activity may be decreased by extrinsic salient rewards in Japan like in America. Children solved some jigsaw puzzles and received assorted candies, then they were observed how long they did other jigsaw puzzles. The results showed that the effects of extrinsic rewards on intrinsic motivation in an activity varied with the subject's social background. In uptown children's intrinsic motivat...

  18. The effects of extrinsic rewards on children's intrinsic motivation

    OpenAIRE

    大槻, 千秋

    1981-01-01

    An experiment was conducted with preschool children to test whether a person's intrinsic motivation in an activity may be decreased by extrinsic salient rewards in Japan like in America. Children solved some jigsaw puzzles and received assorted candies, then they were observed how long they did other jigsaw puzzles. The results showed that the effects of extrinsic rewards on intrinsic motivation in an activity varied with the subject's social background. In uptown children's intrinsic motivat...

  19. Extrinsic Rewards: An Adventist Curriculum Perspective for Classroom Management

    OpenAIRE

    Nadine A. Joseph

    2014-01-01

    Extrinsic rewards refer to gifts used as a form of motivation for students’ to attain an academic goal, or given when that particular goal is reached. Though the use of extrinsic rewards have been proven to have some impact on’ behavior change, such as academic performance, the absence of rewards can cause students’ to revert to the initial unwanted behavior. Consequently, the curricula focus in the Adventist classroom should address the deeper issues that affect behavior and implement the us...

  20. A novel approach to induction and rehabilitation of deficits in forelimb function in a rat model of ischemic stroke

    Institute of Scientific and Technical Information of China (English)

    Jessica Mary LIVINGSTON-THOMAS; Andrew Wilson HUME; Tracy Ann DOUCETTE; Richard Andrew TASKER

    2013-01-01

    Aim:Constraint-induced movement therapy (CIMT),which forces use of the impaired arm following unilateral stroke,promotes functional recovery in the clinic but animal models of CIMT have yielded mixed results.The aim of this study is to develop a refined endothelin-1 (ET-1) model of focal ischemic injury in rats that resulted in reproducible,well-defined lesions and reliable upper extremity impairments,and to determine if an appetitively motivated form of rehabilitation (voluntary forced use movement therapy; FUMT)would accelerate post-ischemic motor recovery.Methods:Male Sprague Dawley rats (3 months old) were given multiple intracerebral microinjections of ET-1 into the sensorimotor cortex and dorsolateral striatum.Sham-operated rats received the same surgical procedure up to but not includingthe drill holes on the skull.Functional deficits were assessed using two tests of forelimb placing,a forelimb postural reflex test,a forelimb asymmetry test,and a horizontal ladder test.In a separate experiment ET-1 stroke rats were subjected to daily rehabilitation with FUMT or with a control therapy beginning on post-surgery d 5.Performance and post-mortem analysis of lesion volume and regional BDNF expression were measured.Results:Following microinjections of ET-1 animals exhibited significant deficits in contralateral forelimb function on a variety of tests compared with the sham group.These deficits persisted for up to 20 d with no mortality and were associated with consistent lesion volumes.FUMT therapy resulted in a modest but significantly accelerated recovery in the forelimb function as compared with the control therapy,but did not affect lesion size or BDNF expression in the ipsilesional hemisphere.Conclusion:We conclude that refined ET-1 microinjection protocols and forcing use of the impaired forelimb in an appetitively motivated paradigm may prove useful in developing strategies to study post-ischemic rehabilitation and neuroplasticity.

  1. Forelimb anatomy and the discrimination of the predatory behavior of carnivorous mammals: the thylacine as a case study.

    Science.gov (United States)

    Janis, Christine M; Figueirido, Borja

    2014-12-01

    Carnivorous mammals use their forelimbs in different ways to capture their prey. Most terrestrial carnivores have some cursorial (running) adaptations, but ambush predators retain considerable flexibility in their forelimb movement, important for grappling with their prey. In contrast, predators that rely on pursuit to run down their prey have sacrificed some of this flexibility for locomotor efficiency, in the greater restriction of the forelimb motion to the parasagittal plane. In this article, we measured aspects of the forelimb anatomy (44 linear measurements) in 36 species of carnivorous mammals of known predatory behavior, and used multivariate analyses to investigate how well the forelimb anatomy reflects the predatory mode (ambush, pursuit, or pounce-pursuit). A prime intention of this study was to establish morphological correlates of behavior that could then be applied to fossil mammals: for this purpose, five individuals of the recently extinct thylacine (Thylacinus cynocephalus) were also included as unknowns. We show that the three different types of predators can be distinguished by their morphology, both in analyses where all the forelimb bones are included together, and in the separate analyses of each bone individually. Of particular interest is the ability to distinguish between the two types of more cursorial predators, pursuit and pounce-pursuit, which have previously been considered as primarily size-based categories. Despite a prior consideration of the thylacine as a "pounce-pursuit" or an "ambush" type of predator, the thylacines did not consistently cluster with any type of predatory carnivores in our analyses. Rather, the thylacines appeared to be more generalized in their morphology than any of the extant carnivores. The absence of a large diversity of large carnivorous mammals in Australia, past and present, may explain the thylacine's generalized morphology.

  2. Posture and mechanics of the forelimbs of Brachiosaurus brancai (Dinosauria: Sauropoda

    Directory of Open Access Journals (Sweden)

    A. Christian

    1999-01-01

    Full Text Available The posture and mechanics of the forelimbs of Brachiosaurus brancai were analysed with the help of biomechanical models. Peak forces in the joints due to acceleration of the fraction of body weight carried on the shoulder joints are critical in models with completely straight, column-like limbs and a rigid shoulder girdle. During fast walking, either the forelimbs were flexed at the elbows during the middle of the support phase or the apparently rigid shoulder girdle allowed movements of the shoulder joints relative to the trunk. The overall construction of Brachiosaurus was related to an extreme task, browsing high above the ground. Consequently, versatility was very restricted. Die Stellung und die Mechanik der Vorderbeine von Brachiosaurus brancai wurden mit Hilfe von biomechanischen Modellen untersucht. Kraftspitzen aufgrund von Beschleunigungen des von den Schultern getragenen Anteils der Körpermasse erscheinen in Modellen mit völlig geraden, säulenförmigen Vorderbeinen und einem unbeweglichen Schultergürtel problematisch. Während des schnellen Gehens waren entweder die Vorderbeine in der Mitte der Stützphase in den Ellenbogengelenken gebeugt oder der scheinbar rigide Schultergürtel erlaubte Bewegungen der Schultergelenke relativ zum Brustkorb. Die Gesamtkonstruktion von Brachiosaurus war auf die Ausübung einer extremen Tätigkeit, die Nahrungsaufnahme in großer Höhe, ausgerichtet. Die Konsequenz war eine geringe Vielseitigkeit. doi:10.1002/mmng.1999.4860020103

  3. Three-dimensional skeletal kinematics of the shoulder girdle and forelimb in walking Alligator

    Science.gov (United States)

    Baier, David B; Gatesy, Stephen M

    2013-01-01

    Crocodylians occupy a key phylogenetic position for investigations of archosaur locomotor evolution. Compared to the well-studied hindlimb, relatively little is known about the skeletal movements and mechanics of the forelimb. In this study, we employed manual markerless XROMM (X-ray Reconstruction Of Moving Morphology) to measure detailed 3-D kinematics of the shoulder girdle and forelimb bones of American alligators (Alligator mississippiensis) walking on a treadmill. Digital models of the interclavicle, scapulocoracoid, humerus, radius and ulna were created using a 3-D laser scanner. Models were articulated and aligned to simultaneously recorded frames of fluoroscopic and standard light video to reconstruct and measure joint motion. Joint coordinate systems were established for the coracosternal, glenohumeral and elbow joints. Our analysis revealed that the limb joints only account for about half of fore/aft limb excursion; the remaining excursion results from shoulder girdle movements and lateral bending of the vertebral column. Considerable motion of each scapulocoracoid relative to the vertebral column is consistent with coracosternal mobility. The hemisellar design of the glenohumeral joint permits some additional translation, or sliding in the fore-aft plane, but this movement does not have much of an effect on the distal excursion of the bone. PMID:24102540

  4. Bat Accelerated Regions Identify a Bat Forelimb Specific Enhancer in the HoxD Locus.

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    Betty M Booker

    2016-03-01

    Full Text Available The molecular events leading to the development of the bat wing remain largely unknown, and are thought to be caused, in part, by changes in gene expression during limb development. These expression changes could be instigated by variations in gene regulatory enhancers. Here, we used a comparative genomics approach to identify regions that evolved rapidly in the bat ancestor, but are highly conserved in other vertebrates. We discovered 166 bat accelerated regions (BARs that overlap H3K27ac and p300 ChIP-seq peaks in developing mouse limbs. Using a mouse enhancer assay, we show that five Myotis lucifugus BARs drive gene expression in the developing mouse limb, with the majority showing differential enhancer activity compared to the mouse orthologous BAR sequences. These include BAR116, which is located telomeric to the HoxD cluster and had robust forelimb expression for the M. lucifugus sequence and no activity for the mouse sequence at embryonic day 12.5. Developing limb expression analysis of Hoxd10-Hoxd13 in Miniopterus natalensis bats showed a high-forelimb weak-hindlimb expression for Hoxd10-Hoxd11, similar to the expression trend observed for M. lucifugus BAR116 in mice, suggesting that it could be involved in the regulation of the bat HoxD complex. Combined, our results highlight novel regulatory regions that could be instrumental for the morphological differences leading to the development of the bat wing.

  5. Three-dimensional Torques and Power of Horse Forelimb Joints at Trot

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    Clayton, H M; Mullineaux, D R

    2011-01-01

    Reasons for Performing Study: Equine gait analysis has focused on 2D analysis in the sagittal plane, while descriptions of 3D kinetics and ground reaction force could provide more information on the Equine gait analysis. Hypothesis or Objectives: The aim of this study was to characterize the 3D torques and powers of the forelimb joints at trotting. Methods: Eight sound horses were used in the study. A full 3D torque and power for elbow, carpus, fetlock, pastern and coffin joints of right forelimb in horses at trot were obtained by calculating the inverse kinetics of simplified link segmental model. Results: Over two third of energy (70%) generated by all joints come from stance phase, and most of energy generated was by elbow joint both in stance (77%) and sway (88%) phases. Energy absorbed by all joints during stance (40%) and sway (60%) phases respectively is not a big difference. During stance phase, all most two third of energy (65%) absorbed was by fetlock joint, while over two third of energy (74%) abso...

  6. Functional and biomechanic aspects of the scapular girdle and forelimbs of Unaysaurus tolentinoiLeal et al., 2004 (Saurischia: Sauropodomorpha)

    Science.gov (United States)

    Vargas-Peixoto, Dilson; Da-Rosa, Átila Augusto Stock; Gallo de França, Marco Aurélio

    2015-08-01

    This study presents evidence about the biomechanics and forelimbs functionality of the basal sauropodomorph Unaysaurus tolentinoi (upper portion of the SM2 sequence, Santa Maria Supersequence, Upper Triassic from southern Brazil). Maximum and minimum motion angles were inferred in the joints, disregarding the presence and/or thickness of cartilage. Furthermore, processes and external structures of the bones were analyzed in attributing the functionality of forelimbs. Unaysaurus tolentinoi had well-developed grapple ability. However, the preserved elements and their osteological features are not conclusive about strictly bipedalism or quadrupedalism in U. tolentinoi.

  7. Extrinsic value orientation and affective forecasting: overestimating the rewards, underestimating the costs.

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    Sheldon, Kennon M; Gunz, Alexander; Nichols, Charles P; Ferguson, Yuna

    2010-02-01

    We examined affective forecasting errors as a possible explanation of the perennial appeal of extrinsic values and goals. Study 1 found that although people relatively higher in extrinsic (money, fame, image) compared to intrinsic (growth, intimacy, community) value orientation (REVO) are less happy, they nevertheless believe that attaining extrinsic goals offers a strong potential route to happiness. Study 2's longitudinal experimental design randomly assigned participants to pursue either 3 extrinsic or 3 intrinsic goals over 4 weeks, and REVO again predicted stronger forecasts regarding extrinsic goals. However, not even extrinsically oriented participants gained well-being benefits from attaining extrinsic goals, whereas all participants tended to gain in happiness from attaining intrinsic goals. Study 3 showed that the effect of REVO on forecasts is mediated by extrinsic individuals' belief that extrinsic goals will satisfy autonomy and competence needs. It appears that some people overestimate the emotional benefits of achieving extrinsic goals, to their potential detriment.

  8. Neuronal Correlates of Functional Coupling between Reach- and Grasp-Related Components of Muscle Activity

    Science.gov (United States)

    Geed, Shashwati; McCurdy, Martha L.; van Kan, Peter L. E.

    2017-01-01

    Coordinated reach-to-grasp movements require precise spatiotemporal synchrony between proximal forelimb muscles (shoulder, elbow) that transport the hand toward a target during reach, and distal muscles (wrist, digit) that simultaneously preshape and orient the hand for grasp. The precise mechanisms through which the redundant neuromuscular circuitry coordinates reach with grasp, however, remain unclear. Recently, Geed and Van Kan (2016) demonstrated, using exploratory factor analysis (EFA), that limited numbers of global, template-like transport/preshape- and grasp-related muscle components underlie the complexity and variability of intramuscular electromyograms (EMGs) of up to 21 distal and proximal muscles recorded while monkeys performed reach-to-grasp tasks. Importantly, transport/preshape- and grasp-related muscle components showed invariant spatiotemporal coupling, which provides a potential mechanism for coordinating forelimb muscles during reach-to-grasp movements. In the present study, we tested whether ensemble discharges of forelimb neurons in the cerebellar nucleus interpositus (NI) and its target, the magnocellular red nucleus (RNm), a source of rubrospinal fibers, function as neuronal correlates of the transport/preshape- and grasp-related muscle components we identified. EFA applied to single-unit discharges of populations of NI and RNm neurons recorded while the same monkeys that were used previously performed the same reach-to-grasp tasks, revealed neuronal components in the ensemble discharges of both NI and RNm neuronal populations with characteristics broadly similar to muscle components. Subsets of NI and RNm neuronal components were strongly and significantly crosscorrelated with subsets of muscle components, suggesting that similar functional units of reach-to-grasp behavior are expressed by NI and RNm neuronal populations and forelimb muscles. Importantly, like transport/preshape- and grasp-related muscle components, their NI and RNm

  9. Perfectionism and life aspirations in intrinsically and extrinsically religious individuals.

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    Steffen, Patrick R

    2014-08-01

    Religiosity is related to positive health and life satisfaction but the pathways through which this occurs have not been clearly delineated. The purpose of this study was to examine potential mediators of the relationships between intrinsic and extrinsic religiosity and negative affect and life satisfaction. Perfectionism and life aspirations are two possible pathways through which religious orientation is related to outcome. It was hypothesized that adaptive perfectionism and intrinsic life aspirations would act as mediators between intrinsic religiosity and negative affect and life satisfaction, and that maladaptive perfectionism and extrinsic life aspirations would act as mediators between the extrinsic religiosity and negative affect and life satisfaction. Two consecutive samples of religious college students (N = 540 and N = 485) completed measures of the Age Universal Religious Orientation Index, the Frost Multi-Dimensional Perfectionism Scale, the Aspiration Index, the Beck Depression Inventory-II, the Spielberger State-Trait Anxiety Inventory, and the Satisfaction with Life Scale. Intrinsic religiosity had a direct negative relationship with negative affect and positive relationship with life satisfaction. Contrary to the hypotheses, intrinsic religiosity had its strongest indirect effect via maladaptive perfectionism such that increased intrinsic religiosity was related to decreased maladaptive perfectionism which in turn lead to better negative affect and life satisfaction. Extrinsic religiosity was related to increased maladaptive perfectionism and thereby indirectly contributed to worse negative affect and life satisfaction. Interestingly, when the effects of maladaptive perfectionism were controlled, the direct effects of extrinsic religiosity were related to reduced negative affect and increased life satisfaction. Overall, the strongest mediator in this study of both intrinsic and extrinsic religiosity was maladaptive perfectionism, with intrinsic

  10. INTRINSIC AND EXTRINSIC MOTIVATION - AN INVESTIGATION OF PERFORMANCE CORRELATION

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    Abrudan Maria-Madela

    2011-07-01

    Full Text Available A series of research untaken in the last decade have revealed some interesting aspects regarding the effects of different types of motivation on performance. Among the researchers who have shown interest in this field we can number: Richard Ryan, Edward Deci, Sam Glucksberg, Dan Ariely, Robert Eisenhower, Linda Shanock, analysts from London School of Economics, and others. Their findings suggest that extrinsic incentives may have a negative impact on overall performance, but a general agreement in this respect has not been reached. In this paper we intend to shed some light upon the relationship between intrinsic and extrinsic motivation and performance. Experts define intrinsic motivation as being the execution of a task or activity because of the inherent satisfaction arising from it rather than due to some separate outcome. In contrast with intrinsic motivation, we speak of extrinsic motivation whenever an activity is done in order to attain some separable outcome. With the purpose of contributing to the clarification of the links between concepts, we initiated and conducted an explanatory research. The research is based on the analysis of the relations between the results obtained by third year students and their predominant type of motivation. For this, we formulated and tested four work hypotheses using a combination of quantitative methods (investigation and qualitative methods (focus group. After the validation of the questionnaires, the respondents were divided into four categories: intrinsically motivated, extrinsically motivated, both intrinsically and extrinsically motivated and unmotivated. To analyze the collected data, we made use of Excel and SPSS. Some of the primary conclusions of the research are as follows: as the average increases, the percent of individuals having both extrinsic and intrinsic motivation is decreasing; the highest percentage of unmotivated students is concentrated in the highest average category; Female

  11. Mechanism of Forelimb Motor Function Restoration after Cervical Spinal Cord Hemisection in Rats: A Comparison of Juveniles and Adults

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    Atsushi Hasegawa

    2016-01-01

    Full Text Available The aim of this study was to investigate forelimb motor function after cervical spinal cord injury in juvenile and adult rats. Both rats received a left segmental hemisection of the spinal cord after C3-C4 laminectomy. Behavioral evaluation of motor function was monitored and assessed using the New Rating Scale (NRS and Forelimb Locomotor Scale (FLS and by measuring the range of motion (ROM of both the elbow and wrist. Complete left forelimb motor paralysis was observed in both rats. The NRS showed motor function recovery restored to 50.2±24.7% in juvenile rats and 34.0±19.8% in adult rats. FLS was 60.4±26.8% in juvenile rats and 46.5±26.9% in adult rats. ROM of the elbow and wrist were 88.9±20.6% and 44.4±24.1% in juvenile rats and 70.0±29.2% and 40.0±21.1% in adult rats. Thus, the NRS and ROM of the elbow showed a significant difference between age groups. These results indicate that left hemisection of the cervical spinal cord was not related to right-sided motor functions. Moreover, while motor paralysis of the left forelimb gradually recovered in both groups, the improvement was greater in juvenile rats.

  12. The effect of extrinsic noise on cellular decision making

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    Roberts, Elijah; Assaf, Michael; Luthey-Schulten, Zaida; Goldenfeld, Nigel

    2013-03-01

    Many cellular processes are not deterministic, i.e., genetically identical cells can display different phenotypic behavior even in identical environments. Such processes involve cellular decision making, in which individual cells randomly make choices determining their fate. One view is that the stochastic nature of cellular decision making is due to noise present in the biomolecular interaction networks. Most previous work has focused on the role of intrinsic noise of these networks. Yet, especially in the high copy-number regime, extrinsic noise may be much more significant, likely governing the overall dynamics. Here we develop a theoretical framework describing the combined effect of intrinsic and extrinsic noise on the stochastic dynamics of genetic switches responsible for cellular decision making. We do so by devising a semi-classical theory accounting for extrinsic noise as an effective species. Our theory, corroborated by extensive Monte-Carlo simulations, is tested on a simple bistable self-regulating gene model, and is then generalized to gain insight on the behavior of the lac genetic switch under extrinsic noise. We show that extrinsic noise not only significantly lowers the escape time from a phenotypic state, but can fundamentally change the actual escape process.

  13. Retrograde migration of pectoral girdle muscle precursors depends on CXCR4/SDF-1 signaling.

    Science.gov (United States)

    Masyuk, Maryna; Abduelmula, Aisha; Morosan-Puopolo, Gabriela; Ödemis, Veysel; Rehimi, Rizwan; Khalida, Nargis; Yusuf, Faisal; Engele, Jürgen; Tamamura, Hirokazu; Theiss, Carsten; Brand-Saberi, Beate

    2014-11-01

    In vertebrates, muscles of the pectoral girdle connect the forelimbs with the thorax. During development, the myogenic precursor cells migrate from the somites into the limb buds. Whereas most of the myogenic precursors remain in the limb bud to form the forelimb muscles, several cells migrate back toward the trunk to give rise to the superficial pectoral girdle muscles, such as the large pectoral muscle, the latissimus dorsi and the deltoid. Recently, this developing mode has been referred to as the "In-Out" mechanism. The present study focuses on the mechanisms of the "In-Out" migration during formation of the pectoral girdle muscles. Combining in ovo electroporation, tissue slice-cultures and confocal laser scanning microscopy, we visualize live in detail the retrograde migration of myogenic precursors from the forelimb bud into the trunk region by live imaging. Furthermore, we present for the first time evidence for the involvement of the chemokine receptor CXCR4 and its ligand SDF-1 during these processes. After microsurgical implantations of CXCR4 inhibitor beads in the proximal forelimb region of chicken embryos, we demonstrate with the aid of in situ hybridization and live-cell imaging that CXCR4/SDF-1 signaling is crucial for the retrograde migration of pectoral girdle muscle precursors. Moreover, we analyzed the MyoD expression in CXCR4-mutant mouse embryos and observed a considerable decrease in pectoral girdle musculature. We thus demonstrate the importance of the CXCR4/SDF-1 axis for the pectoral girdle muscle formation in avians and mammals.

  14. Identification of cDNAs associated with late dedifferentiation in adult newt forelimb regeneration.

    Science.gov (United States)

    Vascotto, Sandy G; Beug, Shawn; Liversage, Richard A; Tsilfidis, Catherine

    2005-06-01

    Epimorphic limb regeneration in the adult newt involves the dedifferentiation of differentiated cells to yield a pluripotent blastemal cell. These mesenchymal-like cells proliferate and subsequently respond to patterning and differentiation cues to form a new limb. Understanding the dedifferentiation process requires the selective identification of dedifferentiating cells within the heterogeneous population of cells in the regenerate. In this study, representational differences analysis was used to produce an enriched population of dedifferentiation-associated cDNA fragments. Fifty-nine unique cDNA fragments were identified, sequenced, and analyzed using bioinformatics tools and databases. Some of these clones demonstrate significant similarity to known genes in other species. Other clones can be linked by homology to pathways previously implicated in the dedifferentiation process. These data will form the basis for further analyses to elucidate the role of candidate genes in the dedifferentiation process during newt forelimb regeneration.

  15. Enhancement of bilateral cortical somatosensory evoked potentials to intact forelimb stimulation following thoracic contusion spinal cord injury in rats.

    Science.gov (United States)

    Bazley, Faith A; Maybhate, Anil; Tan, Chuen Seng; Thakor, Nitish V; Kerr, Candace; All, Angelo H

    2014-09-01

    The adult central nervous system is capable of significant reorganization and adaptation following neurotrauma. After a thoracic contusive spinal cord injury (SCI) neuropathways that innervate the cord below the epicenter of injury are damaged, with minimal prospects for functional recovery. In contrast, pathways above the site of injury remain intact and may undergo adaptive changes in response to injury. We used cortical somatosensory evoked potentials (SSEPs) to evaluate changes in intact forelimb pathways. Rats received a midline contusion SCI, unilateral contusion SCI, or laminectomy with no contusion at the T8 level and were monitored for 28 days post-injury. In the midline injury group, SSEPs recorded from the contralateral forelimb region of the primary somatosensory cortex were 59.7% (CI 34.7%, 84.8%; c(2) = 21.9; dof = 1; p = 2.9 ×10(-6)) greater than the laminectomy group; SSEPs from the ipsilateral somatosensory cortex were 47.6% (CI 18.3%, 77%; c(2) = 10.1; dof = 1; p = 0.001) greater. Activation of the ipsilateral somatosensory cortex was further supported by BOLD-fMRI, which showed increased oxygenation at the ipsilateral hemisphere at day seven post-injury. In the unilateral injury group, ipsilesional side was compared to the contralesional side. SSEPs on day 14 (148%; CI 111%, 185%) and day 21 (137%; CI 110%, 163%) for ipsilesional forelimb stimulation were significantly increased over baseline (100%). SSEPs recorded from the hindlimb sensory cortex upon ipsilesional stimulation were 33.9% (CI 14.3%, 53.4%; c(2) = 11.6; dof = 1; p = 0.0007) greater than contralesional stimulation. Therefore, these results demonstrate the ability of SSEPs to detect significant enhancements in the activation of forelimb sensory pathways following both midline and unilateral contusive SCI at T8. Reorganization of forelimb pathways may occur after thoracic SCI, which SSEPs can monitor to aid the development of future therapies.

  16. Sensory nerve conduction and nociception in the equine lower forelimb during perineural bupivacaine infusion along the palmar nerves

    Science.gov (United States)

    Zarucco, Laura; Driessen, Bernd; Scandella, Massimiliano; Cozzi, Francesca; Cantile, Carlo

    2010-01-01

    The purpose of this investigation was to study lateral palmar nerve (LPN) and medial palmar nerve (MPN) morphology and determine nociception and sensory nerve conduction velocity (SNCV) following placement of continuous peripheral nerve block (CPNB) catheters along LPN and MPN with subsequent bupivacaine (BUP) infusion. Myelinated nerve fiber distribution in LPN and MPN was examined after harvesting nerve specimens in 3 anesthetized horses and processing them for morphometric analysis. In 5 sedated horses, CPNB catheters were placed along each PN in both forelimbs. Horses then received in one forelimb 3 mL 0.125% BUP containing epinephrine 1:200 000 and 0.04% NaHCO3 per catheter site followed by 2 mL/h infusion over a 6-day period, while in the other forelimb equal amounts of saline (SAL) solution were administered. The hoof withdrawal response (HWR) threshold during pressure loading of the area above the dorsal coronary band was determined daily in both forelimbs. On day 6 SNCV was measured under general anesthesia of horses in each limb’s LPN and MPN to detect nerve injury, followed by CPNB catheter removal. The SNCV was also recorded in 2 anesthetized non-instrumented horses (sham controls). In both LPN and MPN myelinated fiber distributions were bimodal. The fraction of large fibers (>7 μm) was greater in the MPN than LPN (P < 0.05). Presence of CPNB catheters and SAL administration did neither affect measured HWR thresholds nor SNCVs, whereas BUP infusion suppressed HWRs. In conclusion, CPNB with 0.125% BUP provides pronounced analgesia by inhibiting sensory nerve conduction in the distal equine forelimb. PMID:21197231

  17. Expression of a hindlimb-determining factor Pitx1 in the forelimb of the lizard Pogona vitticeps during morphogenesis.

    Science.gov (United States)

    Melville, Jane; Hunjan, Sumitha; McLean, Felicity; Mantziou, Georgia; Boysen, Katja; Parry, Laura J

    2016-10-01

    With over 9000 species, squamates, which include lizards and snakes, are the largest group of reptiles and second-largest order of vertebrates, spanning a vast array of appendicular skeletal morphology. As such, they provide a promising system for examining developmental and molecular processes underlying limb morphology. Using the central bearded dragon (Pogona vitticeps) as the primary study model, we examined limb morphometry throughout embryonic development and characterized the expression of three known developmental genes (GHR, Pitx1 and Shh) from early embryonic stage through to hatchling stage via reverse transcription quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry (IHC). In this study, all genes were found to be transcribed in both the forelimbs and hindlimbs of P. vitticeps. While the highest level of GHR expression occurred at the hatchling stage, Pitx1 and Shh expression was greatest earlier during embryogenesis, which coincides with the onset of the differentiation between forelimb and hindlimb length. We compared our finding of Pitx1 expression-a hindlimb-determining gene-in the forelimbs of P. vitticeps to that in a closely related Australian agamid lizard, Ctenophorus pictus, where we found Pitx1 expression to be more highly expressed in the hindlimb compared with the forelimb during early and late morphogenesis-a result consistent with that found across other tetrapods. Expression of Pitx1 in forelimbs has only rarely been documented, including via in situ hybridization in a chicken and a frog. Our findings from both RT-qPCR and IHC indicate that further research across a wider range of tetrapods is needed to more fully understand evolutionary variation in molecular processes underlying limb morphology. © 2016 The Authors.

  18. Ketogenic diet improves forelimb motor function after spinal cord injury in rodents.

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    Femke Streijger

    Full Text Available High fat, low carbohydrate ketogenic diets (KD are validated non-pharmacological treatments for some forms of drug-resistant epilepsy. Ketones reduce neuronal excitation and promote neuroprotection. Here, we investigated the efficacy of KD as a treatment for acute cervical spinal cord injury (SCI in rats. Starting 4 hours following C5 hemi-contusion injury animals were fed either a standard carbohydrate based diet or a KD formulation with lipid to carbohydrate plus protein ratio of 3:1. The forelimb functional recovery was evaluated for 14 weeks, followed by quantitative histopathology. Post-injury 3:1 KD treatment resulted in increased usage and range of motion of the affected forepaw. Furthermore, KD improved pellet retrieval with recovery of wrist and digit movements. Importantly, after returning to a standard diet after 12 weeks of KD treatment, the improved forelimb function remained stable. Histologically, the spinal cords of KD treated animals displayed smaller lesion areas and more grey matter sparing. In addition, KD treatment increased the number of glucose transporter-1 positive blood vessels in the lesion penumbra and monocarboxylate transporter-1 (MCT1 expression. Pharmacological inhibition of MCTs with 4-CIN (α-cyano-4-hydroxycinnamate prevented the KD-induced neuroprotection after SCI, In conclusion, post-injury KD effectively promotes functional recovery and is neuroprotective after cervical SCI. These beneficial effects require the function of monocarboxylate transporters responsible for ketone uptake and link the observed neuroprotection directly to the function of ketones, which are known to exert neuroprotection by multiple mechanisms. Our data suggest that current clinical nutritional guidelines, which include relatively high carbohydrate contents, should be revisited.

  19. Schwann cell transplantation improves reticulospinal axon growth and forelimb strength after severe cervical spinal cord contusion.

    Science.gov (United States)

    Schaal, S M; Kitay, B M; Cho, K S; Lo, T P; Barakat, D J; Marcillo, A E; Sanchez, A R; Andrade, C M; Pearse, D D

    2007-01-01

    Schwann cell (SC) implantation alone has been shown to promote the growth of propriospinal and sensory axons, but not long-tract descending axons, after thoracic spinal cord injury (SCI). In the current study, we examined if an axotomy close to the cell body of origin (so as to enhance the intrinsic growth response) could permit supraspinal axons to grow onto SC grafts. Adult female Fischer rats received a severe (C5) cervical contusion (1.1 mm displacement, 3 KDyn). At 1 week postinjury, 2 million SCs ex vivo transduced with lentiviral vector encoding enhanced green fluorescent protein (EGFP) were implanted within media into the injury epicenter; injury-only animals served as controls. Animals were tested weekly using the BBB score for 7 weeks postimplantation and received at end point tests for upper body strength: self-supported forelimb hanging, forearm grip force, and the incline plane. Following behavioral assessment, animals were anterogradely traced bilaterally from the reticular formation using BDA-Texas Red. Stereological quantification revealed a twofold increase in the numbers of preserved NeuN+ neurons rostral and caudal to the injury/graft site in SC implanted animals, corroborating previous reports of their neuroprotective efficacy. Examination of labeled reticulospinal axon growth revealed that while rarely an axon was present within the lesion site of injury-only controls, numerous reticulospinal axons had penetrated the SC implant/lesion milieu. This has not been observed following implantation of SCs alone into the injured thoracic spinal cord. Significant behavioral improvements over injury-only controls in upper limb strength, including an enhanced grip strength (a 296% increase) and an increased self-supported forelimb hanging, accompanied SC-mediated neuroprotection and reticulospinal axon growth. The current study further supports the neuroprotective efficacy of SC implants after SCI and demonstrates that SCs alone are capable of supporting

  20. Extrinsic Motivation Index: A New Tool for Managing Labor Productivity

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    Berumen, S.A.

    2016-07-01

    Full Text Available The objective of this paper is to provide a tool of practical significance for HR managers and firm executives. This tool, which is called Extrinsic Motivation Index (EMI, is meant to measure the extrinsic motivation of employees. By measuring employees' extrinsic motivation, managers are able to track job satisfaction and, subsequently, implement measures aiming both to raise job satisfaction and to improve organizational commitment. In order to test the validity of the model, we apply the EMI to Faculty members at Spanish and German universities. We also carry out simulation experiments in order to to address all possible situations an organization most probably will have to deal with. The results point out significant differences in the level of motivation and commitment of Faculty members. Additionally, the analysis shows several ways in which an organization may manage job satisfaction issues according to on its level of resources.

  1. Intrinsic and Extrinsic Spin Hall Effects of Dirac Electrons

    Science.gov (United States)

    Fukazawa, Takaaki; Kohno, Hiroshi; Fujimoto, Junji

    2017-09-01

    We investigate the spin Hall effect (SHE) of electrons described by the Dirac equation, which is used as an effective model near the L-points in bismuth. By considering short-range nonmagnetic impurities, we calculate the extrinsic as well as intrinsic contributions on an equal footing. The vertex corrections are taken into account within the ladder type and the so-called skew-scattering type. The intrinsic SHE which we obtain is consistent with that of Fuseya et al. [https://doi.org/10.1143/JPSJ.81.093704" xlink:type="simple">J. Phys. Soc. Jpn. 81, 093704 (2012)]. It is found that the extrinsic contribution dominates the intrinsic one when the system is metallic. The extrinsic SHE due to the skew scattering is proportional to Δ/niu, where 2Δ is the band gap, ni is the impurity concentration, and u is the strength of the impurity potential.

  2. Intrinsic and extrinsic motivation for stereotypic and repetitive behavior.

    Science.gov (United States)

    Joosten, Annette V; Bundy, Anita C; Einfeld, Stewart L

    2009-03-01

    This study provides evidence for intrinsic and extrinsic motivators for stereotypical and repetitive behavior in children with autism and intellectual disability and children with intellectual disability alone. We modified the Motivation Assessment Scale (MAS) (1988b); dividing it into intrinsic and extrinsic measures and adding items to assess anxiety as an intrinsic motivator. Rasch analysis of data from 279 MASs (74 children) revealed that the items formed two unidimensional scales. Anxiety was a more likely intrinsic motivator than sensory seeking for children with dual diagnoses; the reverse was true for children with intellectual disability only. Escape and gaining a tangible object were the most common extrinsic motivators for those with dual diagnoses and attention and escape for children with intellectual disability.

  3. Olecranon orientation as an indicator of elbow joint angle in the stance phase, and estimation of forelimb posture in extinct quadruped animals.

    Science.gov (United States)

    Fujiwara, Shin-Ichi

    2009-09-01

    Reconstruction of limb posture is a challenging task in assessing functional morphology and biomechanics of extinct tetrapods, mainly because of the wide range of motions possible at each limb joint and because of our poor knowledge of the relationship between posture and musculoskeletal structure, even in the extant taxa. This is especially true for extinct mammals such as the desmostylian taxa Desmostylus and Paleoparadoxia. This study presents a procedure that how the elbow joint angles of extinct quadruped mammals can be inferred from osteological characteristics. A survey of 67 dried skeletons and 113 step cycles of 32 extant genera, representing 25 families and 13 orders, showed that the olecranon of the ulna and the shaft of the humerus were oriented approximately perpendicular to each other during the stance phase. At this angle, the major extensor muscles maximize their torque at the elbow joint. Based on this survey, I suggest that olecranon orientation can be used for inferring the elbow joint angles of quadruped mammals with prominent olecranons, regardless of taxon, body size, and locomotor guild. By estimating the elbow joint angle, it is inferred that Desmostylus would have had more upright forelimbs than Paleoparadoxia, because their elbow joint angles during the stance phase were approximately 165 degrees and 130 degrees , respectively. Difference in elbow joint angles between these two genera suggests possible differences in stance and gait of these two mammals.

  4. Cell-extrinsic consequences of epithelial stress: activation of protumorigenic tissue phenotypes.

    Science.gov (United States)

    Fordyce, Colleen A; Patten, Kelley T; Fessenden, Tim B; DeFilippis, RosaAnna; Hwang, E Shelley; Zhao, Jianxin; Tlsty, Thea D

    2012-12-07

    damage. The response to cell-extrinsic DNA damage characterized in vitro is recapitulated in vivo in DCIS lesions, which exhibit telomere loss, heightened DNA damage response, and increased activin A and cyclooxygenase-2 expression. These lesions are surrounded by a stroma characterized by increased expression of α smooth muscle actin and endothelial and immune cell infiltration. Thus, synergy between stromal and epithelial interactions, even at the initiating stages of carcinogenesis, appears necessary for the acquisition of malignancy and provides novel insights into where, when, and how the tumor stroma develops, allowing new therapeutic strategies.

  5. Extrinsic allergic alveolitis with an atypical immune expression.

    Science.gov (United States)

    Costa, Teresa; Rodrigues, Cidália; Arrobas, Ana

    2009-01-01

    Extrinsic allergic alveolitis and sarcoidosis are two granulomatosis of the lung characterized by non- -necrotizing granuloma. Both have typical bronchoalveolar lavage immunology, with opposite CD4/CD8 relation. However, sarcoidosis does not have such well defined etiology as extrinsic allergic alveolitis. The authors present two cases with similar clinical course, imagiology, lung function and immunology, although they both had an histology that was not concordant with the bronchoalveolar lavage, and with the peculiarity of being two elements of the same family, co -inhabitants and with a clinical presentation only a few weeks apart.

  6. CONSUMER EVALUATIONS OF BEAUTIFICATION PRODUCTS: EFFECTS OF EXTRINSIC CUES

    Directory of Open Access Journals (Sweden)

    Md. Humayun Kabir Chowdhury

    2006-01-01

    Full Text Available This study investigates the influence of extrinsic cues, i.e. brand image, perceived price, perceived quality, and perceived country of origin on consumers' evaluative judgments for beautification products. Multi-item measures were used for data collection. Resultsrevealed that three extrinsic cues: brand image, perceived quality, and perceived country of origin have positive and significant influence on consumers' brand evaluation of beautification brands. Only perceived price has shown no such influence on consumers' brand evaluation. Finally, unanswered questions and future researchdirections are presented.

  7. Intrinsic and extrinsic motivation and intention to breast-feed.

    Science.gov (United States)

    Wells, Kristen J; Thompson, Nancy J; Kloeblen-Tarver, Amy S

    2002-01-01

    To examine the feasibility of using the cognitive evaluation theory to examine pregnant women's intention to breast-feed. A questionnaire designed to measure intrinsic and extrinsic motivation was administered to 228 pregnant women. Results provide evidence for reliability and validity of the revised instrument in this population. A factor analysis suggests the instrument measures 2 types of intrinsic motivation, one type of extrinsic motivation, and motivation related to the baby. The instrument distinguished differences in motivation between women who intend to breast-feed and those who intend to formula feed. This study helps elucidate motivational factors involved in infant-feeding decisions.

  8. A new scenario of the evolutionary derivation of the mammalian diaphragm from shoulder muscles.

    Science.gov (United States)

    Hirasawa, Tatsuya; Kuratani, Shigeru

    2013-05-01

    The evolutionary origin of the diaphragm remains unclear, due to the lack of a comparable structure in other extant taxa. However, recent researches into the developmental mechanism of this structure have yielded new insights into its origin. Here we summarize current understanding regarding the development of the diaphragm, and present a possible scenario for the evolutionary acquisition of this uniquely mammalian structure. Recent developmental analyses indicate that the diaphragm and forelimb muscles are derived from a shared cell population during embryonic development. Therefore, the embryonic positions of forelimb muscle progenitors, which correspond to the position of the brachial plexus, likely played an important role in the evolution of the diaphragm. We surveyed the literature to reexamine the position of the brachial plexus among living amniotes and confirmed that the cervico-thoracic transition in ribs reflects the brachial plexus position. Using this osteological correlate, we concluded that the anterior borders of the brachial plexuses in the stem synapsids were positioned at the level of the fourth spinal nerve, suggesting that the forelimb buds were laid in close proximity of the infrahyoid muscles. The topology of the phrenic and suprascapular nerves of mammals is similar to that of subscapular and supracoracoid nerves, respectively, of the other amniotes, suggesting that the diaphragm evolved from a muscle positioned medial to the pectoral girdle (cf. subscapular muscle). We hypothesize that the diaphragm was acquired in two steps: first, forelimb muscle cells were incorporated into tissues to form a primitive diaphragm in the stem synapsid grade, and second, the diaphragm in cynodonts became entrapped in the region controlled by pulmonary development. © 2013 Anatomical Society.

  9. Influence of air pollution on extrinsic childhood asthma

    Energy Technology Data Exchange (ETDEWEB)

    Berciano, F.A.; Dominguez, J.; Alvarez, F.V.

    1989-02-01

    A crossed comparative study was done with 248 extrinsic asthmatic children living either in polluted or non-polluted areas (mean emission per year of sedimentary material greater than or less than 300 mg/m2/day, respectively) to establish the influence of air pollution on childhood extrinsic asthma. The mean number of wheezing crises per year was significantly higher for the children living in polluted areas (10.4 versus 7.69). In addition, incidence of severe asthma (types II, III, and IV) in children living in polluted areas was markedly increased whereas the slight form of asthma (type I) was more frequent in children living in non-polluted areas. No correlation, however, between the wheezing episodes and levels of atmospheric contaminants (fumes and SO/sub 2/) was detected when a group of 84 extrinsic asthmatic children living in polluted areas was studied longitudinally for a year. The data indicate that air pollution, as an isolated agent, plays a transient role in the appearance of wheezing episodes in subjects with extrinsic asthma. Results also suggest that the air pollution may potentiate wheezing episodes via alternative mechanisms.

  10. On the isoperimetric rigidity of extrinsic minimal balls

    DEFF Research Database (Denmark)

    Markvorsen, Steen; Palmer, V.

    2003-01-01

    We consider an m-dimensional minimal submanifold P and a metric R-sphere in the Euclidean space R-n. If the sphere has its center p on P, then it will cut out a well defined connected component of P which contains this center point. We call this connected component an extrinsic minimal R-ball of ...

  11. The role of time scales in extrinsic noise propagation

    Science.gov (United States)

    Iyer-Biswas, Srividya; Pedraza, Juan Manuel; Jayaprakash, C.

    2009-03-01

    Cell-to cell variability in the number of proteins has been studied extensively experimentally. There are many sources of this stochastic variability or noise that can be classified as intrinsic, due to the stochasticity of chemical reactions and extrinsic, due to environmental differences. The different stages in the production of proteins in response to a stimulus, the signaling cascade before transcription, transcription, and translation are characterized by different time scales. We analyze how these time scales determine the effect of the reactions at each stage on different sources of noise. For example, even if intrinsic noise dominates the fluctuations in mRNA number, for typical degradation rates, extrinsic noise can dominate corresponding protein number fluctuations. Such results are important in determining the importance of intrinsic noise at earlier stages of a genetic network on the products of subsequent stages. We examine cases in which the dynamics of the extrinsic noise can lead to differences from cases in which extrinsic noise arises from static (in time) cell-to-cell variations. We will interpret the experiments of Pedraza et al*. in the light of these results. *J. M. Pedraza et al, Science 25 March 2005:Vol. 307. no. 5717, pp. 1965 - 1969.

  12. Intrinsic and extrinsic contributions to stochasticity in gene expression

    Science.gov (United States)

    Swain, Peter S.; Elowitz, Michael B.; Siggia, Eric D.

    2002-10-01

    Gene expression is a stochastic, or "noisy," process. This noise comes about in two ways. The inherent stochasticity of biochemical processes such as transcription and translation generates "intrinsic" noise. In addition, fluctuations in the amounts or states of other cellular components lead indirectly to variation in the expression of a particular gene and thus represent "extrinsic" noise. Here, we show how the total variation in the level of expression of a given gene can be decomposed into its intrinsic and extrinsic components. We demonstrate theoretically that simultaneous measurement of two identical genes per cell enables discrimination of these two types of noise. Analytic expressions for intrinsic noise are given for a model that involves all the major steps in transcription and translation. These expressions give the sensitivity to various parameters, quantify the deviation from Poisson statistics, and provide a way of fitting experiment. Transcription dominates the intrinsic noise when the average number of proteins made per mRNA transcript is greater than 2. Below this number, translational effects also become important. Gene replication and cell division, included in the model, cause protein numbers to tend to a limit cycle. We calculate a general form for the extrinsic noise and illustrate it with the particular case of a single fluctuating extrinsic variablea repressor protein, which acts on the gene of interest. All results are confirmed by stochastic simulation using plausible parameters for Escherichia coli.

  13. A note on optical activity and extrinsic chirality

    CERN Document Server

    Arteaga, Oriol

    2015-01-01

    It has been assumed that optical activity can be measured by illuminating alternatively a material with left- and right- handed circular polarized light and analyzing the differential response. This simple and intuitive approach is in general incorrect, and has led to misleading idea that extrinsic chirality involves optical activity.

  14. VOL 6. NO. 1 2015 EXTRINSIC FACTORS THAT AFFECT ...

    African Journals Online (AJOL)

    Frederick Iraki

    The general objective of this study was to identify the extrinsic factors affect employee ... individual mechanisms that directly affect job performance in an organization(Colquitt, ... Benjamin (2010) posits that fringe benefits are significant and positive ... Mouly (2009) asserts that questionnaires add value to research because.

  15. Extrinsic Reinforcement in the Classroom: Bribery or Best Practice

    Science.gov (United States)

    Akin-Little, K. Angeleque; Eckert, Tanya L.; Lovett, Benjamin J.; Little, Steven G.

    2004-01-01

    The debate over the effects of the use of extrinsic reinforcement in classrooms, businesses, and societal settings has been occurring for over 30 years. Some theorists have cautioned against the use of reward, whereas others have found little, if any, detrimental effect. This article examines the debate with an emphasis on data-based findings. The…

  16. The Effects of Extrinsic Reinforcement on Intrinsic Motivation.

    Science.gov (United States)

    Blocker, Richard A.; Edwards, R. P.

    1982-01-01

    Discusses the role of extrinsic reinforcement in intrinsic motivation in cognitive attribution theory. Concludes that cognitive attribution theory lacks parsimony, in that extant reinforcement analysis can account for undermining with equal facility. Suggests undermining is of little significance due to its elusive and transient impact on operant…

  17. Extrinsic allergic alveolitis after exposure to the yeast Rhodotorula rubra.

    Science.gov (United States)

    Siersted, H C; Gravesen, S

    1993-05-01

    A case of extrinsic allergic alveolitis following exposure to the red yeast Rhodotorula rubra is reported--to our knowledge, for the first time. Extensive growth of the yeast in the patient's environment was demonstrated, explaining an elevated titer of Rhodotorula-specific precipitating antibodies in his serum. A bronchial provocation test confirmed the diagnosis.

  18. Visible Spectrum Circular Dichroism in Extrinsic Chirality Metamaterials

    CERN Document Server

    Lee, Seoungjun; Feng, Cheng; Jiao, Jiao; Khan, Ashfaq; Li, Lin

    2012-01-01

    We present the new planar extrinsic chirality metamaterial (ECM) design that manifests giant circular dichroism (CD) in the visible spectrum range rather than usual near-infrared and terahertz range. Effects of incident beam angles and meta-molecules unit sizes on the CD spectrums were theoretically analyzed; Physical mechanism was illustrated in new figures of asymmetrical current excitation in neighboring unit cells.

  19. The Impact of Extrinsic Demographic Factors on Cantonese Speech Acquisition

    Science.gov (United States)

    To, Carol K. S.; Cheung, Pamela S. P.; McLeod, Sharynne

    2013-01-01

    This study modeled the associations between extrinsic demographic factors and children's speech acquisition in Hong Kong Cantonese. The speech of 937 Cantonese-speaking children aged 2;4 to 6;7 in Hong Kong was assessed using a standardized speech test. Demographic information regarding household income, paternal education, maternal education,…

  20. The Effects of Extrinsic Rewards on Admissions Counselors' Performance

    Science.gov (United States)

    Gardner-Engel, Miriam

    2010-01-01

    This study examines the best ways to motivate college admissions counselors. A review of literature revealed multiple perspectives on intrinsic and extrinsic as well as tangible and intangible rewards. Primary research was designed to examine the impact of tangible rewards and verbal reinforcements with a convenience sample of nine college…

  1. Extrinsic Rewards and Intrinsic Motivation in Education: Reconsidered Once Again.

    Science.gov (United States)

    Deci, Edward L.; Koestner, Richard; Ryan, Richard M.

    2001-01-01

    Reviews the results of a meta analysis (E. Deci, R. Koestner, and R. Ryan, 1999) that shows that tangible extrinsic rewards do have a substantial undermining effect on intrinsic motivation. Discusses results, which support cognitive evaluation theory, in terms of their relevance for educational practice. (SLD)

  2. Extrinsic and Intrinsic Motivation at 30: Unresolved Scientific Issues

    Science.gov (United States)

    Reiss, Steven

    2005-01-01

    The undermining effect of extrinsic reward on intrinsic motivation remains unproven. The key unresolved issues are construct invalidity (all four definitions are unproved and two are illogical); measurement unreliability (the free-choice measure requires unreliable, subjective judgments to infer intrinsic motivation); inadequate experimental…

  3. Extrinsic Rewards and Intrinsic Motivation in Education: Reconsidered Once Again.

    Science.gov (United States)

    Deci, Edward L.; Koestner, Richard; Ryan, Richard M.

    2001-01-01

    Reviews the results of a meta analysis (E. Deci, R. Koestner, and R. Ryan, 1999) that shows that tangible extrinsic rewards do have a substantial undermining effect on intrinsic motivation. Discusses results, which support cognitive evaluation theory, in terms of their relevance for educational practice. (SLD)

  4. Extrinsic and Intrinsic Motivation at 30: Unresolved Scientific Issues

    Science.gov (United States)

    Reiss, Steven

    2005-01-01

    The undermining effect of extrinsic reward on intrinsic motivation remains unproven. The key unresolved issues are construct invalidity (all four definitions are unproved and two are illogical); measurement unreliability (the free-choice measure requires unreliable, subjective judgments to infer intrinsic motivation); inadequate experimental…

  5. Muscle fibre types of the lumbrical, interossei, flexor, and extensor muscles moving the index finger.

    Science.gov (United States)

    Hwang, Kun; Huan, Fan; Kim, Dae Joong

    2013-09-01

    The aim of this study was to determine the fibre types of the muscles moving the index fingers in humans. Fifteen forearms of eight adult cadavers were used. The sampled muscles were the first lumbrical (LM), first volar interosseous (VI), first dorsal interosseus (DI), second flexor digitorum profundus (FDP), second flexor digitorum superficialis (FDS), and extensor digitorum (ED). Six micrometer thick sections were stained for fast muscle fibres. The procedure was performed by applying mouse monoclonal anti-skeletal myosin antibody (fast) and avidin-biotin peroxidase complex staining. Rectangular areas (0.38 mm × 0.38 mm) were photographed and the boundaries of the muscle areas were marked on the translucent film. The numbers and sizes of the muscle fibres in each part were evaluated by the image analyser program and calculated per unit area (1 mm(2)). The proportion of the fast fibres was significantly (p = 0.012) greater in the intrinsic muscles (55.7 ± 17.1%) than in the extrinsic muscles (45.9 ± 17.1%). Among the six muscles, the VI had a significantly higher portion (59.3%) of fast fibres than the FDS (40.6%) (p = 0.005) or the FDP (45.1%) (p = 0.023). The density of the non-fast fibres was significantly (p = 0.015) greater in the extrinsic muscles (539.2 ± 336.8/mm(2)) than in the intrinsic muscles (383.4 ± 230.4/mm2). Since the non-fast fibres represent less fatigable fibres, it is thought that the extrinsic muscles have higher durability against fatigue, and the intrinsic muscles, including the LM, should move faster than the FDS or FDP because the MP joint should be flexed before the IP joint to grip an object.

  6. Distinguishing subtypes of extrinsic motivation among people with mild to borderline intellectual disability

    NARCIS (Netherlands)

    Frielink, N.; Schuengel, C.; Embregts, P.J.C.M.

    Background According to self-determination theory, motivation is ordered in types, including amotivation, extrinsic motivation and intrinsic motivation. Self-determination theory defines four subtypes of extrinsic motivation: external motivation, introjected motivation, identified motivation and

  7. Raldh expression in embryos of the direct developing frog Eleutherodactylus coqui and the conserved retinoic acid requirement for forelimb initiation.

    Science.gov (United States)

    Elinson, Richard P; Walton, Zachary; Nath, Kimberly

    2008-11-15

    Embryos of the direct developing frog, Eleutherodactylus coqui, provide opportunities to examine frog early limb development that are not available in species with tadpoles. We cloned two retinaldehyde dehydrogenase genes, EcRaldh1 and EcRaldh2, to see which enzyme likely supplies retinoic acid for limb development. EcRaldh1 is expressed in the dorsal retina, otic vesicle, pronephros, and pronephric duct, but not in the limb. EcRaldh2 is expressed early at the blastoporal lip and then in the mesoderm in the neurula, so this expression could function in forelimb initiation. Later EcRaldh2 is expressed in the mesoderm at the base of the limbs and in the ventral spinal cord where motor neurons innervating the limbs emerge. These observations on a frog support the functional conservation of EcRaldh2 in forelimb initiation in Osteichthyans and in limb patterning and motor neuron specification in tetrapods.

  8. Functional differentiation of trailing and leading forelimbs during locomotion on the ground and on a horizontal branch in the European red squirrel (Sciurus vulgaris, Rodentia).

    Science.gov (United States)

    Schmidt, André

    2011-06-01

    Mammalian locomotion is characterized by the frequent use of in-phase gaits in which the footfalls of the left and right fore- or hindlimbs are unevenly spaced in time. Although previous studies have identified a functional differentiation between the first limb (trailing limb) and the second limb (leading limb) to touch the ground during terrestrial locomotion, the influence of a horizontal branch on limb function has never been explored. To determine the functional differences between trailing and leading forelimbs during locomotion on the ground and on a horizontal branch, X-ray motion analysis and force measurements were carried out in two European red squirrels (Sciurus vulgaris, Rodentia). The differences observed between trailing and leading forelimbs were minimal during terrestrial locomotion, where both limbs fulfill two functions and go through a shock-absorbing phase followed by a generating phase. During locomotion on a horizontal branch, European red squirrels reduce speed and all substrate reaction forces transmitted may be due to the reduction of vertical oscillation of the center of mass. Further adjustments during locomotion on a horizontal branch differ significantly between trailing and leading forelimbs and include limb flexion, lead intervals, limb protraction and vertical displacement of the scapular pivot. Consequently, trailing and leading forelimbs perform different functions. Trailing forelimbs function primarily as shock-absorbing elements, whereas leading forelimbs are characterized by a high level of stiffness. This functional differentiation indicates that European red squirrels 'test' the substrate for stability with the trailing forelimb, while the leading forelimb responds to or counteracts swinging or snapping branches. Copyright © 2011 Elsevier GmbH. All rights reserved.

  9. Development of a skilled forelimb reach task in mice and the effects of C-8 projecting cortical spinal neuron ablation in motor learning by photothermal Au nanoparticles

    OpenAIRE

    Montenegro, Justin R.

    2015-01-01

    Motor learning is measured quantitatively through many behavioral tests. Behavioral models for motor learning observe skill acquisition and performance over a period of time within rodents. One such behavioral test is the skilled forelimb reach-to-grasp test. This skilled forelimb reach-to-grasp test has been extensively used to observe motor learning in behavioral studies and is an appropriate metric that can be used to asses experiments of the motor cortex. In this study, the skilled foreli...

  10. Shoulder girdle rotation, forelimb movement and the influence of carapace shape on locomotion in Testudo hermanni (Testudinidae).

    Science.gov (United States)

    Schmidt, Manuela; Mehlhorn, Martin; Fischer, Martin S

    2016-09-01

    Studies into the function of structures are crucial for making connections between morphology and behaviour of organisms, but are still rare for the terrestrial Testudinidae. We investigated the kinematics of shoulder girdle and forelimb motion in Hermann's tortoise Testudo hermanni using biplanar X-ray fluoroscopy with a twofold aim: firstly, to understand how the derived shapes of shoulder girdle and carapace together influence rotation of the girdle; and, secondly, to understand how girdle rotation affects forelimb excursion. The total degree of shoulder rotation in the horizontal plane is similar to a species with a less domed shell, but because of the long and nearly vertically oriented scapular prong, shoulder girdle rotation contributes more than 30% to the horizontal arc of the humerus and nearly 40% to the rotational component of step length. The antebrachium and manus, which act as a functional unit, contribute roughly 50% to this component of the step length because of their large excursion almost parallel to the mid-sagittal plane. This large excursion is the result of the complex interplay between humerus long-axis rotation, counter-rotation of the antebrachium, and elbow flexion and extension. A significant proportion of forelimb step length results from body translation that is due to the propulsive effect of the other limbs during their stance phases. Traits that are similar to other tortoises and terrestrial or semi-aquatic turtles are the overall slow walk because of a low stride frequency, and the lateral-sequence, diagonally coupled footfall pattern with high duty factors. Intraspecific variation of carapace shape and shoulder girdle dimensions has a corresponding effect on forelimb kinematics.

  11. Engagement in Classroom Learning: Creating Temporal Participation Incentives for Extrinsically Motivated Students through Bonus Credits

    Science.gov (United States)

    Rassuli, Ali

    2012-01-01

    Extrinsic inducements to adjust students' learning motivations have evolved within 2 opposing paradigms. Cognitive evaluation theories claim that controlling factors embedded in extrinsic rewards dissipate intrinsic aspirations. Behavioral theorists contend that if engagement is voluntary, extrinsic reinforcements enhance learning without ill…

  12. Engagement in Classroom Learning: Creating Temporal Participation Incentives for Extrinsically Motivated Students through Bonus Credits

    Science.gov (United States)

    Rassuli, Ali

    2012-01-01

    Extrinsic inducements to adjust students' learning motivations have evolved within 2 opposing paradigms. Cognitive evaluation theories claim that controlling factors embedded in extrinsic rewards dissipate intrinsic aspirations. Behavioral theorists contend that if engagement is voluntary, extrinsic reinforcements enhance learning without ill…

  13. Compensation aids skilled reaching in aging and in recovery from forelimb motor cortex stroke in the rat.

    Science.gov (United States)

    Alaverdashvili, M; Whishaw, I Q

    2010-04-28

    Compensatory movements mediate success in skilled reaching for food after stroke to the forelimb region of motor cortex (MtCx) in the rat. The present study asks whether the neural plasticity that enables compensation after motor stroke is preserved in aging. In order to avoid potential confounding effects of age-related negative-learning, rats were trained in a single pellet reaching task during young-adulthood. Subgroups were retested before and after contralateral forelimb MtCx stroke via pial stripping given at 3, 18, or 23 months of age. Over a two-month post-stroke rehabilitation period, end point measures were made of learned nonuse, recovery, retention, and performance ratings were made of reaching movement elements. Prior to stroke, young and aged rats maintained equivalent end point performance but older rats displayed compensatory changes in limb use as measured with ratings of the elements of forelimb movement. Following stroke, the aged groups of rats were more impaired on end point, movement, and anatomical measures. Nevertheless, the aged rats displayed substantial recovery via the use of compensatory movements. Thus, this study demonstrates that the neural plasticity that mediates compensatory movements after stroke in young adults is preserved prior to and following stroke in aging.

  14. Comparison of neuronal activities of external cuneate nucleus, spinocerebellar cortex and interpositus nucleus during passive movements of the rat's forelimb.

    Science.gov (United States)

    Casabona, A; Valle, M S; Bosco, G; Perciavalle, V

    2008-11-11

    In this paper we examined the neuronal activities of external cuneate nucleus, spinocerebellar Purkinje cells and interpositus nucleus during passive forelimb movements in anesthetized rats with the aim of identifying common or different patterns of activation across structures. By means of principal components analysis, we identified two main patterns of discharge which explained most of the dataset variance. One component characterized the movement-related activity of external cuneate and spinocerebellar cortical neurons, while the other reflected neuronal activity of the interpositus nucleus. We also found that both principal components were related to global forelimb kinematics but, while most of the variance of the activity of external cuneate cells and spinocerebellar Purkinje cells was explained by the limb axis orientation and orientation velocity, interpositus neurons' firing was best related to length and length velocity. This difference in the forelimb kinematics representation observed in external cuneate nucleus and spinocerebellar cortex compared with the interpositus nucleus is discussed with respect to the specific role that these structures may play also during active control of limb movements.

  15. Apparent density patterns in subchondral bone of the sloth and anteater forelimb.

    Science.gov (United States)

    Patel, Biren A; Carlson, Kristian J

    2008-10-23

    Vertebrate morphologists often are interested in inferring limb-loading patterns in animals characterized by different locomotor repertoires. Because bone apparent density (i.e. mass per unit volume of bone inclusive of porosities) is a determinant of compressive strength, and thus indicative of compressive loading, recent comparative studies in primates have proposed a structure-function relationship between apparent density of subchondral bone and locomotor behaviours that vary in compressive loading. If such patterns are found in other mammals, then these relationships would be strengthened further. Here, we examine the distal radius of suspensory sloths that generally load their forelimbs (FLs) in tension and of quadrupedal anteaters that generally load their FLs in compression. Computed tomography osteoabsorptiometry was used to visualize the patterns in subchondral apparent density. Suspensory sloths exhibit relatively smaller areas of high apparent density than quadrupedal anteaters. This locomotor-based pattern is analogous to the pattern observed in suspensory and quadrupedal primates. Similarity between xenarthran and primate trends suggests broad-scale applicability for analysing subchondral bone apparent density and supports the idea that bone functionally alters its material properties in response to locomotor behaviours.

  16. Generalized isoperimetric inequalities for extrinsic balls in minimal submanifolds

    DEFF Research Database (Denmark)

    Markvorsen, Steen; Palmer, Vicente

    2002-01-01

    The volume of an extrinsic ball in a minimal submanifold has a well defined lower bound when the ambient manifold has an upper bound on its sectional curvatures, see e.g. [2] and [10]. When this upper bound is non-positive, the second named author has shown an isoperimetric inequality for such do......The volume of an extrinsic ball in a minimal submanifold has a well defined lower bound when the ambient manifold has an upper bound on its sectional curvatures, see e.g. [2] and [10]. When this upper bound is non-positive, the second named author has shown an isoperimetric inequality...... for such domains, see [11]. This result again gives the comparison result for volumes alluded to above together with a characterization of the totally geodesic submanifolds of hyperbolic space forms. In the present paper we find a corresponding sharp isoperimetric inequality for minimal submanifolds in spaces...

  17. [Actualities in extrinsic allergic alveolities or hypersensitivity pneumonitis].

    Science.gov (United States)

    Ndiaye, M; Soumah, M; Sow, M L

    2007-01-01

    Significant advances have been noticed in the pathogenesis and the diagnosis of extrinsic allergic alveolitis during the last few years. Indeed the immune mechanism and the enabling conditions have been more precisely defined, the clinical stages and the diagnosis criterias clearly defined, new antigens incriminated and some etiological agents have been reclassified. The present pathogenic explanation insists on the type IV hypersensitivity reaction with sensitization of T lymphocytes, activation macrophages, the formation of IgG type antibodies and immune complexes, activation of complement and secretion of cytokines. The involvement of certain HLA classes (HLA2, DR3, DRB1, DQB1), interaction of genetics and environments factors, the role of infections agents and smoking have been demonstrated in several studies. The development of news clinical and biological diagnosis criteria have led the discovery of new extrinsic allergic alveolitis in the work places, a better knowledge of the prognostic elements and an appropriate adaptation of prevention measures.

  18. Implications on the cosmic coincidence by a dynamical extrinsic curvature

    CERN Document Server

    Capistrano, A J S

    2015-01-01

    In this work, we apply the smooth deformation concept in order to obtain a modification of Friedmann equations. It is shown that the cosmic coincidence can be at least alleviated using the dynamical properties of the extrinsic curvature. We investigate the transition from nucleosynthesis to the coincidence era obtaining a very small variation of the ratio $r=\\frac{\\rho_{m}}{\\rho_{ext}}$, that compares the matter energy density to extrinsic energy density, compatible with the known behavior of the deceleration parameter. We also show that the calculated "equivalence" redshift matches the transition redshift from a deceleration to accelerated phase and the coincidence ceases to be. The dynamics on $r$ is also studied based on Hubble parameter observations as the latest Baryons Acoustic Oscillations/Cosmic Microwave Background Radiation (BAO/CMBR) + SNIa.

  19. Spotlight on the diagnosis of extrinsic allergic alveolitis (hypersensitivity pneumonitis).

    Science.gov (United States)

    Baur, Xaver; Fischer, Axel; Budnik, Lygia T

    2015-01-01

    Repeated inhalative exposures to antigenic material from a variety of sources, mainly from moulds, thermophilic Actinomycetes, and avians, respectively, can induce immune responses with the clinical picture of extrinsic allergic alveolitis (EAA) or hypersensitivity pneumonitis. Delays of years or even decades till the diagnosis is made are not uncommon; frequent misdiagnoses include allergic asthma, COPD, recurrent flue and other infections. We provide here the state of the art references, a detailed case description and recommend a current diagnostics schema.

  20. Extrinsic allergic alveolitis with IgA deficiency.

    Science.gov (United States)

    Sennekamp, J; Morr, H; Behr, J

    2004-12-22

    Up to now only 3 cases of extrinsic allergic alveolitis (hypersensitivity pneumonitis) with IgA deficiency have been published worldwide. We had the opportunity to detect two additional cases which will be presented here. Summarizing all cases IgA deficiency is a risk factor for a severe course of the disease and an increased susceptibility to acquire allergic alveolitis by low dose antigen exposure.

  1. Mathematical Model of Extrinsic Blood Coagulation Cascade Dynamic System

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The blood coagulation system is very important to life. This paper presents a mathematical blood coagulation model for the extrinsic pathway. This model simulates clotting factor VIII, which plays an important role in the coagulation mechanism. The mathematical model is used to study the equilibrium stability, orbit structure, attractors and global stability behavior, with conclusions in accordance with the physiological phenomena. Moreover, the results provide information about blood related illnesses, which can be used for further study of the coagulation mechanism.

  2. Interactional Motivation in Artificial Systems: Between Extrinsic and Intrinsic Motivation

    OpenAIRE

    Georgeon, Olivier; Marshall, James; Gay, Simon

    2012-01-01

    International audience; This paper introduces Interactional Motivation (IM) as a way to implement self-motivation in artificial systems. An interactionally motivated agent selects behaviors for the sake of enacting the behavior itself rather than for the value of the behavior’s outcome. IM contrasts with extrinsic motivation by the fact that it defines the agent’s motivation independently from the environment’s state. Because IM does not refer to the environment’s states, we argue that IM is ...

  3. Extrinsic and intrinsic CPT asymmetries in neutrino oscillations

    Directory of Open Access Journals (Sweden)

    Tommy Ohlsson

    2015-04-01

    Full Text Available We reconsider the extrinsic and possible intrinsic CPT violation in neutrino oscillations, and point out an identity, i.e., AαβCP=AβαCPT+AαβT, among the CP, T, and CPT asymmetries in oscillations. For three-flavor oscillations in matter of constant density, the extrinsic CPT asymmetries AeeCPT, AeμCPT, AμeCPT, and AμμCPT caused by Earth matter effects have been calculated in the plane of different neutrino energies and baseline lengths. It is found that two analytical conditions can be implemented to describe the main structure of the contours of vanishing extrinsic CPT asymmetries. Finally, without assuming intrinsic CPT symmetry in the neutrino sector, we investigate the possibility to constrain the difference of the neutrino CP-violating phase δ and the antineutrino one δ¯ using a low-energy neutrino factory and the super-beam experiment ESSνSB. We find that |δ−δ¯|≲0.35π in the former case and |δ−δ¯|≲0.7π in the latter case can be achieved at the 3σ confidence level if δ=δ¯=π/2 is assumed.

  4. Are competition and extrinsic motivation reliable predictors of academic cheating?

    Directory of Open Access Journals (Sweden)

    Gábor eOrosz

    2013-02-01

    Full Text Available Previous studies suggest that extrinsic motivation and competition are reliable predictors of academic cheating. The aim of the present questionnaire study was to separate the effects of motivation- and competition-related variables on academic cheating by Hungarian high school students (N = 620, M = 264, F = 356. Structural equation modeling showed that intrinsic motivation has a negative effect, and amotivation has a positive indirect effect on self-reported academic cheating. In contrast, extrinsic motivation had no significant effect. Indirect positive influence on cheating, based on some characteristics of hypercompetition, was also found, whereas attitudes towards self-developmental competition had a mediated negative influence. Neither constructive nor destructive competitive classroom climate had a significant impact on academic dishonesty. Acceptance of cheating and guilt has significant and direct effect on self-reported cheating. In comparison with them, the effects of motivational and competition-related variables are relatively small, even negligible. These results suggest that extrinsic motivation and competition are not amongst the most reliable predictors of academic cheating behavior.

  5. Effects of empathic paraphrasing - Extrinsic emotion regulation in social conflict

    Directory of Open Access Journals (Sweden)

    Maria eSeehausen

    2012-11-01

    Full Text Available In the present study, we investigated the effects of empathic paraphrasing as an extrinsic emotion regulation technique in social conflict. We hypothesized that negative emotions elicited by social conflict can be regulated extrinsically in a conversation by a listener following the narrator’s perspective and verbally expressing cognitive empathy.20 participants were interviewed on an ongoing or recently self-experienced social conflict. The interviewer utilized ten standardized open questions inviting participants to describe their perception of the conflict. After each of the ten descriptions, the interviewer responded by either paraphrasing or taking notes (control condition. Valence ratings pertaining to the current emotional state were assessed during the interview along with psychophysiological and voice recordings.Participants reported feeling less negative after hearing the interviewer paraphrase what they had said. In addition, we found a lower sound intensity of participants' voices when answering to questions following a paraphrase. At the physiological level, skin conductance response, as well as heart rate, was higher during paraphrasing than during taking notes, while blood volume pulse amplitude was lower during paraphrasing, indicating higher autonomic arousal.The results show that demonstrating cognitive empathy through paraphrasing can extrinsically regulate negative emotion on a short-term basis. Paraphrasing led to enhanced autonomic activation in recipients, while at the same time influencing emotional valence in the direction of feeling better. A possible explanation for these results is that being treated in an empathic manner may stimulate a more intense emotion processing helping to transform and resolve the conflict.

  6. Extrinsic Calibration of Camera Networks Based on Pedestrians.

    Science.gov (United States)

    Guan, Junzhi; Deboeverie, Francis; Slembrouck, Maarten; Van Haerenborgh, Dirk; Van Cauwelaert, Dimitri; Veelaert, Peter; Philips, Wilfried

    2016-05-09

    In this paper, we propose a novel extrinsic calibration method for camera networks by analyzing tracks of pedestrians. First of all, we extract the center lines of walking persons by detecting their heads and feet in the camera images. We propose an easy and accurate method to estimate the 3D positions of the head and feet w.r.t. a local camera coordinate system from these center lines. We also propose a RANSAC-based orthogonal Procrustes approach to compute relative extrinsic parameters connecting the coordinate systems of cameras in a pairwise fashion. Finally, we refine the extrinsic calibration matrices using a method that minimizes the reprojection error. While existing state-of-the-art calibration methods explore epipolar geometry and use image positions directly, the proposed method first computes 3D positions per camera and then fuses the data. This results in simpler computations and a more flexible and accurate calibration method. Another advantage of our method is that it can also handle the case of persons walking along straight lines, which cannot be handled by most of the existing state-of-the-art calibration methods since all head and feet positions are co-planar. This situation often happens in real life.

  7. Are competition and extrinsic motivation reliable predictors of academic cheating?

    Science.gov (United States)

    Orosz, Gábor; Farkas, Dávid; Roland-Lévy, Christine

    2013-01-01

    Previous studies suggest that extrinsic motivation and competition are reliable predictors of academic cheating. The aim of the present questionnaire study was to separate the effects of motivation- and competition-related variables on academic cheating by Hungarian high school students (N = 620, M = 264, F = 356). Structural equation modeling showed that intrinsic motivation has a negative effect, and amotivation has a positive indirect effect on self-reported academic cheating. In contrast, extrinsic motivation had no significant effect. Indirect positive influence on cheating, based on some characteristics of hypercompetition, was also found, whereas attitudes toward self-developmental competition had a mediated negative influence. Neither constructive nor destructive competitive classroom climate had a significant impact on academic dishonesty. Acceptance of cheating and guilt has significant and direct effect on self-reported cheating. In comparison with them, the effects of motivational and competition-related variables are relatively small, even negligible. These results suggest that extrinsic motivation and competition are not amongst the most reliable predictors of academic cheating behavior.

  8. Stochastic synchronization of neuronal populations with intrinsic and extrinsic noise.

    KAUST Repository

    Bressloff, Paul C

    2011-05-03

    We extend the theory of noise-induced phase synchronization to the case of a neural master equation describing the stochastic dynamics of an ensemble of uncoupled neuronal population oscillators with intrinsic and extrinsic noise. The master equation formulation of stochastic neurodynamics represents the state of each population by the number of currently active neurons, and the state transitions are chosen so that deterministic Wilson-Cowan rate equations are recovered in the mean-field limit. We apply phase reduction and averaging methods to a corresponding Langevin approximation of the master equation in order to determine how intrinsic noise disrupts synchronization of the population oscillators driven by a common extrinsic noise source. We illustrate our analysis by considering one of the simplest networks known to generate limit cycle oscillations at the population level, namely, a pair of mutually coupled excitatory (E) and inhibitory (I) subpopulations. We show how the combination of intrinsic independent noise and extrinsic common noise can lead to clustering of the population oscillators due to the multiplicative nature of both noise sources under the Langevin approximation. Finally, we show how a similar analysis can be carried out for another simple population model that exhibits limit cycle oscillations in the deterministic limit, namely, a recurrent excitatory network with synaptic depression; inclusion of synaptic depression into the neural master equation now generates a stochastic hybrid system.

  9. Acquired muscle contractures in the dog and cat. A review of the literature and case report.

    Science.gov (United States)

    Taylor, J; Tangner, C H

    2007-01-01

    Canine and feline muscle contracture is reported to affect several different muscles, is associated with a number of predisposing factors, and a varying prognosis depending upon which muscle is affected. Most patients suffer some form of trauma weeks to months before the contracture is present. The clinical signs include: lameness, pain, weakness, decreased range of motion, a firmness noted throughout the entire muscle, and usually a characteristic gait. Pre-disposing factors for muscle contracture include: compartment syndrome, infection, trauma, repetitive strains, fractures, infectious diseases, immune-mediated diseases, neoplasia, and ischaemia. There does appear to be some breed and age predilection, however, the sex of the animal does not have an appreciable influence. In general, muscle contractures of the forelimb respond better to treatment and carry a better prognosis than muscle contractures of the hindlimb.

  10. Sub-acute and chronic MRI findings in bilateral canine fibrotic contracture of the infraspinatus muscle.

    Science.gov (United States)

    Orellana-James, N G; Ginja, M M; Regueiro, M; Oliveira, P; Gama, A; Rodriguez-Altonaga, J A; Gonzalo-Orden, J M

    2013-08-01

    A six-year-old, 30-kg female German pointer dog was presented for examination with a history of pre-existing right-forelimb lameness and more recent (3 months) persistent lameness in the left-forelimb. Physical examination revealed mild left-forelimb lameness and a mild circumduction movement. There were no signs of pain or crepitation detected during manipulation of the shoulders, but the animal was unable to fully flex both glenohumeral joints. Magnetic resonance imaging, using fast recovery fast spin echo T2-weighted and fat saturated proton density sequences, revealed abnormal heterogeneous hypointensity in the right infraspinatus muscle and a heterogeneous hyperintense area in the left infraspinatus muscle. Surgical treatment consisting of a bilateral infraspinatus tenectomy resulted in improved limb function. Histopathological examination demonstrated tissue changes in the right infraspinatus, characterised by myofibre degeneration and fibrosis, compatible with a chronic degenerative process, while changes in the left infraspinatus muscle were characterised by variable degrees of fibre degeneration, haemorrhage and interstitial oedema. © 2013 British Small Animal Veterinary Association.

  11. Resting Orientations of Dinosaur Scapulae and Forelimbs: A Numerical Analysis, with Implications for Reconstructions and Museum Mounts.

    Science.gov (United States)

    Senter, Phil; Robins, James H

    2015-01-01

    The inclination of the scapular blade and the resting pose of the forelimb in dinosaurs differ among reconstructions and among skeletal mounts. For most dinosaurian taxa, no attempt has previously been made to quantify the correct resting positions of these elements. Here, we used data from skeletons preserved in articulation to quantify the resting orientations of the scapula and forelimb in dinosaurs. Specimens were included in the study only if they were preserved lying on their sides; for each specimen the angle between forelimb bones at a given joint was included in the analysis only if the joint was preserved in articulation. Using correlation analyses of the angles between the long axis of the sacrum, the first dorsal centrum, and the scapular blade in theropods and Eoraptor, we found that vertebral hyperextension does not influence scapular orientation in saurischians. Among examined taxa, the long axis of the scapular blade was found to be most horizontal in bipedal saurischians, most vertical in basal ornithopods, and intermediate in hadrosauroids. We found that in bipedal dinosaurs other than theropods with semilunate carpals, the resting orientation of the elbow is close to a right angle and the resting orientation of the wrist is such that the hand exhibits only slight ulnar deviation from the antebrachium. In theropods with semilunate carpals the elbow and wrist are more flexed at rest, with the elbow at a strongly acute angle and with the wrist approximately at a right angle. The results of our study have important implications for correct orientations of bones in reconstructions and skeletal mounts. Here, we provide recommendations on bone orientations based on our results.

  12. Effect of hoof boots and toe-extension shoes on the forelimb kinetics of horses during walking.

    Science.gov (United States)

    Amitrano, Fernando N; Gutierrez-Nibeyro, Santiago D; Schaeffer, David J

    2016-05-01

    OBJECTIVE To determine and compare the effect of hoof boots (HBs) and shoes with a toe extension on stance duration, ground reaction force, and sole length in contact with the ground in nonlame horses during walking. ANIMALS 6 nonlame Standardbreds. PROCEDURES Force plate gait analyses of the forelimbs were performed while the horses were walking barefoot before manipulation of feet (baseline), while the horses were walking fitted with HBs, while the horses were walking shod with toe-extension shoes, and while the horses were walking barefoot after shoe removal. Horses underwent radiography of both forelimb feet to determine the sole length in contact with the ground when barefoot, wearing HBs, and shod with toe-extension shoes. Stance duration, ground reaction force, and sole length were compared among the various walking sessions. RESULTS Compared with baseline findings, stance duration increased significantly when horses were fitted with HBs (7%) or toe-extension shoes (5%). Peak forelimb ground reaction force was similar among walking sessions; however, time of braking force peak was significantly greater during the stance phase only when horses wore HBs. Also, the sole length in contact with the ground was significantly longer in horses fitted with HBs (14.3 cm) or shod with the toe-extension shoes (17.6 cm), compared with that for one of the barefoot hooves (12.7 cm). CONCLUSIONS AND CLINICAL RELEVANCE In nonlame horses, use of HBs prolonged the stance time and time of braking force peak, which is indicative of a slower deceleration phase during limb impact with the ground. Also, the use of HBs prolonged the deceleration phase of the stride and increased the sole length in contact with the ground.

  13. Resting Orientations of Dinosaur Scapulae and Forelimbs: A Numerical Analysis, with Implications for Reconstructions and Museum Mounts.

    Directory of Open Access Journals (Sweden)

    Phil Senter

    Full Text Available The inclination of the scapular blade and the resting pose of the forelimb in dinosaurs differ among reconstructions and among skeletal mounts. For most dinosaurian taxa, no attempt has previously been made to quantify the correct resting positions of these elements. Here, we used data from skeletons preserved in articulation to quantify the resting orientations of the scapula and forelimb in dinosaurs. Specimens were included in the study only if they were preserved lying on their sides; for each specimen the angle between forelimb bones at a given joint was included in the analysis only if the joint was preserved in articulation. Using correlation analyses of the angles between the long axis of the sacrum, the first dorsal centrum, and the scapular blade in theropods and Eoraptor, we found that vertebral hyperextension does not influence scapular orientation in saurischians. Among examined taxa, the long axis of the scapular blade was found to be most horizontal in bipedal saurischians, most vertical in basal ornithopods, and intermediate in hadrosauroids. We found that in bipedal dinosaurs other than theropods with semilunate carpals, the resting orientation of the elbow is close to a right angle and the resting orientation of the wrist is such that the hand exhibits only slight ulnar deviation from the antebrachium. In theropods with semilunate carpals the elbow and wrist are more flexed at rest, with the elbow at a strongly acute angle and with the wrist approximately at a right angle. The results of our study have important implications for correct orientations of bones in reconstructions and skeletal mounts. Here, we provide recommendations on bone orientations based on our results.

  14. Activation and intermuscular coherence of distal arm muscles during proximal muscle contraction.

    Science.gov (United States)

    Lee, Sang Wook; Landers, Katlin; Harris-Love, Michelle L

    2014-03-01

    In the human upper extremity (UE), unintended effects of proximal muscle activation on muscles controlling the hand could be an important aspect of motor control due to the necessary coordination of distal and proximal segments during functional activities. This study aimed to elucidate the effects of concurrent activation of elbow muscles on the coordination between hand muscles performing a grip task. Eleven healthy subjects performed precision grip tasks while a constant extension or flexion moment was applied to their elbow joints, inducing a sustained submaximal contraction of elbow muscles to counter the applied torque. Activation of four hand muscles was measured during each task condition using surface electromyography (EMG). When concurrent activation of elbow muscles was induced, significant changes in the activation levels of the hand muscles were observed, with greater effects on the extrinsic finger extensor (23.2 % increase under 30 % elbow extensor activation; p = 0.003) than extrinsic finger flexor (14.2 % increase under 30 % elbow flexor activation; p = 0.130). Elbow muscle activation also induced involuntary changes in the intrinsic thumb flexor activation (44.6 % increase under 30 % elbow extensor activation; p = 0.005). EMG-EMG coherence analyses revealed that elbow muscle activation significantly reduced intermuscular coherence between distal muscle pairs, with its greatest effects on coherence in the β-band (13-25 Hz) (average of 17 % decrease under 30 % elbow flexor activation). The results of this study provide evidence for involuntary, muscle-specific interactions between distal and proximal UE muscles, which may contribute to UE motor performance in health and disease.

  15. Muscle Disorders

    Science.gov (United States)

    Your muscles help you move and help your body work. Different types of muscles have different jobs. There are many problems that can affect muscles. Muscle disorders can cause weakness, pain or even ...

  16. Muscle Cramps

    Science.gov (United States)

    Muscle cramps are sudden, involuntary contractions or spasms in one or more of your muscles. They often occur ... minutes. It is a very common muscle problem. Muscle cramps can be caused by nerves that malfunction. Sometimes ...

  17. The influence of extrinsic motivation on competition-based selection.

    Science.gov (United States)

    Sänger, Jessica; Wascher, Edmund

    2011-10-10

    The biased competition approach to visuo-spatial attention proposes that the selection of competing information is effected by the saliency of the stimulus as well as by an intention-based bias of attention towards behavioural goals. Wascher and Beste (2010) [32] showed that the detection of relevant information depends on its relative saliency compared to irrelevant conflicting stimuli. Furthermore the N1pc, N2pc and N2 of the EEG varied with the strength of the conflict. However, this system could also be modulated by rather global mechanisms like attentional effort. The present study investigates such modulations by testing the influence of extrinsic motivation on the selection of competing stimuli. Participants had to detect a luminance change in various conditions among others against an irrelevant orientation change. Half of the participants were motivated to maximize their performance by the announcement of a monetary reward for correct responses. Participants who were motivated had lower error rates than participants who were not motivated. The event-related lateralizations of the EEG showed no motivation-related effect on the N1pc, which reflects the initial saliency driven orientation of attention towards the more salient stimulus. The subsequent N2pc was enhanced in the motivation condition. Extrinsic motivation was also accompanied by enhanced fronto-central negativities. Thus, the data provide evidence that the improvement of selection performance when participants were extrinsically motivated by announcing a reward was not due to changes in the initial saliency based processing of information but was foremost mediated by improved higher-level mechanisms.

  18. Extrinsic allergic alveolitis: a disease commoner in non-smokers.

    Science.gov (United States)

    Warren, C P

    1977-01-01

    The smoking habits of 18 patients with extrinsic allergic alveolitis, 22 with cryptogenic fibrosing alveolitis, and 75 patients with sarcoidosis were compared with the smoking habits of the normal population of the Prairie Region for 1973. The patients were diagnosed at the same two hospitals over the four-year period November 1971--75 and were of comparable age. Non-smoking was significantly associated with allergic alveolitis in men and the three cases in women were all non-smokers. For the other two diseases, smoking habits were similar to those of the local population. PMID:594937

  19. [Extrinsic allergic alveolitis: a review for the practitioner].

    Science.gov (United States)

    Pralong, G; Leuenberger, P

    1998-08-22

    Extrinsic allergic alveolitis (EAA) or hypersensitivity pneumonitis (HP) is a clinical syndrome characterised by an inflammatory, partly granulomatous, immune disorder involving interstitial and alveolar spaces secondary to inhalation of organic substances. The disorder is mainly due to occupational exposure, farmer's lung being the best-known example. Acute, subacute or chronic forms can be clinically differentiated. Given the fact that chronic forms may present a pattern of irreversible pulmonary fibrosis, clinicians must be aware of the diagnosis of EAA in every situation where the history shows a potential antigenic exposure. Prevention should be reinforced by increasing individual protective measures and by improving techniques used at the workplace.

  20. Extrinsic sound stimulations and development of periphery auditory synapses

    Institute of Scientific and Technical Information of China (English)

    Kun Hou; Shiming Yang; Ke Liu

    2015-01-01

    The development of auditory synapses is a key process for the maturation of hearing function. However, it is still on debate regarding whether the development of auditory synapses is dominated by acquired sound stimulations. In this review, we summarize relevant publications in recent decades to address this issue. Most reported data suggest that extrinsic sound stimulations do affect, but not govern the development of periphery auditory synapses. Overall, periphery auditory synapses develop and mature according to its intrinsic mechanism to build up the synaptic connections between sensory neurons and/or interneurons.

  1. Spectral dependences of extrinsic optical absorption in sillenite crystals

    Energy Technology Data Exchange (ETDEWEB)

    Kisteneva, M G; Khudyakova, E S; Shandarov, S M; Akrestina, A S; Dyu, V G [Tomsk State University of Control Systems and Radioelectronics, Tomsk (Russian Federation); Kargin, Yu F [A.A.Baikov Institute of Metallurgy and Materials Science, Russian Academy of Sciences, Moscow (Russian Federation)

    2015-07-31

    The influence of laser irradiation at wavelengths of 532 and 655 nm and annealing in air at temperatures from 200 to 370 °C on optical absorption spectra of undoped bismuth silicon oxide and bismuth germanium oxide and aluminium-doped bismuth titanium oxide crystals has been studied experimentally. The experimental data have been interpreted in terms of a model for extrinsic absorption that takes into account not only the contribution of the photoexcitation of electrons from deep donor centres with a normal distribution of their concentration with respect to ionisation energy but also that of intracentre transitions. (laser applications and other topics in quantum electronics)

  2. Older adults' intrinsic and extrinsic motivation toward physical activity.

    Science.gov (United States)

    Dacey, Marie; Baltzell, Amy; Zaichkowsky, Len

    2008-01-01

    To examine how motives discriminate 3 physical activity levels of inactive, active, and sustained maintainers. Six hundred forty-five adults (M age = 63.8) completed stage-of-change and Exercise Motivations Inventory (EMI-2) scales. Exploratory factor analysis established psychometric properties of the EMI-2 suitable for older adults. Six factors emerged in the EMI-2: health and fitness, social/emotional benefits, weight management, stress management, enjoyment, and appearance. Enjoyment contributed most to differentiating activity levels. Moderators of age and gender were delineated. Intrinsic motivation and self-determined extrinsic motivation distinguish older adults' activity levels.

  3. Gap junction blockers attenuate beta oscillations and improve forelimb function in hemiparkinsonian rats.

    Science.gov (United States)

    Phookan, Sujoy; Sutton, Alexander C; Walling, Ian; Smith, Autumn; O'Connor, Katherine A; Campbell, Joannalee C; Calos, Megan; Yu, Wilson; Pilitsis, Julie G; Brotchie, Jonathan M; Shin, Damian S

    2015-03-01

    /kg) into hemiparkinsonian rats which attenuated dominant β oscillations in the right GPe and also improved left forepaw akinesia in the step test. Conversely, direct injection of TMA into the right GPe of naive rats induced contralateral left forelimb akinesia. Overall, our results suggest that GJs contribute to β oscillations in the GPe of hemiparkinsonian rats. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. TURBO DECODER USING LOCAL SUBSIDIARY MAXIMUM LIKELIHOOD DECODING IN PRIOR ESTIMATION OF THE EXTRINSIC INFORMATION

    Institute of Scientific and Technical Information of China (English)

    Yang Fengfan

    2004-01-01

    A new technique for turbo decoder is proposed by using a local subsidiary maximum likelihood decoding and a probability distributions family for the extrinsic information. The optimal distribution of the extrinsic information is dynamically specified for each component decoder.The simulation results show that the iterative decoder with the new technique outperforms that of the decoder with the traditional Gaussian approach for the extrinsic information under the same conditions.

  5. Intrinsic and Extrinsic Science: A Dialectic of Scientific Fame.

    Science.gov (United States)

    Feist, Gregory J

    2016-11-01

    In this article, I argue that scientific fame and impact exists on a continuum from the mundane to the transformative/revolutionary. Ideally, one achieves fame and impact in science by synthesizing two extreme career prototypes: intrinsic and extrinsic research. The former is guided by interest, curiosity, passion, gut, and intuition for important untapped topics. The latter is guided by money, grants, and/or what is being published in top-tier journals. Assessment of fame and impact in science ultimately rests on productivity (publication) and some variation of its impact (citations). In addition to those traditional measures of impact, there are some relatively new metrics (e.g., the h index and altmetrics). If psychology is to achieve consensual cumulative progress and better rates of replication, I propose that upcoming psychologists would do well to understand that success is not equal to fame and that individual career success is not necessarily the same as disciplinary success. Finally, if one is to have a successful and perhaps even famous career in psychological science, a good strategy would be to synthesize intrinsic and extrinsic motives for one's research.

  6. The effect of extrinsic attributes on liking of cottage cheese.

    Science.gov (United States)

    Hubbard, E M; Jervis, S M; Drake, M A

    2016-01-01

    Preference mapping studies with cottage cheese have demonstrated that cottage cheese liking is influenced by flavor, texture, curd size, and dressing content. However, extrinsic factors such as package, label claims, and brand name may also influence liking and have not been studied. The objective of this study was to evaluate the role of package attributes and brand on the liking of cottage cheese. A conjoint survey with Kano analysis (n=460) was conducted to explore the effect of extrinsic attributes (brand, label claim, milkfat content, and price) on liking. Following the survey, 150 consumers evaluated intrinsic attributes of 7 cottage cheeses with and without brand information in a 2-d crossover design. Results were evaluated by 2-way ANOVA and multivariate analyses. Milkfat content and price had the highest influence on liking by conjoint analysis. Cottage cheese with 2% milkfat and a low price was preferred. Specific label claims such as "excellent source of calcium (>10%)" were more attractive to consumers than "low sodium" or "extra creamy." Branding influenced overall liking and purchase intent for cottage cheeses to differing degrees. For national brands, acceptance scores were enhanced in the presence of the brand. An all-natural claim was more appealing than organic by conjoint analysis and this result was also confirmed with consumer acceptance testing. Findings from this study can help manufacturers, as well as food marketers, better target their products and brands with attributes that drive consumer choice.

  7. Extrinsic labelling of zinc and calcium in bread

    Energy Technology Data Exchange (ETDEWEB)

    Fredlund, Kerstin E-mail: mlw@fsc.chalmers.se; Rossander-Hulthen, Lena; Isaksson, Mats; Almgren, Annette; Sandberg, A.-S

    2002-08-01

    This study investigated the effect of different means of extrinsic administration of {sup 65}Zn and {sup 47}Ca in white wheat flour bread on the measured absorption. Eight healthy subjects were served 80 g of labelled bread as a standardized breakfast after an overnight fast on three occasions. Extrinsic labelling of the meals with {sup 65}Zn and {sup 47}Ca was done in three ways: (a) by adding the isotopes to the bread 16 h before it was served, (b) by adding the isotopes shortly before serving or (c) by adding the isotopes to the water used in dough making. Zinc and calcium chloride corresponding to 3.2 mg (49 {mu}mol) zinc and 275 mg (6.9 mmol) calcium in one portion were added to the dough. Whole-body retention was measured by whole-body counting. The fractional absorption of zinc was (a) 0.243{+-}0.122, (b) 0.217{+-}0.101 and (c) 0.178{+-}0.063 (mean{+-}SD), and the fractional absorption of calcium (expressed as calcium retention on day 7) was (a) 0.351{+-}0.108, (b) 0.357{+-}0.131 and (c) 0.334{+-}0.117 (mean{+-}SD). No significant difference (p>0.05) was seen between the different ways for either zinc nor calcium.

  8. In/extrinsic granularity in superconducting boron-doped diamond

    Energy Technology Data Exchange (ETDEWEB)

    Willems, B.L. [INPAC - Institute for Nanoscale Physics and Chemistry, Katholieke Universiteit Leuven, Celestijnenlaan 200D, B - 3001 Leuven (Belgium); Facultad de Ciencias Fisicas, Universidad Nacional Mayor de San Marcos, P.O. 14-0149, Lima-14 (Peru); Zhang, G. [INPAC - Institute for Nanoscale Physics and Chemistry, Katholieke Universiteit Leuven, Celestijnenlaan 200D, B - 3001 Leuven (Belgium); Vanacken, J., E-mail: johan.vanacken@fys.kuleuven.b [INPAC - Institute for Nanoscale Physics and Chemistry, Katholieke Universiteit Leuven, Celestijnenlaan 200D, B - 3001 Leuven (Belgium); Moshchalkov, V.V. [INPAC - Institute for Nanoscale Physics and Chemistry, Katholieke Universiteit Leuven, Celestijnenlaan 200D, B - 3001 Leuven (Belgium); Guillamon, I.; Suderow, H.; Vieira, S. [Laboratorio de Bajas Temperaturas, Departamento de Fisica de la Materia Condensada, Universidad Autonoma de Madrid (Spain); Janssens, S.D. [Hasselt University, Institute for Materials Research, Wetenschapspark 1, B-3590 Diepenbeek (Belgium); Haenen, K.; Wagner, P. [Hasselt University, Institute for Materials Research, Wetenschapspark 1, B-3590 Diepenbeek (Belgium); Division IMOMEC, IMEC vzw, Wetenschapspark 1, B-3590 Diepenbeek (Belgium)

    2010-10-01

    When charge carriers are introduced in diamond, e.g. by chemical doping with Boron (B), the C{sub 1-x}B{sub x} diamond:B can exhibit an insulator-to-metal transition (p{sub Mott{approx}}2x10{sup 20}cm{sup -3}). Under even heavier boron doping (n{sub B{approx}}10{sup 21}cm{sup -3}), diamond becomes superconducting. Using microwave plasma-assisted chemical vapor deposition (MPCVD) we have prepared diamond:B thin films with critical offset temperatures T{sub C} below 3 K. We have investigated the transport properties of these diamond:B thin films, which show pronounced granular effects. It turns out, that this granularity is both intrinsic as well as extrinsic. The extrinsic granularity is the effect of the growth method which needs to start from a seeding of the substrate with detonation nanodiamond, which acts as nucleation centers for further MPCVD growth of the film. In using SPM/STM techniques, we also observed intrinsic granularity, meaning that within physical grains, we observe also a strong intragrain modulation of the order parameter. As a consequence of these granularities, the transport properties show evidence of (i) strong superconducting fluctuations and (ii) Cooper pair tunneling and/or quasiparticle tunneling. The latter effects explain the observed negative magnetoresistance.

  9. Intrinsic and extrinsic influences on children's acceptance of new foods.

    Science.gov (United States)

    Blissett, Jackie; Fogel, Anna

    2013-09-10

    The foods that tend to be rejected by children include those which may have greatest importance for later health. This paper reviews some of the intrinsic and extrinsic influences on preschool children's eating behavior, with particular reference to their acceptance of new foods into their diet. Factors conceptualized as intrinsic to the child in this review include sensory processing, taste perception, neophobia, and temperament. The important extrinsic determinants of children's food acceptance which are reviewed include parental and peer modeling, the family food environment, infant feeding practices including breastfeeding and age at weaning, concurrent feeding practices including restriction, pressure to eat, prompting and reward, and the taste & energy content of foods. Children's willingness to accept new foods is influenced by a wide range of factors that likely have individual and also interactive effects on children's willingness to taste, and then continue to eat, new foods. The literature lacks longitudinal and experimental studies, which will be particularly important in determining interventions most likely to be effective in facilitating children's acceptance of healthy foods.

  10. A model for nonexercising hindlimb muscles in exercising animals.

    Science.gov (United States)

    Bonen, A; Blewett, C; McDermott, J C; Elder, G C

    1990-07-01

    Nonexercising muscles appear to be metabolically active during exercise. Animal models for this purpose have not been established. However, we have been able to teach animals to run on their forelimbs while their hindlimbs are suspended above the treadmill with no visible limb movement. To document that indeed this mode of exercise does not provoke additional muscle activity, we have compared the levels of neural activation of the soleus and plantaris muscles using a computer analysis of the electromyographic interference pattern, recorded from bipolar fine wire electrodes implanted across each muscle. Via computer analyses of the electromyographic interference patterns the frequencies and amplitudes of motor unit action potentials were obtained. The data were sampled during 20 s of every minute of observation. Comparisons were made in four conditions: (i) resting on the treadmill while bearing weight on the hindlimbs (normal rest), (ii) running on the treadmill (15 m/min, 8% grade) on all four limbs (normal exercise), (iii) resting while the hindlimbs were suspended in a harness above the treadmill (suspended rest), and (iv) exercising with the forelimbs (15 m/min, 8% grade) while the hindlimbs were suspended above the treadmill (suspended exercise). All four experimental conditions were carried out for 90 min each and were performed by each animal. The results clearly show that muscle activities (frequencies and amplitudes), when the hindlimbs are suspended above the treadmill, at rest or during exercise, are lower than the activities in these same muscles when the animals are at rest, supporting only their body weight. Activities in the same muscles during exercise were from 300 to 2000% greater than during hindlimb suspension.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Design of Driving Mechanism UUV Forelimb%扑翼UUV前肢驱动机构设计

    Institute of Scientific and Technical Information of China (English)

    梁庆卫; 杨璞; 曹永辉; 陈良军

    2012-01-01

    通过对海龟前肢运动特点的分析和研究,对扑翼进行受力分析,充分利用惯性与流体力的作用,基于Unigraphics 软件,实现前肢扑翼驱动机构的虚拟样机设计,简述此机构的周期运动过程,通过计算与仿真得出其粗略的推进力曲线及驱动电机参数,验证了机构的合理性.%By analyzing and studying the moving characteristic of turtle's forelimb,making full use of the role of inertia and fluid force, forelimb flapping actuator virtual prototype design the periodic motion process of this body, is sketched. The rough curve of pro-pulsion and the drive motor parameters are obtained and it is verify that the design is reasonable by calculation and simulation.

  12. Development of a universal measure of quadrupedal forelimb-hindlimb coordination using digital motion capture and computerised analysis

    Directory of Open Access Journals (Sweden)

    Jeffery Nick D

    2007-09-01

    Full Text Available Abstract Background Clinical spinal cord injury in domestic dogs provides a model population in which to test the efficacy of putative therapeutic interventions for human spinal cord injury. To achieve this potential a robust method of functional analysis is required so that statistical comparison of numerical data derived from treated and control animals can be achieved. Results In this study we describe the use of digital motion capture equipment combined with mathematical analysis to derive a simple quantitative parameter – 'the mean diagonal coupling interval' – to describe coordination between forelimb and hindlimb movement. In normal dogs this parameter is independent of size, conformation, speed of walking or gait pattern. We show here that mean diagonal coupling interval is highly sensitive to alterations in forelimb-hindlimb coordination in dogs that have suffered spinal cord injury, and can be accurately quantified, but is unaffected by orthopaedic perturbations of gait. Conclusion Mean diagonal coupling interval is an easily derived, highly robust measurement that provides an ideal method to compare the functional effect of therapeutic interventions after spinal cord injury in quadrupeds.

  13. Ossification Pattern of Estuarine Dolphin (Sotalia guianensis Forelimbs, from the Coast of the State of Espirito Santo, Brazil.

    Directory of Open Access Journals (Sweden)

    Anna Paula Martins de Carvalho

    Full Text Available The estuarine dolphin, Sotalia guianensis, is one of the most abundant cetacean species in Brazil. Determination of age and of aspects associated with the development of this species is significant new studies. Counts of growth layer groups in dentin are used to estimate age of these animals, though other ways to evaluate development are also adopted, like the measurement of total length (TL. This study presents a procedure to evaluate the development of the estuarine dolphin based on the ossification pattern of forelimbs. Thirty-seven estuarine dolphins found in the state of Espírito Santo, Brazil, were examined. Age was estimated, TL was measured and ossification of epiphyses was examined by radiography. We analyzed results using the Spearman correlation. Inspection of radiographs allowed evaluation of the significance of the correlation between age and development of the proximal (r = 0.9109 and distal (r = 0.9092 radial epiphyses, and of the distal ulnar epiphyses (r = 0.9055. Radiographic analysis of forelimbs proved to be an appropriate method to evaluate physical maturity, and may be a helpful tool to estimate age of these animals in ecological and population studies.

  14. Record-Breaking Pain: The Largest Number and Variety of Forelimb Bone Maladies in a Theropod Dinosaur.

    Directory of Open Access Journals (Sweden)

    Phil Senter

    Full Text Available Bone abnormalities are common in theropod dinosaur skeletons, but before now no specimen was known with more than four afflicted bones of the pectoral girdle and/or forelimb. Here we describe the pathology of a specimen of the theropod dinosaur Dilophosaurus wetherilli with eight afflicted bones of the pectoral girdle and forelimb. On its left side the animal has a fractured scapula and radius and large fibriscesses in the ulna and the proximal thumb phalanx. On its right side the animal has abnormal torsion of the humeral shaft, bony tumors on the radius, a truncated distal articular surface of metacarpal III, and angular deformities of the first phalanx of the third finger. Healing and remodeling indicates that the animal survived for months and possibly years after its ailments began, but its right third finger was permanently deformed and lacked the capability of flexion. The deformities of the humerus and the right third finger may be due to developmental osteodysplasia, a condition known in extant birds but unreported in non-avian dinosaurs before now.

  15. Record-Breaking Pain: The Largest Number and Variety of Forelimb Bone Maladies in a Theropod Dinosaur.

    Science.gov (United States)

    Senter, Phil; Juengst, Sara L

    2016-01-01

    Bone abnormalities are common in theropod dinosaur skeletons, but before now no specimen was known with more than four afflicted bones of the pectoral girdle and/or forelimb. Here we describe the pathology of a specimen of the theropod dinosaur Dilophosaurus wetherilli with eight afflicted bones of the pectoral girdle and forelimb. On its left side the animal has a fractured scapula and radius and large fibriscesses in the ulna and the proximal thumb phalanx. On its right side the animal has abnormal torsion of the humeral shaft, bony tumors on the radius, a truncated distal articular surface of metacarpal III, and angular deformities of the first phalanx of the third finger. Healing and remodeling indicates that the animal survived for months and possibly years after its ailments began, but its right third finger was permanently deformed and lacked the capability of flexion. The deformities of the humerus and the right third finger may be due to developmental osteodysplasia, a condition known in extant birds but unreported in non-avian dinosaurs before now.

  16. Intrinsic or Extrinsic? Using Videogames to Motivate Stroke Survivors: A Systematic Review.

    Science.gov (United States)

    Swanson, LaTasha R; Whittinghill, David M

    2015-06-01

    The main objective of this study was to explore, via a systematic review of available literature, the effectiveness of videogame-based rehabilitation interventions on the motivation and health outcomes of stroke patients. Using a systematic literature review of 18 articles, we sought to address three key research questions: (1) Do videogames improve function or health outcomes among stroke survivors? (2) Do videogames increase stroke patients' motivation to engage in rehabilitation exercise and activities? (3) Which motivational techniques, principles, and theoretical frameworks have been applied in the reviewed studies? A key word search was conducted, and articles were coded for inclusion of motivational theories or principles, intervention effectiveness, and participants' motivation to perform tasks. Three motivational frameworks and principles were used (self-determination theory [SDT], flow theory, and operant conditioning) to investigate intrinsic and extrinsic approaches. Past research suggests videogame-based interventions are effective at improving and increasing a variety of health-related outcomes, including motor functioning, energy expenditure, muscle strength, and recovery times in stroke patients. Past evidence shows videogame-based interventions are a promising tool to motivate stroke patients' engagement in effective rehabilitation activities. This study also identifies an opportunity for future research to apply motivational theories from SDT to studies on stroke rehabilitation and videogames.

  17. Skeletal muscle

    Science.gov (United States)

    There are approximately 650-850 muscles in the human body these include skeletal (striated), smooth and cardiac muscle. The approximation is based on what some anatomists consider separate muscle or muscle systems. Muscles are classified based on their anatomy (striated vs. smooth) and if they are v...

  18. Efficacy test of a toothpaste in reducing extrinsic dental stain

    Science.gov (United States)

    Agustanti, A.; Ramadhani, S. A.; Adiatman, M.; Rahardjo, A.; Callea, M.; Yavuz, I.; Maharani, D. A.

    2017-08-01

    This clinical trial compared the external dental stain reduction achieved by tested toothpaste versus placebo in adult patients. In this double-blind, parallel, randomised clinical trial, 45 female volunteers with a mean age of 20 years old were included. All study subjects front teeth were topically applicated with Silver Diamine Fluoride (SDF) to create external dental stains. Subjects were randomized into test (n=22) and control (n=23) groups. Toothpastes were used for two days to analyse the effects of removing external stains on the labial surfaces of all anterior teeth. VITA Easyshade Advance 4.0 was used to measure dental extrinsic stains changes. The analysis showed statistically significant efficacy of the tested toothpaste in reducing external dental stain caused by SDF, comparing to the placebo toothpaste, after one and two days of usage. The tested toothpaste was effective in reducing dental stain.

  19. Extrinsic factors affecting accuracy of ultrasonic flowmeters for LMFBRs

    Energy Technology Data Exchange (ETDEWEB)

    Managan, W.W.

    1976-08-01

    Assuming that ultrasonic flowmeters of suitable intrinsic accuracy are feasible, this report explores factors extrinsic to the flowmeter which affect the accuracy such as asymmetric flow profile, regions of high turbulence and thermal stratification. By integrating isovelocity flow profile maps, the predicted performance of various flowmeter configurations may be compared to experimental data. For the two pipe arrangements analyzed, the single diametral path flowmeter results were within 5 percent of true flow rate. Theoretical correction factors could reduce the error for the straight pipe but increased the error for asymmetrical flow. On the same pipe arrangements a four path ultrasonic flowmeter spaced for Gaussian integration gave less than 1 percent error. For more general conclusions a range of flow profiles produced by typical LMFBR piping arrangements must be analyzed.

  20. Extrinsic allergic alveolitis induced by the yeast Debaryomyces hansenii.

    Science.gov (United States)

    Yamamoto, Y; Osanai, S; Fujiuchi, S; Yamazaki, K; Nakano, H; Ohsaki, Y; Kikuchi, K

    2002-11-01

    A 65-yr-old female developed cough, fever and dyspnoea following repeated exposure to a home ultrasonic humidifier. High-resolution computed tomography showed ground-glass opacity in both lung fields. Arterial blood gas analysis gave an oxygen tension of 8.38 kPa (63 Torr). Pulmonary function testing revealed restrictive ventilatory impairment with a reduction in the diffusing capacity. The diagnosis of extrinsic allergic alveolitis (EAA) was confirmed by radiographic findings, pathological evidence of alveolitis and reproductive development by a provocation test to the humidifier water. The yeast Debaryomyces Hansenii was the only microorganism cultured from the water of the humidifier. The double diffusion precipitating test and lymphocyte proliferative response was positive for an extract of D. Hansenii, providing evidence to incriminate this fungus. This is the first described case of EAA caused by D. Hansenii.

  1. MATERIAL ELEMENT MODEL FOR EXTRINSIC SEMICONDUCTORS WITH DEFECTS OF DISLOCATION

    Directory of Open Access Journals (Sweden)

    Maria Paola Mazzeo

    2011-07-01

    Full Text Available In a previous paper we outlined a geometric model for the thermodynamic description of extrinsic semiconductors with defects of dislocation.Applying a geometrization technique, within the rationalextended irreversible thermodynamics with internal variables, the dynamical system for simple material elements of these media, the expressions of the entropy function and the entropy 1-form were obtained. In this contribution we deepen the study of this geometric model. We give a detailed description of the defective media under consideration and of the dislocation core tensor, we introduce the transformation induced by the process and, applying the closure conditions for the entropy 1-form, we derive the necessary conditions for the existence of the entropy function. These and other results are new in the paper.The derivation of the relevant entropy 1-form is the starting point to introduce an extended thermodynamical phase space.

  2. Measurement of Spin Pumping Voltage Separated from Extrinsic Microwave Effects

    Science.gov (United States)

    Iguchi, Ryo; Saitoh, Eiji

    2017-01-01

    Conversions between spin and charge currents are core technologies in recent spintronics. In this article, we provide methods for estimating inverse spin Hall effects (ISHEs) induced by using microwave-driven spin pumping (SP) as a spin-current generator. ISHE and SP induce an electromotive force at the ferromagnetic or spin-wave resonance, which offers a valuable electric method of studying spin physics in materials. At the resonance, a microwave for exciting the magnetization dynamics induces an additional electromotive force via rf-current rectification and thermoelectric effects. We discuss methods of separating the signals generated from such extrinsic microwave effects by controlling sample structures and configurations. These methods are helpful in performing accurate measurements on ISHE induced by SP, enabling quantitative studies on the conversion between spin and charge currents on various kinds of materials.

  3. Alberta Consumers' Valuation of Extrinsic and Intrinsic Red Meat Attributes

    DEFF Research Database (Denmark)

    Steiner, Bodo; Gao, Fei; Unterschultz, Jim

    2010-01-01

    This paper analyzes Alberta consumers’ perceptions toward extrinsic and intrinsic attributes of bison and beef steaks. In contrast to published Canadian consumer studies on bison meat that were undertaken prior to May 2003, before the first BSE case of Canadian origin was identified in beef cattle......, this study provides a “post-BSE” assessment of consumer perceptions toward selected bison meat attributes. The results from an attribute-based choice experiment provide little support that simple traceability assurance schemes have value to consumers of bison and beef steaks, thus confirming similar findings...... of earlier beef studies that have employed different methodological approaches. The results also suggest that consumers are willing to pay significant premiums for bison steaks that are certified as being produced without genetically modified organisms, an attribute that has so far been unexplored...

  4. Extrinsic and intrinsic motivation at 30: Unresolved scientific issues.

    Science.gov (United States)

    Reiss, Steven

    2005-01-01

    The undermining effect of extrinsic reward on intrinsic motivation remains unproven. The key unresolved issues are construct invalidity (all four definitions are unproved and two are illogical); measurement unreliability (the free-choice measure requires unreliable, subjective judgments to infer intrinsic motivation); inadequate experimental controls (negative affect and novelty, not cognitive evaluation, may explain "undermining" effects); and biased metareviews (studies with possible floor effects excluded, but those with possible ceiling effects included). Perhaps the greatest error with the undermining theory, however, is that it does not adequately recognize the multifaceted nature of intrinsic motivation (Reiss, 2004a). Advice to limit the use of applied behavior analysis based on "hidden" undermining effects is ideologically inspired and is unsupported by credible scientific evidence.

  5. Smooth muscle cell–extrinsic vascular spasm arises from cardiomyocyte degeneration in sarcoglycan-deficient cardiomyopathy

    OpenAIRE

    Wheeler, Matthew T.; Allikian, Michael J.; Heydemann, Ahlke; Hadhazy, Michele; Zarnegar, Sara; McNally, Elizabeth M.

    2004-01-01

    Vascular spasm is a poorly understood but critical biomedical process because it can acutely reduce blood supply and tissue oxygenation. Cardiomyopathy in mice lacking γ-sarcoglycan or δ-sarcoglycan is characterized by focal damage. In the heart, sarcoglycan gene mutations produce regional defects in membrane permeability and focal degeneration, and it was hypothesized that vascular spasm was responsible for this focal necrosis. Supporting this notion, vascular spasm was noted in coronary art...

  6. The Technologies of Normalization and Self: Thinking about IRBs and Extrinsic Research Ethics with Foucault

    Science.gov (United States)

    Koro-Ljungberg, Mirka; Gemignani, Marco; Brodeur, Cheri Winton; Kmiec, Cheryl

    2007-01-01

    In this article, the authors discuss the technologies of normalization and self in relation to ethics and the problematization of extrinsic research ethics. They argue that institutional review boards (IRBs) and other similar institutional mechanisms promote extrinsic forms of ethics that are exemplified through institutionalized structures such…

  7. Intrinsic and Extrinsic School Motivation as a Function of Age: The Mediating Role of Autonomy Support

    Science.gov (United States)

    Gillet, Nicolas; Vallerand, Robert J.; Lafreniere, Marc-Andre K.

    2012-01-01

    The main purpose of the present research was to investigate school intrinsic and extrinsic motivation, and amotivation as a function of age in a sample of 1,600 elementary and high school students aged 9-17 years. First, results revealed a systematic decrease in intrinsic motivation and self-determined extrinsic motivation from age 9 to 12 years,…

  8. Creating Rich Portraits: A Mixed-Methods Approach to Understanding Profiles of Intrinsic and Extrinsic Motivations

    Science.gov (United States)

    Corpus, Jennifer Henderlong; Wormington, Stephanie V.; Haimovitz, Kyla

    2016-01-01

    A person-centered, mixed-methods approach (self-report surveys, semistructured interviews, school records) was used to characterize and evaluate profiles of intrinsic and extrinsic motivations among 243 third- through eighth-grade students. Cluster analysis suggested four distinct profiles: high quantity (high intrinsic, high extrinsic), primarily…

  9. Intrinsic and Extrinsic School Motivation as a Function of Age: The Mediating Role of Autonomy Support

    Science.gov (United States)

    Gillet, Nicolas; Vallerand, Robert J.; Lafreniere, Marc-Andre K.

    2012-01-01

    The main purpose of the present research was to investigate school intrinsic and extrinsic motivation, and amotivation as a function of age in a sample of 1,600 elementary and high school students aged 9-17 years. First, results revealed a systematic decrease in intrinsic motivation and self-determined extrinsic motivation from age 9 to 12 years,…

  10. Intrinsic and Extrinsic Origins of the Polar Kerr Effect in a Chiral p-WAVE Superconductor

    Science.gov (United States)

    Goryo, Jun

    Recently, the measurement of the polar Kerr effect (PKE) in the quasi two-dimensional superconductor Sr2RuO4, which is motivated to observe the chirality of px + ipy-wave pairing, has been reported. We clarify that the PKE has intrinsic and extrinsic (disorder-induced) origins. The extrinsic contribution would be dominant in the PKE experiment.

  11. Do people differentiate between intrinsic and extrinsic goals for physical activity?

    Science.gov (United States)

    McLachlan, Sarah; Hagger, Martin S

    2011-04-01

    The distinction between intrinsic and extrinsic goals, and between goal pursuit for intrinsically and extrinsically motivated reasons, is a central premise of self-determination theory. Proponents of the theory have proposed that the pursuit of intrinsic goals and intrinsically motivated goal striving each predict adaptive psychological and behavioral outcomes relative to the pursuit of extrinsic goals and extrinsically motivated goal striving. Despite evidence to support these predictions, research has not explored whether individuals naturally differentiate between intrinsic and extrinsic goals. Two studies tested whether people make this differentiation when recalling goals for leisure-time physical activity. Using memory-recall methods, participants in Study 1 were asked to freely generate physical activity goals. A subsample (N = 43) was asked to code their freely generated goals as intrinsic or extrinsic. In Study 2, participants were asked to recall intrinsic and extrinsic goals after making a decision regarding their future physical activity. Results of these studies revealed that individuals' goal generation and recall exhibited significant clustering by goal type. Participants encountered some difficulties when explicitly coding goals. Findings support self-determination theory and indicate that individuals discriminate between intrinsic and extrinsic goals.

  12. Creating Rich Portraits: A Mixed-Methods Approach to Understanding Profiles of Intrinsic and Extrinsic Motivations

    Science.gov (United States)

    Corpus, Jennifer Henderlong; Wormington, Stephanie V.; Haimovitz, Kyla

    2016-01-01

    A person-centered, mixed-methods approach (self-report surveys, semistructured interviews, school records) was used to characterize and evaluate profiles of intrinsic and extrinsic motivations among 243 third- through eighth-grade students. Cluster analysis suggested four distinct profiles: high quantity (high intrinsic, high extrinsic), primarily…

  13. Proprioceptive bimanual test in intrinsic and extrinsic coordinates.

    Science.gov (United States)

    Iandolo, Riccardo; Squeri, Valentina; De Santis, Dalia; Giannoni, Psiche; Morasso, Pietro; Casadio, Maura

    2015-01-01

    Is there any difference between matching the position of the hands by asking the subjects to move them to the same spatial location or to mirror-symmetric locations with respect to the body midline? If the motion of the hands were planned in the extrinsic space, the mirror-symmetric task would imply an additional challenge, because we would need to flip the coordinates of the target on the other side of the workspace. Conversely, if the planning were done in intrinsic coordinates, in order to move both hands to the same spot in the workspace, we should compute different joint angles for each arm. Even if both representations were available to the subjects, the two tasks might lead to different results, providing some cue on the organization of the "body schema". In order to answer such questions, the middle fingertip of the non-dominant hand of a population of healthy subjects was passively moved by a manipulandum to 20 different target locations. Subjects matched these positions with the middle fingertip of their dominant hand. For most subjects, the matching accuracy was higher in the extrinsic modality both in terms of systematic error and variability, even for the target locations in which the configuration of the arms was the same for both modalities. This suggests that the matching performance of the subjects could be determined not only by proprioceptive information but also by the cognitive representation of the task: expressing the goal as reaching for the physical location of the hand in space is apparently more effective than requiring to match the proprioceptive representation of joint angles.

  14. Effect of varying the intensity and train frequency of forelimb and cerebellar mossy fiber conditioned stimuli on the latency of conditioned eye-blink responses in decerebrate ferrets.

    Science.gov (United States)

    Svensson, P; Ivarsson, M; Hesslow, G

    1997-01-01

    To study the role of the mossy fiber afferents to the cerebellum in classical eye-blink conditioning, in particular the timing of the conditioned responses, we compared the effects of varying a peripheral conditioned stimulus with the effects of corresponding variations of direct stimulation of the mossy fibers. In one set of experiments, decerebrate ferrets were trained in a Pavlovian eye-blink conditioning paradigm with electrical forelimb train stimulation as conditioned stimulus and electrical periorbital stimulation as the unconditioned stimulus. When stable conditioning had been achieved, the effect of increasing the intensity or frequency of the forelimb stimulation was tested. By increasing the intensity from 1 to 2 mA, or the train frequency from 50 to 100 Hz, an immediate decrease was induced in both the onset latency and the latency to peak of the conditioned response. If the conditioned stimulus intensity/frequency was maintained at the higher level, the response latencies gradually returned to preshift values. In a second set of experiments, the forelimb stimulation was replaced by direct train stimulation of the middle cerebellar peduncle as conditioned stimulus. Varying the frequency of the stimulus train between 50 and 100 Hz had effects that were almost identical to those obtained when using a forelimb conditioned stimulus. The functional meaning of the latency effect is discussed. It is also suggested that the results support the view that the conditioned stimulus is transmitted through the mossy fibers and that the mechanism for timing the conditioned response is situated in the cerebellum.

  15. Muscle Deoxygenation Causes Muscle Fatigue

    Science.gov (United States)

    Murthy, G.; Hargens, A. R.; Lehman, S.; Rempel, D.

    1999-01-01

    Muscle fatigue is a common musculoskeletal disorder in the work place, and may be a harbinger for more disabling cumulative trauma disorders. Although the cause of fatigue is multifactorial, reduced blood flow and muscle oxygenation may be the primary factor in causing muscle fatigue during low intensity muscle exertion. Muscle fatigue is defined as a reduction in muscle force production, and also occurs among astronauts who are subjected to postural constraints while performing lengthy, repetitive tasks. The objectives of this research are to: 1) develop an objective tool to study the role of decreased muscle oxygenation on muscle force production, and 2) to evaluate muscle fatigue during prolonged glovebox work.

  16. Influence of exercise contraction mode and protein supplementation on human skeletal muscle satellite cell content and muscle fiber growth.

    Science.gov (United States)

    Farup, Jean; Rahbek, Stine Klejs; Riis, Simon; Vendelbo, Mikkel Holm; Paoli, Frank de; Vissing, Kristian

    2014-10-15

    Skeletal muscle satellite cells (SCs) are involved in remodeling and hypertrophy processes of skeletal muscle. However, little knowledge exists on extrinsic factors that influence the content of SCs in skeletal muscle. In a comparative human study, we investigated the muscle fiber type-specific association between emergence of satellite cells (SCs), muscle growth, and remodeling in response to 12 wk unilateral resistance training performed as eccentric (Ecc) or concentric (Conc) resistance training ± whey protein (Whey, 19.5 g protein + 19.5 g glucose) or placebo (Placebo, 39 g glucose) supplementation. Muscle biopsies (vastus lateralis) were analyzed for fiber type-specific SCs, myonuclei, and fiber cross-sectional area (CSA). Following training, SCs increased with Conc in both type I and type II fibers (P hypertrophy correlated with whole muscle hypertrophy exclusively following Conc training (P eccentric resistance training while type II fiber hypertrophy was accentuated when combining concentric resistance training with whey protein supplementation.

  17. Muscle disorder

    Science.gov (United States)

    Myopathic changes; Myopathy; Muscle problem ... Blood tests sometimes show abnormally high muscle enzymes. If a muscle disorder might also affect other family members, genetic testing may be done. When someone has symptoms and signs ...

  18. Motor ability of forelimb both on- and off-riding during walk and trot cadence of horse

    Science.gov (United States)

    Hyun, Seung-Hyun; Ryew, Che-Cheong

    2016-01-01

    The aim of this study was to investigate the motor ability of forelimb according to on- or off-riding during cadences (walk and trot) of horse. Horses and rider selected as subject consisted of total 37 heads of Jeju native horse and 1 female rider. The variables analyzed composed of 1 stride length, 1 step length, elapsed time of stance, elapsed time of swing, elapsed time of 1 step, and forward velocity (x-axis). Two-way analysis of variance of variables was employed for the statistical analysis with the level of significance set at 5% (Phorse’s analysis meant that there was very close relation among variables of rider’s weight-velocity-stride length-stride elapsed time. Next study will be necessary to analyze cadence variables added both stride length and rider’s weight for riding activity and rehabilitation during horse riding using Jeju native horse. PMID:26933662

  19. Functional morphology and biomechanics of the cynodont Trucidocynodon riograndensis from the Triassic of Southern Brazil: Pectoral girdle and forelimb

    Directory of Open Access Journals (Sweden)

    Téo Veiga De Oliveira

    2016-06-01

    Full Text Available Non-mammalian cynodonts provide insights on several points about mammalian evolution, such as the postural change and locomotory advances within the group. Unfortunately, complete skeletons of Triassic cynodonts are rather uncommon and where more complete specimens are found they can offer a global vision on some traits not available from partial specimens. This is the case of the cynodont Trucidocynodon riograndensis, from the Triassic of Brazil, that has preserved its forelimbs providing some insights into locomotory properties. The movements between interclavicle and clavicle must have been limited, as such as those occurring between the latter and the scapulocoracoid although the long acromion process of this should have permitted a greater degree of freedom. Some of the more significant movements were those on the shoulder joint, in which the maximum adduction should have been ca. 35º relative to the parasagittal plane and the greater abduction ca. 55º. The maximum adduction occurred when the humerus was in the more retracted position during stride and the variation in the adduction/abduction should have been significant to the limb posture during its recovery stroke. The long olecranon and the distal overlapping between radius and ulna suggest the predominance of simple flexion/extension on the forearm without significant pronation/supination. The poorly preserved hand suggests that Trucidocynodon could have evolved a slight semidigitigrad condition in its forelimbs. All these features give to this cynodont an important role in the evolution of the mammalian locomotory properties indicating that some features, such as the possibility of greater humeral adduction, evolved early in cynodont lineage.

  20. Tissue growth patterns in the carcasses of water buffalo and Friesian crossbred cattle-part 1: Individual muscles and anatomical muscle groups.

    Science.gov (United States)

    Abdallah, O Y

    1983-01-01

    The left sides of the carcasses of twelve Egyptian buffalo, nine half Friesian (♂ Friesian x ♀ Egyptian Baladi) and nine three-quarter Friesian (♂ x ♀ half-Friesian) bulls, serially slaughtered between 161 and 560 kg for buffaloes and between 176 and 448 kg for cattle, were used to describe the growth and distribution of individual muscles and muscle groups. Genotype-group differences in the relative rate of growth were not significant in 85 of 89 muscles and in 8 of 9 muscle groups. The pooled within-group growth coefficients of individual muscles revealed different increasing growth gradients, i.e. disto-proximal in both limbs, mediolateral in the proximal pelvic limb, from elbow flexors to shoulder flexors in the proximal thoracic limb, caudo-cranial in the trunk and from hypaxial to epaxial muscles around the spinal column. The relative growth was lowest in the distal part of the limbs and highest in the anterior part of the carcass (SMG 7 and 8), with the loin and abdominal muscle groups growing at a rate similar to that of the total muscle. The neck and thorax muscle group grew at a higher rate in Friesian crosses than in buffaloes. Genotype-group differences in the weight of each muscle relative to total side muscle (TSM) were significant in 50 of 89 muscles. Of the 50 muscles (constituting around 59% of TSM), 24 (approximately 44% of TSM) were from the expensive muscle groups. As compared with the most different Friesian cross (base = 100) at equal TSM, buffaloes had higher weight of muscle in the hindlimb (107·5% proximally; 106·3% distally) and forelimb (120·0% proximally: 104·6% distally) and significantly less weight of the muscle groups forming the abdominal wall (79·8%) and connecting the forelimb to the thorax (89·1%) and to the neck (90·7%). The weight of the combined expensive groups was significantly greater in buffaloes than in cattle (maximum difference = 1·8 kg) with a tendency for buffaloes to have relatively less of the tender

  1. The interosseous muscles: the foundation of hand function.

    Science.gov (United States)

    Liss, Frederic E

    2012-02-01

    The interosseous muscles of the hand can be thought of as the cornerstone of hand function, as they provide a "foundation" for all intrinsic and extrinsic hand movements. Innervated by the ulnar nerve and organized in dorsal and palmar layers, these pivotal muscles have small excursion yet great impact on finger balance, grip, and pinch function, particularly when impaired by denervation and/or contracture. This article gives an overview of the functional anatomy and pathologic dysfunction of the interosseous muscles within the context of this Hand Clinics issue on the intrinsic muscular function of the hand. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Distinguishing subtypes of extrinsic motivation among people with mild to borderline intellectual disability.

    Science.gov (United States)

    Frielink, N; Schuengel, C; Embregts, P

    2017-07-01

    According to self-determination theory, motivation is ordered in types, including amotivation, extrinsic motivation and intrinsic motivation. Self-determination theory defines four subtypes of extrinsic motivation: external motivation, introjected motivation, identified motivation and integrated motivation. Although it has been argued theoretically that the different types of motivation are universally applicable, Reid et al. () proposed a dichotomy of broad subtypes of extrinsic motivation for people with intellectual disability (ID) due to their cognitive limitations. The current study challenges this proposal by testing whether the four subtypes of extrinsic motivation can be differentiated among people with ID as well. The subtypes of extrinsic motivation were measured using two adapted versions of the Self-Regulation Questionnaire, one regarding exercise and one regarding support. In total, 186 adults with mild to borderline ID participated in the study. Results supported the distinction between the four subtypes of extrinsic motivation regarding both exercise and support. In addition, the correlation coefficients supported a quasi-simplex pattern of correlations among the subtypes, indicating that adjacent subtypes were more closely related than non-adjacent subtypes. Moreover, the study showed sufficient Cronbach's alphas and test-retest reliabilities for early stage research. Overall, the results of the current study provide initial evidence for the universality of the four subtypes of extrinsic motivation across populations with and without ID. © 2017 The Authors. Journal of Intellectual Disability Research published by MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disibilities and John Wiley & Sons Ltd.

  3. Intrinsic and Extrinsic Motivation Among Adolescent Ten-Pin Bowlers in Kuala Lumpur, Malaysia

    Directory of Open Access Journals (Sweden)

    Teo Eng-Wah

    2015-03-01

    Full Text Available Motivation has long been associated with sports engagement. However, to date no research has been performed to understand the domain of motivation among ten-pin bowlers. The purpose of this study was to investigate different types of motivation (i.e., intrinsic vs. extrinsic based on self-determination theory from the perspective of gender and the bowler type (competitive vs. casual. A total of 240 bowlers (104 male, 136 female; 152 competitive, 88 casual with a mean age of 16.61 ± 0.78 years were recruited in Kuala Lumpur. The Sport Motivation Scale, a 28-item self-report questionnaire measuring seven subscales (i.e., intrinsic motivation to know, intrinsic motivation to accomplish, intrinsic motivation to experience stimulation, extrinsic motivation to identify regulation, extrinsic motivation for introjection regulation, extrinsic motivation to external regulation, and amotivation was administered. Results showed significant differences (t=10.43, df=239, p=0.01 between total scores of intrinsic and extrinsic motivation among tenpin bowlers. There were significant gender differences with respect to intrinsic motivation to know, intrinsic motivation to accomplish, intrinsic motivation to experience stimulation, and extrinsic motivation to identify regulation. However, no significant bowler type differences were found for either the intrinsic (t=-1.15, df=238, p=0.25 or extrinsic (t=-0.51, df=238, p=0.61 motivation dimensions. In conclusion, our study demonstrated substantial intrinsic motivation for gender effects, but no bowler type effects among adolescent ten-pin bowlers.

  4. Intrinsic and extrinsic motivation among adolescent ten-pin bowlers in kuala lumpur, malaysia.

    Science.gov (United States)

    Teo, Eng-Wah; Khoo, Selina; Wong, Rebecca; Wee, Eng-Hoe; Lim, Boon-Hooi; Rengasamy, Shabesan Sit

    2015-03-29

    Motivation has long been associated with sports engagement. However, to date no research has been performed to understand the domain of motivation among ten-pin bowlers. The purpose of this study was to investigate different types of motivation (i.e., intrinsic vs. extrinsic) based on self-determination theory from the perspective of gender and the bowler type (competitive vs. casual). A total of 240 bowlers (104 male, 136 female; 152 competitive, 88 casual) with a mean age of 16.61 ± 0.78 years were recruited in Kuala Lumpur. The Sport Motivation Scale, a 28-item self-report questionnaire measuring seven subscales (i.e., intrinsic motivation to know, intrinsic motivation to accomplish, intrinsic motivation to experience stimulation, extrinsic motivation to identify regulation, extrinsic motivation for introjection regulation, extrinsic motivation to external regulation, and amotivation) was administered. Results showed significant differences (t=10.43, df=239, p=0.01) between total scores of intrinsic and extrinsic motivation among ten-pin bowlers. There were significant gender differences with respect to intrinsic motivation to know, intrinsic motivation to accomplish, intrinsic motivation to experience stimulation, and extrinsic motivation to identify regulation. However, no significant bowler type differences were found for either the intrinsic (t=-1.15, df=238, p=0.25) or extrinsic (t=-0.51, df=238, p=0.61) motivation dimensions. In conclusion, our study demonstrated substantial intrinsic motivation for gender effects, but no bowler type effects among adolescent ten-pin bowlers.

  5. Bridging the gap between extrinsic and intrinsic motivation in the cognitive remediation of schizophrenia.

    Science.gov (United States)

    Silverstein, Steven M

    2010-09-01

    An important development in cognitive remediation of schizophrenia is a focus on motivation. However, following a distinction between the concepts of intrinsic motivation (IM) and extrinsic motivation, discussions of IM-based methods have downplayed or misrepresented the role that extrinsic rewards can, and actually do, serve to promote positive treatment outcomes in cognitive remediation. Therefore, the purpose of this article is to explore the rationale for using techniques incorporating extrinsic rewards into cognitive treatment of people with schizophrenia. To do this, evidence is presented on each of the following points: (1) there is a long history of research demonstrating that delivery of extrinsic reward is associated with positive outcomes in both behavioral and cognitive rehabilitation; (2) basic human brain systems respond strongly to tangible rewards, and this can directly enhance attention, working memory, and other cognitive functions; (3) nearly all data on the negative effects of extrinsic reward on IM have come from studies of healthy children and adults in school or work settings who have adequate IM for target tasks; these findings do not generalize well to cognitive remediation settings for people with schizophrenia, who often have abnormally low levels of IM and low base rates of attentive behaviors; and (4) in real-world situations, cognitive remediation interventions already utilize a combination of intrinsic and extrinsic reinforcers. Future studies are needed to clarify state and trait factors responsible for individual differences in the extent to which extrinsic rewards are necessary to set the conditions under which IM can develop.

  6. Across-muscle coherence is modulated as a function of wrist posture during two-digit grasping.

    Science.gov (United States)

    Jesunathadas, Mark; Laitano, Juan; Hamm, Thomas M; Santello, Marco

    2013-10-11

    The purpose of this study was to investigate the extent to which correlated neural inputs, quantified as EMG-EMG coherence across intrinsic and extrinsic hand muscles, varied as a function of wrist angle during a constant force precision grip task. Eight adults (5 males; mean age 29 years) participated in the experiment. Subjects held an object using a two-digit precision grip at a constant force at a flexed, neutral, and extended wrist posture, while the EMG activity from intrinsic and extrinsic hand muscles was recorded through intramuscular fine-wire electrodes. The integral of z-transformed coherence computed across muscles pairs was greatest in the flexed wrist posture and significantly greater than EMG-EMG coherence measured in the neutral and extended wrist posture (P < 0.01 and 0.05, respectively). Furthermore, EMG-EMG coherence did not differ statistically between the extrinsic and intrinsic muscle pairs, even though it tended to be greater for the extrinsic muscle pair (P ≥ 0.063). These findings lend support to the notion of a functional role of correlated neural inputs to hand muscles for the task-dependent coordination of hand muscle activity that is likely mediated by somatosensory feedback.

  7. Timing of Cortico-Muscle Transmission During Active Movement.

    Science.gov (United States)

    Van Acker, Gustaf M; Luchies, Carl W; Cheney, Paul D

    2016-08-01

    Numerous studies have reported large disparities between short cortico-muscle conduction latencies and long recorded delays between cortical firing and evoked muscle activity. Using methods such as spike- and stimulus-triggered averaging of electromyographic (EMG) activity, previous studies have shown that the time delay between corticomotoneuronal (CM) cell firing and onset of facilitation of forelimb muscle activity ranges from 6.7 to 9.8 ms, depending on the muscle group tested. In contrast, numerous studies have reported delays of 60-122 ms between cortical cell firing onset and either EMG or movement onset during motor tasks. To further investigate this disparity, we simulated rapid active movement by applying frequency-modulated stimulus trains to M1 cortical sites in a rhesus macaque performing a movement task. This yielded corresponding EMG modulations, the latency of which could be measured relative to the stimulus modulations. The overall mean delay from stimulus frequency modulation to EMG modulation was 11.5 ± 5.6 ms, matching closely the conduction time through the cortico-muscle pathway (12.6 ± 2.0 ms) derived from poststimulus facilitation peaks computed at the same sites. We conclude that, during active movement, the delay between modulated M1 cortical output and its impact on muscle activity approaches the physical cortico-muscle conduction time.

  8. Intrinsic and extrinsic motivations for healthful dietary change in African Americans.

    Science.gov (United States)

    Satia, Jessie A; Galanko, Joseph A

    2007-01-01

    To describe associations of intrinsic and extrinsic motivations for dietary change with participant characteristics and current diet among African Americans. Cross-sectional survey of 658 African American adults in North Carolina provided information on intrinsic (self-image and health concerns) and extrinsic (social influence) motivation scales, participant characteristics, and diet. Most respondents considered it important to change their diet for health reasons; fewer were motivated by self-image or social influence. Motivation scales were significantly associated with demographic, behavioral, and psychosocial characteristics and fat, but not fruit/vegetable consumption, after adjustment for covariates (Pintrinsic and extrinsic motives may improve the effectiveness of dietary interventions in African Americans.

  9. Intrinsic and extrinsic motivational orientations in the competitive context: an examination of person-situation interactions.

    Science.gov (United States)

    Abuhamdeh, Sami; Csikszentmihalyi, Mihaly

    2009-10-01

    The current study examined Intrinsic Motivation Orientation and Extrinsic Motivation Orientation (Work Preference Inventory; Amabile, Hill, Hennessey, & Tighe, 1994) as potential trait-level moderators of the way Internet chess players responded to the intrinsic and extrinsic rewards of the chess games they played. On the basis of the defining characteristics of these 2 types of motivational orientations, we predicted that (a) Intrinsic Motivation Orientation would be associated with a stronger curvilinear relationship between challenge and enjoyment and (b) Extrinsic Motivation Orientation would be associated with a heightened affective responsivity to competitive outcome (i.e., winning vs. losing). Results supported the predictions. Implications of the findings are discussed.

  10. Measurements of extrinsic fluorescence in Intralipid and polystyrene microspheres

    Science.gov (United States)

    Du Le, Vinh Nguyen; Nie, Zhaojun; Hayward, Joseph E.; Farrell, Thomas J.; Fang, Qiyin

    2014-01-01

    The fluorescence of Intralipid and polystyrene microspheres with sphere diameter of 1 µm at a representative lipid and microsphere concentration for simulation of mucosal tissue scattering has not been a subject of extensive experimental study. In order to elucidate the quantitative relationship between lipid and microsphere concentration and the respective fluorescent intensity, the extrinsic fluorescence spectra between 360 nm and 650 nm (step size of 5 nm) were measured at different lipid concentrations (from 0.25% to 5%) and different microsphere concentrations (0.00364, 0.0073, 0.0131 spheres per cubic micrometer) using laser excitation at 355 nm with pulse energy of 2.8 µJ. Current findings indicated that Intralipid has a broadband emission between 360 and 650 nm with a primary peak at 500 nm and a secondary peak at 450 nm while polystyrene microspheres have a single peak at 500 nm. In addition, for similar scattering properties the fluorescence of Intralipid solutions is approximately three-fold stronger than that of the microsphere solutions. Furthermore, Intralipid phantoms with lipid concentrations ~2% (simulating the bottom layer of mucosa) produce up to seven times stronger fluorescent emission than phantoms with lipid concentration ~0.25% (simulating the top layer of mucosa). The fluoresence decays of Intralipid and microsphere solutions were also recorded for estimation of fluorescence lifetime. PMID:25136497

  11. [Pathologic diagnosis and clinical analysis of chronic extrinsic allergic alveolitis].

    Science.gov (United States)

    Diao, Xiao-li; Jin, Mu-lan; Dai, Hua-ping; Li, Xue; Wei, Ping; Zhang, Yun-gang

    2011-11-01

    To study the clinicopathologic features and diagnostic approach of chronic extrinsic allergic alveolitis (EAA). Seven cases of chronic EAA diagnosed by open lung biopsy or lung transplant were enrolled into the study. The clinical and pathologic features were analyzed and the literature was reviewed. There were altogether 4 men and 3 women. The age of the patients ranged from 30 to 65 years (mean = 48 years). All cases represented chronic form and five cases diagnosed by open lung biopsy also showed features of recent aggravation, leading to hospitalization. Four cases had known history of exposure to inciting gases, pollens and pets, and only 2 cases were positive for allergens. High-resolution CT scan showed ground-glass attenuation and reticular pattern that often had a patchy distribution and central predominance. Bronchoalveolar lavage analysis showed marked lymphocytosis, with CD4(+)/CD8(+) ratio less than 1. Lung function test demonstrated a restrictive ventilatory defect, with decreased compliance, reduced diffusion capacity and high airway obstruction. Five cases had open lung biopsy performed and two cases had undergone lung transplantation. Pathologic examination showed bronchiolocentric cellular interstitial pneumonia, interstitial fibrosis, non-caseating epithelioid granulomas, epithelioid histiocytic infiltrate in the respiratory bronchioles and intraluminal budding fibrosis. The five cases with open lung biopsy performed also showed neutrophilic infiltrate in the alveoli. The two lung transplant cases were complicated by severe fibrotic changes. Chronic EAA demonstrates characteristic pathologic features. Definitive diagnosis requires correlation with clinical and radiologic findings due to possible morphologic mimicry of other diffuse parenchymal lung diseases.

  12. An outbreak of extrinsic alveolitis at a car engine plant.

    Science.gov (United States)

    Dawkins, Paul; Robertson, Alastair; Robertson, Wendy; Moore, Vicky; Reynolds, John; Langman, Gerald; Robinson, Edward; Harris-Roberts, Joanne; Crook, Brian; Burge, Sherwood

    2006-12-01

    Twelve workers from a car engine-manufacturing plant presented with extrinsic allergic alveolitis (EAA), with heterogeneous clinical, radiological and pathological findings. They were exposed to metalworking fluids (MWF) that cooled, lubricated and cleaned the machines. They were characterized by history, examination, lung function testing, radiology, bronchoscopic lavage, lung biopsy and serology. Sera were tested for precipitins to a crude extract of used MWF and to reference cultures of bacteria suspected to be implicated. All were males and none were current smokers. All had dyspnoea, many had weight loss and cough, but only half had influenza-like symptoms. Only half had auscultatory crackles. Five had peak flow variability, four with an occupational component. There was overall restrictive spirometry, decreased lung volumes and reduced gas transfers. Ten had radiological evidence of interstitial lung disease. Seven (of eight) had lymphocytosis on bronchial lavage, including the two with inconclusive radiology. Seven (of 11) had lung biopsies showing inflammatory infiltrates, two with fibrosis and one with granulomas. Three (of 11) had strong positive precipitins to an extract of the used MWF from the plant. Molecular biological analysis of the MWF revealed Acinetobacter and Ochrobactrum. Precipitins to Acinetobacter were detected in seven of 11 workers tested (and four of 11 control workers). Precipitins to Ochrobactrum were detected in three of 11 workers tested (and three of 11 control workers). This is the largest series reported in Europe of EAA due to an aerosol of microbiologically contaminated MWF in heavy manufacturing industry.

  13. Effect of extrinsic curvature on quark--hadron phase transition

    CERN Document Server

    Heydari-Fard, Malihe

    2009-01-01

    The last phase transition predicted by the standard model of particle physics took place at the QCD scale $T\\sim200$ MeV when the universe was about $t\\sim10^{-5}$ seconds old and the Hubble radius was around 10 Km. In this paper, we consider the quark--hadron phase transition in the context of brane-world cosmology where our universe is a 3-brane embedded in a $m$-dimensional bulk and localization of matter on the brane is achieved by means of a confining potential. We study the behavior of the physical quantities relevant to the description of the early universe like the energy density, temperature and scale factor, before, during, and after the phase transition and investigate the effects of extrinsic curvature on the cosmological phase transition. We show that the brane-world effects reduce the effective temperature of the quark--gluon plasma and of the hadronic fluid. Finally, we discuss the case where the universe evolved through a mixed phase with a small initial supercooling and monotonically growing ...

  14. [Swimming pool lung -- extrinsic allergic alveolitis or mycobacterial disease?].

    Science.gov (United States)

    Koschel, D; Pietrzyk, C; Sennekamp, J; Müller-Wening, D

    2006-05-01

    There have been several recent reports of pulmonary disease resulting from exposure to Mycobacterium avium complex in indoor hot tubs. The disease is thought to be due either to infection or extrinsic allergic alveolitis (EAA). In this report we describe the case of a patient who developed episodes of fever, dyspnea and cough 4-6 hours after cleaning his indoor swimming pool. A diagnosis of EAA was made on finding a restrictive lung function pattern with gas exchange abnormalities, a predominant lymphocytosis in the bronchoalveolar lavage, diffuse ground-glass opacities in the lower lobes on high-resolution computer tomography, and specific IgG antibody activity to the swimming pool water. There was no precipitin reaction or specific IgG antibody activity to microbes extracted from the water. Interestingly, the water contained Mycobacterium avium complex (MAC) in huge amounts and in this case the histopathological features of the lung biopsy specimens differed from those seen in typical EAA, but were similar to those described in "hot tub lung" caused by mycobacteria. Solely by avoidance of cleaning the swimming pool, without any pharmacological treatment, the patient recovered completely within three months. To the best of our knowledge, this is the first report of EAA possibly associated with MAC exposure in a swimming pool environment.

  15. Enabling complex genetic circuits to respond to extrinsic environmental signals.

    Science.gov (United States)

    Hoynes-O'Connor, Allison; Shopera, Tatenda; Hinman, Kristina; Creamer, John Philip; Moon, Tae Seok

    2017-03-06

    Genetic circuits have the potential to improve a broad range of metabolic engineering processes and address a variety of medical and environmental challenges. However, in order to engineer genetic circuits that can meet the needs of these real-world applications, genetic sensors that respond to relevant extrinsic and intrinsic signals must be implemented in complex genetic circuits. In this work, we construct the first AND and NAND gates that respond to temperature and pH, two signals that have relevance in a variety of real-world applications. A previously identified pH-responsive promoter and a temperature-responsive promoter were extracted from the E. coli genome, characterized, and modified to suit the needs of the genetic circuits. These promoters were combined with components of the type III secretion system in Salmonella typhimurium and used to construct a set of AND gates with up to 23-fold change. Next, an antisense RNA was integrated into the circuit architecture to invert the logic of the AND gate and generate a set of NAND gates with up to 1168-fold change. These circuits provide the first demonstration of complex pH- and temperature-responsive genetic circuits, and lay the groundwork for the use of similar circuits in real-world applications. Biotechnol. Bioeng. 2017;9999: 1-6. © 2017 Wiley Periodicals, Inc.

  16. Intrinsic and extrinsic rewards in a nonformal environmental education program.

    Science.gov (United States)

    Price, Emily A; Vining, Joanne; Saunders, Carol D

    2009-09-01

    Humans are surrounded by threats to the environment, many of their own making. The severity of environmental problems will not decrease unless action is taken to develop and encourage greater environmentally responsible behavior (ERB) in the general populace. Environmental education (EE) is one method for strengthening precursors to ERB such as knowledge and attitudes, but research on the connection is currently unclear. In this paper we present the results of a study investigating the role played by rewards in encouraging ERB precursors for adults and children involved in a zoo-based Nature Swap program. We used semistructured interviews to question 91 participants, including 38 children, 38 adult guardians, and 15 staff members regarding the importance of rewards in the program. We content analyzed the interviews to identify and describe major themes and then coded them. We found that adult guardians and Play Partners perceived intrinsic and extrinsic rewards as aiding in maintaining motivation and interest in the nonformal Nature Swap program. In addition, both children and adult companion participants in the program mentioned strengthened precursors to ERB. Overall we found that adult companions perceived that children who participated in the program spent more quality time outdoors and had a heightened awareness of their surroundings as a result of program-based rewards. Implications for other EE and conservation education programs are discussed.

  17. Iterative procedure for camera parameters estimation using extrinsic matrix decomposition

    Science.gov (United States)

    Goshin, Yegor V.; Fursov, Vladimir A.

    2016-03-01

    This paper addresses the problem of 3D scene reconstruction in cases when the extrinsic parameters (rotation and translation) of the camera are unknown. This problem is both important and urgent because the accuracy of the camera parameters significantly influences the resulting 3D model. A common approach is to determine the fundamental matrix from corresponding points on two views of a scene and then to use singular value decomposition for camera projection matrix estimation. However, this common approach is very sensitive to fundamental matrix errors. In this paper we propose a novel approach in which camera parameters are determined directly from the equations of the projective transformation by using corresponding points on the views. The proposed decomposition allows us to use an iterative procedure for determining the parameters of the camera. This procedure is implemented in two steps: the translation determination and the rotation determination. The experimental results of the camera parameters estimation and 3D scene reconstruction demonstrate the reliability of the proposed approach.

  18. Influence of exercise contraction mode and protein supplementation on human skeletal muscle satellite cell content and muscle fiber growth

    DEFF Research Database (Denmark)

    Farup, Jean; Rahbek, Stine Klejs; Riis, Simon

    2014-01-01

    -specific association between emergence of satellite cells (SCs), muscle growth, and remodeling in response to 12 wk unilateral resistance training performed as eccentric (Ecc) or concentric (Conc) resistance training ± whey protein (Whey, 19.5 g protein + 19.5 g glucose) or placebo (Placebo, 39 g glucose......Skeletal muscle satellite cells (SCs) are involved in remodeling and hypertrophy processes of skeletal muscle. However, little knowledge exists on extrinsic factors that influence the content of SCs in skeletal muscle. In a comparative human study, we investigated the muscle fiber type......) supplementation. Muscle biopsies (vastus lateralis) were analyzed for fiber type-specific SCs, myonuclei, and fiber cross-sectional area (CSA). Following training, SCs increased with Conc in both type I and type II fibers (P

  19. Receptor mechanisms of PAF mediated lymphatic constriction in the canine forelimb

    Directory of Open Access Journals (Sweden)

    D. E. Dobbins

    1992-01-01

    Full Text Available Platelet activating factor (PAF is a potent inflammatory lipid. In this study we assessed the ability of PAF to impact lymphatic vessel function by altering prenodal lymphatic resistance. Intralymphatic PAF (7.47 × 10−6, 7.47 × 10−5 and 7.47 × 10−4 M increased lymphatic perfusion pressure at the two highest infusion rates. PAF mediated lymphatic constriction was not altered by the intra-arterial infusion of phentolamine but was blocked by the intra-arterial infusion of the PAF receptor antagonist WEB 2170. These data indicate that in addition to PAF's effects on microvascular permeability, this agent may also impact the ability of the lymphatics to transport fluid through alterations in lymphatic smooth muscle tone. PAF mediated lymphatic constriction is not mediated by α-receptors but rather through PAF receptor mediated mechanism.

  20. Role of Smooth Muscle in Intestinal Inflammation

    Directory of Open Access Journals (Sweden)

    Stephen M Collins

    1996-01-01

    Full Text Available The notion that smooth muscle function is altered in inflammation is prompted by clinical observations of altered motility in patients with inflammatory bowel disease (IBD. While altered motility may reflect inflammation-induced changes in intrinsic or extrinsic nerves to the gut, changes in gut hormone release and changes in muscle function, recent studies have provided in vitro evidence of altered muscle contractility in muscle resected from patients with ulcerative colitis or Crohn’s disease. In addition, the observation that smooth muscle cells are more numerous and prominent in the strictured bowel of IBD patients compared with controls suggests that inflammation may alter the growth of intestinal smooth muscle. Thus, inflammation is associated with changes in smooth muscle growth and contractility that, in turn, contribute to important symptoms of IBD including diarrhea (from altered motility and pain (via either altered motility or stricture formation. The involvement of smooth muscle in this context may be as an innocent bystander, where cells and products of the inflammatory process induce alterations in muscle contractility and growth. However, it is likely that intestinal muscle cells play a more active role in the inflammatory process via the elaboration of mediators and trophic factors, including cytokines, and via the production of collagen. The concept of muscle cells as active participants in the intestinal inflammatory process is a new concept that is under intense study. This report summarizes current knowledge as it relates to these two aspects of altered muscle function (growth and contractility in the inflamed intestine, and will focus on mechanisms underlying these changes, based on data obtained from animal models of intestinal inflammation.

  1. A Dynamic Assignment of Extrinsic Information Distribution by a Frequency Means for Iterative Turbo Decoder

    Institute of Scientific and Technical Information of China (English)

    YANGFengfan

    2003-01-01

    In this paper, a new strategy for iterative turbo decoding is proposed, where a Generalized Gaussian distribution (GGD) is applied to model the statistical distributions of the extrinsic information generated by the component decoders. An Euclidean distance criterion is also introduced to choose a most likely candidate of the extrinsic information distribution before the each constituent decoding by a novel frequency means. The simulation results show that performance of an iterative decoder with this new technique surpasses the conventional Gaussian solution for the extrinsic information under the same channel conditions. Meanwhile, the evolution process of the extrinsic information density function can be tracked from iteration to iteration in the sense of the proposed criterion.

  2. Topological implications of the extrinsic curvature for the cosmological constant problem

    CERN Document Server

    Capistrano, Abraao J S

    2014-01-01

    The concept of smooth deformation of a Riemannian manifolds associated with the extrinsic curvature is explained and applied to FLRW cosmology. We show that such deformation can be derived from an Einstein-Hilbert-like dynamical principle producing an observable effect in the sense of Noether. The Gupta equations are used to address the problem of the cosmological constant to provide the expression of the function $b(t)$ which is a consequence of the effect of extrinsic curvature. When using such a modification, we notice on how the extrinsic curvature compensates both quantitative and qualitative difference between $ \\Lambda$ and $\\rho_{\\; vac}$ due to the topological characteristics of the extrinsic geometry. It is also shown that the coincidence problem can be alleviated in this framework.

  3. The detrimental effects of extrinsic reinforcement on “Intrinsic motivation”

    Science.gov (United States)

    Dickinson, Alyce M.

    1989-01-01

    Extrinsic consequences have been criticized on the grounds that they decrease intrinsic motivation or internally initiated behavior. Two popular rationales for this criticism, Lepper's overjustification hypothesis (1981) and Deci's motivational theory (Deci & Ryan, 1985), are reviewed and the criticism is then redefined behaviorally. “Intrinsically controlled” behavior is defined as behavior maintained by response-produced reinforcers, and the question concerning extrinsic consequences is thus restated as follows: When behavior is maintained by response-produced stimuli, does extrinsic reinforcement decrease the reinforcing value of those stimuli? The empirical support for this detrimental effect is summarized briefly, and several possible explanations for the phenomenon are offered. Research results that reflect on the effect's generality and social significance are discussed next, with the conclusion that the effect is transient and not likely to occur at all if extrinsic rewards are reinforcing, noncompetitive, based on reasonable performance standards, and delivered repetitively. PMID:22478013

  4. Time is on my side: time, general mental ability, human capital, and extrinsic career success.

    Science.gov (United States)

    Judge, Timothy A; Klinger, Ryan L; Simon, Lauren S

    2010-01-01

    The present study linked general mental ability (GMA) to extrinsic career success using a multilevel framework that included time and 3 possible time-based mediators of the GMA-career success relationship. Results, based on a large national sample, revealed that over a 28-year period, GMA affected growth in 2 indicators of extrinsic career success (income and occupational prestige), such that the careers of high-GMA individuals ascended more steeply over time than those of low-GMA individuals. Part of the reason high-GMA individuals had steeper growth in extrinsic success over time was because they attained more education, completed more job training, and gravitated toward more complex jobs. GMA also moderated the degree to which within-individual variation in the mediating variables affected within-individual variation in extrinsic career success over time: Education, training, and job complexity were much more likely to translate into career success for more intelligent individuals.

  5. First principles studies of extrinsic and intrinsic defects in boron nitride nanotubes

    CSIR Research Space (South Africa)

    Mashapa, MG

    2012-10-01

    Full Text Available Spin polarized density functional theory has been used to investigate the structural stability and electronic properties of extrinsic and intrinsic defects in boron nitride nanotubes. Carbon substitutional defects under nitrogen rich and boron...

  6. Relationships of Parental Behavior to "Disadvantaged" Children's Intrinsic-Extrinsic Motivation for Task Striving

    Science.gov (United States)

    Solomon, Daniel; Houlihan, Kevin A.

    1972-01-01

    In this study, the relevance of striving situations to intrinsic and extrinsic motivation was manipulated by varying the degree of involvement in the child's performance displayed by the experimenter. (Authors)

  7. Intrinsic and Extrinsic Motivation Among Adolescent Ten-Pin Bowlers in Kuala Lumpur, Malaysia

    National Research Council Canada - National Science Library

    Eng-Wah Teo; Selina Khoo; Rebecca Wong; Eng-Hoe Wee; Boon-Hooi Lim; Shabesan Sit Rengasamy

    2015-01-01

    .... The purpose of this study was to investigate different types of motivation (i.e., intrinsic vs. extrinsic) based on self-determination theory from the perspective of gender and the bowler type...

  8. MECHANISMS UNDERLYING CREATIVE PERFORMANCE: EMPLOYEE PERCEPTIONS OF INTRINSIC AND EXTRINSIC REWARDS FOR CREATIVITY

    National Research Council Canada - National Science Library

    Hye Jung Yoon; Sun Young Sung; Jin Nam Choi

    2015-01-01

      In this study, we clarified some of the ambiguities in the rewards-creativity relationship by focusing on creative performance in organizations that is contingent on intrinsic and extrinsic rewards...

  9. Consolidation power of extrinsic rewards: reward cues enhance long-term memory for irrelevant past events.

    Science.gov (United States)

    Murayama, Kou; Kitagami, Shinji

    2014-02-01

    Recent research suggests that extrinsic rewards promote memory consolidation through dopaminergic modulation processes. However, no conclusive behavioral evidence exists given that the influence of extrinsic reward on attention and motivation during encoding and consolidation processes are inherently confounded. The present study provides behavioral evidence that extrinsic rewards (i.e., monetary incentives) enhance human memory consolidation independently of attention and motivation. Participants saw neutral pictures, followed by a reward or control cue in an unrelated context. Our results (and a direct replication study) demonstrated that the reward cue predicted a retrograde enhancement of memory for the preceding neutral pictures. This retrograde effect was observed only after a delay, not immediately upon testing. An additional experiment showed that emotional arousal or unconscious resource mobilization cannot explain the retrograde enhancement effect. These results provide support for the notion that the dopaminergic memory consolidation effect can result from extrinsic reward.

  10. Optical phase modulator utilizing a transparent piezofilm for use with the extrinsic fiber interferometer

    Science.gov (United States)

    Sudarshanam, V. S.; Claus, Richard O.

    1993-03-01

    A piezoelectnc polyvinylidene flouride (PVF2) film with transparent indium tin oxide electrode metallization is placed directly in the path of a single mode fiber output, to form an extrinsic optical interferometer. This device can be used concurrently with another extrinsic inteferometer on a fiber directional coupler to generate a carrier phase modulation on which the signal phase shift is superimposed. Experimental results of the induced phase shifting coefficient are presented for two arrangements of the piezofilm differing in their boundary clamping conditions.

  11. Sulfasalazine-induced extrinsic allergic alveolitis in a patient with psoriatic arthritis.

    Science.gov (United States)

    Woltsche, M; Woltsche-Kahr, I; Roeger, G M; Aberer, W; Popper, H

    2001-11-20

    We report the first case of a well defined extrinsic allergic alveolitis as a complication of sulfasalazine therapy in a patient treated for psoriatic arthritis. CT of the chest showed small nodular densities over both lungs, BAL demonstrated a highly active lymphocytic alveolitis and transbronchial biopsies revealed lymphoplasmocytic interstitial infiltration. Sulfasalazine as causative agent was proven by an inadvertent rechallenge three years later and a positive lymphocyte transformation test. sulfasalazine; psoriatic arthritis; extrinsic allergic alveolitis

  12. Multiexciton complex from extrinsic centers in AlGaAs epilayers on Ge and Si substrates

    Energy Technology Data Exchange (ETDEWEB)

    Sarti, F.; Muñoz Matutano, G.; Bauer, D.; Dotti, N.; Vinattieri, A.; Gurioli, M., E-mail: gurioli@lens.unifi.it [Dipartimento di Fisica e Astronomia, LENS and CNISM, Università di Firenze, Via Sansone 1, I-50019 Firenze (Italy); Bietti, S.; Sanguinetti, S. [Dipartimento di Scienza dei Materiali and L-NESS, Università di Milano Bicocca, Via Cozzi 53, I-20125 Milano (Italy); Isella, G. [Dipartimento di Fisica and L-NESS, Politecnico di Milano, Via Anzani 42, 22100 Como (Italy)

    2013-12-14

    The multiexciton properties of extrinsic centers from AlGaAs layers on Ge and Si substrates are addressed. The two photon cascade is found both in steady state and in time resolved experiments. Polarization analysis of the photoluminescence provides clearcut attribution to neutral biexciton complexes. Our findings demonstrate the prospect of exploiting extrinsic centers for generating entangled photon pairs on a Si based device.

  13. A validity generalization procedure to test relations between intrinsic and extrinsic motivation and influence tactics.

    Science.gov (United States)

    Barbuto, John E; Moss, Jennifer A

    2006-08-01

    The relations of intrinsic and extrinsic motivation with use of consultative, legitimating, and pressure influence tactics were examined using validity generalization procedures. 5 to 7 field studies with cumulative samples exceeding 800 were used to test each relationship. Significance was found for relation between agents' intrinsic motivation and their use of consultative influence tactics and agents' extrinsic motivation and their use of legitimating influence tactics.

  14. Extrinsic Calibration for Vehicle-based Mobile Mapping System

    Directory of Open Access Journals (Sweden)

    SHI Limei

    2015-01-01

    Full Text Available Having the advantage of 360° imaging and rotation invariance, panoramic camera has gradually been used in mobile mapping systems(MMS. Calibration is an essential requirement to make sure that MMS can get high quality geo-information. This paper presents a way to address the extrinsic calibration for vehicle-based MMS composed of panoramic camera and Position and Orientation System (POS. Firstly, control points in the natural scene are set up, whose spatial coordinates are measured with high precision. Secondly, a panoramic spherical model is constructed and panoramic image can be projected to this model by means of spherical reverse transformation projection. Then, localize and select the control points in 3D spherical panoramic view but not in panoramic distorted image directly, the spherical coordinates of control points in panoramic image are gotten. After points correspondence is established, make use of direct geo-reference positioning equation and coordinate transformation, the translation and rotation parameters of panoramic camera relative to POS are computed. Experiments are conducted separately in space city calibration site located in Beijing and the Binhai New Area in Tianjin using our approach. Test results are listed as follows. When the GPS signal are of good quality, absolute positioning mean square error of a point is 10.3 cm in two-dimension plane and 16.5 cm in height direction; Otherwise, it is 35.4 cm in two-dimension plane and 54.8 cm in height direction. The max relative error of distance measurement is about 5 cm over a short distance (distance<3 km, which is not obviously affected by the GPS signal quality.

  15. Extrinsic information influences taste and flavor perception: a review from psychological and neuroimaging perspectives.

    Science.gov (United States)

    Okamoto, Masako; Dan, Ippeita

    2013-03-01

    The perception of taste and flavor can be greatly biased by extrinsic cues, or the information about a food that comes from outside of the food itself, such as package designs, brands, prices, and so on. In order to understand taste/flavor experiences in a broader context, it is necessary to consider factors other than the food/tastants themselves. This review aims to summarize some of the relevant findings from psychological and neuroimaging studies, focusing on depicting how extrinsic cues exert their effect on taste and flavor. Currently, the most frequently considered psychological mediator for the effects of extrinsic cues is expectation. Depending on the gap between expectation and taste/flavor experience, four major models predict outcomes of expectation effects: (1) assimilation, (2) generalized-negativity, (3) contrast, and (4) assimilation-contrast. Among them, the most influential is the assimilation model proposing that taste/flavor experiences are modified toward what one expects. Thus far, all the neuroimaging studies examining the influence of extrinsic cues have dealt with assimilation effects. They suggest that when extrinsic cues influence taste/flavor perception, cortical representations of taste/flavor are also modulated. Collectively neuroimaging findings partly answer questions arising from psychological aspects: the influence of extrinsic cues is not due to superficial response bias but to truly changed perception. These findings, albeit limited to assimilation effects, suggest that combined understanding from both psychological and neuroimaging studies would help deepen our understanding of the taste experience. Copyright © 2012. Published by Elsevier Ltd.

  16. Quantifying extrinsic noise in gene expression using the maximum entropy framework.

    Science.gov (United States)

    Dixit, Purushottam D

    2013-06-18

    We present a maximum entropy framework to separate intrinsic and extrinsic contributions to noisy gene expression solely from the profile of expression. We express the experimentally accessible probability distribution of the copy number of the gene product (mRNA or protein) by accounting for possible variations in extrinsic factors. The distribution of extrinsic factors is estimated using the maximum entropy principle. Our results show that extrinsic factors qualitatively and quantitatively affect the probability distribution of the gene product. We work out, in detail, the transcription of mRNA from a constitutively expressed promoter in Escherichia coli. We suggest that the variation in extrinsic factors may account for the observed wider-than-Poisson distribution of mRNA copy numbers. We successfully test our framework on a numerical simulation of a simple gene expression scheme that accounts for the variation in extrinsic factors. We also make falsifiable predictions, some of which are tested on previous experiments in E. coli whereas others need verification. Application of the presented framework to more complex situations is also discussed.

  17. The interplay of intrinsic and extrinsic bounded noises in biomolecular networks.

    Directory of Open Access Journals (Sweden)

    Giulio Caravagna

    Full Text Available After being considered as a nuisance to be filtered out, it became recently clear that biochemical noise plays a complex role, often fully functional, for a biomolecular network. The influence of intrinsic and extrinsic noises on biomolecular networks has intensively been investigated in last ten years, though contributions on the co-presence of both are sparse. Extrinsic noise is usually modeled as an unbounded white or colored gaussian stochastic process, even though realistic stochastic perturbations are clearly bounded. In this paper we consider Gillespie-like stochastic models of nonlinear networks, i.e. the intrinsic noise, where the model jump rates are affected by colored bounded extrinsic noises synthesized by a suitable biochemical state-dependent Langevin system. These systems are described by a master equation, and a simulation algorithm to analyze them is derived. This new modeling paradigm should enlarge the class of systems amenable at modeling. We investigated the influence of both amplitude and autocorrelation time of a extrinsic Sine-Wiener noise on: (i the Michaelis-Menten approximation of noisy enzymatic reactions, which we show to be applicable also in co-presence of both intrinsic and extrinsic noise, (ii a model of enzymatic futile cycle and (iii a genetic toggle switch. In (ii and (iii we show that the presence of a bounded extrinsic noise induces qualitative modifications in the probability densities of the involved chemicals, where new modes emerge, thus suggesting the possible functional role of bounded noises.

  18. Structural Coupling of Extrinsic Proteins with the Oxygen-Evolving Center in Photosystem II

    Directory of Open Access Journals (Sweden)

    Kentaro eIfuku

    2016-02-01

    Full Text Available Photosystem II (PSII, which catalyzes photosynthetic water oxidation, is composed of more than 20 subunits, including membrane-intrinsic and -extrinsic proteins. The PSII extrinsic proteins shield the catalytic Mn4CaO5 cluster from the outside bulk solution and enhance binding of inorganic cofactors, such as Ca2+ and Cl-, in the oxygen-evolving center (OEC of PSII. Among PSII extrinsic proteins, PsbO is commonly found in all oxygenic organisms, while PsbP and PsbQ are specific to higher plants and green algae, and PsbU, PsbV, CyanoQ, and CyanoP exist in cyanobacteria. In addition, red algae and diatoms have unique PSII extrinsic proteins, such as PsbQ’ and Psb31, suggesting functional divergence during evolution. Recent studies with reconstitution experiments combined with Fourier transform infrared spectroscopy have revealed how the individual PSII extrinsic proteins affect the structure and function of the OEC in different organisms. In this review, we summarize our recent results and discuss changes that have occurred in the structural coupling of extrinsic proteins with the OEC during evolutionary history.

  19. Muscle biopsy

    Science.gov (United States)

    ... Inflammatory diseases of muscle (such as polymyositis or dermatomyositis ) Diseases of the connective tissue and blood vessels ( ... disease that involves inflammation and a skin rash ( dermatomyositis ) Inherited muscle disorder ( Duchenne muscular dystrophy ) Inflammation of ...

  20. Muscle atrophy

    Science.gov (United States)

    ... atrophy. Exercises may include ones done in a swimming pool to reduce the muscle workload, and other types ... a physical examination and ask about your medical history and symptoms, including: When did the muscle atrophy ...

  1. Median and ulnar nerve compression at the wrist caused by anomalous muscles.

    Science.gov (United States)

    De Smet, L

    2002-12-01

    Compression of the median and ulnar nerves at the wrist is frequently encountered. Carpal tunnel syndrome usually occurs without any obvious extrinsic cause; several cases have however been reported caused by anomalous or hypertrophic muscles. A survey of the literature shows that compression neuropathy of the median nerve has been reported in relation with anomalies affecting three muscles: the first (or second) lumbrical, the palmaris longus and its anatomic variants and the superficial flexor of the index finger. In the ulnar tunnel the situation is thoroughly different: so-called idiopathic ulnar tunnel syndrome is rare and an extrinsic compressing structure can usually be disclosed. Anomalous muscles belong to the palmaris longus/abductor digiti minimi group; the flexor carpi ulnaris is sometimes involved. One can suspect the presence of such an anomalous muscle when the compression syndrome concerns a patient who is not within the "usual" age group with symptoms initiated or aggravated by physical exercise.

  2. Your Muscles

    Science.gov (United States)

    ... develops. There they help to push the baby out of the mother's body when it's time to be born. You'll find smooth muscles at work behind the scenes in your eyes, too. These muscles keep the eyes ... thick muscles of the heart contract to pump blood out and then relax to let blood back in ...

  3. Modeling Muscles

    Science.gov (United States)

    Goodwyn, Lauren; Salm, Sarah

    2007-01-01

    Teaching the anatomy of the muscle system to high school students can be challenging. Students often learn about muscle anatomy by memorizing information from textbooks or by observing plastic, inflexible models. Although these mediums help students learn about muscle placement, the mediums do not facilitate understanding regarding integration of…

  4. Evidence for metabolic abnormalities in the muscles of patients with fibromyalgia.

    Science.gov (United States)

    Park, J H; Niermann, K J; Olsen, N

    2000-04-01

    Widespread muscle pain, fatigue, and weakness are defining characteristics of patients with fibromyalgia (FM). The aim of this review is to summarize recent investigations of muscle abnormalities in FM, which can be classified as structural, metabolic, or functional in nature. Histologic muscle abnormalities of membranes, mitochondria, and fiber type have been well described at both the light microscopic and ultrastructural levels. These structural abnormalities often correlate with biochemical abnormalities, defective energy production, and the resultant dysfunction of FM muscles. The observed abnormalities in FM muscles are consistent with neurologic findings and disturbances in the hypothalamic-pituitary-adrenal axis. Functional changes in FM muscles are assessed most directly by strength and endurance measurements, but pain and psychologic factors may interfere with accurate assessments. To compensate for diminished effort, the decreased efficiency of the work performance by patients with FM can be verified from P-31 magnetic resonance spectroscopy (MRS) data by calculation of the work/energy-cost ratio for various tasks. In the disease course, muscle abnormalities may be elicited by intrinsic changes within the muscle tissue itself and/or extrinsic neurologic and endocrine factors. The accurate assignment of intrinsic or extrinsic factors has been substantially clarified by a recent surge of experimental findings. Irrespective of the multifaceted causes of muscle dysfunction and pain, an in-depth understanding of the muscle defects may provide ideas for characterization of the underlying pathogenesis and development of new therapeutic approaches for fibromyalgia syndrome.

  5. Protein dynamics in skeletal muscle after trauma: local and systemic effects.

    Science.gov (United States)

    Downey, R S; Monafo, W W; Karl, I E; Matthews, D E; Bier, D M

    1986-03-01

    Injury is attended by accelerated skeletal muscle proteolysis. Accurate definition of this hypercatabolic response and its mediation is requisite for specific therapy. We measured protein dynamics in the incubated and intact epitrochlearis and soleus muscles excised from both forelimbs and both hindlimbs of rats 4 days after injury by either a single hind limb scald (90 degrees C water for 3 seconds; metabolic rate (MR) + 15%, urinary urea nitrogen (UUN) + 10%) or a 5% excision (dorsal skin removed to fascia; MR + 40%, UUN + 90%). Protein synthesis (3H phenylalanine incorporation) increased only in the injured soleus from the scalded hind limb (+100%). Actin and myosin breakdown (3-methylhistidine release) increased in all muscles tested and was consistently larger in epitrochlearis than in soleus muscles. Breakdown of the mixed protein pool (tyrosine release) increased but less so than 3-methylhistidine and did not reach significance in the uninjured soleus muscle of scalded rats. With respect to fiber type, white fiber epitrochlearis muscle demonstrated a more pronounced elevation of both measures of breakdown but at a lower metabolic rate than did red fiber soleus muscle. Increasing MR was associated with a linear increase in soleus proteolysis but no further change in epitrochlearis breakdown. We conclude that protein breakdown is increased in skeletal muscle distant from injury; however, even when metabolic stress is severe, synthesis is unchanged. Muscles of different fiber composition are not equally labile. Furthermore, myofibrillar protein is more labile than the mixed protein pool.

  6. Changes in contractile properties by androgen hormones in sexually dimorphic muscles of male frogs (Xenopus laevis).

    Science.gov (United States)

    Regnier, M; Herrera, A A

    1993-02-01

    1. Male frogs (Xenopus laevis) were castrated then given either empty or testosterone-filled implants to produce animals with low or high levels of circulating testosterone. Eight weeks later the contractile properties of an androgen-sensitive forelimb flexor, the flexor carpi radialis muscle (FCR), were measured in vitro. Another forelimb flexor muscle, the coracoradialis, and a hindlimb muscle, the iliofibularis, were analysed similarly. 2. Plasma testosterone levels were 0.9 +/- 0.3 ng/ml (+/- S.E.M.) in castrated frogs with blank implants (C) and 61.3 +/- 4.7 ng/ml in castrates with testosterone implants (CT). Unoperated males, sampled at various times of the year, ranged between 10.8 and 51.0 ng/ml. 3. With direct electrical stimulation of the FCR, contraction time of the isometric twitch was not affected by testosterone levels. Relaxation times were affected, however. Half- and 90% relaxation times were 27 and 42% longer, respectively, for CT compared to C muscles. 4. Testosterone also had no effect on the contraction time of twitches elicited by stimulation of the FCR nerve. Half- and 90% relaxation times were 51 and 76% longer, respectively, for CT compared to C muscles. 5. Tetanus tension, elicited by direct stimulation of the FCR at 50 Hz, was 86% greater in CT compared to C muscles. The average cross-sectional area of FCR muscle fibres was 84% greater in CT muscles. These results implied that testosterone treatment had no effect on specific muscle tension. 6. Stimulation of the FCR nerve at 50 Hz resulted in 53% less tension than the same stimulus applied directly to CT muscles. In C muscles the difference was only 14%. This suggested that testosterone treatment reduced synaptic efficacy. 7. In CT muscles, direct or nerve stimulation of fibres in the shoulder region of the FCR elicited twitches that contracted and relaxed more slowly than fibres in the elbow region. In C muscles there was no difference in contraction or relaxation time between fibres in

  7. Predictors of employment in schizophrenia: The importance of intrinsic and extrinsic motivation.

    Science.gov (United States)

    Reddy, L Felice; Llerena, Katiah; Kern, Robert S

    2016-10-01

    Unemployment is a primary functional deficit for the majority of adults with schizophrenia. Research indicates that over two-thirds of adults living in the community with schizophrenia are unemployed. Despite effective programs to assist with job identification and placement, the ability to attain and maintain employment remains a pressing concern. A contributing factor that may be relevant but has received little attention in the work rehabilitation literature is motivation. People with schizophrenia show marked deficits in both intrinsic and extrinsic motivation but these deficits have not been directly examined in relation to work outcomes. The present study sought to examine the relationship between intrinsic and extrinsic motivation and work outcome among a sample of 65 adults with schizophrenia enrolled in a supported employment program. One-third of the participants in the study obtained work. Intrinsic motivation related to valuing and feeling useful in a work role significantly predicted who would obtain employment. Extrinsic motivation related to gaining rewards and avoiding obstacles showed a non-significant trend-level relationship such that workers had higher extrinsic motivation than nonworkers. These findings highlight the importance of considering both intrinsic and extrinsic motivation in work-related interventions and supported employment for individuals with schizophrenia. The results are discussed in terms of clinical implications for improving rehabilitation and occupational outcomes in schizophrenia. Published by Elsevier B.V.

  8. Physiological features of the opercularis muscle and their effects on vibration sensitivity in the bullfrog Rana catesbeiana.

    Science.gov (United States)

    Hetherington, T E

    1987-09-01

    The amphibian opercularis muscle connects a movable otic element (the operculum) to the pectoral girdle and can act in reception of ground vibrations. Various physiological parameters of the opercularis muscle of the bullfrog Rana catesbeiana were measured and compared with similar measurements on the iliofibularis muscle of the hindlimb. The opercularis muscle is a very slowly contracting muscle, with a Vmax of 1.81 muscle lengths s-1 compared to a Vmax of 6.24 muscle lengths s-1 for the iliofibularis muscle. The opercularis muscle develops tension slowly, taking about 10 s to attain maximum isometric tension when stimulated at 100 Hz. The muscle can retain high levels of tension for several minutes, and following stimulation has a time to half-relaxation of about 4-6 s. The slow velocity of contraction, slow rate of tension development, fatigue-resistance and slow rate of relaxation of the opercularis muscle support morphological evidence that it consists mostly of tonic muscle fibres. Experiments were also made to examine the effects of muscle tension on reception of ground vibrations as measured by inner ear microphonics. Severing the nerve supplying the opercularis muscle produced slight decreases of no more than 2 dB in responses to vibrations from 25 to 200 Hz. Artificial stimulation of the opercularis muscle after severing the nerve supplying the muscle increased responses to vibration across the entire frequency range. Higher tension levels produced greater increases in responses; at the highest tensions used (about 120 kN m-2) responses were increased by as much as 4.5 dB. The opercularis muscle is therefore specialized for slow but prolonged contractions, and tension is important in its sensory function. A tensed opercularis muscle appears to transmit faithfully motion of the forelimb, produced by vibrations, to the operculum such that the latter moves relative to the inner ear fluids.

  9. A sliced inverse regression (SIR decoding the forelimb movement from neuronal spikes in the rat motor cortex

    Directory of Open Access Journals (Sweden)

    Shih-Hung Yang

    2016-12-01

    Full Text Available Several neural decoding algorithms have successfully converted brain signals into commands to control a computer cursor and prosthetic devices. A majority of decoding methods, such as population vector algorithms (PVA, optimal linear estimators (OLE, and neural networks (NN, are effective in predicting movement kinematics, including movement direction, speed and trajectory but usually require a large number of neurons to achieve desirable performance. This study proposed a novel decoding algorithm even with signals obtained from a smaller numbers of neurons. We adopted sliced inverse regression (SIR to predict forelimb movement from single-unit activities recorded in the rat primary motor (M1 cortex in a water-reward lever-pressing task. SIR performed weighted principal component analysis (PCA to achieve effective dimension reduction for nonlinear regression. To demonstrate the decoding performance, SIR was compared to PVA, OLE, and NN. Furthermore, PCA and sequential feature selection (SFS which are popular feature selection techniques were implemented for comparison of feature selection effectiveness. Among SIR, PVA, OLE, PCA, SFS, and NN decoding methods, the trajectories predicted by SIR (with a root mean square error, RMSE, of 8.47 ± 1.32 mm was closer to the actual trajectories compared with those predicted by PVA (30.41 ± 11.73 mm, OLE (20.17 ± 6.43 mm, PCA (19.13 ± 0.75 mm, SFS (22.75 ± 2.01 mm, and NN (16.75 ± 2.02 mm. The superiority of SIR was most obvious when the sample size of neurons was small. We concluded that SIR sorted the input data to obtain the effective transform matrices for movement prediction, making it a robust decoding method for conditions with sparse neuronal information.

  10. Enhanced Thalamic Functional Connectivity with No fMRI Responses to Affected Forelimb Stimulation in Stroke-Recovered Rats

    Science.gov (United States)

    Shim, Woo H.; Suh, Ji-Yeon; Kim, Jeong K.; Jeong, Jaeseung; Kim, Young R.

    2017-01-01

    Neurological recovery after stroke has been extensively investigated to provide better understanding of neurobiological mechanism, therapy, and patient management. Recent advances in neuroimaging techniques, particularly functional MRI (fMRI), have widely contributed to unravel the relationship between the altered neural function and stroke-affected brain areas. As results of previous investigations, the plastic reorganization and/or gradual restoration of the hemodynamic fMRI responses to neural stimuli have been suggested as relevant mechanisms underlying the stroke recovery process. However, divergent study results and modality-dependent outcomes have clouded the proper interpretation of variable fMRI signals. Here, we performed both evoked and resting state fMRI (rs-fMRI) to clarify the link between the fMRI phenotypes and post-stroke functional recovery. The experiments were designed to examine the altered neural activity within the contra-lesional hemisphere and other undamaged brain regions using rat models with large unilateral stroke, which despite the severe injury, exhibited nearly full recovery at ∼6 months after stroke. Surprisingly, both blood oxygenation level-dependent and blood volume-weighted (CBVw) fMRI activities elicited by electrical stimulation of the stroke-affected forelimb were completely absent, failing to reveal the neural origin of the behavioral recovery. In contrast, the functional connectivity maps showed highly robust rs-fMRI activity concentrated in the contra-lesional ventromedial nucleus of thalamus (VM). The negative finding in the stimuli-induced fMRI study using the popular rat middle cerebral artery model denotes weak association between the fMRI hemodynamic responses and neurological improvement. The results strongly caution the indiscreet interpretation of stroke-affected fMRI signals and demonstrate rs-fMRI as a complementary tool for efficiently characterizing stroke recovery. PMID:28119575

  11. Extrinsic Contribution and Instability Properties in Lead-Based and Lead-Free Piezoceramics

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    José Eduardo García

    2015-11-01

    Full Text Available Piezoceramic materials generally exhibit a notable instability of their functional properties when they work under real external conditions. This undesirable effect, known as nonlinear behavior, is mostly associated with the extrinsic contribution to material response. In this article, the role of the ferroelectric domain walls’ motion in the nonlinear response in the most workable lead-based and lead-free piezoceramics is reviewed. Initially, the extrinsic origin of the nonlinear response is discussed in terms of the temperature dependence of material response. The influence of the crystallographic phase and of the phase boundaries on the material response are then reviewed. Subsequently, the impact of the defects created by doping in order to control the extrinsic contribution is discussed as a way of tuning material properties. Finally, some aspects related to the grain-size effect on the nonlinear response of piezoceramics are surveyed.

  12. Intrinsic and extrinsic mechanical properties related to the differentiation of mesenchymal stem cells.

    Science.gov (United States)

    Lee, Jin-Ho; Park, Hun-Kuk; Kim, Kyung Sook

    2016-05-06

    Diverse intrinsic and extrinsic mechanical factors have a strong influence on the regulation of stem cell fate. In this work, we examined recent literature on the effects of mechanical environments on stem cells, especially on differentiation of mesenchymal stem cells (MSCs). We provide a brief review of intrinsic mechanical properties of single MSC and examined the correlation between the intrinsic mechanical property of MSC and the differentiation ability. The effects of extrinsic mechanical factors relevant to the differentiation of MSCs were considered separately. The effect of nanostructure and elasticity of the matrix on the differentiation of MSCs were summarized. Finally, we consider how the extrinsic mechanical properties transfer to MSCs and then how the effects on the intrinsic mechanical properties affect stem cell differentiation.

  13. The Path Taken: Consequences of Attaining Intrinsic and Extrinsic Aspirations in Post-College Life.

    Science.gov (United States)

    Niemiec, Christopher P; Ryan, Richard M; Deci, Edward L

    2009-06-01

    Life goals, or aspirations, organize and direct behavior over extended periods of time. The present study, guided by self-determination theory, examined the consequences of pursuing and attaining aspirations over a one-year period in a post-college sample. Results indicated that placing importance on either intrinsic or extrinsic aspirations related positively to attainment of those goals. Yet, whereas attainment of intrinsic aspirations related positively to psychological health, attainment of extrinsic aspirations did not; indeed, attainment of extrinsic aspirations related positively to indicators of ill-being. Also as predicted, the association between change in attainment of intrinsic aspirations and change in psychological health was mediated by change in the satisfaction of the basic psychological needs for autonomy, competence, and relatedness. Discussion focuses on the idea that not all goal attainment is beneficial; rather, attainment of aspirations with different contents relates differentially to psychological health.

  14. Dissipationless spin-Hall current contribution in the extrinsic spin-Hall effect

    Institute of Scientific and Technical Information of China (English)

    Yan Yu-Zhen; Li Hui-Wu; Hu Liang-Bin

    2009-01-01

    This paper shows that a substantial amount of dissipationless spin-Hall current contribution may exist in the extrinsic spin-Hall effect, which originates from the spin-orbit coupling induced by the applied external electric field itself that drives the extrinsic spin-Hall effect in a nonmagnetic semiconductor (or metal). By assuming that the impurity density is in a moderate range such that the total scattering potential due to all randomly distributed impurities is a smooth function of the space coordinate, it is shown that this dissipationless contribution shall be of the same orders of magnitude as the usual extrinsic contribution from spin-orbit dependent impurity scatterings (or may even be larger than the latter one). The theoretical results obtained are in good agreement with recent relevant experimental results.

  15. Sensory representation and learning-related plasticity in mushroom body extrinsic feedback neurons of the protocerebral tract.

    Science.gov (United States)

    Haehnel, Melanie; Menzel, Randolf

    2010-01-01

    Gamma-aminobutyric acid immunoreactive feedback neurons of the protocerebral tract are a major component of the honeybee mushroom body. They have been shown to be subject to learning-related plasticity and provide putative inhibitory input to Kenyon cells and the pedunculus extrinsic neuron, PE1. We hypothesize, that learning-related modulation in these neurons is mediated by varying the amount of inhibition provided by feedback neurons. We performed Ca(2+) imaging recordings of populations of neurons of the protocerebral-calycal tract (PCT) while the bees were conditioned in an appetitive olfactory paradigm and their behavioral responses were quantified using electromyographic recordings from M17, the muscle which controls the proboscis extension response. The results corroborate findings from electrophysiological studies showing that PCT neurons respond to sucrose and odor stimuli. The odor responses are concentration dependent. Odor and sucrose responses are modulated by repeated stimulus presentations. Furthermore, animals that learned to associate an odor with sucrose reward responded to the repeated presentations of the rewarded odor with less depression than they did to an unrewarded and a control odor.

  16. The relationship between extrinsic motivation, job satisfaction and life satisfaction amongst employees in a public organisation

    Directory of Open Access Journals (Sweden)

    Chengedzai Mafini

    2014-02-01

    Full Text Available Orientation: There is much research on extrinsic motivation, job satisfaction and life satisfaction in organisations. However, empirical evidence on how such factors affect employees in public organisations in developing countries is lacking.Research purpose: To examine the relationships between extrinsic motivation, job satisfaction and life satisfaction amongst employees in a public organisation.Motivation for the study: Labour strife is an endemic phenomenon in South Africa’s public sector as evidenced by the high incidences of industrial action and labour turnover. This study contributes to this subject by identifying the extrinsic factors that could be optimised with a view to enhancing job and life satisfaction amongst government employees.Research approach, design and method: The study used the quantitative research survey approach: a questionnaire was administered to 246 employees in a South African public organisation. Extrinsic motivation factors were identified using principal components analysis. Mean score ranking was used to compare the relative importance of all factors. The conceptual framework was tested using Spearman’s rank correlation analysis and linear regression analysis.Main findings: Statistically significant relationships were observed between job satisfaction and four extrinsic motivation factors: remuneration, quality of work life, supervision and teamwork. The relationship with promotion was insignificant, but a statistically significant relationship was established with life satisfaction.Practical/managerial implications: The findings may be used to implement strategies for enhancing employee performance and industrial relations within public organisations.Contribution/value-add: The study provides evidence of the interplay between extrinsic motivation, job satisfaction and life satisfaction for public servants in developing countries.

  17. Computer tomographic patterns in extrinsic allergic alveolitis - a comparison with conventional radiological findings

    Energy Technology Data Exchange (ETDEWEB)

    Hieckel, H.G.; Mueller, S.; Luening, M.

    1986-10-01

    Seventeen patients with extrinsic allergic alveolitis or bird-fancier's lung were examined by standard radiological techniques and classified after Hapke's classification. In addition, the patients were examined by CT. The CT patterns have been analysed and compared with standard radiological findings. The methodological advantages of CT are discussed. Radiological investigation is of limited value in the diagnosis of extrinsic allergic alveolitis. Conventional radiography remains the standard of initial X-ray examination. In early cases, however, CT may be a valuable addition within the diagnostic strategy of a diagnostic imaging department.

  18. Substance use by college students: the role of intrinsic versus extrinsic motivation for athletic involvement.

    Science.gov (United States)

    Rockafellow, Bradley D; Saules, Karen K

    2006-09-01

    Certain types of athletic involvement may confer risk for substance use by college students. This study investigated whether motivational factors play a role in the relationship between athletic involvement and substance use. Intercollegiate athletes (n=98) and exercisers (n=120) were surveyed about substance use and motivation for athletic involvement. Athletes and exercisers who were extrinsically motivated had significantly higher rates of alcohol use than their intrinsically motivated counterparts. Results suggest that college students who are extrinsically motivated for involvement in physical activity/athletics--particularly those involved in team sports--may be in need of targeted prevention efforts. ((c) 2006 APA, all rights reserved).

  19. Motor cortex electrical stimulation promotes axon outgrowth to brain stem and spinal targets that control the forelimb impaired by unilateral corticospinal injury.

    Science.gov (United States)

    Carmel, Jason B; Kimura, Hiroki; Berrol, Lauren J; Martin, John H

    2013-04-01

    We previously showed that electrical stimulation of motor cortex (M1) after unilateral pyramidotomy in the rat increased corticospinal tract (CST) axon length, strengthened spinal connections, and restored forelimb function. Here, we tested: (i) if M1 stimulation only increases spinal axon length or if it also promotes connections to brain stem forelimb control centers, especially magnocellular red nucleus; and (ii) if stimulation-induced increase in axon length depends on whether pyramidotomy denervated the structure. After unilateral pyramidotomy, we electrically stimulated the forelimb area of intact M1, to activate the intact CST and other corticofugal pathways, for 10 days. We anterogradely labeled stimulated M1 and measured axon length using stereology. Stimulation increased axon length in both the spinal cord and magnocellular red nucleus, even though the spinal cord is denervated by pyramidotomy and the red nucleus is not. Stimulation also promoted outgrowth in the cuneate and parvocellular red nuclei. In the spinal cord, electrical stimulation caused increased axon length ipsilateral, but not contralateral, to stimulation. Thus, stimulation promoted outgrowth preferentially to the sparsely corticospinal-innervated and impaired side. Outgrowth resulted in greater axon density in the ipsilateral dorsal horn and intermediate zone, resembling the contralateral termination pattern. Importantly, as in spinal cord, increase in axon length in brain stem also was preferentially directed towards areas less densely innervated by the stimulated system. Thus, M1 electrical stimulation promotes increases in corticofugal axon length to multiple M1 targets. We propose the axon length change was driven by competition into an adaptive pattern resembling lost connections. © 2013 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

  20. Direct muscle neurotization after end-to end and end-to-side neurorrhaphy

    Science.gov (United States)

    Papalia, Igor; Ronchi, Giulia; Muratori, Luisa; Mazzucco, Alessandra; Magaudda, Ludovico; Geuna, Stefano

    2012-01-01

    The need for the continuous research of new tools for improving motor function recovery after nerve injury is justified by the still often unsatisfactory clinical outcome in these patients. It has been previously shown that the combined use of two reconstructive techniques, namely end-to-side neurorrhaphy and direct muscle neurotization in the rat hindlimb model, can lead to good results in terms of skeletal muscle reinnervation. Here we show that, in the rat forelimb model, the combined use of direct muscle neurotization with either end-to-end or end-to-side neurorrhaphy to reinnervate the denervated flexor digitorum muscles, leads to muscle atrophy prevention over a long postoperative time lapse (10 months). By contrast, very little motor recovery (in case of end-to-end neurorrhaphy) and almost no motor recovery (in case of end-to-side neurorrhaphy) were observed in the grasping activity controlled by flexor digitorum muscles. It can thus be concluded that, at least in the rat, direct muscle neurotization after both end-to-end and end-to-side neurorrhaphy represents a good strategy for preventing denervation-related muscle atrophy but not for regaining the lost motor function. PMID:25538749

  1. Cell-extrinsic defective lymphocyte development in Lmna(-/- mice.

    Directory of Open Access Journals (Sweden)

    J Scott Hale

    Full Text Available BACKGROUND: Mutations in the LMNA gene, which encodes all A-type lamins, result in a variety of human diseases termed laminopathies. Lmna(-/- mice appear normal at birth but become runted as early as 2 weeks of age and develop multiple tissue defects that mimic some aspects of human laminopathies. Lmna(-/- mice also display smaller spleens and thymuses. In this study, we investigated whether altered lymphoid organ sizes are correlated with specific defects in lymphocyte development. PRINCIPAL FINDINGS: Lmna(-/- mice displayed severe age-dependent defects in T and B cell development which coincided with runting. Lmna(-/- bone marrow reconstituted normal T and B cell development in irradiated wild-type recipients, driving generation of functional and self-MHC restricted CD4(+ and CD8(+ T cells. Transplantation of Lmna(-/- neonatal thymus lobes into syngeneic wild-type recipients resulted in good engraftment of thymic tissue and normal thymocyte development. CONCLUSIONS: Collectively, these data demonstrate that the severe defects in lymphocyte development that characterize Lmna(-/- mice do not result directly from the loss of A-type lamin function in lymphocytes or thymic stroma. Instead, the immune defects in Lmna(-/- mice likely reflect indirect damage, perhaps resulting from prolonged stress due to the striated muscle dystrophies that occur in these mice.

  2. Work Motivation and the Negative Effects of Extrinsic Rewards: A Reward With Implications for Theory and Practice

    Science.gov (United States)

    Notz, William W.

    1975-01-01

    Summarizes and discusses findings on two hypotheses predicting interaction between intrinsic and extrinsic motivation: extrinsic rewards are those which provide satisfaction independent of the actual activity itself and are controlled by someone other than the employee, whereas intrinsic rewards are those over which the employee has a high degree…

  3. Atomic force microscopy study of the rabbit skeletal muscle ryanodine receptors in different functional states

    Institute of Scientific and Technical Information of China (English)

    魏青青; 程晓阳; 陈克樱; 胡钧; 李民乾; 朱培闳

    2002-01-01

    Atomic force microscope was applied to investigate the effect of extrinsic phospholipid on the structure of rabbit skeletal muscle ryanodine receptor/calcium release channel (RyR1). In addition, in the presence of extrinsic phospholipid, the height and elasticity of the RyR1s in different functional states were also measured. The results indicate: (i) most of the RyR1s showed a normal structure only in the presence of extrinsic phospholipid; (ii) treatment of the RyR1s with AMP and Ca2+ together could increase their Young's Modulus but not change their apparent height; (iii) no detectable change in either height or Young's Modulus of the RyR1s appeared, if the RyR1s were treated with other activators or inhibitors.

  4. Extrinsic Motivation as Correlates of Work Attitude of the Nigerian Police Force: Implications for Counselling

    Science.gov (United States)

    Igun, Sylvester Nosakhare

    2008-01-01

    The study examined Extrinsic motivation as correlates of work attitude of the Nigeria Police Force and its implications for counselling. 300 Police personnel were selected by random sampling technique from six departments that make up police force Headquarters, Abuja. The personnel were selected from each department using simple sampling…

  5. Extrinsic functions of lectin domains in O-N-acetylgalactosamine glycan biosynthesis

    DEFF Research Database (Denmark)

    Lorenz, Virginia; Ditamo, Yanina; Cejas, Romina B;

    2016-01-01

    Glycan biosynthesis occurs mainly in Golgi. Molecular organization and functional regulation of this process are not well understood. We evaluated the extrinsic effect of lectin domains (β-trefoil fold) of polypeptide GalNAc-transferases (ppGalNAc-Ts) on catalytic activity of glycosyltransferases...

  6. Perceived Constraints on Recreational Sport Participation: Investigating Their Relationship with Intrinsic Motivation, Extrinsic Motivation and Amotivation.

    Science.gov (United States)

    Alexandris, Konstantinos; Tsorbatzoudis, Charalambos; Grouios, George

    2002-01-01

    Investigated the influence of constraint dimensions on intrinsic motivation, extrinsic motivation, and amotivation among Greek adults who reported participation in some type of sport and physical activity. Data from the Sport Motivation Scale and leisure constraints questionnaire revealed that intrapersonal constraints acted as de-motivating…

  7. Tangible and Intangible Rewards and Employee Creativity: The Mediating Role of Situational Extrinsic Motivation

    Science.gov (United States)

    Yoon, Hye Jung; Sung, Sun Young; Choi, Jin Nam; Lee, Kyungmook; Kim, Seongsu

    2015-01-01

    This study examined the effects of tangible and intangible forms of creativity-contingent rewards on employee creativity. Situation-specific intrinsic and extrinsic motivations were proposed as mediators of the reward-creativity link. Based on data collected from 271 employees and their supervisors, results revealed the following: (a) intangible…

  8. A Novel Extrinsic Fiber-Optic Fabry-Perot Strain Sensor System Based on Optical Amplification

    Institute of Scientific and Technical Information of China (English)

    Yun-Jiang Rao; Jian Jiang; Zheng-Lin Ran

    2003-01-01

    A novel extrinsic fiber-optic Fabry-Perot interferometric strain sensor system is demonstrated based on the simultaneous use of the amplified spontaneous emission and optical amplification. The improvement of 3~4 orders of magnitude in signal level can be achieved.

  9. A Quantitative Analysis of the Extrinsic and Intrinsic Turnover Factors of Relational Database Support Professionals

    Science.gov (United States)

    Takusi, Gabriel Samuto

    2010-01-01

    This quantitative analysis explored the intrinsic and extrinsic turnover factors of relational database support specialists. Two hundred and nine relational database support specialists were surveyed for this research. The research was conducted based on Hackman and Oldham's (1980) Job Diagnostic Survey. Regression analysis and a univariate ANOVA…

  10. The fragmented self : imbalance between intrinsic and extrinsic self-networks in psychotic disorders

    NARCIS (Netherlands)

    Ebisch, Sjoerd J. H.; Aleman, Andre

    2016-01-01

    Self-disturbances are among the core features of schizophrenia and related psychotic disorders. The basic structure of the self could depend on the balance between intrinsic and extrinsic self-processing. We discuss studies on self-related processing in psychotic disorders that provide converging ev

  11. A family with extrinsic allergic alveolitis caused by wild city pigeons: A case report

    NARCIS (Netherlands)

    G.J. du Marchie Sarvaas; P.J.F.M. Merkus (Peter); J.C. de Jongste (Johan)

    2000-01-01

    textabstractWe describe a family in which the mother died of unresolved lung disease and whose 5 children, some of whom had previous signs of asthma, were subsequently affected by extrinsic allergic alveolitis caused by contact with wild city pigeon antigens. The children received

  12. Intrinsic and Extrinsic Motivation: Evaluating Benefits and Drawbacks from College Instructors' Perspectives

    Science.gov (United States)

    Lei, Simon A.

    2010-01-01

    A growing body of literature has been examined and discussed the effects of intrinsic and extrinsic motivation on student learning at the college level. Intrinsically motivated individuals have been able to develop high regards for learning various types of course information without the inclusion of external rewards or reinforcements. In…

  13. Extrinsic Tooth Enamel Color Changes and Their Relationship with the Quality of Water Consumed

    Directory of Open Access Journals (Sweden)

    Maria da Luz Rosário de Sousa

    2012-10-01

    Full Text Available The quality of the consumed drinking water may affect oral health. For example, the presence of iron in drinking water can cause aesthetic problems related to changes in dental enamel color. This study assessed the prevalence of extrinsic enamel color changes and their relationship with the quality of the water in the town of Caapiranga/AM-Brazil. Three hundred and forty six residents of the urban area were examined, and they also answered a questionnaire on eating habits and self-perceived oral health. As the initial results indicated an insufficient number of observations for the application of variance analysis (one-way ANOVA, the Student t test was chosen to compare levels of iron content in the water coming from two sources. The change in tooth color had a prevalence of 5.78% (20 people. The majority of the population (n = 261, 75.43% consumed well water. Those who presented extrinsic stains were uncomfortable with the appearance of their teeth (15.09%. We conclude that while there is excess of iron in the water in this region of Brazil, no association between extrinsic stains on the enamel and the level of iron in the water was found. There was a low prevalence of extrinsic stains in Caaparinga, being found only in children and adolescents. In the present study, an association between the presence of stains and the consumption of açai was determined, and those who presented them felt uncomfortable about their aesthetics.

  14. Creep of current-driven domain-wall lines: intrinsic versus extrinsic pinning

    NARCIS (Netherlands)

    Duine, R.A.; de Morais Smith, C.

    2008-01-01

    We present a model for current-driven motion of a magnetic domain-wall line, in which the dynamics of the domain wall is equivalent to that of an overdamped vortex line in an anisotropic pinning potential. This potential has both extrinsic contributions due to, e.g., sample inhomogeneities, and an

  15. Profiles of Intrinsic and Extrinsic Motivations in Elementary School: A Longitudinal Analysis

    Science.gov (United States)

    Corpus, Jennifer Henderlong; Wormington, Stephanie V.

    2014-01-01

    The authors used a person-centered, longitudinal approach to identify and evaluate naturally occurring combinations of intrinsic and extrinsic motivations among 490 third- through fifth-grade students. Cluster analysis revealed 3 groups, characterized by high levels of both motivations ("high quantity"): high intrinsic motivation but low…

  16. Students' Extrinsic and Intrinsic Motivation Level and Its Relationship with Their Mathematics Achievement

    Science.gov (United States)

    Acar Güvendir, Meltem

    2016-01-01

    This study focused on the extrinsic and intrinsic motivation levels of eighth grade students and its relationship with their mathematical achievement. The participants of the study included 6,829 students who took TIMSS in 2011 and 239 mathematics teachers. The data obtained from the student and teacher questionnaires that are included in the…

  17. Intrinsic Motivation, Extrinsic Motivation, and Academic Achievement among Indian Adolescents in Canada and India

    Science.gov (United States)

    Areepattamannil, Shaljan; Freeman, John G.; Klinger, Don A.

    2011-01-01

    The purpose of the present study was to examine the relationships among intrinsic motivation, extrinsic motivation, and academic achievement for the Indian immigrant adolescents in Canada in comparison to their counterparts in India. Descriptive discriminant analysis indicated that the Indian immigrant adolescents in Canada had higher intrinsic…

  18. Intrinsic and Extrinsic Reading Motivation as Predictors of Reading Literacy: A Longitudinal Study

    Science.gov (United States)

    Becker, Michael; McElvany, Nele; Kortenbruck, Marthe

    2010-01-01

    The purpose in this study was to examine the longitudinal relationships of intrinsic and extrinsic motivation with reading literacy development. In particular, the authors (a) investigated reading amount as mediator between motivation and reading literacy and (b) probed for bidirectional relationships between reading motivation and reading…

  19. Hypoxia in human colorectal adenocarcinoma: comparison between extrinsic and potential intrinsic hypoxia markers.

    NARCIS (Netherlands)

    Goethals, L.; Debucquoy, A.; Perneel, C.; Geboes, K.; Ectors, N.; Schutter, H. De; Penninckx, F.; McBride, W.H.; Begg, A.C.; Haustermans, K.

    2006-01-01

    PURPOSE: To detect and quantify hypoxia in colorectal adenocarcinomas by use of pimonidazole and iododeoxyuridine (IdUrd) as extrinsic markers and carbonic anhydrase IX (CA IX), microvessel density (MVD), epidermal growth-factor receptor (EGFR), and vascular endothelial growth factor (VEGF) as intri

  20. Extrinsic and intrinsic drivers of corporate social performance: evidence from foreign and domestic firms in Mexico

    NARCIS (Netherlands)

    Muller, A.; Kolk, A.

    2010-01-01

    The literature on corporate social performance (CSP) is largely split between approaches that consider CSP to be extrinsically driven and those that consider it to be intrinsically driven. While the management literature has paid attention to drivers of both types, the relationship between the two

  1. A family with extrinsic allergic alveolitis caused by wild city pigeons: A case report

    NARCIS (Netherlands)

    G.J. du Marchie Sarvaas; P.J.F.M. Merkus (Peter); J.C. de Jongste (Johan)

    2000-01-01

    textabstractWe describe a family in which the mother died of unresolved lung disease and whose 5 children, some of whom had previous signs of asthma, were subsequently affected by extrinsic allergic alveolitis caused by contact with wild city pigeon antigens. The children received

  2. Blowing in the (social) wind: implications of extrinsic esteem contingencies for terror management and health.

    Science.gov (United States)

    Arndt, Jamie; Cox, Cathy R; Goldenberg, Jamie L; Vess, Matthew; Routledge, Clay; Cooper, Douglas P; Cohen, Florette

    2009-06-01

    In 4 studies, the role of extrinsic esteem contingencies in adjusting to shifting health-relevant standards when managing existential fears was examined. Study 1 demonstrated that after reminders of death, higher dispositional focus on extrinsic self-esteem contingencies predicted greater interest in tanning. Using a more domain-specific approach, Study 2 showed that, after being reminded of death, the more individuals smoke for social esteem reasons, the more compelling they find an antismoking commercial that exposes adverse social consequences of smoking. Study 3 explored how situational factors (i.e., priming a contingent relational schema) that implicate extrinsic contingencies facilitated the impact of shifting standard primes on tanning intentions after mortality salience. Finally, Study 4 found that mortality salience led to increased endorsement of exercise as a basis of self-worth when participants who derive self-esteem from extrinsic sources visualized someone who exercises. Together, these studies demonstrate that reminders of death interact with prevalent social standards to influence everyday health decisions.

  3. The fragmented self: imbalance between intrinsic and extrinsic self-networks in psychotic disorders.

    Science.gov (United States)

    Ebisch, Sjoerd J H; Aleman, André

    2016-08-01

    Self-disturbances are among the core features of schizophrenia and related psychotic disorders. The basic structure of the self could depend on the balance between intrinsic and extrinsic self-processing. We discuss studies on self-related processing in psychotic disorders that provide converging evidence for disrupted communication between neural networks subserving the so-called intrinsic self and extrinsic self. This disruption might be mainly caused by impaired integrity of key brain hubs. The intrinsic self has been associated with cortical midline structures involved in self-referential processing, autobiographical memory, and emotional evaluation. Additionally, we highlight central aspects of the extrinsic self in its interaction with the environment using sensorimotor networks, including self-experience in sensation and actions. A deficient relationship between these self-aspects because of disrupted between-network interactions offers a framework to explain core clinical features of psychotic disorders. In particular, we show how relative isolation and reduced modularity of networks subserving intrinsic and extrinsic self-processing might trigger the emergence of hallucinations and delusions, and why patients with psychosis typically have difficulties with self-other relationships and do not recognise mental problems.

  4. Comparing Intrinsic and Extrinsic Evaluation of MT Output in a Dialogue System.

    NARCIS (Netherlands)

    van der Sluis, Ielka; Luz, S.; Schneider, A.

    2010-01-01

    We present an exploratory study to assess machine translation output for application in a dialogue system using an intrinsic and an extrinsic evaluation method. For the intrinsic evaluation we developed an annotation scheme to determine the quality of the translated utterances in isolation. For the

  5. A Novel Extrinsic Fiber-Optic Fabry-Perot Strain Sensor System Based on Optical Amplification

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A novel extrinsic fiber-optic Fabry-Perot interferometric strain sensor system is demonstrated based on the simultaneous use of the amplified spontaneous emission and optical amplification. The improvement of 3~4 orders of magnitude in signal level can be achieved.

  6. The efficacy of two prototype chewing gums for the removal of extrinsic tooth stain

    NARCIS (Netherlands)

    Ozcan, M; Kulak, Y; Kazazoglu, E

    2003-01-01

    Aim: To compare the potential efficacy of two prototype chewing gums in extrinsic stain removal on natural teeth. Setting: Dental school clinics. Design: Double-blind, two groups, parallel design. Participants: 76 adult volunteers (32m, 44f, mean age: 20.6 years old). Methods: Oral hard and soft tis

  7. Further Examining the American Dream: Differential Correlates of Intrinsic and Extrinsic Goals.

    Science.gov (United States)

    Kasser, Tim; Ryan, Richard M.

    1996-01-01

    In a sample of adult subjects (Study One), the relative importance and efficacy of extrinsic aspirations for financial success, an appealing appearance, and social recognition were associated with lower vitality and self-actualization and more physical symptoms. Study Two replicated these findings in a sample of college students. (JPS)

  8. Intrinsic and Extrinsic Factors That Influence Black Males to Attend Institutions of Higher Education

    Science.gov (United States)

    Etheridge, Robert

    2013-01-01

    The purpose of this qualitative, narrative study was to explore the intrinsic and extrinsic factors that motivated Black males to attend institutions of higher education. The Self-determination theory and the Integrated Model for Educational Choice formed the theoretical framework for this study. Eight Black males who were between the ages of 18…

  9. Indirect Correspondence-Based Robust Extrinsic Calibration of LiDAR and Camera.

    Science.gov (United States)

    Sim, Sungdae; Sock, Juil; Kwak, Kiho

    2016-06-22

    LiDAR and cameras have been broadly utilized in computer vision and autonomous vehicle applications. However, in order to convert data between the local coordinate systems, we must estimate the rigid body transformation between the sensors. In this paper, we propose a robust extrinsic calibration algorithm that can be implemented easily and has small calibration error. The extrinsic calibration parameters are estimated by minimizing the distance between corresponding features projected onto the image plane. The features are edge and centerline features on a v-shaped calibration target. The proposed algorithm contributes two ways to improve the calibration accuracy. First, we use different weights to distance between a point and a line feature according to the correspondence accuracy of the features. Second, we apply a penalizing function to exclude the influence of outliers in the calibration datasets. Additionally, based on our robust calibration approach for a single LiDAR-camera pair, we introduce a joint calibration that estimates the extrinsic parameters of multiple sensors at once by minimizing one objective function with loop closing constraints. We conduct several experiments to evaluate the performance of our extrinsic calibration algorithm. The experimental results show that our calibration method has better performance than the other approaches.

  10. Intrinsic and Extrinsic Reading Motivation as Predictors of Reading Literacy: A Longitudinal Study

    Science.gov (United States)

    Becker, Michael; McElvany, Nele; Kortenbruck, Marthe

    2010-01-01

    The purpose in this study was to examine the longitudinal relationships of intrinsic and extrinsic motivation with reading literacy development. In particular, the authors (a) investigated reading amount as mediator between motivation and reading literacy and (b) probed for bidirectional relationships between reading motivation and reading…

  11. Profiles of Intrinsic and Extrinsic Motivations in Elementary School: A Longitudinal Analysis

    Science.gov (United States)

    Corpus, Jennifer Henderlong; Wormington, Stephanie V.

    2014-01-01

    The authors used a person-centered, longitudinal approach to identify and evaluate naturally occurring combinations of intrinsic and extrinsic motivations among 490 third- through fifth-grade students. Cluster analysis revealed 3 groups, characterized by high levels of both motivations ("high quantity"): high intrinsic motivation but low…

  12. The dark side of monetary incentive: how does extrinsic reward crowd out intrinsic motivation.

    Science.gov (United States)

    Ma, Qingguo; Jin, Jia; Meng, Liang; Shen, Qiang

    2014-02-12

    It was widely believed that incentives could effectively enhance the motivation of both students and employees. However, psychologists reported that extrinsic reward actually could undermine individuals' intrinsic motivation to a given interesting task, which challenged viewpoints from traditional incentive theories. Numerous studies have been carried out to test and explain the undermining effect; however, the neural basis of this effect is still elusive. Here, we carried out an electrophysiological study with a simple but interesting stopwatch task to explore to what extent the performance-based monetary reward undermines individuals' intrinsic motivation toward the task. The electrophysiological data showed that the differentiated feedback-related negativity amplitude toward intrinsic success failure divergence was prominently reduced once the extrinsic reward was imposed beforehand. However, such a difference was not observed in the control group, in which no extrinsic reward was provided throughout the experiment. Furthermore, such a pattern was not observed for P300 amplitude. Therefore, the current results indicate that extrinsic reward demotivates the intrinsic response of individuals toward success-failure outcome, which was reflected in the corresponding reduced motivational-related differentiated feedback-related negativity, but not in amplitude of P300.

  13. Intrinsic Motivation, Extrinsic Motivation, and Academic Achievement among Indian Adolescents in Canada and India

    Science.gov (United States)

    Areepattamannil, Shaljan; Freeman, John G.; Klinger, Don A.

    2011-01-01

    The purpose of the present study was to examine the relationships among intrinsic motivation, extrinsic motivation, and academic achievement for the Indian immigrant adolescents in Canada in comparison to their counterparts in India. Descriptive discriminant analysis indicated that the Indian immigrant adolescents in Canada had higher intrinsic…

  14. Students' Extrinsic and Intrinsic Motivation Level and Its Relationship with Their Mathematics Achievement

    Science.gov (United States)

    Acar Güvendir, Meltem

    2016-01-01

    This study focused on the extrinsic and intrinsic motivation levels of eighth grade students and its relationship with their mathematical achievement. The participants of the study included 6,829 students who took TIMSS in 2011 and 239 mathematics teachers. The data obtained from the student and teacher questionnaires that are included in the…

  15. Promoting Intrinsic and Extrinsic Motivation among Chemistry Students Using Computer-Assisted Instruction

    Science.gov (United States)

    Gambari, Isiaka A.; Gbodi, Bimpe E.; Olakanmi, Eyitao U.; Abalaka, Eneojo N.

    2016-01-01

    The role of computer-assisted instruction in promoting intrinsic and extrinsic motivation among Nigerian secondary school chemistry students was investigated in this study. The study employed two modes of computer-assisted instruction (computer simulation instruction and computer tutorial instructional packages) and two levels of gender (male and…

  16. Intrinsic and Extrinsic Motivation: Evaluating Benefits and Drawbacks from College Instructors' Perspectives

    Science.gov (United States)

    Lei, Simon A.

    2010-01-01

    A growing body of literature has been examined and discussed the effects of intrinsic and extrinsic motivation on student learning at the college level. Intrinsically motivated individuals have been able to develop high regards for learning various types of course information without the inclusion of external rewards or reinforcements. In…

  17. Effects of Success/Failure and Extrinsic Rewards on Intrinsic Motivation Using a Competitive Motor Task.

    Science.gov (United States)

    McCaughan, Lindsay R.; McKinlay, Sue

    1981-01-01

    Female high school students participated in a motor task to assess the effects of success/failure feedback and extrinsic rewards on intrinsic motivation. It was found that a significant change in intrinsic motivation was due to the effects of success/failure feedback, but not to the effect of a tangible reward. (Authors/FG)

  18. Interactive Impact of Intrinsic Motivators and Extrinsic Rewards on Behavior and Motivation Outcomes

    Science.gov (United States)

    Xiang, Ping; Bruene, April; Chen, Ang

    2005-01-01

    In this study we examined the interrelationship among extrinsic rewards and achievement goals (including a work-avoidance goal), competence beliefs, and task values associated with health-enhancing running tasks over a school year. A group of elementary school students (n = 119) from a program that promoted running for running's sake and another…

  19. Interactive Impact of Intrinsic Motivators and Extrinsic Rewards on Behavior and Motivation Outcomes

    Science.gov (United States)

    Xiang, Ping; Bruene, April; Chen, Ang

    2005-01-01

    In this study we examined the interrelationship among extrinsic rewards and achievement goals (including a work-avoidance goal), competence beliefs, and task values associated with health-enhancing running tasks over a school year. A group of elementary school students (n = 119) from a program that promoted running for running's sake and another…

  20. Teacher Rewards: Going beyond the Stickers--Moving beyond Extrinsic Motivation

    Science.gov (United States)

    Taylor, Cheryl; McNaney-Funk, Claire; Jardine, Don; Lehman, Geannette; Fok-Chan, Evelyn

    2014-01-01

    Studies have shown that teachers appreciate intrinsic rewards, such as student achievement, positive relationships with students, self-growth, and mastery of professional skills, far greater than extrinsic motivators, like holidays and salary (Plihal, 1981; Plihal, 1982; Ashiedu & Scott-Ladd, 2012; Baleghizadeh & Gordani, 2012). This paper…

  1. Increasing Elementary and High School Student Motivation through the Use of Extrinsic and Intrinsic Rewards

    Science.gov (United States)

    Haywood, Joey; Kuespert, Sarah; Madecky, Dani; Nor, Abbey

    2008-01-01

    This action research project report examined strategies to motivate students from extrinsically rewarding behaviors to intrinsically motivating behaviors. The action research was conducted in two different schools by four different teacher researchers within the same district. Three teachers in an elementary building (Site A) and one teacher in a…

  2. The role of extrinsic rewards and cue-intention association in prospective memory in young children

    NARCIS (Netherlands)

    Sheppard, D.P.; Kretschmer, A.; Knispel, E.; Vollert, B.; Altgassen, A.M.

    2015-01-01

    The current study examined, for the first time, the effect of cue-intention association, as well as the effects of promised extrinsic rewards, on prospective memory in young children, aged 5-years-old (n = 39) and 7-years-old (n = 40). Children were asked to name pictures for a toy mole, whilst also

  3. Effects of Success/Failure and Extrinsic Rewards on Intrinsic Motivation Using a Competitive Motor Task.

    Science.gov (United States)

    McCaughan, Lindsay R.; McKinlay, Sue

    1981-01-01

    Female high school students participated in a motor task to assess the effects of success/failure feedback and extrinsic rewards on intrinsic motivation. It was found that a significant change in intrinsic motivation was due to the effects of success/failure feedback, but not to the effect of a tangible reward. (Authors/FG)

  4. Intrinsic Motivation and Extrinsic Rewards: A Commentary on Cameron and Pierce's Meta-Analysis.

    Science.gov (United States)

    Lepper, Mark R.; And Others

    1996-01-01

    Provides a critical analysis of the meta-analysis of J. Cameron and W. D. Pierce (1994) of the experimental literature on the effects of extrinsic rewards on intrinsic motivation. Their overly simplistic conclusion has little theoretical or practical value and results from misuse of meta-analytic procedures. (SLD)

  5. Tangible and Intangible Rewards and Employee Creativity: The Mediating Role of Situational Extrinsic Motivation

    Science.gov (United States)

    Yoon, Hye Jung; Sung, Sun Young; Choi, Jin Nam; Lee, Kyungmook; Kim, Seongsu

    2015-01-01

    This study examined the effects of tangible and intangible forms of creativity-contingent rewards on employee creativity. Situation-specific intrinsic and extrinsic motivations were proposed as mediators of the reward-creativity link. Based on data collected from 271 employees and their supervisors, results revealed the following: (a) intangible…

  6. The fragmented self : imbalance between intrinsic and extrinsic self-networks in psychotic disorders

    NARCIS (Netherlands)

    Ebisch, Sjoerd J. H.; Aleman, Andre

    2016-01-01

    Self-disturbances are among the core features of schizophrenia and related psychotic disorders. The basic structure of the self could depend on the balance between intrinsic and extrinsic self-processing. We discuss studies on self-related processing in psychotic disorders that provide converging ev

  7. Flavor Profile of Chinese Liquor Is Altered by Interactions of Intrinsic and Extrinsic Microbes.

    Science.gov (United States)

    Wu, Qun; Kong, Yu; Xu, Yan

    2015-10-16

    The flavor profile of Chinese liquor is the result of the metabolic activity of its microbial community. Given the importance of the microbial interaction, a novel way to control the liquor's flavor is by regulating the composition of the community. In this study, we efficiently improved the liquor's flavor by perturbing the intrinsic microbial metabolism with extrinsic microbes. We first constructed a basic microbial group (intrinsic) containing Saccharomyces cerevisiae, Wickerhamomyces anomalus, and Issatchenkia orientalis and added special flavor producers (extrinsic), Saccharomyces uvarum and Saccharomyces servazzii, to this intrinsic group. Upon the addition of the extrinsic microbes, the maximum specific growth rates of S. cerevisiae and I. orientalis increased from 6.19 to 43.28/day and from 1.15 to 14.32/day, respectively, but that of W. anomalus changed from 1.00 to 0.96/day. In addition, most volatile compounds known to be produced by the extrinsic strains were not produced. However, more esters, alcohols, and acids were produced by S. cerevisiae and I. orientalis. Six compounds were significantly different by random forest analysis after perturbation. Among them, increases in ethyl hexanoate, isobutanol, and 3-methylbutyric acid were correlated with S. cerevisiae and I. orientalis, and a decrease in geranyl acetone was correlated with W. anomalus. Variations in ethyl acetate and 2-phenylethanol might be due to the varied activity of W. anomalus and S. cerevisiae. This work showed the effect of the interaction between the intrinsic and extrinsic microbes on liquor flavor, which would be beneficial for improving the quality of Chinese liquor. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  8. Force-independent distribution of correlated neural inputs to hand muscles during three-digit grasping.

    Science.gov (United States)

    Poston, Brach; Danna-Dos Santos, Alessander; Jesunathadas, Mark; Hamm, Thomas M; Santello, Marco

    2010-08-01

    The ability to modulate digit forces during grasping relies on the coordination of multiple hand muscles. Because many muscles innervate each digit, the CNS can potentially choose from a large number of muscle coordination patterns to generate a given digit force. Studies of single-digit force production tasks have revealed that the electromyographic (EMG) activity scales uniformly across all muscles as a function of digit force. However, the extent to which this finding applies to the coordination of forces across multiple digits is unknown. We addressed this question by asking subjects (n = 8) to exert isometric forces using a three-digit grip (thumb, index, and middle fingers) that allowed for the quantification of hand muscle coordination within and across digits as a function of grasp force (5, 20, 40, 60, and 80% maximal voluntary force). We recorded EMG from 12 muscles (6 extrinsic and 6 intrinsic) of the three digits. Hand muscle coordination patterns were quantified in the amplitude and frequency domains (EMG-EMG coherence). EMG amplitude scaled uniformly across all hand muscles as a function of grasp force (muscle x force interaction: P = 0.997; cosines of angle between muscle activation pattern vector pairs: 0.897-0.997). Similarly, EMG-EMG coherence was not significantly affected by force (P = 0.324). However, coherence was stronger across extrinsic than that across intrinsic muscle pairs (P = 0.0039). These findings indicate that the distribution of neural drive to multiple hand muscles is force independent and may reflect the anatomical properties or functional roles of hand muscle groups.

  9. Ossification Pattern of Estuarine Dolphin (Sotalia guianensis) Forelimbs, from the Coast of the State of Espírito Santo, Brazil.

    Science.gov (United States)

    de Carvalho, Anna Paula Martins; Lima, Juliana Ywasaki; Azevedo, Carolina Torres; Botta, Silvina; de Queiroz, Fábio Ferreira; Campos, Adélia Sepúlveda; Barbosa, Lupércio de Araújo; da Silveira, Leonardo Serafim

    2015-01-01

    The estuarine dolphin, Sotalia guianensis, is one of the most abundant cetacean species in Brazil. Determination of age and of aspects associated with the development of this species is significant new studies. Counts of growth layer groups in dentin are used to estimate age of these animals, though other ways to evaluate development are also adopted, like the measurement of total length (TL). This study presents a procedure to evaluate the development of the estuarine dolphin based on the ossification pattern of forelimbs. Thirty-seven estuarine dolphins found in the state of Espírito Santo, Brazil, were examined. Age was estimated, TL was measured and ossification of epiphyses was examined by radiography. We analyzed results using the Spearman correlation. Inspection of radiographs allowed evaluation of the significance of the correlation between age and development of the proximal (r = 0.9109) and distal (r = 0.9092) radial epiphyses, and of the distal ulnar epiphyses (r = 0.9055). Radiographic analysis of forelimbs proved to be an appropriate method to evaluate physical maturity, and may be a helpful tool to estimate age of these animals in ecological and population studies.

  10. Dexterity: A MATLAB-based analysis software suite for processing and visualizing data from tasks that measure arm or forelimb function.

    Science.gov (United States)

    Butensky, Samuel D; Sloan, Andrew P; Meyers, Eric; Carmel, Jason B

    2017-07-15

    Hand function is critical for independence, and neurological injury often impairs dexterity. To measure hand function in people or forelimb function in animals, sensors are employed to quantify manipulation. These sensors make assessment easier and more quantitative and allow automation of these tasks. While automated tasks improve objectivity and throughput, they also produce large amounts of data that can be burdensome to analyze. We created software called Dexterity that simplifies data analysis of automated reaching tasks. Dexterity is MATLAB software that enables quick analysis of data from forelimb tasks. Through a graphical user interface, files are loaded and data are identified and analyzed. These data can be annotated or graphed directly. Analysis is saved, and the graph and corresponding data can be exported. For additional analysis, Dexterity provides access to custom scripts created by other users. To determine the utility of Dexterity, we performed a study to evaluate the effects of task difficulty on the degree of impairment after injury. Dexterity analyzed two months of data and allowed new users to annotate the experiment, visualize results, and save and export data easily. Previous analysis of tasks was performed with custom data analysis, requiring expertise with analysis software. Dexterity made the tools required to analyze, visualize and annotate data easy to use by investigators without data science experience. Dexterity increases accessibility to automated tasks that measure dexterity by making analysis of large data intuitive, robust, and efficient. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Muscle pain

    African Journals Online (AJOL)

    Causes of muscle pain include stress, physical activity, infections, hyper or .... Acupuncture. It is a traditional Chinese-based therapeutic method which ..... and Spinal Mechanisms of Pain and Dry Needling Mediated Analgesia: A Clinical.

  12. Transcriptional networks that regulate muscle stem cell function.

    Science.gov (United States)

    Punch, Vincent G; Jones, Andrew E; Rudnicki, Michael A

    2009-01-01

    Muscle stem cells comprise different populations of stem and progenitor cells found in embryonic and adult tissues. A number of signaling and transcriptional networks are responsible for specification and survival of these cell populations and regulation of their behavior during growth and regeneration. Muscle progenitor cells are mostly derived from the somites of developing embryos, while satellite cells are the progenitor cells responsible for the majority of postnatal growth and adult muscle regeneration. In resting muscle, these stem cells are quiescent, but reenter the cell cycle during their activation, whereby they undergo decisions to self-renew, proliferate, or differentiate and fuse into multinucleated myofibers to repair damaged muscle. Regulation of muscle stem cell activity is under the precise control of a number of extrinsic signaling pathways and active transcriptional networks that dictate their behavior, fate, and regenerative potential. Here, we review the networks responsible for these different aspects of muscle stem cell biology and discuss prevalent parallels between mechanisms regulating the activity of embryonic muscle progenitor cells and adult satellite cells.

  13. Raising trophy kids: The role of mothers' contingent self-esteem in maternal promotion of extrinsic goals.

    Science.gov (United States)

    Soenens, Bart; Wuyts, Dorien; Vansteenkiste, Maarten; Mageau, Geneviève A; Brenning, Katrijn

    2015-07-01

    This study examined the role of mothers' child-invested contingent self-esteem, that is, their tendency to hinge their self-worth on their child's achievements, in maternal promotion of extrinsic goals, as perceived by adolescents. It was also examined whether maternal promotion of extrinsic goals would, in turn, relate to adolescents' Social Dominance Orientation (SDO). Participants were 184 mothers and their adolescent children (66% female). Maternal child-invested contingent self-esteem predicted adolescent-perceived maternal promotion of extrinsic goals, even when taking into account the variance shared between the promotion of extrinsic goals and mothers' use of a controlling parenting style. Maternal child-invested contingent self-esteem also moderated associations between mothers' personal pursuit of extrinsic goals and their promotion of those goals, such that the association between mothers' own extrinsic goals and their promotion of those goals was significant only among mothers high on child-invested contingent self-esteem. Maternal promotion of extrinsic goals was, in turn, related to adolescent SDO, suggesting that the dynamics examined in this study ultimately relate to adolescents' social and ideological development. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  14. 海龟柔性前肢仿生推进研究%Bionic Research on Turtle's Flexible Forelimb Propulsion

    Institute of Scientific and Technical Information of China (English)

    张铭钧; 刘晓白; 徐建安; 储定慧; 闫娜

    2011-01-01

    为探讨水翼法推进方式,进行了海龟柔性前肢仿生技术研究.基于水翼法运动解析,研究了海龟柔性水翼的弦向形变特征、反卡门涡街脱泻及斯特劳哈尔数等,推算出水翼尾涡脱泻的斯特劳哈尔数位于0.2~0.45之间,雷诺数位于3×102~3×104之间;根据海龟水翼粘弹本构特性,研制了半骼式仿生柔性水翼,并对其进行柔性形变和组织模态分析.通过水下仿生实验平台进行了半骼式柔性水翼和全骼式刚性水翼推进的直航、转艏性能对比实验,实验结果显示,虽然柔性水翼只有在较高ω1值拍动时的推进效率才高于刚性水翼,但其速度增长率却始终高于刚性水翼:并且随着ω1值的增长,柔性水翼对于样机速度减振方面的作用一直存在且越来越明显.实验研究结果为柔性水翼操纵与控制研究提供了技术基础.%In order to investigate the hydrofoil propulsion method, the bionic technology of the turtle's flexible forelimbs is studied. Based on the kinematical analysis of turtle hydrofoil, the chordwise deformation characteristics, the reverse Kurman vortex street shedding, and the Strouhal number of flexible hydrofoil are studied, and then it is calculated that the Strouhal number is between 0.2 and 0.45, the Reynolds number is from 3× 102 to 3× 104. According to the viscoelastic constitutive property of turtle hydrofoil, the half-iliac bionic flexible hydrofoil is developed, and its flexible deformation as well as tissue mode are analyzed. By use of the underwater bionic experimental sample, the direct navigation and yawing performance contrast tests of bionic sample with the half-iliac flexible hydrofoil and whole-iliac rigid hydrofoil are conducted respectively.The experiments' results show that, however the propulsion efficiency of flexible hydrofoil is higher than the rigid one only moving at the high value of ω1, the sample's acceleration when propelled by the flexible hydrofoil

  15. Finger muscle attachments for an OpenSim upper-extremity model.

    Directory of Open Access Journals (Sweden)

    Jong Hwa Lee

    Full Text Available We determined muscle attachment points for the index, middle, ring and little fingers in an OpenSim upper-extremity model. Attachment points were selected to match both experimentally measured locations and mechanical function (moment arms. Although experimental measurements of finger muscle attachments have been made, models differ from specimens in many respects such as bone segment ratio, joint kinematics and coordinate system. Likewise, moment arms are not available for all intrinsic finger muscles. Therefore, it was necessary to scale and translate muscle attachments from one experimental or model environment to another while preserving mechanical function. We used a two-step process. First, we estimated muscle function by calculating moment arms for all intrinsic and extrinsic muscles using the partial velocity method. Second, optimization using Simulated Annealing and Hooke-Jeeves algorithms found muscle-tendon paths that minimized root mean square (RMS differences between experimental and modeled moment arms. The partial velocity method resulted in variance accounted for (VAF between measured and calculated moment arms of 75.5% on average (range from 48.5% to 99.5% for intrinsic and extrinsic index finger muscles where measured data were available. RMS error between experimental and optimized values was within one standard deviation (S.D of measured moment arm (mean RMS error = 1.5 mm < measured S.D = 2.5 mm. Validation of both steps of the technique allowed for estimation of muscle attachment points for muscles whose moment arms have not been measured. Differences between modeled and experimentally measured muscle attachments, averaged over all finger joints, were less than 4.9 mm (within 7.1% of the average length of the muscle-tendon paths. The resulting non-proprietary musculoskeletal model of the human fingers could be useful for many applications, including better understanding of complex multi-touch and gestural movements.

  16. Mechanisms of skeletal muscle aging: insights from Drosophila and mammalian models

    Directory of Open Access Journals (Sweden)

    Fabio Demontis

    2013-11-01

    Full Text Available A characteristic feature of aged humans and other mammals is the debilitating, progressive loss of skeletal muscle function and mass that is known as sarcopenia. Age-related muscle dysfunction occurs to an even greater extent during the relatively short lifespan of the fruit fly Drosophila melanogaster. Studies in model organisms indicate that sarcopenia is driven by a combination of muscle tissue extrinsic and intrinsic factors, and that it fundamentally differs from the rapid atrophy of muscles observed following disuse and fasting. Extrinsic changes in innervation, stem cell function and endocrine regulation of muscle homeostasis contribute to muscle aging. In addition, organelle dysfunction and compromised protein homeostasis are among the primary intrinsic causes. Some of these age-related changes can in turn contribute to the induction of compensatory stress responses that have a protective role during muscle aging. In this Review, we outline how studies in Drosophila and mammalian model organisms can each provide distinct advantages to facilitate the understanding of this complex multifactorial condition and how they can be used to identify suitable therapies.

  17. Agent-based computational model investigates muscle-specific responses to disuse-induced atrophy

    Science.gov (United States)

    Martin, Kyle S.; Peirce, Shayn M.

    2015-01-01

    Skeletal muscle is highly responsive to use. In particular, muscle atrophy attributable to decreased activity is a common problem among the elderly and injured/immobile. However, each muscle does not respond the same way. We developed an agent-based model that generates a tissue-level skeletal muscle response to disuse/immobilization. The model incorporates tissue-specific muscle fiber architecture parameters and simulates changes in muscle fiber size as a result of disuse-induced atrophy that are consistent with published experiments. We created simulations of 49 forelimb and hindlimb muscles of the rat by incorporating eight fiber-type and size parameters to explore how these parameters, which vary widely across muscles, influence sensitivity to disuse-induced atrophy. Of the 49 muscles modeled, the soleus exhibited the greatest atrophy after 14 days of simulated immobilization (51% decrease in fiber size), whereas the extensor digitorum communis atrophied the least (32%). Analysis of these simulations revealed that both fiber-type distribution and fiber-size distribution influence the sensitivity to disuse atrophy even though no single tissue architecture parameter correlated with atrophy rate. Additionally, software agents representing fibroblasts were incorporated into the model to investigate cellular interactions during atrophy. Sensitivity analyses revealed that fibroblast agents have the potential to affect disuse-induced atrophy, albeit with a lesser effect than fiber type and size. In particular, muscle atrophy elevated slightly with increased initial fibroblast population and increased production of TNF-α. Overall, the agent-based model provides a novel framework for investigating both tissue adaptations and cellular interactions in skeletal muscle during atrophy. PMID:25722379

  18. Progressive Muscle Atrophy and Weakness After Treatment by Mantle Field Radiotherapy in Hodgkin Lymphoma Survivors

    Energy Technology Data Exchange (ETDEWEB)

    Leeuwen-Segarceanu, Elena M. van, E-mail: e.segarceanu@antoniusziekenhuis.nl [Department of Internal Medicine, St. Antonius Hospital, Nieuwegein (Netherlands); Dorresteijn, Lucille D.A. [Department of Neurology, Medisch Spectrum Twente, Enschede (Netherlands); Pillen, Sigrid [Department of Neurology and Clinical Neurophysiology, Donders Center for Neuroscience, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands); Biesma, Douwe H. [Department of Internal Medicine, University Medical Center Utrecht (Netherlands); Vogels, Oscar J.M. [Department of Neurology and Clinical Neurophysiology, St. Antonius Hospital, Nieuwegein (Netherlands); Alfen, Nens van [Department of Neurology and Clinical Neurophysiology, Donders Center for Neuroscience, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands)

    2012-02-01

    Purpose: To describe the damage to the muscles and propose a pathophysiologic mechanism for muscle atrophy and weakness after mantle field radiotherapy in Hodgkin lymphoma (HL) survivors. Methods and Materials: We examined 12 patients treated by mantle field radiotherapy between 1969 and 1998. Besides evaluation of their symptoms, the following tests were performed: dynamometry; ultrasound of the sternocleidomastoid, biceps, and antebrachial flexor muscles; and needle electromyography of the neck, deltoid, and ultrasonographically affected arm muscles. Results: Ten patients (83%) experienced neck complaints, mostly pain and muscle weakness. On clinical examination, neck flexors were more often affected than neck extensors. On ultrasound, the sternocleidomastoid was severely atrophic in 8 patients, but abnormal echo intensity was seen in only 3 patients. Electromyography of the neck muscles showed mostly myogenic changes, whereas the deltoid, biceps, and antebrachial flexor muscles seemed to have mostly neurogenic damage. Conclusions: Many patients previously treated by mantle field radiotherapy develop severe atrophy and weakness of the neck muscles. Neck muscles within the radiation field show mostly myogenic damage, and muscles outside the mantle field show mostly neurogenic damage. The discrepancy between echo intensity and atrophy suggests that muscle damage is most likely caused by an extrinsic factor such as progressive microvascular fibrosis. This is also presumed to cause damage to nerves within the radiated field, resulting in neurogenic damage of the deltoid and arm muscles.

  19. Progressive muscle atrophy and weakness after treatment by mantle field radiotherapy in Hodgkin lymphoma survivors.

    Science.gov (United States)

    van Leeuwen-Segarceanu, Elena M; Dorresteijn, Lucille D A; Pillen, Sigrid; Biesma, Douwe H; Vogels, Oscar J M; van Alfen, Nens

    2012-02-01

    To describe the damage to the muscles and propose a pathophysiologic mechanism for muscle atrophy and weakness after mantle field radiotherapy in Hodgkin lymphoma (HL) survivors. We examined 12 patients treated by mantle field radiotherapy between 1969 and 1998. Besides evaluation of their symptoms, the following tests were performed: dynamometry; ultrasound of the sternocleidomastoid, biceps, and antebrachial flexor muscles; and needle electromyography of the neck, deltoid, and ultrasonographically affected arm muscles. Ten patients (83%) experienced neck complaints, mostly pain and muscle weakness. On clinical examination, neck flexors were more often affected than neck extensors. On ultrasound, the sternocleidomastoid was severely atrophic in 8 patients, but abnormal echo intensity was seen in only 3 patients. Electromyography of the neck muscles showed mostly myogenic changes, whereas the deltoid, biceps, and antebrachial flexor muscles seemed to have mostly neurogenic damage. Many patients previously treated by mantle field radiotherapy develop severe atrophy and weakness of the neck muscles. Neck muscles within the radiation field show mostly myogenic damage, and muscles outside the mantle field show mostly neurogenic damage. The discrepancy between echo intensity and atrophy suggests that muscle damage is most likely caused by an extrinsic factor such as progressive microvascular fibrosis. This is also presumed to cause damage to nerves within the radiated field, resulting in neurogenic damage of the deltoid and arm muscles. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. A Novel Iterative Receiver Based on Extrinsic Information Update for MIMO Systems

    Institute of Scientific and Technical Information of China (English)

    LIN Wen-feng; HE Chen

    2007-01-01

    A novel iterative receiver for multiple input multiple output (MIMO) systems was introduced.Its basis concept is that the reliability of extrinsic information will be strengthened with continuous iterations.Extrinsic information of present iteration is added with prior information of last iteration to obtain performance gain.The simulation results show that the improved iterative receiver can approach the 5th iteration performance of conventional soft interference cancellation (SIC)-minimum mean square error (MMSE) iterative receiver after the 2nd iteration with less computational complexity.Compared with conventional iterative receiver, the improved iterative receiver has 1dB performance gain at bit error rate (BER) of 10-5, with four transmit antennas and four receive antennas system.

  1. Internal thermal origin mechanism of Karstic collapse column with no smoothly extrinsic cycle

    Institute of Scientific and Technical Information of China (English)

    LI Yong-jun; PENG Su-ping; LI Pei-quan; LIU Deng-xian; LIAN Hui-qing

    2008-01-01

    Huainan coal field as main object, investigation of Karstic hydrogeological conditions were developed in Huainan structureal unit, and the basic conditions, features and rules of Karstic growth were summarized. Geology background and causes of Karstic collapse columns were analyzed. Combined with ancient physiognomy, environment and litho-facies features. After studying synthetically Karstic collapse columns, shape of collapse body, filling feature, hydrodynamic condition and agglutinate material in Huainan area, considering mine hydrogeological conditions of Xuhuai coal field and referenced Karstic collapse columns characters of other mines in North China, the internal thermal origin theory is elementarily formed for Karstic collapse columns extrinsic cycle can not operate smoothly. Finaly, three aspects including distributing features of different kinds of Karstic collapse columns in north China type coal field, conditions of Karstic collapse columns origined from internal thermal with no smoothly extrinsic cycle, mechanics of causes were analyzed and demonstrated.

  2. Resolution limits of extrinsic Fabry-Perot interferometric displacement sensors utilizing wavelength scanning interrogation.

    Science.gov (United States)

    Ushakov, Nikolai; Liokumovich, Leonid

    2014-08-10

    The factors limiting the resolution of displacement sensors based on the extrinsic Fabry-Perot interferometer were studied. An analytical model giving the dependency of extrinsic Fabry-Perot interferometric (EFPI) resolution on the parameters of an optical setup and a sensor interrogator was developed. The proposed model enables one to either estimate the limit of possible resolution achievable with a given setup, or derive the requirements for optical elements and/or a sensor interrogator necessary for attaining the desired sensor resolution. An experiment supporting the analytical derivations was performed, demonstrating a large dynamic measurement range (with cavity length from tens of microns to 5 mm), a high baseline resolution (from 14 pm), and good agreement with the model.

  3. The inspiratory "squawk" in extrinsic allergic alveolitis and other pulmonary fibroses.

    Science.gov (United States)

    Earis, J E; Marsh, K; Pearson, M G; Ogilvie, C M

    1982-01-01

    An inspiratory musical sound ("squawk") was recorded in 14 patients with diffuse pulmonary fibrosis. These were divided into two groups: nine patients suffering from extrinsic allergic alveolitis (seven with bird fancier's lung and two with farmer's lung) and five patients with pulmonary fibrosis due to other causes, including rheumatoid disease, Wegener's granulomatosis, systemic sclerosis, and sarcoidosis. Clinical studies and phonopneumographic analysis of 10 consecutive squawks in each patient showed that the sound in the group with extrinsic allergic alveolitis was of shorter duration, occurred later in inspiration, and tended to be of higher frequency than the sound heard in the other group. Inspiratory crackles were present in all patients and in eight a single loud crackle preceded the squawk. We suggest that squawks, like crackles, result from the opening of airways and that the differences between the squawks in the two groups may reflect the size of the affected airways. PMID:7170682

  4. Estimating consumer preferences for extrinsic and intrinsic attributes of vegetables. A study of German consumers

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez-Guerrero, J. F.; Gazquez-Abad, J. C.; Huertas-Garcia, R.; Mondejar-Jimenez, J. A.

    2012-11-01

    Preference formation developed during the consumers evaluation of alternatives is one of the most important stages in models of consumer purchasing behaviour. This is especially true for the purchase of vegetables. The purpose of this paper is to analyze the role of extrinsic versus intrinsic attributes in the behaviour of consumer when purchasing cucumbers, considering four attributes; price, country of origin and production method (extrinsic), and freshness (intrinsic). Utilizing a sample of German tourists visiting the city of Almeria (Spain), conjoint analysis methodology is used. The results suggest that an intrinsic aspect (freshness) is the most important attribute for consumers. Therefore, marketers are advised to consider the importance of this attribute to the consumer and try to position the product in the destination markets on the basis of product freshness. (Author) 91 refs.

  5. Prelamin A causes progeria through cell-extrinsic mechanisms and prevents cancer invasion

    Science.gov (United States)

    de la Rosa, Jorge; Freije, José M. P.; Cabanillas, Rubén; Osorio, Fernando G.; Fraga, Mario F.; Fernández-García, M. Soledad; Rad, Roland; Fanjul, Víctor; Ugalde, Alejandro P.; Liang, Qi; Prosser, Haydn M.; Bradley, Allan; Cadiñanos, Juan; López-Otín, Carlos

    2013-01-01

    Defining the relationship between ageing and cancer is a crucial but challenging task. Mice deficient in Zmpste24, a metalloproteinase mutated in human progeria and involved in nuclear prelamin A maturation, recapitulate multiple features of ageing. However, their short lifespan and serious cell-intrinsic and cell-extrinsic alterations restrict the application and interpretation of carcinogenesis protocols. Here we present Zmpste24 mosaic mice that lack these limitations. Zmpste24 mosaic mice develop normally and keep similar proportions of Zmpste24-deficient (prelamin A accumulating) and Zmpste24-proficient (mature lamin A containing) cells throughout life, revealing that cell-extrinsic mechanisms are preeminent for progeria development. Moreover, prelamin A accumulation does not impair tumour initiation and growth, but it decreases the incidence of infiltrating oral carcinomas. Accordingly, silencing of ZMPSTE24 reduces human cancer cell invasiveness. Our results support the potential of cell-based and systemic therapies for progeria and highlight ZMPSTE24 as a new anticancer target. PMID:23917225

  6. Prelamin A causes progeria through cell-extrinsic mechanisms and prevents cancer invasion.

    Science.gov (United States)

    de la Rosa, Jorge; Freije, José M P; Cabanillas, Rubén; Osorio, Fernando G; Fraga, Mario F; Fernández-García, M Soledad; Rad, Roland; Fanjul, Víctor; Ugalde, Alejandro P; Liang, Qi; Prosser, Haydn M; Bradley, Allan; Cadiñanos, Juan; López-Otín, Carlos

    2013-01-01

    Defining the relationship between ageing and cancer is a crucial but challenging task. Mice deficient in Zmpste24, a metalloproteinase mutated in human progeria and involved in nuclear prelamin A maturation, recapitulate multiple features of ageing. However, their short lifespan and serious cell-intrinsic and cell-extrinsic alterations restrict the application and interpretation of carcinogenesis protocols. Here we present Zmpste24 mosaic mice that lack these limitations. Zmpste24 mosaic mice develop normally and keep similar proportions of Zmpste24-deficient (prelamin A-accumulating) and Zmpste24-proficient (mature lamin A-containing) cells throughout life, revealing that cell-extrinsic mechanisms are preeminent for progeria development. Moreover, prelamin A accumulation does not impair tumour initiation and growth, but it decreases the incidence of infiltrating oral carcinomas. Accordingly, silencing of ZMPSTE24 reduces human cancer cell invasiveness. Our results support the potential of cell-based and systemic therapies for progeria and highlight ZMPSTE24 as a new anticancer target.

  7. Intrinsic and extrinsic motivation in early adolescents' friendship development: friendship selection, influence, and prospective friendship quality.

    Science.gov (United States)

    Ojanen, Tiina; Sijtsema, Jelle J; Hawley, Patricia H; Little, Todd D

    2010-12-01

    Friendships are essential for adolescent social development. However, they may be pursued for varying motives, which, in turn, may predict similarity in friendships via social selection or social influence processes, and likely help to explain friendship quality. We examined the effect of early adolescents' (N = 374, 12-14 years) intrinsic and extrinsic friendship motivation on friendship selection and social influence by utilizing social network modeling. In addition, longitudinal relations among motivation and friendship quality were estimated with structural equation modeling. Extrinsic motivation predicted activity in making friendship nominations during the sixth grade and lower friendship quality across time. Intrinsic motivation predicted inactivity in making friendship nominations during the sixth, popularity as a friend across the transition to middle school, and higher friendship quality across time. Social influence effects were observed for both motives, but were more pronounced for intrinsic motivation.

  8. Intrinsic motivation, extrinsic motivation, and learning English as a foreign language.

    Science.gov (United States)

    Shaikholeslami, Razieh; Khayyer, Mohammad

    2006-12-01

    The objective of this study was to examine the relationships of amotivation, extrinsic motivation, and intrinsic motivation with learning the English language. The 230 Iranian students at Shiraz University were tested using the Language Learning Orientations Scales to measure Amotivation, Extrinsic Motivation, and Intrinsic Motivation as explanatory variables. Grade point average in English exams was selected as a measure of English learning Achievement. Multiple regression analysis revealed that learning Achievement scores were predicted by scores on the Amotivation subscale, Introjected Regulation subscale, Knowledge subscale, and Stimulation subscale, whereas, the External and Identified Regulation and Accomplishment subscales did not have a significant relationship with Achievement. The results are discussed in terms of differences in Iranian context and culture.

  9. Extrinsic electromagnetic chirality in all-photodesigned one-dimensional THz metamaterials

    CERN Document Server

    Rizza, Carlo; Brambilla, Massimo; Prati, Franco; Ciattoni, Alessandro

    2016-01-01

    We suggest that all-photodesigned metamaterials, sub-wavelength custom patterns of photo-excited carriers on a semiconductor, can display an exotic extrinsic electromagnetic chirality in terahertz (THz) frequency range. We consider a photo-induced pattern exhibiting 1D geometrical chirality, i.e. its mirror image can not be superposed onto itself by translations without rotations and, in the long wavelength limit, we evaluate its bianisotropic response. The photo-induced extrinsic chirality turns out to be fully reconfigurable by recasting the optical illumination which supports the photo-excited carriers. The all-photodesigning technique represents a feasible, easy and powerful method for achieving effective matter functionalization and, combined with the chiral asymmetry, it could be the platform for a new generation of reconfigurable devices for THz wave polarization manipulation.

  10. The CNS stochastically selects motor plan utilizing extrinsic and intrinsic representations.

    Science.gov (United States)

    Kodl, Jindrich; Ganesh, Gowrishankar; Burdet, Etienne

    2011-01-01

    Traditionally motor studies have assumed that motor tasks are executed according to a single plan characterized by regular patterns, which corresponds to the minimum of a cost function in extrinsic or intrinsic coordinates. However, the novel via-point task examined in this paper shows distinct planning and execution stages in motion production and demonstrates that subjects randomly select from several available motor plans to perform a task. Examination of the effect of pre-training and via-point orientation on subject behavior reveals that the selection of a plan depends on previous movements and is affected by constraints both intrinsic and extrinsic of the body. These results provide new insights into the hierarchical structure of motion planning in humans, which can only be explained if the current models of motor control integrate an explicit plan selection stage.

  11. The CNS stochastically selects motor plan utilizing extrinsic and intrinsic representations.

    Directory of Open Access Journals (Sweden)

    Jindrich Kodl

    Full Text Available Traditionally motor studies have assumed that motor tasks are executed according to a single plan characterized by regular patterns, which corresponds to the minimum of a cost function in extrinsic or intrinsic coordinates. However, the novel via-point task examined in this paper shows distinct planning and execution stages in motion production and demonstrates that subjects randomly select from several available motor plans to perform a task. Examination of the effect of pre-training and via-point orientation on subject behavior reveals that the selection of a plan depends on previous movements and is affected by constraints both intrinsic and extrinsic of the body. These results provide new insights into the hierarchical structure of motion planning in humans, which can only be explained if the current models of motor control integrate an explicit plan selection stage.

  12. Multicamera system extrinsic stability analysis and large-span truss string structure displacement measurement.

    Science.gov (United States)

    Liu, Cong; Dong, Shuai; Mokhtar, Mohammed; He, Xiaoyuan; Lu, Jinyu; Wu, Xiaolong

    2016-10-10

    A novel technique for measuring the displacements of large-span truss string structures that employs multicamera systems is proposed. The coordinates of the stereo-vision systems are unified in a single global coordinate system by employing 3D data reconstructed using close-range photogrammetry. To estimate the camera's attitude motions during an experiment, an instantaneous extrinsic rectification algorithm was developed. Experiments in which a camera was rotated and translated were conducted to verify the accuracy and precision of the developed algorithm. In addition, the proposed multicamera systems were employed to analyze a large-span truss string structure. The displacement results obtained from numerical simulations and experiments using pre-calibration and rectification methods are compared in this paper, and the stability of the camera's extrinsic parameters is discussed.

  13. Examining the relationship between recreational sport participation and intrinsic and extrinsic motivation and amotivation.

    Science.gov (United States)

    Tsorbatzoudis, Haralambos; Alexandris, Konstantinos; Zahariadis, Panagiotis; Grouios, George

    2006-10-01

    This study aimed at investigating the effect of motivational dimensions proposed by Pelletier, et al. in 1995, both on sport participation levels and on intention for continuing participation among adult recreational sport participants. Two hundred and fifty-seven adult individuals, who reported participation in some type of sport and physical activity, completed the Sport Motivation Scale and a scale measuring intention. The study provided evidence to suggest that increased motivation leads to increased participation. Amotivation significantly decreased from the least to the most frequent participant groups, while both extrinsic and intrinsic motivation followed the reverse pattern. The results also indicated that increased intrinsic motivation to gain knowledge and accomplishment and extrinsic motivation (introjected regulation) are positively correlated with individuals' intentions to continue participation, while amotivation is negatively related. These results provide limited support for the self-determination theory. Implications for sport participation promotion are discussed.

  14. A curve fitting method for extrinsic camera calibration from a single image of a cylindrical object

    Science.gov (United States)

    Winkler, A. W.; Zagar, B. G.

    2013-08-01

    An important step in the process of optical steel coil quality assurance is to measure the proportions of width and radius of steel coils as well as the relative position and orientation of the camera. This work attempts to estimate these extrinsic parameters from single images by using the cylindrical coil itself as the calibration target. Therefore, an adaptive least-squares algorithm is applied to fit parametrized curves to the detected true coil outline in the acquisition. The employed model allows for strictly separating the intrinsic and the extrinsic parameters. Thus, the intrinsic camera parameters can be calibrated beforehand using available calibration software. Furthermore, a way to segment the true coil outline in the acquired images is motivated. The proposed optimization method yields highly accurate results and can be generalized even to measure other solids which cannot be characterized by the identification of simple geometric primitives.

  15. "Coveting thy neighbour's legs": a qualitative study of exercisers' experiences of intrinsic and extrinsic goal pursuit.

    Science.gov (United States)

    Sebire, Simon J; Standage, Martyn; Gillison, Fiona B; Vansteenkiste, Maarten

    2013-06-01

    Goals are central to exercise motivation, although not all goals (e.g., health vs. appearance goals) are equally psychologically or behaviorally adaptive. Within goal content theory (Vansteenkiste, Niemiec, & Soenens, 2010), goals are adaptive to the extent to which they satisfy psychological needs for autonomy, competence, and relatedness. However, little is known about what exercisers pursuing different goals are feeling, doing, thinking, and paying attention to that may help to explain the association between goal contents and need satisfaction. Using semistructured interviews and interpretative phenomenological analysis, we explored experiences of exercise among 11 adult exercisers who reported pursuing either predominantly intrinsic or extrinsic goals. Four themes emerged: (a) observation of others and resulting emotions, (b) goal expectations and time perspective, (c) markers of progress and (d) reactions to (lack of) goal achievement. Intrinsic and extrinsic goal pursuers reported divergent experiences within these four domains. The findings illuminate potential mechanisms by which different goals may influence psychological and behavioral outcomes in the exercise context.

  16. Glutathione depletion regulates both extrinsic and intrinsic apoptotic signaling cascades independent from multidrug resistance protein 1

    OpenAIRE

    2014-01-01

    Glutathione (GSH) depletion is an important hallmark of apoptosis. We previously demonstrated that GSH depletion, by its efflux, regulates apoptosis by modulation of executioner caspase activity. However, both the molecular identity of the GSH transporter(s) involved and the signaling cascades regulating GSH loss remain obscure. We sought to determine the role of multidrug resistance protein 1 (MRP1) in GSH depletion and its regulatory role on extrinsic and intrinsic pathways of apoptosis. In...

  17. [Extrinsic allergic alveolitis: An initial form of presentation as a fever of unknown origin].

    Science.gov (United States)

    Peña Irún, A; García Pérez, M; González Santamaría, A

    2012-10-01

    Extrinsic allergic alveolitis is characterised by an inflammatory immune process with pulmonary impairment caused by inhalation of organic dust. It is considered an occupational disease and is a very significant cause of temporary and permanent disability that can be prevented. The diagnosis is not often easy, but it is important to make it in the early stages, when the disease is still reversible. Copyright © 2011 Elsevier España, S.L. y SEMERGEN. All rights reserved.

  18. Effects of extrinsic mortality on the evolution of aging: a stochastic modeling approach.

    Science.gov (United States)

    Shokhirev, Maxim Nikolaievich; Johnson, Adiv Adam

    2014-01-01

    The evolutionary theories of aging are useful for gaining insights into the complex mechanisms underlying senescence. Classical theories argue that high levels of extrinsic mortality should select for the evolution of shorter lifespans and earlier peak fertility. Non-classical theories, in contrast, posit that an increase in extrinsic mortality could select for the evolution of longer lifespans. Although numerous studies support the classical paradigm, recent data challenge classical predictions, finding that high extrinsic mortality can select for the evolution of longer lifespans. To further elucidate the role of extrinsic mortality in the evolution of aging, we implemented a stochastic, agent-based, computational model. We used a simulated annealing optimization approach to predict which model parameters predispose populations to evolve longer or shorter lifespans in response to increased levels of predation. We report that longer lifespans evolved in the presence of rising predation if the cost of mating is relatively high and if energy is available in excess. Conversely, we found that dramatically shorter lifespans evolved when mating costs were relatively low and food was relatively scarce. We also analyzed the effects of increased predation on various parameters related to density dependence and energy allocation. Longer and shorter lifespans were accompanied by increased and decreased investments of energy into somatic maintenance, respectively. Similarly, earlier and later maturation ages were accompanied by increased and decreased energetic investments into early fecundity, respectively. Higher predation significantly decreased the total population size, enlarged the shared resource pool, and redistributed energy reserves for mature individuals. These results both corroborate and refine classical predictions, demonstrating a population-level trade-off between longevity and fecundity and identifying conditions that produce both classical and non

  19. Effects of extrinsic mortality on the evolution of aging: a stochastic modeling approach.

    Directory of Open Access Journals (Sweden)

    Maxim Nikolaievich Shokhirev

    Full Text Available The evolutionary theories of aging are useful for gaining insights into the complex mechanisms underlying senescence. Classical theories argue that high levels of extrinsic mortality should select for the evolution of shorter lifespans and earlier peak fertility. Non-classical theories, in contrast, posit that an increase in extrinsic mortality could select for the evolution of longer lifespans. Although numerous studies support the classical paradigm, recent data challenge classical predictions, finding that high extrinsic mortality can select for the evolution of longer lifespans. To further elucidate the role of extrinsic mortality in the evolution of aging, we implemented a stochastic, agent-based, computational model. We used a simulated annealing optimization approach to predict which model parameters predispose populations to evolve longer or shorter lifespans in response to increased levels of predation. We report that longer lifespans evolved in the presence of rising predation if the cost of mating is relatively high and if energy is available in excess. Conversely, we found that dramatically shorter lifespans evolved when mating costs were relatively low and food was relatively scarce. We also analyzed the effects of increased predation on various parameters related to density dependence and energy allocation. Longer and shorter lifespans were accompanied by increased and decreased investments of energy into somatic maintenance, respectively. Similarly, earlier and later maturation ages were accompanied by increased and decreased energetic investments into early fecundity, respectively. Higher predation significantly decreased the total population size, enlarged the shared resource pool, and redistributed energy reserves for mature individuals. These results both corroborate and refine classical predictions, demonstrating a population-level trade-off between longevity and fecundity and identifying conditions that produce both

  20. Please Say What This Word Is ? Vowel-extrinsic normalization in the sensorimotor control of speech

    OpenAIRE

    Nicolas J. Bourguignon; Shari R Baum; Shiller, Douglas M.

    2016-01-01

    The extent to which the adaptive nature of speech perception influences the acoustic targets underlying speech production is not well understood. For example, listeners can rapidly accommodate to talker-dependent phonetic properties ? a process known as vowel-extrinsic normalization ? without altering their speech output. Recent evidence, however, shows that reinforcement-based learning in vowel perception alters the processing of speech auditory feedback, impacting sensorimotor control durin...

  1. Sequential intrinsic and extrinsic geometry calibration in fluoro CT imaging with a mobile C-arm

    Science.gov (United States)

    Cheryauka, Arvi; Breham, Sebastien; Christensen, Wayne

    2006-03-01

    Design of C-arm equipment with 3D imaging capabilitys involves retrieval of repeatable gantry positioning information along the acquisition trajectory. Inaccurate retrieval or improper use of positioning information may cause degradation of the reconstruction results, appearance of image artifacts, or indicate false structures. The geometry misrepresentation can also lead to the errors in relative pose assessment of anatomy-of-interest and interventional tools. Comprehensive C gantry calibration with an extended set of misalignment and motion parameters suffers from ambiguity caused by parameter cross-correlation and significant computational complexity. We deploy the concept of a waterfall calibration that comprises sequential intrinsic and extrinsic geometry calibration delineation steps. Following the image-based framework, the first step in our method is intrinsic calibration that deals with delineation of geometry of the X-ray tube-Detector assembly. Extrinsic parameters define motion of the C-arm assembly in 3D space and relate the Camera and World coordinate systems. We formulate both intrinsic and extrinsic calibration problems in vectorized form with total variation constraints. The proposed method has been verified by numerical design and validated by experimental studies. Sequential delineation of intrinsic and extrinsic geometries has demonstrated very efficient performance. The method eliminates the cross-correlation between cone-beam projection parameters, provides significantly better accuracy and computational speed, simplifies the structures of calibration targets used, and avoids the unnecessary workflow and image processing steps. It appears to be adequate for quality and cost derivations in an interventional surgery settings using a mobile C-arm.

  2. Charge Separation in Semicrystalline Polymeric Semiconductors by Photoexcitation: Is the Mechanism Intrinsic or Extrinsic?

    Science.gov (United States)

    Paquin, Francis; Latini, Gianluca; Sakowicz, Maciej; Karsenti, Paul-Ludovic; Wang, Linjun; Beljonne, David; Stingelin, Natalie; Silva, Carlos

    2011-05-01

    We probe charge photogeneration and subsequent recombination dynamics in neat regioregular poly(3-hexylthiophene) films over six decades in time by means of time-resolved photoluminescence spectroscopy. Exciton dissociation at 10 K occurs extrinsically at interfaces between molecularly ordered and disordered domains. Polaron pairs thus produced recombine by tunneling with distributed rates governed by the distribution of electron-hole radii. Quantum-chemical calculations suggest that hot-exciton dissociation at such interfaces results from a high charge-transfer character.

  3. Text Summarization Evaluation: Correlating Human Performance on an Extrinsic Task with Automatic Intrinsic Metrics

    Science.gov (United States)

    2006-05-01

    computed the Pearson r and Spearman ρ (Siegel and Castellan , 1988) correlation values for the comparison of the human judgments and the ROUGE scores, and...average performance of a system for all topics. Table 4.15 and Table 4.16 show the rank correlations— using Pearson r (Siegel and Castellan , 1988...Intrinsic and Extrinsic Scores Grouped by System (including Full Text) and also Spearman ρ (Siegel and Castellan , 1988) is introduced in this

  4. Modeling effects of intrinsic and extrinsic rewards on the competition between striatal learning systems.

    Science.gov (United States)

    Boedecker, Joschka; Lampe, Thomas; Riedmiller, Martin

    2013-01-01

    A common assumption in psychology, economics, and other fields holds that higher performance will result if extrinsic rewards (such as money) are offered as an incentive. While this principle seems to work well for tasks that require the execution of the same sequence of steps over and over, with little uncertainty about the process, in other cases, especially where creative problem solving is required due to the difficulty in finding the optimal sequence of actions, external rewards can actually be detrimental to task performance. Furthermore, they have the potential to undermine intrinsic motivation to do an otherwise interesting activity. In this work, we extend a computational model of the dorsomedial and dorsolateral striatal reinforcement learning systems to account for the effects of extrinsic and intrinsic rewards. The model assumes that the brain employs both a goal-directed and a habitual learning system, and competition between both is based on the trade-off between the cost of the reasoning process and value of information. The goal-directed system elicits internal rewards when its models of the environment improve, while the habitual system, being model-free, does not. Our results account for the phenomena that initial extrinsic reward leads to reduced activity after extinction compared to the case without any initial extrinsic rewards, and that performance in complex task settings drops when higher external rewards are promised. We also test the hypothesis that external rewards bias the competition in favor of the computationally efficient, but cruder and less flexible habitual system, which can negatively influence intrinsic motivation and task performance in the class of tasks we consider.

  5. Modeling effects of intrinsic and extrinsic rewards on the competition between striatal learning systems

    Directory of Open Access Journals (Sweden)

    Joschka eBoedecker

    2013-10-01

    Full Text Available A common assumption in psychology, economics, and other fields holds that higher performance will result if extrinsic rewards (such as money are offered as an incentive. While this principle seems to work well for tasks that require the execution of the same sequence of steps over and over, with little uncertainty about the process, in other cases, especially where creative problem solving is required due to the difficulty in finding the optimal sequence of actions, external rewards can actually be detrimental to task performance. Furthermore, they have the potential to undermine intrinsic motivation to do an otherwise interesting activity. In this work, we extend a computational model of the prefrontal and dorsolateral striatal reinforcement learning systems to account for the effects of extrinsic and intrinsic rewards. The model assumes that the brain employs both a goal-directed and a habitual learning system, and competition between both is based on the trade-off between the cost of the reasoning process and value of information. The goal-directed system elicits internal rewards when its models of the environment improve, while the habitual system, being model-free, does not. Our results account for the phenomena that initial extrinsic reward leads to reduced activity after extinction compared to the case without any initial extrinsic rewards, and that performance in complex task settings drops when higher external rewards are promised. We also test the hypothesis that external rewards bias the competition in favor of the computationally efficient, but cruder and less flexible habitual system, which can negatively influence intrinsic motivation and task performance in the class of tasks we consider.

  6. Modeling effects of intrinsic and extrinsic rewards on the competition between striatal learning systems

    OpenAIRE

    Joschka eBoedecker; Thomas eLampe; Martin eRiedmiller

    2013-01-01

    A common assumption in psychology, economics, and other fields holds that higher performance will result if extrinsic rewards (such as money) are offered as an incentive. While this principle seems to work well for tasks that require the execution of the same sequence of steps over and over, with little uncertainty about the process, in other cases, especially where creative problem solving is required due to the difficulty in finding the optimal sequence of actions, external rewards can actu...

  7. Modeling effects of intrinsic and extrinsic rewards on the competition between striatal learning systems

    OpenAIRE

    Joschka eBoedecker; Thomas eLampe; Martin eRiedmiller

    2013-01-01

    A common assumption in psychology, economics, and other fields holds that higher performance will result if extrinsic rewards (such as money) are offered as an incentive. While this principle seems to work well for tasks that require the execution of the same sequence of steps over and over, with little uncertainty about the process, in other cases, especially where creative problem solving is required due to the difficulty in finding the optimal sequence of actions, external rewards can actu...

  8. Careful accounting of extrinsic noise in protein expression reveals correlations among its sources

    Science.gov (United States)

    Cole, John A.; Luthey-Schulten, Zaida

    2017-06-01

    In order to grow and replicate, living cells must express a diverse array of proteins, but the process by which proteins are made includes a great deal of inherent randomness. Understanding this randomness—whether it arises from the discrete stochastic nature of chemical reactivity ("intrinsic" noise), or from cell-to-cell variability in the concentrations of molecules involved in gene expression, or from the timings of important cell-cycle events like DNA replication and cell division ("extrinsic" noise)—remains a challenge. In this article we analyze a model of gene expression that accounts for several extrinsic sources of noise, including those associated with chromosomal replication, cell division, and variability in the numbers of RNA polymerase, ribonuclease E, and ribosomes. We then attempt to fit our model to a large proteomics and transcriptomics data set and find that only through the introduction of a few key correlations among the extrinsic noise sources can we accurately recapitulate the experimental data. These include significant correlations between the rate of mRNA degradation (mediated by ribonuclease E) and the rates of both transcription (RNA polymerase) and translation (ribosomes) and, strikingly, an anticorrelation between the transcription and the translation rates themselves.

  9. Identity Processes and Intrinsic and Extrinsic Goal Pursuits: Directionality of Effects in College Students.

    Science.gov (United States)

    Luyckx, Koen; Duriez, Bart; Green, Lindsey M; Negru-Subtirica, Oana

    2017-08-01

    Identity research has mainly focused on the degree to which adolescents and emerging adults engage in exploration and commitment to identity goals and strivings. Somewhat lacking from this research tradition is an explicit focus on the content of the identity goals that individuals deem important and pursue. The present manuscript describes two longitudinal studies sampling college students in which we examine how exploration and commitment processes relate to intrinsic and extrinsic goal pursuits as defined in Self-Determination Theory. Study 1 was a two-wave longitudinal study spanning 6 months (N = 370; 77.4% women; mean age 18.24 years); Study 2 was a three-wave longitudinal study spanning 6 months (N = 458 students; 84.9% women; mean age 18.25 years). Using cross-lagged path analyses, hypotheses were supported to various degrees of convergence between studies, pointing to the extent of which results were replicated across our two independent longitudinal samples. Whereas an intrinsic goal orientation positively predicted commitment making (Study 1) and identification with commitment over time (Studies 1 and 2), an extrinsic goal orientation positively predicted ruminative exploration over time, which led to decreases in intrinsic orientation over time (Study 2). Further, an intrinsic goal orientation negatively predicted ruminative exploration over time (Study 1). The findings in for pro-active exploration processes were inconsistent across both studies, being prospectively related to both intrinsic (Study 2) and extrinsic goal orientations (Study 1). Implications and suggestions for future research are discussed.

  10. Intrinsic and extrinsic noise effects on phase transitions of network models with applications to swarming systems.

    Science.gov (United States)

    Pimentel, Jaime A; Aldana, Maximino; Huepe, Cristián; Larralde, Hernán

    2008-06-01

    We analyze order-disorder phase transitions driven by noise that occur in two kinds of network models closely related to the self-propelled model proposed by Vicsek [Phys. Rev. Lett. 75, 1226 (1995)] to describe the collective motion of groups of organisms. Two different types of noise, which we call intrinsic and extrinsic, are considered. The intrinsic noise, the one used by Vicsek in their original work, is related to the decision mechanism through which the particles update their positions. In contrast, the extrinsic noise, later introduced by Grégoire and Chaté [Phys. Rev. Lett. 92, 025702 (2004)], affects the signal that the particles receive from the environment. The network models presented here can be considered as mean-field representations of the self-propelled model. We show analytically and numerically that, for these two network models, the phase transitions driven by the intrinsic noise are continuous, whereas the extrinsic noise produces discontinuous phase transitions. This is true even for the small-world topology, which induces strong spatial correlations between the network elements. We also analyze the case where both types of noise are present simultaneously. In this situation, the phase transition can be continuous or discontinuous depending upon the amplitude of each type of noise.

  11. Comparing Effects of Intrinsic and Extrinsic Social Values Between Younger and Older Employees.

    Science.gov (United States)

    Yeung, Dannii Y; Fung, Helene H; Chan, Darius K-S

    2016-08-17

    Socioemotional selectivity theory proposes that older adults emphasize emotional goals and interpersonal closeness to a greater extent than do younger adults, suggesting that holding social work-related values (SWVs) may be beneficial to older employees. This project aimed at examining two dimensions of SWVs, intrinsic and extrinsic SWVs, and tested whether age and work situation would moderate their effects on self-rated job performance. A cross-sectional survey (Study 1, N = 357) and a 14-day experience sampling study (Study 2, N = 77) were conducted among Chinese managerial employees. Study 1 showed that the direct effect of intrinsic SWVs on self-rated job performance was stronger in older employees than in younger employees. Study 2 demonstrated that older employees who valued intrinsic SWVs while being in social situations performed much better than when they did not value intrinsic SWVs but being in social situations; however such positive effect was not shown in younger employees. Findings of this project reveal that the effect of SWVs varies across locus of effect (intrinsic versus extrinsic), age, and work situation. Among older employees, the positive effect of intrinsic SWVs is more crucial than that of extrinsic SWVs on self-rated job performance. Findings of this project imply that intrinsically rewarding incentives would be more effective in motivating older employees to reach peak performance.

  12. Combination of extrinsic and intrinsic pathways significantly accelerates axial vascularization of bioartificial tissues.

    Science.gov (United States)

    Arkudas, Andreas; Pryymachuk, Galyna; Beier, Justus P; Weigel, Linda; Körner, Carolin; Singer, Robert F; Bleiziffer, Oliver; Polykandriotis, Elias; Horch, Raymund E; Kneser, Ulrich

    2012-01-01

    In this study, the authors present a modification of the arteriovenous loop model that combines extrinsic and intrinsic vascularization modes to enhance vascularization of bioartificial matrices. An arteriovenous loop was created in the medial thighs of 24 rats. The loop was placed in a newly developed titanium chamber, which was fabricated with an electron beam melting facility, and was embedded in a hydroxyapatite/β-tricalcium phosphate/fibrin matrix. At the explantation time points (2, 4, 6, and 8 weeks), constructs were perfused by differently colored dyes to determine the amount of tissue vascularized by either the intrinsic or the extrinsic vascular pathway. Specimens were investigated by means of micro-computed tomography and histologic and morphometric analysis. Although there was an equal number of blood vessels originating from the center and the periphery, 83 percent of all vessels displayed a connection to the arteriovenous loop already at 2 weeks. There was a continuous increase of the relative proportion of vessels connected to the arteriovenous loop over time detectable. At 8 weeks, communications between the newly formed vessels and the arteriovenous loop were visible in 97 percent of all vessels. This study demonstrates for the first time the enhancement of angiogenesis in an axially vascularized tissue by an additional extrinsic vascular pathway. By 2 weeks, both pathways showed connections, allowing transplantation of the entire construct using the arteriovenous loop pedicle. This approach will allow for reduction of the time interval between arteriovenous loop implantation and transplantation into the defect site and limitation of operative interventions.

  13. Using humour as an extrinsic source of emotion regulation in young and older adults.

    Science.gov (United States)

    Harm, Jonathan; Vieillard, Sandrine; Didierjean, André

    2014-10-01

    It has been suggested that intrinsic abilities for regulating emotions remain stable or improve with ageing, but, to date, no studies have examined age-related differences in extrinsic emotion regulation. Since humour has been found to be an effective form of emotion regulation, we used a paradigm similar to that of Strick and colleagues (2009) with two objectives: to compare extrinsic humorous emotion regulation in young and older adults and to test whether the potential beneficial effect of humour on negative emotion is better explained by the cognitive distraction hypothesis or by the positive affect elicitation hypothesis. To this end, neutral, moderately, and strongly negative pictures followed by humorous, simply positive, or weird cartoons, controlled for both their funniness and cognitive demands, were presented to 26 young and 25 older adults with the instruction to report their negative feelings. When induced to feel moderately negative emotions, both young and older adults reported a lower negative feeling after viewing the humorous cartoons than after the other ones. This indicates that the extrinsic humorous emotion regulation skill remains stable with ageing and suggests that the beneficial effect of humour on emotional feeling cannot be seen as a purely cognitive distraction.

  14. Extrinsic Versus Intrinsic Benefits: Challenging Categories Used to Define the Value of Music in Schools

    Directory of Open Access Journals (Sweden)

    Alexander Hew Dale Crooke

    2016-07-01

    Full Text Available Increasing pressures to justify the value of music in schools over recent decades has led to the construction of three distinct areas of benefits: intrinsic (or musical benefits, extrinsic benefits related to academic and/or cognitive development, and extrinsic benefits related to psychosocial wellbeing. While some argue these categories have been useful for identifying specific areas of value and enabling targeted advocacy approaches, others have challenged this segmented approach to justification. While the most strident point of contention stems from the perception that categories which champion non-musical (extrinsic benefits have led to the devaluing of musical (intrinsic benefits, others dispute the categories themselves. Such arguments question the ability to separate what have been categorised as musical and non-musical elements, particularly in relation to social and political elements. This paper aims to tease out the practicality of these existing categories, and in doing so, challenge their robustness in both form and definition. The argument is made that current attempts to separate the value of school-based music into distinct categories is not only unclear, but also unhelpful in areas of advocacy. This argument rests on the premise that musical participation affords opportunities to enrich human experience in holistic and integrated ways, and that categorisation serves to preclude this unique value.

  15. The effects of non-contingent extrinsic and intrinsic rewards on memory consolidation.

    Science.gov (United States)

    Nielson, Kristy A; Bryant, Ted

    2005-07-01

    Emotional and arousing treatments given shortly after learning enhance delayed memory retrieval in animal and human studies. Positive affect and reward induced prior to a variety of cognitive tasks enhance performance, but their ability to affect memory consolidation has not been investigated before. Therefore, we investigated the effects of a small, non-contingent, intrinsic or extrinsic reward on delayed memory retrieval. Participants (n=108) studied and recalled a list of 30 affectively neutral, imageable nouns. Experimental groups were then given either an intrinsic reward (e.g., praise) or an extrinsic reward (e.g., US 1 dollar). After a one-week delay, participants' retrieval performance for the word list was significantly better in the extrinsic reward groups, whether the reward was expected or not, than in controls. Those who received the intrinsic reward performed somewhat better than controls, but the difference was not significant. Thus, at least some forms of arousal and reward, even when semantically unrelated to the learned material, can effectively modulate memory consolidation. These types of treatments might be useful for the development of new memory intervention strategies.

  16. Stac3 is a novel regulator of skeletal muscle development in mice.

    Directory of Open Access Journals (Sweden)

    Brad M Reinholt

    Full Text Available The goal of this study was to identify novel factors that mediate skeletal muscle development or function. We began the study by searching the gene expression databases for genes that have no known functions but are preferentially expressed in skeletal muscle. This search led to the identification of the Src homology three (SH3 domain and cysteine rich (C1 domain 3 (Stac3 gene. We experimentally confirmed that Stac3 mRNA was predominantly expressed in skeletal muscle. We determined if Stac3 plays a role in skeletal muscle development or function by generating Stac3 knockout mice. All Stac3 homozygous mutant mice were found dead at birth, were never seen move, and had a curved body and dropping forelimbs. These mice had marked abnormalities in skeletal muscles throughout the body, including central location of myonuclei, decreased number but increased cross-sectional area of myofibers, decreased number and size of myofibrils, disarrayed myofibrils, and streaming Z-lines. These phenotypes demonstrate that the Stac3 gene plays a critical role in skeletal muscle development and function in mice.

  17. Recent Progress in Multiparameter Measurement Based on Extrinsic Fiber-Optic Fabry-Perot Interferometers and Fiber Gratings

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    This paper presents a review of recent progress in simultaneous measurement of multiparameters including strain, temperature, vibration, transverse load, based on the combinations of extrinsic fiber-optic Fabry-Perot interferometers and fiber gratings.

  18. Intrinsic vs. extrinsic influences on life history expression: metabolism and parentally induced temperature influences on embryo development rate

    Science.gov (United States)

    Martin, Thomas E.; Ton, Riccardo; Nikilson, Alina

    2013-01-01

    Intrinsic processes are assumed to underlie life history expression and trade-offs, but extrinsic inputs are theorised to shift trait expression and mask trade-offs within species. Here, we explore application of this theory across species. We do this based on parentally induced embryo temperature as an extrinsic input, and mass-specific embryo metabolism as an intrinsic process, underlying embryonic development rate. We found that embryonic metabolism followed intrinsic allometry rules among 49 songbird species from temperate and tropical sites. Extrinsic inputs via parentally induced temperatures explained the majority of variation in development rates and masked a relationship with metabolism; metabolism explained a minor proportion of the variation in development rates among species, and only after accounting for temperature effects. We discuss evidence that temperature further obscures the expected interspecific trade-off between development rate and offspring quality. These results demonstrate the importance of considering extrinsic inputs to trait expression and trade-offs across species.

  19. The relationship between extrinsic motivation, home literacy, classroom instructional practices, and reading proficiency in second-grade Chinese children

    National Research Council Canada - National Science Library

    Yin-kum Law

    2008-01-01

      According to Wigfield (1997), children's reading motivation is multidimensional and extrinsic aspects of reading motivations include reading recognition, reading for grades, competition in reading, social reasons for reading...

  20. Differential influences of achievement approach goals and intrinsic/extrinsic motivation on help-seeking in e-learning

    National Research Council Canada - National Science Library

    Yan Yang; Li Cao

    2013-01-01

    ...’ help-seeking through intrinsic/extrinsic motivation. Path analyses were used to test two models of help-seeking among college students from four online educational psychology classes (N = 93...

  1. Long-term memory and response generalization in mushroom body extrinsic neurons in the honeybee Apis mellifera.

    Science.gov (United States)

    Haehnel, Melanie; Menzel, Randolf

    2012-02-01

    Honeybees learn to associate an odor with sucrose reward under conditions that allow the monitoring of neural activity by imaging Ca(2+) transients in morphologically identified neurons. Here we report such recordings from mushroom body extrinsic neurons - which belong to a recurrent tract connecting the output of the mushroom body with its input, potentially providing inhibitory feedback - and other extrinsic neurons. The neurons' responses to the learned odor and two novel control odors were measured 24 h after learning. We found that calcium responses to the learned odor and an odor that was strongly generalized with it were enhanced compared with responses to a weakly generalized control. Thus, the physiological responses measured in these extrinsic neurons accurately reflect what is observed in behavior. We conclude that the recorded recurrent neurons feed information back to the mushroom body about the features of learned odor stimuli. Other extrinsic neurons may signal information about learned odors to different brain regions.

  2. Effects of muscle type, castration, age, and compensatory growth rate on androgen receptor mRNA expression in bovine skeletal muscle.

    Science.gov (United States)

    Brandstetter, A M; Pfaffl, M W; Hocquette, J F; Gerrard, D E; Picard, B; Geay, Y; Sauerwein, H

    2000-03-01

    The effect of testosterone on sexual dimorphism is evident by differential growth of forelimb and neck muscles in bulls and steers. Divergent hormone sensitivites may account for the differential growth rates of individual muscles. Therefore, the objective of this study was to compare androgen receptor (AR) expression in three different muscles of bulls and steers at various ages and growth rates. Thirty Montbéliard bulls and 30 steers were assigned to four slaughter age groups. Four or five animals of each sex were slaughtered at 4 and 8 mo of age. Animals in the remaining two slaughter groups (12 and 16 mo) were divided into groups of either restricted (R) or ad libitum (AL) access to feed. Five animals of each sex and diet were slaughtered at the end of the restricted intake period at 12 mo of age. To simulate compensatory growth, the remaining animals (R and AL) were allowed ad libitum access to feed until slaughter at 16 mo of age. Total RNA was extracted from samples of semitendinosus (ST), triceps brachii (TB), and splenius (SP) muscles. Androgen receptor mRNA was quantified in 200-ng total RNA preparations using an internally standardized reverse transcription (RT) PCR assay. Data were analyzed using 18S ribosomal RNA concentrations as a covariable. Steers had higher AR mRNA levels per RNA unit than bulls (P muscles (P muscle with increasing age. Between 4 and 12 mo of age, AR mRNA levels increased (P muscle AR expression, but steers exhibiting compensatory growth had higher AR mRNA levels than AL steers (P muscle-specific and may be modulated by circulating testicular hormones. These data suggest that the regulation of AR expression may be linked to allometric muscle growth patterns in cattle and compensatory gain in steers.

  3. Muscle strain (image)

    Science.gov (United States)

    A muscle strain is the stretching or tearing of muscle fibers. A muscle strain can be caused by sports, exercise, a ... something that is too heavy. Symptoms of a muscle strain include pain, tightness, swelling, tenderness, and the ...

  4. Aging contributes to inflammation in upper extremity tendons and declines in forelimb agility in a rat model of upper extremity overuse.

    Directory of Open Access Journals (Sweden)

    David M Kietrys

    Full Text Available We sought to determine if tendon inflammatory and histopathological responses increase in aged rats compared to young rats performing a voluntary upper extremity repetitive task, and if these changes are associated with motor declines. Ninety-six female Sprague-Dawley rats were used in the rat model of upper extremity overuse: 67 aged and 29 young adult rats. After a training period of 4 weeks, task rats performed a voluntary high repetition low force (HRLF handle-pulling task for 2 hrs/day, 3 days/wk for up to 12 weeks. Upper extremity motor function was assessed, as were inflammatory and histomorphological changes in flexor digitorum and supraspinatus tendons. The percentage of successful reaches improved in young adult HRLF rats, but not in aged HRLF rats. Forelimb agility decreased transiently in young adult HRLF rats, but persistently in aged HRLF rats. HRLF task performance for 12 weeks lead to increased IL-1beta and IL-6 in flexor digitorum tendons of aged HRLF rats, compared to aged normal control (NC as well as young adult HRLF rats. In contrast, TNF-alpha increased more in flexor digitorum tendons of young adult 12-week HRLF rats than in aged HRLF rats. Vascularity and collagen fibril organization were not affected by task performance in flexor digitorum tendons of either age group, although cellularity increased in both. By week 12 of HRLF task performance, vascularity and cellularity increased in the supraspinatus tendons of only aged rats. The increased cellularity was due to increased macrophages and connective tissue growth factor (CTGF-immunoreactive fibroblasts in the peritendon. In conclusion, aged rat tendons were overall more affected by the HRLF task than young adult tendons, particularly supraspinatus tendons. Greater inflammatory changes in aged HRLF rat tendons were observed, increases associated temporally with decreased forelimb agility and lack of improvement in task success.

  5. Aging contributes to inflammation in upper extremity tendons and declines in forelimb agility in a rat model of upper extremity overuse.

    Science.gov (United States)

    Kietrys, David M; Barr-Gillespie, Ann E; Amin, Mamta; Wade, Christine K; Popoff, Steve N; Barbe, Mary F

    2012-01-01

    We sought to determine if tendon inflammatory and histopathological responses increase in aged rats compared to young rats performing a voluntary upper extremity repetitive task, and if these changes are associated with motor declines. Ninety-six female Sprague-Dawley rats were used in the rat model of upper extremity overuse: 67 aged and 29 young adult rats. After a training period of 4 weeks, task rats performed a voluntary high repetition low force (HRLF) handle-pulling task for 2 hrs/day, 3 days/wk for up to 12 weeks. Upper extremity motor function was assessed, as were inflammatory and histomorphological changes in flexor digitorum and supraspinatus tendons. The percentage of successful reaches improved in young adult HRLF rats, but not in aged HRLF rats. Forelimb agility decreased transiently in young adult HRLF rats, but persistently in aged HRLF rats. HRLF task performance for 12 weeks lead to increased IL-1beta and IL-6 in flexor digitorum tendons of aged HRLF rats, compared to aged normal control (NC) as well as young adult HRLF rats. In contrast, TNF-alpha increased more in flexor digitorum tendons of young adult 12-week HRLF rats than in aged HRLF rats. Vascularity and collagen fibril organization were not affected by task performance in flexor digitorum tendons of either age group, although cellularity increased in both. By week 12 of HRLF task performance, vascularity and cellularity increased in the supraspinatus tendons of only aged rats. The increased cellularity was due to increased macrophages and connective tissue growth factor (CTGF)-immunoreactive fibroblasts in the peritendon. In conclusion, aged rat tendons were overall more affected by the HRLF task than young adult tendons, particularly supraspinatus tendons. Greater inflammatory changes in aged HRLF rat tendons were observed, increases associated temporally with decreased forelimb agility and lack of improvement in task success.

  6. Post-stroke protection from maladaptive effects of learning with the non-paretic forelimb by bimanual home cage experience in C57BL/6 mice.

    Science.gov (United States)

    Kerr, Abigail L; Wolke, Malerie L; Bell, Jared A; Jones, Theresa A

    2013-09-01

    Behavioral experience, in the form of skilled limb use, has been found to impact the structure and function of the central nervous system, affecting post-stroke behavioral outcome in both adaptive and maladaptive ways. Learning to rely on the less-affected, or non-paretic, body side is common following stroke in both humans and rodent models. In rats, it has been observed that skilled learning with the non-paretic forelimb following ischemic insult leads to impaired or delayed functional recovery of the paretic limb. Here we used a mouse model of focal motor cortical ischemic injury to examine the effects of non-paretic limb training following unilateral stroke. In addition, we exposed some mice to increased bimanual experience in the home cage following stroke to investigate the impact of coordinated dexterous limb use on the non-paretic limb training effect. Our results confirmed that skilled learning with the non-paretic limb impaired functional recovery following stroke in C56BL/6 mice, as it does in rats. Further, this effect was avoided when the skill learning of the non-paretic limb was coupled with increased dexterous use of both forelimbs in the home cage. These findings further establish the mouse as an appropriate model in which to study the neural mechanisms of recovery following stroke and extend previous findings to suggest that the dexterous coordinated use of the paretic and non-paretic limb can promote functional outcome following injury. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. A quantitative evaluation of gross versus histologic neuroma formation in a rabbit forelimb amputation model: potential implications for the operative treatment and study of neuromas

    Directory of Open Access Journals (Sweden)

    Kuiken Todd A

    2011-10-01

    Full Text Available Abstract Background Surgical treatment of neuromas involves excision of neuromas proximally to the level of grossly "normal" fascicles; however, proximal changes at the axonal level may have both functional and therapeutic implications with regard to amputated nerves. In order to better understand the retrograde "zone of injury" that occurs after nerve transection, we investigated the gross and histologic changes in transected nerves using a rabbit forelimb amputation model. Methods Four New Zealand White rabbits underwent a forelimb amputation with transection and preservation of the median, radial, and ulnar nerves. After 8 weeks, serial sections of the amputated nerves were then obtained in a distal-to-proximal direction toward the brachial plexus. Quantitative histomorphometric analysis was performed on all nerve specimens. Results All nerves demonstrated statistically significant increases in nerve cross-sectional area between treatment and control limbs at the distal nerve end, but these differences were not observed 10 mm more proximal to the neuroma bulb. At the axonal level, an increased number of myelinated fibers were seen at the distal end of all amputated nerves. The number of myelinated fibers progressively decreased in proximal sections, normalizing at 15 mm proximally, or the level of the brachial plexus. The cross-sectional area of myelinated fibers was significantly decreased in all sections of the treatment nerves, indicating that atrophic axonal changes proceed proximally at least to the level of the brachial plexus. Conclusions Morphologic changes at the axonal level extend beyond the region of gross neuroma formation in a distal-to-proximal fashion after nerve transection. This discrepancy between gross and histologic neuromas signifies the need for improved standardization among neuroma models, while also providing a fresh perspective on how we should view neuromas during peripheral nerve surgery.

  8. Associations among teacher-student interpersonal relationships and students’ intrinsic and extrinsic motivation and academic achievement: A cross cultural study

    OpenAIRE

    Chan, Dawn

    2016-01-01

    This cross-cultural study explored associations among teacher-student relationship, students’ intrinsic and extrinsic motivation, and students’ academic achievement in grade 5 and 6 students from Vancouver, Canada (n = 102) and Hong Kong, China (n = 207). Hong Kong students perceived their teachers to be more dissatisfied, strict, admonishing, and uncertain, while Vancouver students perceived their teachers to be more helpful and friendly. Students’ levels of intrinsic and extrinsic motivatio...

  9. Associations among teacher-student interpersonal relationships and students’ intrinsic and extrinsic motivation and academic achievement: A cross cultural study

    OpenAIRE

    Chan, Dawn

    2016-01-01

    This cross-cultural study explored associations among teacher-student relationship, students’ intrinsic and extrinsic motivation, and students’ academic achievement in grade 5 and 6 students from Vancouver, Canada (n = 102) and Hong Kong, China (n = 207). Hong Kong students perceived their teachers to be more dissatisfied, strict, admonishing, and uncertain, while Vancouver students perceived their teachers to be more helpful and friendly. Students’ levels of intrinsic and extrinsic motivatio...

  10. The Influence of Intrinsic and Extrinsic Rewards on Employee Results: An Empirical Analysis in Turkish Manufacturing Industry

    OpenAIRE

    Hatice Ozutku

    2012-01-01

    The study discussed in this article questions whether certain reward practices used by organizations are better than others when comparing the employee results based on TQM. We first examine reward systems and TQM relevant literature. After related literature review, reward practices have been handled in two groups as intrinsic rewards and extrinsic rewards. In the sample, which consists of 217 businesses that operate in Turkish manufacturing industry and apply TQM, intrinsic and extrinsic re...

  11. The Influence of Intrinsic and Extrinsic Rewards on Employee Results: An Empirical Analysis in Turkish Manufacturing Industry

    OpenAIRE

    Hatice Ozutku

    2012-01-01

    The study discussed in this article questions whether certain reward practices used by organizations are better than others when comparing the employee results based on TQM. We first examine reward systems and TQM relevant literature. After related literature review, reward practices have been handled in two groups as intrinsic rewards and extrinsic rewards. In the sample, which consists of 217 businesses that operate in Turkish manufacturing industry and apply TQM, intrinsic and extrinsic re...

  12. Extrinsic attributes that influence parents' purchase of chocolate milk for their children.

    Science.gov (United States)

    Li, Xiaomeng E; Lopetcharat, Kannapon; Drake, MaryAnne

    2014-07-01

    The consumption of milk is essential for children's heath; and flavored milk, especially chocolate milk, is often purchased to increase children's milk consumption. However, the sugar content of chocolate milk has raised health concerns. As such, it is important to understand chocolate milk extrinsic attributes that influence parents' purchase decisions when they are purchasing chocolate milk for their children. The objective of this study was to determine the key extrinsic attributes for parents when they purchase chocolate milk for their children. An online survey with a conjoint analysis design, emotions questions, and Kano questionnaire that focused on chocolate milk was conducted targeting parents. Three hundred and twelve parents participated in the survey. Parents reported positive emotions including good, good natured, happy, loving, and satisfied when purchasing chocolate milk for their kids. Three segments of parents were identified with subtle but distinct differences in their key preferences for chocolate milk attributes for their children. Type of sweetener was the primary driver of choice for purchasing chocolate milk for children followed by fat content. Among sweetener types, natural noncaloric/nonnutritive sweeteners or sucrose were preferred over artificial sweeteners, and reduced fat was preferred over full fat or skim milk. Kano results revealed that reduced fat and sugar with an all natural label and added vitamins, minerals, and protein were attractive to the majority of parents when purchasing chocolate milk for their kids. Understanding the driving extrinsic attributes for parents when they purchase chocolate milk for their children will assist manufacturers to target extrinsic attributes that are attractive to parents for chocolate milk. This study established that sweetener type and fat content are the primary extrinsic attributes affecting parents purchase decisions when choosing chocolate milk for their children. Different segments of

  13. Regeneration of surgically created mixed-handed axolotl forelimbs: pattern formation in the dorsal-ventral axis.

    Science.gov (United States)

    Holder, N; Weekes, C

    1984-08-01

    The regeneration of surgically created mixed-handed limb stumps is examined in the axolotl. Operations were performed in the lower arm and upper arm regions and grafts were allowed to heal for approximately one month prior to amputation or were amputated immediately. In the lower arm group both anterior and posterior limb halves were inverted, whereas only posterior halves were inverted in the upper arm group. Almost all the limbs regenerated were normal in the anterior-posterior axis, whereas a range of limb types were found when the dorsal-ventral axis was analysed using the metacarpal muscle pattern and epidermal Leydig cell number as positional markers. The carpal and forearm muscle patterns were also analysed in order to assess whether the pattern determined from analysis at the metacarpal level reflected that seen at more proximal levels. The results are discussed in terms of the possible role of cell contribution from the stump to the blastema and the relevance of the study to models of pattern regulation.

  14. Jaw muscles of Old World squirrels.

    Science.gov (United States)

    Thorington, R W; Darrow, K

    1996-11-01

    The jaw, suprahyoid, and extrinsic tongue muscles were studied in 11 genera, belonging to five tribes, of Old World squirrels. Significant variation in most of the adductor muscles is evident. The most primitive state of sciuromorphy is seen in the African tree squirrels Paraxerus and Funisciurus, especially as reflected in the anterior deep masseter. A derived state of sciuromorphy is found in five genera of Old World squirrels and perhaps evolved independently in each. Reduction of the temporalis muscle was observed in three genera, distantly related to one another. A unique arrangement of the superficial masseter is reported in the Asian giant tree squirrels, Ratufa. The arrangement of the masseter in the African pygmy squirrel, Myosciurus, is very similar to that of the South American pygmy squirrel, Sciurillus. We present hypotheses about the functional significance of these differences. In the derived state of sciuromorphy, which is found in three cases in squirrels that feed extensively on hard fruits, the anterior deep masseter is well positioned to increase the strength of the power stroke of the incisor bite. Among the pygmy squirrels, the position of the anterior deep masseter suggests that it plays a more significant role in molar chewing.

  15. Jaw muscles of New World squirrels.

    Science.gov (United States)

    Ball, S S; Roth, V L

    1995-06-01

    The jaw, suprahyoid, and extrinsic tongue muscles are described for eight species of New World squirrels, spanning more than an order of magnitude in body mass. Anatomical differences are discussed in the light of body size, natural history, and phylogeny. The relative sizes of different muscles, their orientations, and the shapes and positions of their areas of attachment vary but show few trends in relation to body size. The anatomical differences are likewise not readily explained by the mechanical requirements of the animals' diets, which are similar. The most marked anatomical differences occur in Sciurillus (the pygmy tree squirrel), as well as those genera--Glaucomys (the flying squirrel) and Tamias (the chipmunk)--that are taxonomically most distinct from the tree squirrels. Sciurillus is noteworthy for its unusually small temporalis and an anterior deep masseter that is oriented to assist in retraction of the jaw. Tamias has a more vertically oriented temporalis and greater inclination in the anterior masseter muscles than the other squirrels, features that may be associated with its large diastema and relatively posteriorly situated cheek teeth, which in turn may relate to its having cheek pouches. Our results form a valuable database of information to be used in further studies of functional morphology and phylogeny.

  16. Diversity in the organization of elastin bundles and intramembranous muscles in bat wings.

    Science.gov (United States)

    Cheney, Jorn A; Allen, Justine J; Swartz, Sharon M

    2017-04-01

    Unlike birds and insects, bats fly with wings composed of thin skin that envelops the bones of the forelimb and spans the area between the limbs, digits, and sometimes the tail. This skin is complex and unusual; it is thinner than typical mammalian skin and contains organized bundles of elastin and embedded skeletal muscles. These elements are likely responsible for controlling the shape of the wing during flight and contributing to the aerodynamic capabilities of bats. We examined the arrangement of two macroscopic architectural elements in bat wings, elastin bundles and wing membrane muscles, to assess the diversity in bat wing skin morphology. We characterized the plagiopatagium and dactylopatagium of 130 species from 17 families of bats using cross-polarized light imaging. This method revealed structures with distinctive relative birefringence, heterogeneity of birefringence, variation in size, and degree of branching. We used previously published anatomical studies and tissue histology to identify birefringent structures, and we analyzed their architecture across taxa. Elastin bundles, muscles, neurovasculature, and collagenous fibers are present in all species. Elastin bundles are oriented in a predominantly spanwise or proximodistal direction, and there are five characteristic muscle arrays that occur within the plagiopatagium, far more muscle than typically recognized. These results inform recent functional studies of wing membrane architecture, support the functional hypothesis that elastin bundles aid wing folding and unfolding, and further suggest that all bats may use these architectural elements for flight. All species also possess numerous muscles within the wing membrane, but the architecture of muscle arrays within the plagiopatagium varies among families. To facilitate present and future discussion of these muscle arrays, we refine wing membrane muscle nomenclature in a manner that reflects this morphological diversity. The architecture of the

  17. Involvement of eicosanoids and surfactant protein D in extrinsic allergic alveolitis.

    Science.gov (United States)

    Higashi, A; Higashi, N; Tsuburai, T; Takeuchi, Y; Taniguchi, M; Mita, H; Saito, A; Takatori, K; Arimura, K; Akiyama, K

    2005-12-01

    The pathophysiology of extrinsic allergic alveolitis (EAA) involves oxidative lung damage as well as interstitial and alveolar inflammation. Macrophages and mast cells are inflammatory components of EAA that produce both leukotrienes (LTs) and prostaglandin D2 (PGD2). In addition, PGD2 is also produced by the free-radical-catalysed peroxidation of arachidonic acid during oxidative stress. Urinary 8-iso prostaglandin F2alpha (8-isoPGF2alpha) and serum surfactant protein D (SP-D) are considered appropriate biomarkers of oxidative stress and interstitial lung disease activity, respectively. The present study aimed to assess the association of these biomarkers with the pathophysiology of EAA. Two cases of acute EAA caused by the inhalation of fungi spores were reported. Eight asthmatic patients and six healthy control subjects were also enrolled in the current study. The serum SP-D and urinary eicosanoid (LTE4, PGD2 metabolite (9alpha,11betaPGF2), 8-isoPGF2alpha) concentrations markedly increased during the acute exacerbation phase. These concentrations decreased following corticosteroid therapy in the EAA patients. There was a significant correlation between serum SP-D and urinary 9alpha,11betaPGF2 concentrations in the EAA patients. In conclusion, although the present study proposes that serum surfactant protein-D and urinary eicosanoids are new biomarkers involved in the various immunological responses in extrinsic allergic alveolitis, further large-scale studies are needed to investigate the role of these compounds, not just as biomarkers, but also as biological potentiators of extrinsic allergic alveolitis.

  18. Providing Extrinsic Reward for Test Performance Undermines Long-Term Memory Acquisition

    Directory of Open Access Journals (Sweden)

    Christof eKuhbandner

    2016-02-01

    Full Text Available Based on numerous studies showing that testing studied material can improve long-term retention more than restudying the same material, it is often suggested that the number of tests in education should be increased to enhance knowledge acquisition. However, testing in real-life educational settings often entails a high degree of extrinsic motivation of learners due to the common practice of placing important consequences on the outcome of a test. Such an effect on the motivation of learners may undermine the beneficial effects of testing on long-term memory because it has been shown that extrinsic motivation can reduce the quality of learning. To examine this issue, participants learned foreign language vocabulary words, followed by an immediate test in which one third of the words were tested and one third restudied. To manipulate extrinsic motivation during immediate testing, participants received either monetary reward contingent on test performance or no reward. After one week, memory for all words was tested. In the immediate test, reward reduced correct recall and increased commission errors, indicating that reward reduced the number of items that can benefit from successful retrieval. The results in the delayed test revealed that reward additionally reduced the gain received from successful retrieval because memory for initially successfully retrieved words was lower in the reward condition. However, testing was still more effective than restudying under reward conditions because reward undermined long-term memory for concurrently restudied material as well. These findings indicate that providing performance-contingent reward in a test can undermine long-term knowledge acquisition.

  19. Providing Extrinsic Reward for Test Performance Undermines Long-Term Memory Acquisition.

    Science.gov (United States)

    Kuhbandner, Christof; Aslan, Alp; Emmerdinger, Kathrin; Murayama, Kou

    2016-01-01

    Based on numerous studies showing that testing studied material can improve long-term retention more than restudying the same material, it is often suggested that the number of tests in education should be increased to enhance knowledge acquisition. However, testing in real-life educational settings often entails a high degree of extrinsic motivation of learners due to the common practice of placing important consequences on the outcome of a test. Such an effect on the motivation of learners may undermine the beneficial effects of testing on long-term memory because it has been shown that extrinsic motivation can reduce the quality of learning. To examine this issue, participants learned foreign language vocabulary words, followed by an immediate test in which one-third of the words were tested and one-third restudied. To manipulate extrinsic motivation during immediate testing, participants received either monetary reward contingent on test performance or no reward. After 1 week, memory for all words was tested. In the immediate test, reward reduced correct recall and increased commission errors, indicating that reward reduced the number of items that can benefit from successful retrieval. The results in the delayed test revealed that reward additionally reduced the gain received from successful retrieval because memory for initially successfully retrieved words was lower in the reward condition. However, testing was still more effective than restudying under reward conditions because reward undermined long-term memory for concurrently restudied material as well. These findings indicate that providing performance-contingent reward in a test can undermine long-term knowledge acquisition.

  20. Providing Extrinsic Reward for Test Performance Undermines Long-Term Memory Acquisition

    Science.gov (United States)

    Kuhbandner, Christof; Aslan, Alp; Emmerdinger, Kathrin; Murayama, Kou

    2016-01-01

    Based on numerous studies showing that testing studied material can improve long-term retention more than restudying the same material, it is often suggested that the number of tests in education should be increased to enhance knowledge acquisition. However, testing in real-life educational settings often entails a high degree of extrinsic motivation of learners due to the common practice of placing important consequences on the outcome of a test. Such an effect on the motivation of learners may undermine the beneficial effects of testing on long-term memory because it has been shown that extrinsic motivation can reduce the quality of learning. To examine this issue, participants learned foreign language vocabulary words, followed by an immediate test in which one-third of the words were tested and one-third restudied. To manipulate extrinsic motivation during immediate testing, participants received either monetary reward contingent on test performance or no reward. After 1 week, memory for all words was tested. In the immediate test, reward reduced correct recall and increased commission errors, indicating that reward reduced the number of items that can benefit from successful retrieval. The results in the delayed test revealed that reward additionally reduced the gain received from successful retrieval because memory for initially successfully retrieved words was lower in the reward condition. However, testing was still more effective than restudying under reward conditions because reward undermined long-term memory for concurrently restudied material as well. These findings indicate that providing performance–contingent reward in a test can undermine long-term knowledge acquisition. PMID:26869978

  1. Combined model of intrinsic and extrinsic variability for computational network design with application to synthetic biology.

    Directory of Open Access Journals (Sweden)

    Tina Toni

    Full Text Available Biological systems are inherently variable, with their dynamics influenced by intrinsic and extrinsic sources. These systems are often only partially characterized, with large uncertainties about specific sources of extrinsic variability and biochemical properties. Moreover, it is not yet well understood how different sources of variability combine and affect biological systems in concert. To successfully design biomedical therapies or synthetic circuits with robust performance, it is crucial to account for uncertainty and effects of variability. Here we introduce an efficient modeling and simulation framework to study systems that are simultaneously subject to multiple sources of variability, and apply it to make design decisions on small genetic networks that play a role of basic design elements of synthetic circuits. Specifically, the framework was used to explore the effect of transcriptional and post-transcriptional autoregulation on fluctuations in protein expression in simple genetic networks. We found that autoregulation could either suppress or increase the output variability, depending on specific noise sources and network parameters. We showed that transcriptional autoregulation was more successful than post-transcriptional in suppressing variability across a wide range of intrinsic and extrinsic magnitudes and sources. We derived the following design principles to guide the design of circuits that best suppress variability: (i high protein cooperativity and low miRNA cooperativity, (ii imperfect complementarity between miRNA and mRNA was preferred to perfect complementarity, and (iii correlated expression of mRNA and miRNA--for example, on the same transcript--was best for suppression of protein variability. Results further showed that correlations in kinetic parameters between cells affected the ability to suppress variability, and that variability in transient states did not necessarily follow the same principles as variability in

  2. Extrinsic reference frames modify the neural substrates of object-location representations.

    Science.gov (United States)

    Chan, Edgar; Baumann, Oliver; Bellgrove, Mark A; Mattingley, Jason B

    2013-04-01

    The ability to form spatial representations of object locations is an important component of successful spatial navigation. Evidence from behavioral studies suggests that environmental features that have a salient coordinate axis (e.g., a rectangular building or a geometrical room) may provide a reference frame for the encoding of object-location information. Here we used functional magnetic resonance imaging (fMRI) to determine the brain networks engaged when object-location representations are stored with respect to an extrinsic reference frame. Participants learned the layout of an object array in an active, virtual-navigation paradigm. A square mat positioned on the floor of the virtual arena acted as the extrinsic reference frame. Knowledge of the spatial arrangement of the object array was probed while participants underwent fMRI, using a spatial judgment task that required them to imagine orientations of the learned array that were either aligned or misaligned with the geometry of the mat. Consistent with previous findings, participants responded faster and were more accurate when the imagined orientation was aligned, as opposed to misaligned, with the extrinsic reference frame. Analysis of the fMRI data revealed important differences in brain activity between the two conditions. Significantly greater activity was observed in the aligned condition compared with the misaligned condition across a bilateral network of brain areas that included the inferior occipital gyri, inferior and middle temporal gyri, and fusiform gyri. By contrast, activity in the misaligned condition was significantly greater than in the aligned condition in bilateral dorsolateral prefrontal and anterior cingulate cortex, and in the right anterior prefrontal and anterior insular cortex. These results suggest that retrieval of spatial locations that are aligned with an extrinsic reference frame involve direct access to detailed and accurate representations within the ventral visual

  3. Extrinsic coefficient charcterisation of PZT ceramics near the morphotropic phase boundary

    Directory of Open Access Journals (Sweden)

    Albareda, A.

    2006-06-01

    Full Text Available PZT ceramics with high piezoelectric coefficients have high extrinsic contributions. This extrinsic behaviour, which is related to the domain wall movement, produces high non-linear effects that are sometimes inconvenient, for example when it increases the losses in power devices. The relation between extrinsic behaviour and non-linearities could be used to provide a good extrinsic characterization of materials in order to optimise the piezoelectric devices. In all cases the physical explanation of the behaviour is sought. The aim of this work is to study the dependence of the linear and non-linear dielectric, piezoelectric and mechanical coefficients on the Ti fraction in PZT ceramic compositions near the morphotropic phase boundary (MPB. The dependence of these coefficients on the defect concentration is also analysed. Hard ceramics belonging to Ferroperm Piezoceramics, with two different acceptor dopant levels, high and low, have been measured.

    Las cerámicas PZT con coeficientes piezoeléctricos elevados poseen contribuciones extrínsecas grandes. Este comportamiento extrínseco, relacionado con el movimiento de las paredes de los dominios, comporta efectos no lineales grandes que no siempre son deseables, por ejemplo, al incrementar las pérdidas de los dispositivos piezoeléctricos. Esta correspondencia entre efectos extrínsecos y no linealidades puede ser utilizada para caracterizar las cerámicas con el fin de optimizar sus propiedades piezoeléctricas. En todos los casos se busca una interpretación física de los resultados obtenidos. El objetivo de este trabajo es el estudio de la dependencia de los coeficientes lineales y no lineales dieléctricos, piezoeléctricos y elásticos con la fracción de Ti en cerámicas PZT con composiciones de Zr-Ti cerca de la transición de fase morfotrópica (MPB. También se analiza la dependencia de estos coeficientes con la concentración de impurezas, utilizando para ello cerámicas de

  4. New occupational and environmental causes of asthma and extrinsic allergic alveolitis.

    Science.gov (United States)

    Fishwick, David

    2012-12-01

    Asthma and extrinsic allergic alveolitis (EAA) remain prevalent respiratory diseases and the cause of a significant disease burden. This article reviews the recent occupational and environmental causes described for these conditions. Even over the limited time spam addressed by this article, novel agents and new data relating to already suggested causes have been described. Various types of work tasks or exposures are described that appear to cause both asthma and EAA. Isocyanates, the best example of dual potential to cause asthma and EAA are discussed, as is the new understanding of the role metal-working fluids play when causing respiratory diseases. Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.

  5. Statistical analysis of intrinsic and extrinsic coupling losses for step-index polymer optical fibers.

    Science.gov (United States)

    Werzinger, Stefan; Bunge, Christian-Alexander

    2015-08-24

    The intrinsic and extrinsic coupling losses of step-index polymer optical fibers are statistically examined by Monte Carlo simulations. In contrast to most existing models that linearly scale individual losses, a comprehensive analytic coupling loss model is used that also considers the interdependencies between mismatches in numerical aperture and core diameter, as well as radial and longitudinal offsets. As a typical example, the coupling losses of A4a.2 step-index multimode fibers are analyzed for an equilibrium mode distribution. The results show considerably less conservative coupling loss estimations than with traditional models, improving link power budgeting.

  6. Intrinsic and Extrinsic Motivation Among Adolescent Ten-Pin Bowlers in Kuala Lumpur, Malaysia

    OpenAIRE

    Teo Eng-Wah; Khoo Selina; Wong Rebecca; Wee Eng-Hoe; Lim Boon-Hooi; Rengasamy Shabesan Sit

    2015-01-01

    Motivation has long been associated with sports engagement. However, to date no research has been performed to understand the domain of motivation among ten-pin bowlers. The purpose of this study was to investigate different types of motivation (i.e., intrinsic vs. extrinsic) based on self-determination theory from the perspective of gender and the bowler type (competitive vs. casual). A total of 240 bowlers (104 male, 136 female; 152 competitive, 88 casual) with a mean age of 16.61 ± 0.78 ye...

  7. Extrinsic spin Hall effect induced by resonant skew scattering in graphene.

    Science.gov (United States)

    Ferreira, Aires; Rappoport, Tatiana G; Cazalilla, Miguel A; Castro Neto, A H

    2014-02-14

    We show that the extrinsic spin Hall effect can be engineered in monolayer graphene by decoration with small doses of adatoms, molecules, or nanoparticles originating local spin-orbit perturbations. The analysis of the single impurity scattering problem shows that intrinsic and Rashba spin-orbit local couplings enhance the spin Hall effect via skew scattering of charge carriers in the resonant regime. The solution of the transport equations for a random ensemble of spin-orbit impurities reveals that giant spin Hall currents are within the reach of the current state of the art in device fabrication. The spin Hall effect is robust with respect to thermal fluctuations and disorder averaging.

  8. Intrinsic and extrinsic motivation as predictors of work effort: the moderating role of achievement goals.

    Science.gov (United States)

    Dysvik, Anders; Kuvaas, Bård

    2013-09-01

    This research explored the roles of intrinsic motivation (IM) and extrinsic motivation (EM) and the 2 × 2 model of achievement goals as predictors of increased work effort (WE). A cross-lagged field study was conducted among 1,441 employees from three large Norwegian service organizations across a 10-month time span. The results showed that the relationship between IM and increased WE was more positive for employees with high levels of mastery-approach goals. This observation suggests that having congruent goals may accentuate the positive relationship between IM and WE. © 2012 The British Psychological Society.

  9. The impact of intrinsic and extrinsic factors on the job satisfaction of dentists.

    Science.gov (United States)

    Goetz, K; Campbell, S M; Broge, B; Dörfer, C E; Brodowski, M; Szecsenyi, J

    2012-10-01

    The Two-Factor Theory of job satisfaction distinguishes between intrinsic-motivation (i.e. recognition, responsibility) and extrinsic-hygiene (i.e. job security, salary, working conditions) factors. The presence of intrinsic-motivation facilitates higher satisfaction and performance, whereas the absences of extrinsic factors help mitigate against dissatisfaction. The consideration of these factors and their impact on dentists' job satisfaction is essential for the recruitment and retention of dentists. The objective of the study is to assess the level of job satisfaction of German dentists and the factors that are associated with it. This cross-sectional study was based on a job satisfaction survey. Data were collected from 147 dentists working in 106 dental practices. Job satisfaction was measured with the 10-item Warr-Cook-Wall job satisfaction scale. Organizational characteristics were measured with two items. Linear regression analyses were performed in which each of the nine items of the job satisfaction scale (excluding overall satisfaction) were handled as dependent variables. A stepwise linear regression analysis was performed with overall job satisfaction as the dependent outcome variable, the nine items of job satisfaction and the two items of organizational characteristics controlled for age and gender as predictors. The response rate was 95.0%. Dentists were satisfied with 'freedom of working method' and mostly dissatisfied with their 'income'. Both variables are extrinsic factors. The regression analyses identified five items that were significantly associated with each item of the job satisfaction scale: 'age', 'mean weekly working time', 'period in the practice', 'number of dentist's assistant' and 'working atmosphere'. Within the stepwise linear regression analysis the intrinsic factor 'opportunity to use abilities' (β = 0.687) showed the highest score of explained variance (R(2) = 0.468) regarding overall job satisfaction. With respect to the Two

  10. Intrinsic and Extrinsic Motivation Among Adolescent Ten-Pin Bowlers in Kuala Lumpur, Malaysia

    OpenAIRE

    Teo Eng-Wah; Khoo Selina; Wong Rebecca; Wee Eng-Hoe; Lim Boon-Hooi; Rengasamy Shabesan Sit

    2015-01-01

    Motivation has long been associated with sports engagement. However, to date no research has been performed to understand the domain of motivation among ten-pin bowlers. The purpose of this study was to investigate different types of motivation (i.e., intrinsic vs. extrinsic) based on self-determination theory from the perspective of gender and the bowler type (competitive vs. casual). A total of 240 bowlers (104 male, 136 female; 152 competitive, 88 casual) with a mean age of 16.61 ± 0.78 ye...

  11. Compensation of home health, public health, and hospital nurses. Extrinsic and intrinsic rewards.

    Science.gov (United States)

    Hughes, K K; Marcantonio, R J

    1991-11-01

    Despite the proliferation of home health agencies and increased numbers of nurses working in these settings, little is known about home health nurses or how they might differ from their public health and hospital counterparts. The authors discuss differences in monetary compensation and skill usage, as well as the relationship between compensation and retention, among hospital, home health, and public health staff nurses. The results show that these nurses receive different intrinsic and extrinsic rewards and that their reasons for remaining with their employers are similar, yet unique. Implications for nurse administrators and educators are discussed, along with recommendations for further research.

  12. A review of sensory and instrumental methods used to evaluate the texture of fish muscle

    DEFF Research Database (Denmark)

    Hyldig, Grethe; Nielsen, Durita

    2001-01-01

    The texture of fish muscle is an important quality attribute that depends on several parameters, both intrinsic and extrinsic. Its evaluation by sensory means is the result of a combination of several parameters that cover every impression from when the fish first comes into contact with a surface...... in the mouth, until it is completely masticated. This makes texture difficult to describe and evaluate. In addition the muscle structure of fish is not homogenous, and this has important implications on texture measurements by instrumental means. Numerous instrumental and sensory methods have been used...... to evaluate the texture of fish and fish fillets, with varying results and there exists no universal recommended method....

  13. The effects of denervation, reinnervation, and muscle imbalance on functional muscle length and elbow flexion contracture following neonatal brachial plexus injury.

    Science.gov (United States)

    Weekley, Holly; Nikolaou, Sia; Hu, Liangjun; Eismann, Emily; Wylie, Christopher; Cornwall, Roger

    2012-08-01

    The pathophysiology of paradoxical elbow flexion contractures following neonatal brachial plexus injury (NBPI) is incompletely understood. The current study tests the hypothesis that this contracture occurs by denervation-induced impairment of elbow flexor muscle growth. Unilateral forelimb paralysis was created in mice in four neonatal (5-day-old) BPI groups (C5-6 excision, C5-6 neurotomy, C5-6 neurotomy/repair, and C5-T1 global excision), one non-neonatal BPI group (28-day-old C5-6 excision), and two neonatal muscle imbalance groups (triceps tenotomy ± C5-6 excision). Four weeks post-operatively, motor function, elbow range of motion, and biceps/brachialis functional lengths were assessed. Musculocutaneous nerve (MCN) denervation and reinnervation were assessed immunohistochemically. Elbow flexion motor recovery and elbow flexion contractures varied inversely among the neonatal BPI groups. Contracture severity correlated with biceps/brachialis shortening and MCN denervation (relative axon loss), with no contractures occurring in mice with MCN reinnervation (presence of growth cones). No contractures or biceps/brachialis shortening occurred following non-neonatal BPI, regardless of denervation or reinnervation. Neonatal triceps tenotomy did not cause contractures or biceps/brachialis shortening, nor did it worsen those following neonatal C5-6 excision. Denervation-induced functional shortening of elbow flexor muscles leads to variable elbow flexion contractures depending on the degree, permanence, and timing of denervation, independent of muscle imbalance. Copyright © 2012 Orthopaedic Research Society.

  14. Muscle disease.

    Science.gov (United States)

    Tsao, Chang-Yong

    2014-02-01

    On the basis of strong research evidence, Duchenne muscular dystrophy (DMD), the most common severe childhood form of muscular dystrophy, is an X-linked recessive disorder caused by out-of-frame mutations of the dystrophin gene. Thus, it is classified asa dystrophinopathy. The disease onset is before age 5 years. Patients with DMD present with progressive symmetrical limb-girdle muscle weakness and become wheelchair dependent after age 12 years. (2)(3). On the basis of some research evidence,cardiomyopathy and congestive heart failure are usually seen in the late teens in patients with DMD. Progressive scoliosis and respiratory in sufficiency often develop once wheelchair dependency occurs. Respiratory failure and cardiomyopathy are common causes of death, and few survive beyond the third decade of life. (2)(3)(4)(5)(6)(7). On the basis of some research evidence, prednisone at 0.75 mg/kg daily (maximum dose, 40 mg/d) or deflazacort at 0.9 mg/kg daily (maximum dose, 39 mg/d), a derivative of prednisolone (not available in the United States), as a single morning dose is recommended for DMD patients older than 5 years, which may prolong independent walking from a few months to 2 years. (2)(3)(16)(17). Based on some research evidence, treatment with angiotensin-converting enzyme inhibitors, b-blockers, and diuretics has been reported to be beneficial in DMD patients with cardiac abnormalities. (2)(3)(5)(18). Based on expert opinion, children with muscle weakness and increased serum creatine kinase levels may be associated with either genetic or acquired muscle disorders (Tables 1 and 3). (14)(15)

  15. Muscle channelopathies.

    Science.gov (United States)

    Statland, Jeffrey; Phillips, Lauren; Trivedi, Jaya R

    2014-08-01

    Skeletal muscle channelopathies are rare heterogeneous diseases with marked genotypic and phenotypic variability. Despite advances in understanding of the molecular pathology of these disorders, the diverse phenotypic manifestations remain a challenge in diagnosis and therapeutics. These disorders can cause lifetime disability and affect quality of life. There is no treatment of these disorders approved by the US Food and Drug Administration at this time. Recognition and treatment of symptoms might reduce morbidity and improve quality of life. This article summarizes the clinical manifestations, diagnostic studies, pathophysiology, and treatment options in nondystrophic myotonia, congenital myasthenic syndrome, and periodic paralyses. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Spinal interneurons facilitate coactivation of hand muscles during a precision grip task in monkeys.

    Science.gov (United States)

    Takei, Tomohiko; Seki, Kazuhiko

    2010-12-15

    Grasping is a highly complex movement requiring coordination of a number of hand joints and muscles. In contrast to cortical descending systems, the contribution of the subcortical system for coordinating this higher degree of freedom is largely unknown. Here we explore how spinal interneurons (INs) contribute to the coordination of hand muscles by recording their activity from the cervical spinal cord (C5-T1) simultaneously with electromyographic (EMG) activity from hand and arm muscles in three monkeys performing a precision grip task. Spike-triggered averages of the rectified EMGs were compiled for 255 neurons (4821 neuron-muscle pairs). Twenty-six neurons produced 68 significant postspike effects in hand and arm muscles and were identified as premotor interneurons (PreM-INs), which presumably have relatively direct synaptic effects on spinal motoneurons. The majority of the PreM-INs (22/26 neurons) produced postspike effects in finger muscles (intrinsic and extrinsic hand muscles) compared with wrist (9/26 neurons) and elbow muscles (1/26 neurons). The effects in finger muscles were mostly facilitative [postspike facilitations (PSFs), 19/22 neurons], and few had suppressive effects (postspike suppressions, 3/22 neurons). Moreover, PreM-INs produced more divergent PSFs in intrinsic hand muscles (2.5 ± 1.9 muscles/neuron) than in wrist muscles (1.2 ± 0.4 muscles/neurons). We conclude that spinal PreM-INs produce divergent facilitations preferentially in intrinsic hand muscles. These results suggest that spinal interneurons contribute to the control of hand grasping in primates by combining and coordinating multiple finger muscles.

  17. A motor and a brake: two leg extensor muscles acting at the same joint manage energy differently in a running insect.

    Science.gov (United States)

    Ahn, A N; Full, R J

    2002-02-01

    The individual muscles of a multiple muscle group at a given joint are often assumed to function synergistically to share the load during locomotion. We examined two leg extensors of a running cockroach to test the hypothesis that leg muscles within an anatomical muscle group necessarily manage (i.e. produce, store, transmit or absorb) energy similarly during running. Using electromyographic and video motion-analysis techniques, we determined that muscles 177c and 179 are both active during the first half of the stance period during muscle shortening. Using the in vivo strain and stimulation patterns determined during running, we measured muscle power output. Although both muscles were stimulated during the first half of shortening, muscle 177c generated mechanical energy (28 W x kg(-1)) like a motor, while muscle 179 absorbed energy (-19 W x kg(-1)) like a brake. Both muscles exhibited nearly identical intrinsic characteristics including similar twitch kinetics and force-velocity relationships. Differences in the extrinsic factors of activation and relative shortening velocity caused the muscles to operate very differently during running. Presumed redundancy in a multiple muscle group may, therefore, represent diversity in muscle function. Discovering how muscles manage energy during behavior requires the measurement of a large number of dynamically interacting variables.

  18. Analyzing the microfoundations of human violence in the DRC - intrinsic and extrinsic rewards and the prediction of appetitive aggression.

    Science.gov (United States)

    Haer, Roos; Banholzer, Lilli; Elbert, Thomas; Weierstall, Roland

    2013-05-17

    Civil wars are characterized by intense forms of violence, such as torture, maiming and rape. Political scientists suggest that this form of political violence is fostered through the provision of particular intrinsic and extrinsic rewards to combatants. In the field of psychology, the perpetration of this kind of cruelty is observed to be positively linked to appetitive aggression. Over time, combatants start to enjoy the fights and even the perpetration of atrocities. In this study, we examine how receiving rewards (intrinsic versus extrinsic) influence the level of appetitive aggression exhibited by former combatants. We surveyed 95 former combatants in the eastern provinces of the Democratic Republic of the Congo. Linear regression analyses reveal that intrinsic as well as extrinsic rewards are linked to the former combatants' Appetitive Aggression score. However, this relationship is partly determined by the way in which combatants are recruited: While abducted combatants seem to react more strongly to extrinsic rewards, the score of those that joined voluntarily is primarily determined by intrinsic rewards. We conclude that receiving rewards influence the level of appetitive aggression. However, which type of rewards (intrinsic versus extrinsic) is of most importance is determined by the way combatants are recruited.

  19. Diminished Foot and Ankle Muscle Volumes in Young Adults With Chronic Ankle Instability

    Science.gov (United States)

    Feger, Mark A.; Snell, Shannon; Handsfield, Geoffrey G.; Blemker, Silvia S.; Wombacher, Emily; Fry, Rachel; Hart, Joseph M.; Saliba, Susan A.; Park, Joseph S.; Hertel, Jay

    2016-01-01

    Background: Patients with chronic ankle instability (CAI) have demonstrated altered neuromuscular function and decreased muscle strength when compared with healthy counterparts without a history of ankle sprain. Up to this point, muscle volumes have not been analyzed in patients with CAI to determine whether deficits in muscle size are present following recurrent sprain. Purpose: To analyze intrinsic and extrinsic foot and ankle muscle volumes and 4-way ankle strength in young adults with and without CAI. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Five patients with CAI (mean age, 23.0 ± 4 years; 1 male, 4 females) and 5 healthy controls (mean age, 23.8 ± 4.5 years; 1 male, 4 females) volunteered for this study. Novel fast-acquisition magnetic resonance imaging (MRI) was used to scan from above the femoral condyles through the foot and ankle. The perimeter of each muscle was outlined on each axial slice and then the 2-dimensional area was multiplied by the slice thickness (5 mm) to calculate the muscle volume. Plantar flexion, dorsiflexion, inversion, and eversion isometric strength were measured using a handheld dynamometer. Patients with CAI were compared with healthy controls on all measures of muscle volume and strength. Extrinsic muscle volumes of patients with CAI were also compared with a normative database of healthy controls (n = 24) by calculating z scores for each muscle individually for each CAI subject. Results: The CAI group had smaller total shank, superficial posterior compartment, soleus, adductor hallucis obliqus, and flexor hallucis brevis muscle volumes compared with healthy controls as indicated by group means and associated 90% CIs that did not overlap. Cohen d effect sizes for the significant group differences were all large and ranged from 1.46 to 3.52, with 90% CIs that did not cross zero. The CAI group had lower eversion, dorsiflexion, and 4-way composite ankle strength, all with group means and associated 90

  20. Mapping ECoG channel contributions to trajectory and muscle activity prediction in human sensorimotor cortex

    Science.gov (United States)

    Nakanishi, Yasuhiko; Yanagisawa, Takufumi; Shin, Duk; Kambara, Hiroyuki; Yoshimura, Natsue; Tanaka, Masataka; Fukuma, Ryohei; Kishima, Haruhiko; Hirata, Masayuki; Koike, Yasuharu

    2017-01-01

    Studies on brain-machine interface techniques have shown that electrocorticography (ECoG) is an effective modality for predicting limb trajectories and muscle activity in humans. Motor control studies have also identified distributions of “extrinsic-like” and “intrinsic-like” neurons in the premotor (PM) and primary motor (M1) cortices. Here, we investigated whether trajectories and muscle activity predicted from ECoG were obtained based on signals derived from extrinsic-like or intrinsic-like neurons. Three participants carried objects of three different masses along the same counterclockwise path on a table. Trajectories of the object and upper arm muscle activity were predicted using a sparse linear regression. Weight matrices for the predictors were then compared to determine if the ECoG channels contributed more information about trajectory or muscle activity. We found that channels over both PM and M1 contributed highly to trajectory prediction, while a channel over M1 was the highest contributor for muscle activity prediction. PMID:28361947

  1. A conformal field theory of extrinsic geometry of 2-d surfaces

    CERN Document Server

    Viswanathan, K S; Viswanathan, K S; Parthasarathy, R

    1994-01-01

    In the description of the extrinsic geometry of the string world sheet regarded as a conformal immersion of a 2-d surface in R^3, it was previously shown that, restricting to surfaces with h\\surd{g}\\ =\\ 1, where h is the mean scalar curvature and g is the determinant of the induced metric on the surface, leads to Virasaro symmetry. An explicit form of the effective action on such surfaces is constructed in this article which is the extrinsic curvature analog of the WZNW action. This action turns out to be the gauge invariant combination of the actions encountered in 2-d intrinsic gravity theory in light-cone gauge and the geometric action appearing in the quantization of the Virasaro group. This action, besides exhibiting Virasaro symmetry in z-sector, has SL(2,C) conserved currents in the \\bar{z}-sector. This allows us to quantize this theory in the \\bar{z}-sector along the lines of the WZNW model. The quantum theory on h\\surd{g}\\ =\\ 1 surfaces in R^3 is shown to be in the same universality class as the intr...

  2. The determination of the intrinsic and extrinsic parameters of virtual camera based on OpenGL

    Science.gov (United States)

    Li, Suqi; Zhang, Guangjun; Wei, Zhenzhong

    2006-11-01

    OpenGL is the international standard of 3D image. The 3D image generation by OpenGL is similar to the shoot by camera. This paper focuses on the application of OpenGL to computer vision, the OpenGL 3D image is regarded as virtual camera image. Firstly, the imaging mechanism of OpenGL has been analyzed in view of perspective projection transformation of computer vision camera. Then, the relationship between intrinsic and extrinsic parameters of camera and function parameters in OpenGL has been analysed, the transformation formulas have been deduced. Thereout the computer vision simulation has been realized. According to the comparison between the actual CCD camera images and virtual camera images(the parameters of actual camera are the same as virtual camera's) and the experiment results of stereo vision 3D reconstruction simulation, the effectiveness of the method with which the intrinsic and extrinsic parameters of virtual camera based on OpenGL are determined has been verified.

  3. Lineage extrinsic and intrinsic control of immunoregulatory cell numbers by SHIP.

    Science.gov (United States)

    Collazo, Michelle M; Paraiso, Kim H T; Park, Mi-Young; Hazen, Amy L; Kerr, William G

    2012-07-01

    We previously showed that germline or induced SHIP deficiency expands immuno-regulatory cell numbers in T lymphoid and myeloid lineages. We postulated these increases could be interrelated. Here, we show that myeloid-specific ablation of SHIP leads to the expansion of both myeloid-derived suppressor cell (MDSC) and regulatory T (Treg) cell numbers, indicating SHIP-dependent control of Treg-cell numbers by a myeloid cell type. Conversely, T-lineage specific ablation of SHIP leads to expansion of Treg-cell numbers, but not expansion of the MDSC compartment, indicating SHIP also has a lineage intrinsic role in limiting Treg-cell numbers. However, the SHIP-deficient myeloid cell that promotes MDSC and Treg-cell expansion is not an MDSC as they lack SHIP protein expression. Thus, regulation of MDSC numbers in vivo must be controlled in a cell-extrinsic fashion by another myeloid cell type. We had previously shown that G-CSF levels are profoundly increased in SHIP(-/-) mice, suggesting this myelopoietic growth factor could promote MDSC expansion in a cell-extrinsic fashion. Consistent with this hypothesis, we find that G-CSF is required for expansion of the MDSC splenic compartment in mice rendered SHIP-deficient as adults. Thus, SHIP controls MDSC numbers, in part, by limiting production of the myelopoietic growth factor G-CSF.

  4. Extrinsic feedback and management of low back pain: A critical review of the literature.

    Science.gov (United States)

    Ribeiro, Daniel Cury; Sole, Gisela; Abbott, J Haxby; Milosavljevic, Stephan

    2011-06-01

    Effective intervention for low back pain (LBP) can include feedback in one form or other. Although extrinsic feedback (EF) can be provided in a number of ways, most research has not considered how different EF characteristics (e.g. timing and content) influence treatment outcomes. A systematic search related to feedback and LBP was performed on relevant electronic databases. This narrative review aims to describe the forms of feedback provision in the literature regarding management of LBP, and to discuss these in light of previously recommended principles for the use of extrinsic feedback. The present review found support for the provision of EF that focuses on content characteristics including program feedback, summary results feedback, and external focus of attention. Temporal characteristics should enhance the use of intermittent or self-selected feedback. The literature does not support the provision of concurrent or constant EF. As much of the literature related to EF in the management of LBP has not considered content and timing characteristics we have identified future research directions that will clarify the use of content and timing characteristics of EF relative to the management of LBP.

  5. Characterizing Facial Skin Ageing in Humans: Disentangling Extrinsic from Intrinsic Biological Phenomena

    Directory of Open Access Journals (Sweden)

    Carina Trojahn

    2015-01-01

    Full Text Available Facial skin ageing is caused by intrinsic and extrinsic mechanisms. Intrinsic ageing is highly related to chronological age. Age related skin changes can be measured using clinical and biophysical methods. The aim of this study was to evaluate whether and how clinical characteristics and biophysical parameters are associated with each other with and without adjustment for chronological age. Twenty-four female subjects of three age groups were enrolled. Clinical assessments (global facial skin ageing, wrinkling, and sagging, and biophysical measurements (roughness, colour, skin elasticity, and barrier function were conducted at both upper cheeks. Pearson’s correlations and linear regression models adjusted for age were calculated. Most of the measured parameters were correlated with chronological age (e.g., association with wrinkle score, r=0.901 and with each other (e.g., residual skin deformation and wrinkle score, r=0.606. After statistical adjustment for age, only few associations remained (e.g., mean roughness (Rz and luminance (L*,  β=-0.507, R2=0.377. Chronological age as surrogate marker for intrinsic ageing has the most important influence on most facial skin ageing signs. Changes in skin elasticity, wrinkling, sagging, and yellowness seem to be caused by additional extrinsic ageing.

  6. Intrinsic and extrinsic pathway signaling during neuronal apoptosis: lessons from the analysis of mutant mice.

    Science.gov (United States)

    Putcha, Girish V; Harris, Charles A; Moulder, Krista L; Easton, Rachael M; Thompson, Craig B; Johnson, Eugene M

    2002-04-29

    Trophic factor deprivation (TFD)-induced apoptosis in sympathetic neurons requires macromolecular synthesis-dependent BAX translocation, cytochrome c (cyt c) release, and caspase activation. Here, we report the contributions of other intrinsic and extrinsic pathway signals to these processes. Sympathetic neurons expressed all antiapoptotic BCL-2 proteins examined, yet expressed only certain BH3-only and multidomain proapoptotic BCL-2 family members. All coexpressed proapoptotic proteins did not, however, exhibit functional redundancy or compensatory expression, at least in the Bax-/-, Bak-/-, Bim-/-, Bid-/-, and Bad-/- neurons examined. Although the subcellular distribution or posttranslational modification of certain BCL-2 proteins changed with TFD, neither transcriptional nor posttranslational mechanisms regulated the expression or subcellular localization of BID, BAD, or BAK in this paradigm. Despite modest induction of Fas and FasL expression, Fas-mediated signaling did not contribute to TFD-induced apoptosis in sympathetic neurons. Similar findings were obtained with K+ withdrawal-induced apoptosis in cerebellar granule neurons, a model for activity-dependent neuronal survival in the CNS. Thus, expression alone does not guarantee functional redundancy (or compensation) among BCL-2 family members, and, at least in some cells, extrinsic pathway signaling and certain BH3-only proteins (i.e., BID and BAD) do not contribute to BAX-dependent cyt c release or apoptosis caused by TFD.

  7. Simultaneous Intrinsic and Extrinsic Parameter Identification of a Hand-Mounted Laser-Vision Sensor

    Directory of Open Access Journals (Sweden)

    Taikyeong Jeong

    2011-09-01

    Full Text Available In this paper, we propose a simultaneous intrinsic and extrinsic parameter identification of a hand-mounted laser-vision sensor (HMLVS. A laser-vision sensor (LVS, consisting of a camera and a laser stripe projector, is used as a sensor component of the robotic measurement system, and it measures the range data with respect to the robot base frame using the robot forward kinematics and the optical triangulation principle. For the optimal estimation of the model parameters, we applied two optimization techniques: a nonlinear least square optimizer and a particle swarm optimizer. Best-fit parameters, including both the intrinsic and extrinsic parameters of the HMLVS, are simultaneously obtained based on the least-squares criterion. From the simulation and experimental results, it is shown that the parameter identification problem considered was characterized by a highly multimodal landscape; thus, the global optimization technique such as a particle swarm optimization can be a promising tool to identify the model parameters for a HMLVS, while the nonlinear least square optimizer often failed to find an optimal solution even when the initial candidate solutions were selected close to the true optimum. The proposed optimization method does not require good initial guesses of the system parameters to converge at a very stable solution and it could be applied to a kinematically dissimilar robot system without loss of generality.

  8. Toothpastes containing abrasive and chemical whitening agents: efficacy in reducing extrinsic dental staining.

    Science.gov (United States)

    Soares, Cristina Neves Girao Salgado; Amaral, Flavia Lucisano Botelho do; Mesquita, Marcelo Ferraz; Franca, Fabiana Mantovani Gomes; Basting, Roberta Tarkany; Turssi, Cecilia Pedroso

    2015-01-01

    This in vitro study evaluated the efficacy of toothpastes containing abrasive and chemical whitening agents in reducing the extrinsic discoloration of dental enamel. Sixty slabs of dentin from human teeth were sealed so that only the enamel surface was exposed. The enamel surfaces were photographed for initial color assessment. Staining was performed by immersing the dental slabs in 0.2% chlorhexidine solution for 2 minutes and then in black tea for 60 minutes. This process was repeated 15 times. Photographs were taken at the end of the staining process, and the slabs were divided into 5 groups (n = 12), 3 to be brushed with toothpastes containing chemical whitening agents (2 containing phosphate salts and 1 containing phosphate salts plus hydrogen peroxide) and 2 to represent control groups (ordinary/nonwhitening toothpaste and distilled water). The dental slabs were subjected to mechanical toothbrushing with toothpaste slurry or distilled water, according to each group's specifications. After brushing, more photographs were taken for color analysis. The results showed a significant reduction in luminosity after the staining process in addition to an increase in the colors red and yellow (P toothpastes and the changes found in slabs brushed with ordinary toothpaste. The whitening toothpastes did not outperform an ordinary toothpaste in the removal of extrinsic staining.

  9. Direct coupling between charge current and spin polarization by extrinsic mechanisms in graphene

    Science.gov (United States)

    Huang, Chunli; Chong, Y. D.; Cazalilla, Miguel A.

    2016-08-01

    Spintronics—the all-electrical control of the electron spin for quantum or classical information storage and processing—is one of the most promising applications of the two-dimensional material graphene. Although pristine graphene has negligible spin-orbit coupling (SOC), both theory and experiment suggest that SOC in graphene can be enhanced by extrinsic means, such as functionalization by adatom impurities. We present a theory of transport in graphene that accounts for the spin-coherent dynamics of the carriers, including hitherto-neglected spin precession processes taking place during resonant scattering in the dilute impurity limit. We uncover an "anisotropic spin precession" (ASP) scattering process in graphene, which contributes a large current-induced spin polarization and modifies the standard spin Hall effect. ASP scattering arises from two dimensionality and extrinsic SOC, and apart from graphene, it can be present in other 2D materials or in the surface states of 3D materials with a fluctuating SOC. Our theory also yields a comprehensive description of the spin relaxation mechanisms present in adatom-decorated graphene, including Elliot-Yafet and D'yakonov-Perel relaxation rates, the latter of which can become an amplification process in a certain parameter regime of the SOC disorder potential. Our work provides theoretical foundations for designing future graphene-based integrated spintronic devices.

  10. Impact of extrinsic factors on fine motor performance of children attending day care

    Science.gov (United States)

    Corsi, Carolina; dos Santos, Mariana Martins; de Andrade Perez Marques, Luísa; Rocha, Nelci Adriana Cicuto Ferreira

    2016-01-01

    Abstract Objective: To assess the impact of extrinsic factors on fine motor performance of children aged 2-years old. Methods: 73 children attending public and 21 private day care centers were assessed. Day care environment was evaluated using the Infant/Toddler Environment Rating Scale-Revised Edition (ITERS-R), fine motor performance was assessed through the Bayley Scales of Infant and Toddler Development-III (BSITD-III), socioeconomic data, maternal education and time of start at the day care were collected through interviews. Spearman's correlation coefficient was calculated to assess the association between the studied variables. Results: The time at the day care was positively correlated with the children's performance in some fine motor tasks of the BSITD-III, showing that the activities developed in day care centers were important for the refinement of specific motor skills, while the overall fine motor performance by the scale was associated with maternal education and the ITERS-R scale sub-item “language and understanding”. Conclusions: Extrinsic factors such as higher maternal education and quality of day care centers are associated with fine motor performance in children attending day care. PMID:27094472

  11. Extrinsic 2D chirality: giant circular conversion dichroism from a metal-dielectric-metal square array

    Science.gov (United States)

    Cao, Tun; Wei, Chenwei; Mao, Libang; Li, Yang

    2014-01-01

    Giant chiroptical responses routinely occur in three dimensional chiral metamaterials (MMs), but their resonance elements with complex subwavelength chiral shapes are challenging to fabricate in the optical region. Here, we propose a new paradigm for obtaining strong circular conversion dichroism (CCD) based on extrinsic 2D chirality in multilayer achiral MMs, showing that giant chiroptical response can be alternatively attained without complex structures. Our structure consists of an array of thin Au squares separated from a continuous Au film by a GaAs dielectric layer, where the Au squares occupy the sites of a rectangular lattice. This structure gives rise to a pronounced extrinsically 2D-chiral effect (CCD) in the mid-infrared (M-IR) region under an oblique incidence, where the 2D-chiral effect is due to the mutual orientation of the Au squares array and the incident light propagation direction; the large magnitude of CCD due to the large difference between left-to-left and right-to-right circularly polarized reflectance conversion efficiencies. PMID:25501766

  12. Extrinsic calibration of a non-overlapping camera network based on close-range photogrammetry.

    Science.gov (United States)

    Dong, Shuai; Shao, Xinxing; Kang, Xin; Yang, Fujun; He, Xiaoyuan

    2016-08-10

    In this paper, an extrinsic calibration method for a non-overlapping camera network is presented based on close-range photogrammetry. The method does not require calibration targets or the cameras to be moved. The visual sensors are relatively motionless and do not see the same area at the same time. The proposed method combines the multiple cameras using some arbitrarily distributed encoded targets. The calibration procedure consists of three steps: reconstructing the three-dimensional (3D) coordinates of the encoded targets using a hand-held digital camera, performing the intrinsic calibration of the camera network, and calibrating the extrinsic parameters of each camera with only one image. A series of experiments, including 3D reconstruction, rotation, and translation, are employed to validate the proposed approach. The results show that the relative error for the 3D reconstruction is smaller than 0.003%, the relative errors of both rotation and translation are less than 0.066%, and the re-projection error is only 0.09 pixels.

  13. Intrinsic and Extrinsic Chemical and Isotopic Tracers for Characterization Of Groundwater Systems

    Energy Technology Data Exchange (ETDEWEB)

    Moran, J E; Singleton, M J; Carle, S F; Esser, B K

    2007-09-13

    In many regions, three dimensional characterization of the groundwater regime is limited by coarse well spacing or borehole lithologic logs of low quality. However, regulatory requirements for drinking water or site remediation may require collection of extensive chemical and water quality data from existing wells. Similarly, for wells installed in the distant past, lithologic logs may not be available, but the wells can be sampled for chemical and isotopic constituents. In these situations, a thorough analysis of trends in chemical and isotopic constituents can be a key component in characterizing the regional groundwater system. On a basin or subbasin scale, especially in areas of intensive groundwater management where artificial recharge is important, introduction of an extrinsic tracer can provide a robust picture of groundwater flow. Dissolved gases are particularly good tracers since a large volume of water can be tagged, there are no real or perceived health risks associated with the tracer, and a very large dynamic range allows detection of a small amount of tagged water in well discharge. Recent applications of the application of extrinsic tracers, used in concert with intrinsic chemical and isotopic tracers, demonstrate the power of chemical analyses in interpreting regional subsurface flow regimes.

  14. Increased extrinsic apoptotic pathway activity in patients with hepatocellular carcinoma following transarterial embolization

    Institute of Scientific and Technical Information of China (English)

    Shih-Ho Wang; Li-Mien Chen; Wen-Kai Yang; Jane-Dar Lee

    2011-01-01

    AIM: To determine the apoptosis pathway in residual viable hepatocellular carcinoma (HCC) tissues following transarterial embolization (TAE).METHODS: Ten patients with HCC who received surgical resection after TAE were enrolled in the study group, and 24 patients with HCC who received surgical resection only served as the control group. In the study group, we measured the changes in tumor size and a fetoprotein (AFP) levels after TAE. All tissue samples were taken from the residual tumors. The expression of various apoptotic proteins was evaluated via immunoblotting procedures. The results were analyzed using a Student's t test. RESULTS: Tumor size and the AFP level decreased by 46.2% and 55.3% after TAE, respectively. There was no significant difference detected for the Bcl-2/Bax ratio or the cleaved caspase-9 expression levels in either group. However, extrinsic apoptopic pathway-related expression of Fas and cleaved caspase-8 expression were significantly higher in the study group than in the control group (P < 0.05). In addition, cleaved caspase-3 expression in the study group was higher (1.62-fold) than in control group (P < 0.05). CONCLUSION: TAE is an effective palliative therapy that decreases tumor size and AFP levels via an increase in extrinsic apoptosis pathway in patients with unresectable HCC.

  15. Graphene electrodynamics in the presence of the extrinsic spin Hall effect

    Science.gov (United States)

    Huang, Chunli; Chong, Y. D.; Vignale, Giovanni; Cazalilla, Miguel A.

    2016-04-01

    We extend the electrodynamics of two-dimensional electron gases to account for the extrinsic spin Hall effect (SHE). The theory is applied to doped graphene decorated with a random distribution of absorbates that induce spin-orbit coupling (SOC) by proximity. The formalism extends previous semiclassical treatments of the SHE to the nonlocal dynamical regime. Within a particle-number conserving approximation, we compute the conductivity, dielectric function, and spin Hall angle in the small frequency and wave vector limit. The spin Hall angle is found to decrease with frequency and wave number, but it remains comparable to its zero-frequency value around the frequency corresponding to the Drude peak. The plasmon dispersion and linewidth are also obtained. The extrinsic SHE affects the plasmon dispersion in the long wavelength limit, but not at large values of the wave number. This result suggests an explanation for the rather similar plasmonic response measured in exfoliated graphene, which does not exhibit the SHE, and graphene grown by chemical vapor deposition, for which a large SHE has been recently reported. Our theory also lays the foundation for future experimental searches of SOC effects in the electrodynamic response of two-dimensional electron gases with SOC disorder.

  16. The relationship between core self-evaluations, views of god, and intrinsic/extrinsic religious motivation.

    Science.gov (United States)

    Smither, James W; Walker, Alan G

    2015-04-01

    Core self-evaluations refer to a higher-order construct that subsumes four well-established traits in the personality literature: self-esteem, generalized self-efficacy, (low) neuroticism, and (internal) locus of control. Studies that have examined the relationship between various measures of religiosity and individual components of core self-evaluations show no clear pattern of relationships. The absence of a clear pattern may be due to the failure of most previous studies in this area to use theory to guide research. Therefore, theories related to core self-evaluations, religious motivation, and views of God were used to develop and test four hypotheses. 220 adults completed measures of four religious attitudes (intrinsic religious motivation, extrinsic religious motivation, viewing God as loving, and viewing God as punitive), general religiosity, and core self-evaluations, separated by 6 weeks (with the order of measures counterbalanced). Multivariate multiple regression, controlling for general religiosity, showed that core self-evaluations were positively related to viewing God as loving, negatively related to viewing God as punitive, and negatively related to extrinsic religious motivation. The hypothesis that core self-evaluations would be positively related to intrinsic religious motivation was not supported.

  17. Conserved and muscle-group-specific gene expression patterns shape postnatal development of the novel extraocular muscle phenotype.

    Science.gov (United States)

    Cheng, Georgiana; Merriam, Anita P; Gong, Bendi; Leahy, Patrick; Khanna, Sangeeta; Porter, John D

    2004-07-08

    Current models in skeletal muscle biology do not fully account for the breadth, causes, and consequences of phenotypic variation among skeletal muscle groups. The muscle allotype concept arose to explain frank differences between limb, masticatory, and extraocular (EOM) muscles, but there is little understanding of the developmental regulation of the skeletal muscle phenotypic range. Here, we used morphological and DNA microarray analyses to generate a comprehensive temporal profile for rat EOM development. Based upon coordinate regulation of morphologic/gene expression traits with key events in visual, vestibular, and oculomotor system development, we propose a model that the EOM phenotype is a consequence of extrinsic factors that are unique to its local environment and sensory-motor control system, acting upon a novel myoblast lineage. We identified a broad spectrum of differences between the postnatal transcriptional patterns of EOM and limb muscle allotypes, including numerous transcripts not traditionally associated with muscle fiber/group differences. Several transcription factors were differentially regulated and may be responsible for signaling muscle allotype specificity. Significant differences in cellular energetic mechanisms defined the EOM and limb allotypes. The allotypes were divergent in many other functional transcript classes that remain to be further explored. Taken together, we suggest that the EOM allotype is the consequence of tissue-specific mechanisms that direct expression of a limited number of EOM-specific transcripts and broader, incremental differences in transcripts that are conserved by the two allotypes. This represents an important first step in dissecting allotype-specific regulatory mechanisms that may, in turn, explain differential muscle group sensitivity to a variety of metabolic and neuromuscular diseases.

  18. Eye muscle repair - discharge

    Science.gov (United States)

    ... Lazy eye repair - discharge; Strabismus repair - discharge; Extraocular muscle surgery - discharge ... You or your child had eye muscle repair surgery to correct eye muscle ... term for crossed eyes is strabismus. Children most often ...

  19. Muscle strain treatment

    Science.gov (United States)

    Treatment - muscle strain ... Question: How do you treat a muscle strain ? Answer: Rest the strained muscle and apply ice for the first few days after the injury. Anti-inflammatory medicines or acetaminophen ( ...

  20. Ultrasound evaluation of foot muscles and plantar fascia in pes planus.

    Science.gov (United States)

    Angin, Salih; Crofts, Gillian; Mickle, Karen J; Nester, Christopher J

    2014-01-01

    Multiple intrinsic and extrinsic soft tissue structures that apply forces and support the medial longitudinal arch have been implicated in pes planus. These structures have common functions but their interaction in pes planus is not fully understood. The aim of this study was to compare the cross-sectional area (CSA) and thickness of the intrinsic and extrinsic foot muscles and plantar fascia thickness between normal and pes planus feet. Forty-nine adults with a normal foot posture and 49 individuals with pes planus feet were recruited from a university population. Images of the flexor digitorum longus (FDL), flexor hallucis longus (FHL), peroneus longus and brevis (PER), flexor hallucis brevis (FHB), flexor digitorum brevis (FDB) and abductor hallucis (AbH) muscles and the plantar fascia were obtained using a Venue 40 ultrasound system with a 5-13 MHz transducer. The CSA and thickness of AbH, FHB and PER muscles were significantly smaller (AbH -12.8% and -6.8%, FHB -8.9% and -7.6%, PER -14.7% and -10%), whilst FDL (28.3% and 15.2%) and FHL (24% and 9.8%) were significantly larger in the pes planus group. The middle (-10.6%) and anterior (-21.7%) portions of the plantar fascia were thinner in pes planus group. Greater CSA and thickness of the extrinsic muscles might reflect compensatory activity to support the MLA if the intrinsic foot muscle function has been compromised by altered foot structure. A thinner plantar fascia suggests reduced load bearing, and regional variations in structure and function in feet with pes planus. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Very low surface recombination velocity in n-type c-Si using extrinsic field effect passivation

    Science.gov (United States)

    Bonilla, Ruy S.; Woodcock, Frederick; Wilshaw, Peter R.

    2014-08-01

    In this article, field-effect surface passivation is characterised as either intrinsic or extrinsic, depending on the origin of the charges present in passivation dielectric layers. The surface recombination velocity of float zone, 1 Ω cm, n-type silicon was reduced to 0.15 cm/s, the lowest ever observed for a passivating double layer consisting of thermally grown silicon dioxide and plasma enhanced chemical vapour deposited silicon nitride. This result was obtained by enhancing the intrinsic chemical and field-effect passivation of the dielectric layers with uniform, extrinsic field-effect passivation induced by corona discharge. The position and stability of charges, both intrinsic and extrinsic, were characterised and their passivation effect was seen stable for two months with surface recombination velocity field-effect passivation provided a further decrease by a factor of 3.

  2. Extrinsic tracheal compression caused by scoliosis of the thoracic spine and chest wall degormity: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Baek, Kyong min Sarah; Lee, Bae Young; Kim, Hyeon Sook; Song, Kyung Sup; Kang, Hyeon Hul; Lee, Sang Haak; Moon, Hwa Sik [St. Paul' s Hospital, College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of)

    2014-05-15

    Extrinsic airway compression due to chest wall deformity is not commonly observed. Although this condition can be diagnosed more easily with the help of multidetector CT, the standard treatment method has not yet been definitely established. We report a case of an eighteen-year-old male who suffered from severe extrinsic tracheal compression due to scoliosis and straightening of the thoracic spine, confirmed on CT and bronchoscopy. The patient underwent successful placement of tracheal stent but later died of bleeding from the tracheostomy site probably due to tracheo-brachiocephalic artery fistula. We describe the CT and bronchoscopic findings of extrinsic airway compression due to chest wall deformity as well as the optimal treatment method, and discuss the possible explanation for bleeding in the patient along with review of the literature.

  3. Decoupling free-carriers contributions from oxygen-vacancy and cation-substitution in extrinsic conducting oxides.

    Science.gov (United States)

    Lin, Y H; Liu, Y S; Lin, Y C; Wei, Y S; Liao, K S; Lee, K R; Lai, J Y; Chen, H M; Jean, Y C; Liu, C Y

    2013-01-21

    The intrinsic oxygen-vacancies and the extrinsic dopants are two major fundamental free-carrier sources for the extrinsic conducting oxides, such as Sn-doped In(2)O(3). Yet, the individual contributions of the above two free-carrier sources to the total carrier concentrations have never been unraveled. A carrier-concentration separation model is derived in this work, which can define the individual contributions to the total carrier concentration from the intrinsic oxygen-vacancies and the extrinsic dopants, separately. The individual contributions obtained from the present carrier-concentration separation model are verified by the two-state trapping model, photoluminescence, and positron annihilation lifetime (PAL) spectroscopy. In addition, the oxygen-vacancy formation energy of the Sn:In(2)O(3) thin film is determined to be 0.25 eV by PAL spectroscopy.

  4. Neural differences between intrinsic reasons for doing versus extrinsic reasons for doing: an fMRI study.

    Science.gov (United States)

    Lee, Woogul; Reeve, Johnmarshall; Xue, Yiqun; Xiong, Jinhu

    2012-05-01

    The contemporary neural understanding of motivation is based almost exclusively on the neural mechanisms of incentive motivation. Recognizing this as a limitation, we used event-related functional magnetic resonance imaging (fMRI) to pursue the viability of expanding the neural understanding of motivation by initiating a pioneering study of intrinsic motivation by scanning participants' neural activity when they decided to act for intrinsic reasons versus when they decided to act for extrinsic reasons. As expected, intrinsic reasons for acting more recruited insular cortex activity while extrinsic reasons for acting more recruited posterior cingulate cortex (PCC) activity. The results demonstrate that engagement decisions based on intrinsic motivation are more determined by weighing the presence of spontaneous self-satisfactions such as interest and enjoyment while engagement decisions based on extrinsic motivation are more determined by weighing socially-acquired stored values as to whether the environmental incentive is attractive enough to warrant action.

  5. Exploring Intrinsic and Extrinsic Motivations to Participate in a Crowdsourcing Project to Support Blind and Partially Sighted Students.

    Science.gov (United States)

    Layas, Fatma; Petrie, Helen

    2016-01-01

    There have been a number of crowdsourcing projects to support people with disabilities. However, there is little exploration of what motivates people to participate in such crowdsourcing projects. In this study we investigated how different motivational factors can affect the participation of people in a crowdsourcing project to support visually disabled students. We are developing "DescribeIT", a crowdsourcing project to support blind and partially students by having sighted people describe images in digital learning resources. We investigated participants' behavior of the DescribeIT project using three conditions: one intrinsic motivation condition and two extrinsic motivation conditions. The results showed that participants were significantly intrinsically motivated to participate in the DescribeIT project. In addition, participants' intrinsic motivation dominated the effect of the two extrinsic motivational factors in the extrinsic conditions.

  6. Intrinsic and extrinsic drivers of succession: Effects of habitat age and season on an aquatic insect community

    Science.gov (United States)

    Murrell, Ebony G.; Ives, Anthony R.; Juliano, Steven A.

    2014-01-01

    1. Classical studies of succession, largely dominated by plant community studies, focus on intrinsic drivers of change in community composition, such as interspecific competition and changes to the abiotic environment. They often do not consider extrinsic drivers of colonization, such as seasonal phenology, that can affect community change. 2. We investigated both intrinsic and extrinsic drivers of succession for dipteran communities that occupy ephemeral pools, such as those in artificial containers. By initiating communities at different times in the season and following them over time, we compared the relative importance of intrinsic (i.e., habitat age) vs. extrinsic (i.e., seasonal phenology) drivers of succession. 3. We placed water-filled artificial containers in a deciduous forest with 20 containers initiated in each of three months. Containers were sampled weekly to assess community composition. Repeated-measures mixed-effects analysis of community correspondence analysis (CA) scores enabled us to partition intrinsic and extrinsic effects on succession. Covariates of temperature and precipitation were also tested. 4. Community trajectories (as defined by CA) differed significantly with habitat age and season, indicating that both intrinsic and extrinsic effects influence succession patterns. Comparisons of AICcs showed that habitat age was more important than season for species composition. Temperature and precipitation did not explain composition changes beyond those explained by habitat age and season. 5. Quantification of relative strengths of intrinsic and extrinsic effects on succession in dipteran and other ephemeral communities enables us to disentangle processes that must be understood for predicting changes in community composition. PMID:24910493

  7. The role of extrinsic ligaments in maintaining carpal stability - A prospective statistical analysis of 85 arthroscopic cases.

    Science.gov (United States)

    Van Overstraeten, Luc; Camus, Emmanuel J

    2016-02-01

    Several biomechanical studies have shown that the scapholunate (SL) and lunotriquetral (LT) ligaments are not the only stabilizers of the proximal carpal row. However, no study has yet analyzed the range of ligament lesions leading to instability in vivo. Arthroscopy has been used to assess the condition of the wrist's extrinsic ligaments by palpating and tensioning the various ligament and capsule structures. In this prospective study, this arthroscopic method was used in 85 cases of wrist sprain without static instability to evaluate the correlation between lesions of the intrinsic and extrinsic carpal ligaments and carpal instability. In SL instability, a scapholunate interosseous ligament (SLIL) lesion was statistically correlated with lesions of the long radiolunate ligament (P<0.05). There also was a statistically significant correlation between lesions of the SLIL and the radioscaphocapitate, scaphotrapezial and dorsal intercarpal ligaments. There was a correlation between the stage of SL instability and the number of lax extrinsic ligaments (P<0.05) but not with the severity of the extrinsic ligament lesions. In LT instability, a LT interosseous ligament lesion was statistically correlated with lesions of the dorsal intercarpal ligament (P<0.05). There also was a correlation between the stage of LT instability and the number (P<0.005) and severity (P<0.001) of the extrinsic ligament lesions. Arthroscopy can reveal hidden radiographic instability and can also be used to define the number and severity of injured ligaments. In carpal instability, a lesion of one intrinsic carpal ligament was associated with a lesion of one or more extrinsic ligaments.

  8. Newt orthologue of Growth arrest-specific 6 (NvGas6) is implicated in stress response during newt forelimb regeneration.

    Science.gov (United States)

    Beug, Shawn; Vascotto, Sandy G; Tsilfidis, Catherine

    2006-03-01

    Red-spotted newts are capable of regenerating various structures and organs through the process of epimorphic regeneration. Receptor tyrosine kinases (RTKs) and their ligands are important for normal cellular development and physiology but most have not yet been characterised during regeneration. We have isolated a newt orthologue of Growth arrest-specific 6 (NvGas6), and examined its expression during forelimb regeneration and within a blastema cell line (B1H1). During limb regeneration, NvGas6 expression increases upon amputation, peaks during maximal blastema cell proliferation, and is subsequently downregulated during redifferentiation. Transcripts are localised to the wound epithelium and distal mesenchymal cells during dedifferentiation and proliferative phases, and scattered within redifferentiating tissues during later stages. In B1H1 cultures, NvGas6 is upregulated under reduced serum conditions and myogenesis. Treatment with mimosine and colchicine or exposure to heat shock or anoxia results in upregulation of NvGas6 expression. Taken together, our findings suggest that during regeneration, NvGas6 expression may be upregulated in response to cellular stress.

  9. Effects of unilateral and bilateral training in a reaching task on dendritic branching of neurons in the rat motor-sensory forelimb cortex.

    Science.gov (United States)

    Greenough, W T; Larson, J R; Withers, G S

    1985-09-01

    Effects of motor training on a neocortical nerve cell population involved in performance of the motor task were assessed by measuring Layer V pyramidal neuron apical dendritic branching in motor-sensory forelimb cortex of rats trained to reach into a tube for food. Rats were trained to reach with the forepaw they preferred to use (group PRAC), the nonpreferred forepaw (REV), both forepaws (ALT), or neither forepaw (CONT). Across groups, hemispheres opposite trained forepaws had larger apical dendritic fields, in terms of total dendritic length, number of oblique branches from the apical shaft, and length of terminal branches. Similar, although somewhat less consistent, effects were seen when results were analyzed for between- (CONT vs ALT) and within-subject comparisons (trained vs nontrained hemispheres of REV and PRAC). This finding is compatible with the hypothesis that altered dendritic patterns, with associated synapses, are involved in storage of information from the training experience. The within-subject effects mitigate suggestions that these differences arise from generally acting hormonal or metabolic consequences of the training experience, although the possibility that these effects result from neural activity per se and are unrelated to information storage cannot be excluded.

  10. Distribution patterns and predilection muscles of Trichinella zimbabwensis larvae in experimentally infected Nile crocodiles (Crocodylus niloticus Laurenti

    Directory of Open Access Journals (Sweden)

    Louis J. La Grange

    2014-02-01

    Full Text Available No controlled studies have been conducted to determine the predilection muscles of Trichinella zimbabwensis larvae in Nile crocodiles (Crocodylus niloticus or the influence of infection intensity on the distribution of the larvae in crocodiles. The distribution of larvae in muscles of naturally infected Nile crocodiles and experimentally infected caimans (Caiman crocodilus and varans (Varanus exanthematicus have been reported in literature. To determine the distribution patterns of T. zimbabwensis larvae and predilection muscles, 15 crocodiles were randomly divided into three cohorts of five animals each, representing high infection (642 larvae/kg of bodyweight average, medium infection (414 larvae/kg of bodyweight average and low infection (134 larvae/kg of bodyweight average cohorts. In the high infection cohort, high percentages of larvae were observed in the triceps muscles (26% and hind limb muscles (13%. In the medium infection cohort, high percentages of larvae were found in the triceps muscles (50%, sternomastoid (18% and hind limb muscles (13%. In the low infection cohort, larvae were mainly found in the intercostal muscles (36%, longissimus complex (27%, forelimb muscles (20% and hind limb muscles (10%. Predilection muscles in the high and medium infection cohorts were similar to those reported in naturally infected crocodiles despite changes in infection intensity. The high infection cohort had significantly higher numbers of larvae in the sternomastoid, triceps, intercostal, longissimus complex, external tibial flexor, longissimus caudalis and caudal femoral muscles (p < 0.05 compared with the medium infection cohort. In comparison with the low infection cohort, the high infection cohort harboured significantly higher numbers of larvae in all muscles (p < 0.05 except for the tongue. The high infection cohort harboured significantly higher numbers of larvae (p < 0.05 in the sternomastoid, triceps, intercostal, longissimus complex

  11. Predicting the activation states of the muscles governing upper esophageal sphincter relaxation and opening.

    Science.gov (United States)

    Omari, Taher I; Jones, Corinne A; Hammer, Michael J; Cock, Charles; Dinning, Philip; Wiklendt, Lukasz; Costa, Marcello; McCulloch, Timothy M

    2016-03-15

    The swallowing muscles that influence upper esophageal sphincter (UES) opening are centrally controlled and modulated by sensory information. Activation and deactivation of neural inputs to these muscles, including the intrinsic cricopharyngeus (CP) and extrinsic submental (SM) muscles, results in their mechanical activation or deactivation, which changes the diameter of the lumen, alters the intraluminal pressure, and ultimately reduces or promotes flow of content. By measuring the changes in diameter, using intraluminal impedance, and the concurrent changes in intraluminal pressure, it is possible to determine when the muscles are passively or actively relaxing or contracting. From these "mechanical states" of the muscle, the neural inputs driving the specific motor behaviors of the UES can be inferred. In this study we compared predictions of UES mechanical states directly with the activity measured by electromyography (EMG). In eight subjects, pharyngeal pressure and impedance were recorded in parallel with CP- and SM-EMG activity. UES pressure and impedance swallow profiles correlated with the CP-EMG and SM-EMG recordings, respectively. Eight UES muscle states were determined by using the gradient of pressure and impedance with respect to time. Guided by the level and gradient change of EMG activity, mechanical states successfully predicted the activity of the CP muscle and SM muscle independently. Mechanical state predictions revealed patterns consistent with the known neural inputs activating the different muscles during swallowing. Derivation of "activation state" maps may allow better physiological and pathophysiological interpretations of UES function.

  12. Changes in muscle recruitment patterns during skill acquisition.

    Science.gov (United States)

    Carson, R G; Riek, S

    2001-05-01

    The control of movement is predicated upon a system of constraints of musculoskeletal and neural origin. The focus of the present study was upon the manner in which such constraints are adapted or superseded during the acquisition of motor skill. Individuals participated in five experimental sessions, in which they attempted to produce abduction-adduction movements of the index finger in time with an auditory metronome. During each trial, the metronome frequency was increased in eight steps from an individually determined base frequency. Electromyographic (EMG) activity was recorded from first dorsal interosseous (FDI), first volar interosseous (FVI), flexor digitorum superficialis (FDS), and extensor digitorum communis (EDC) muscles. The movements produced on the final day of acquisition more accurately matched the required profile, and exhibited greater spatial and temporal stability, than those generated during initial performance. In the early stages of skill acquisition, an alternating pattern of activation in FDI and FVI was maintained, even at the highest frequencies. In contrast, as the frequency of movement was increased, activity in FDS and EDC was either tonic or intermittent. As learning proceeded, alterations in recruitment patterns were expressed primarily in the extrinsic muscles (EDC and FDS). These changes took the form of increases in the postural role of these muscles, shifts to phasic patterns of activation, or selective disengagement of these muscles. These findings suggest that there is considerable flexibility in the composition of muscle synergies, which is exploited by individuals during the acquisition of coordination.

  13. The foot core system: a new paradigm for understanding intrinsic foot muscle function.

    Science.gov (United States)

    McKeon, Patrick O; Hertel, Jay; Bramble, Dennis; Davis, Irene

    2015-03-01

    The foot is a complex structure with many articulations and multiple degrees of freedom that play an important role in static posture and dynamic activities. The evolutionary development of the arch of the foot was coincident with the greater demands placed on the foot as humans began to run. The movement and stability of the arch is controlled by intrinsic and extrinsic muscles. However, the intrinsic muscles are largely ignored by clinicians and researchers. As such, these muscles are seldom addressed in rehabilitation programmes. Interventions for foot-related problems are more often directed at externally supporting the foot rather than training these muscles to function as they are designed. In this paper, we propose a novel paradigm for understanding the function of the foot. We begin with an overview of the evolution of the human foot with a focus on the development of the arch. This is followed by a description of the foot intrinsic muscles and their relationship to the extrinsic muscles. We draw the parallels between the small muscles of the trunk region that make up the lumbopelvic core and the intrinsic foot muscles, introducing the concept of the foot core. We then integrate the concept of the foot core into the assessment and treatment of the foot. Finally, we call for an increased awareness of the importance of the foot core stability to normal foot and lower extremity function. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  14. ANATOMY OF BONE AND MUSCLE OF SCAPULA AND ARM OF Chrysocyon Brachyurus (CARNIVORA, CANIDAE

    Directory of Open Access Journals (Sweden)

    Saulo Gonçalves Pereira

    2016-10-01

    Full Text Available The maned wolf, Chrysocyon brachyurus - Illiger, 1815, is the largest canid of South America     and its found in the central region of the continent, preferably in open field biomes. It may reach between 20 and 33 kg and up to 125 cm. It is under threat of extinction. Anatomical knowledge is  of great importance to the completion of information about wild species and clinical, surgical, and conservationist implications. This study aimed to describe the bones and the bone accidents of the cingulate forelimb of brachial region and their respective muscles in maned wolf, through dissection procedures of animals preserved in 10% formalin solution. The animals belong to the didactic collection of the Laboratory of Education and Research on Wild Animals of UFU, and are the result of roadkill. The bones are scapula and humerus. There was no clavicula. The muscles are: M. deltoideus; M. supraspinatus; M. infraspinatus; M. teres major; M. teres minor; M. triceps brachii caput: laterale, accessorium, longum and mediale; M. anconeus; M. biceps; M. subscapularis; M.  coracobrachialis; M. tensor fasciae antebrachii; M. brachial. The scapula and arm have specific accidents; however, they are similar to domestic dogs. The humerus is straight. The muscles have some peculiarities. Keywords: anatomy; canids; maned wolf; muscles; osteology.

  15. Using temporal correlations and full distributions to separate intrinsic and extrinsic fluctuations in biological systems

    Science.gov (United States)

    Hilfinger, Andreas; Chen, Mark; Paulsson, Johan

    2013-01-01

    Studies of stochastic biological dynamics typically compare observed fluctuations to theoretically predicted variances, sometimes after separating the intrinsic randomness of the system from the enslaving influence of changing environments. But variances have been shown to discriminate surprisingly poorly between alternative mechanisms, while for other system properties no approaches exist that rigorously disentangle environmental influences from intrinsic effects. Here we apply the theory of generalized random walks in random environments to derive exact rules for decomposing time series and higher statistics rather than just variances. We show for which properties and for which classes of systems intrinsic fluctuations can be analyzed without accounting for extrinsic stochasticity and vice versa. We derive two independent experimental methods to measure the separate noise contributions, and show how to use the additional information in temporal correlations to detect multiplicative effects in dynamical systems. PMID:23368387

  16. Keyword extraction by entropy difference between the intrinsic and extrinsic mode

    Science.gov (United States)

    Yang, Zhen; Lei, Jianjun; Fan, Kefeng; Lai, Yingxu

    2013-10-01

    This paper proposes a new metric to evaluate and rank the relevance of words in a text. The method uses the Shannon’s entropy difference between the intrinsic and extrinsic mode, which refers to the fact that relevant words significantly reflect the author’s writing intention, i.e., their occurrences are modulated by the author’s purpose, while the irrelevant words are distributed randomly in the text. By using The Origin of Species by Charles Darwin as a representative text sample, the performance of our detector is demonstrated and compared to previous proposals. Since a reference text “corpus” is all of an author’s writings, books, papers, etc. his collected works is not needed. Our approach is especially suitable for single documents of which there is no a priori information available.

  17. Delay discounting as a function of intrinsic/extrinsic religiousness, religious fundamentalism, and regular church attendance.

    Science.gov (United States)

    Weatherly, Jeffrey N; Plumm, Karyn M

    2012-01-01

    Delay discounting occurs when the subjective value of an outcome decreases because its delivery is delayed. Previous research has suggested that the rate at which some, but not all, outcomes are discounted varies as a function of regular church attendance. In the present study, 509 participants completed measures of intrinsic religiousness, extrinsic religiousness, religious fundamentalism, and whether they regularly attended church services. They then completed a delay-discounting task involving five outcomes. Although religiousness was not a significant predictor of discounting for all outcomes, participants scoring high in intrinsic religiousness tended to display less delay discounting than participants scoring low. Likewise, participants scoring high in religious fundamentalism tended to display more delay discounting than participants scoring low. These results partially replicate previous ones in showing that the process of discounting may vary as a function of religiousness. The results also provide some direction for those interested in altering how individuals discount.

  18. MODELLING OF EXTRINSIC FIBER OPTIC SAGNAC ULTRASOUND INTERFEROMETER USED FOR DISPLACEMENT MEASUREMENTS

    Directory of Open Access Journals (Sweden)

    S. BENHAMIDA

    2012-06-01

    Full Text Available Ultrasonic waves are used extensively in nondestructive testing both for characterization of material properties, in this paper, we describe a fiber optic sensor suitable for detection of ultrasonic waves. This sensor is based on an extrinsic fiber optic sagnac interferometer. The proposed sensor model can act as a conventional in-phase detector or as a narrowband detector. In this study we use methods interference of ultrasonic waves between the source of ultrasonic waves and the object under investigation is exploited. The main advantages of the proposed sensor are the ability to detect ultrasonic waves on the surface; this sensor possesses higher sensitivity and accuracy than the pulse method. The cavity resonator was very successfully used for measurement of small ultrasound velocity changes. The ultrasonic interferometric technique based on phase-locked loop is the most suitable for measurements of small displacements. This method ensures the highest sensitivity and accuracy.

  19. [Extrinsic allergic alveolitis. Clinical experience at the Instituto National de Enfermedades Respiratorias (INER)].

    Science.gov (United States)

    Chapela-Mendoza, R; Selman-Lama, M

    1999-01-01

    Extrinsic allergic alveolitis is an interstitial lung disease caused by exposure to a variety of inhaled antigens. In Mexico, the most frequent form is due to the inhalation of avian antigens, markedly pigeon proteins. Depending on type and time exposure, the disease presents different clinical forms usually characterized by progressive dyspnea, ground glass or reticulonodular images on chest x rays, a restrictive functional pattern, rest hypoxemia worsening with exercise, and increase of T lymphocytes in bronchoalveolar lavage with an inversion in the helper/suppressor ratio. In this paper, we discuss a 15-year experience with this pathological problem in Mexico, emphasizing the differences with this disorder in Caucasian populations. Generally, our patients display a chronic form of the disease, which evolves to fibrosis in about one-half of the patients. In this sense, the diagnostic, prognostic, and therapeutic focusing exhibit different elements, and thus the development of clinical and basic research is strongly required.

  20. Factors influencing diversification in angiosperms: at the crossroads of intrinsic and extrinsic traits.

    Science.gov (United States)

    Vamosi, Jana C; Vamosi, Steven M

    2011-03-01

    Recent studies indicate that both key innovations and available area influence species richness in angiosperms. Available area has been observed to have the greatest effect, however, and appears to alter the "carrying capacity" of a lineage rather than alter diversification rates. Here, we review and weigh the evidence of predictors of angiosperm diversification and further dissect how area can place ecological limits on diversification of angiosperms, specifically addressing the following: (1) theoretical mechanisms by which particular intrinsic and extrinsic traits may affect diversification in angiosperm families; (2) evidence that the amount of available area determines the ecological limits on lineages; and (3) geographical distribution of diversification hotspots in angiosperms, concentrating on the effects of zygomorphy, noncontiguous area, and latitude. While we found that dispersal to numerous noncontiguous areas is most important in spurring diversification, diversification of tropical and zygomorphic families appears to be elevated by the generation of more species per given area.